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Papers by Anchalee Jintapattanakit

Research paper thumbnail of Physicochemical properties and biocompatibility of N-trimethyl chitosan: Effect of quaternization and dimethylation

European Journal of Pharmaceutics and Biopharmaceutics, Oct 1, 2008

The aim of this research was to investigate the effect of degrees of quaternization (DQ) and dime... more The aim of this research was to investigate the effect of degrees of quaternization (DQ) and dimethylation (DD) on physicochemical properties and cytotoxicity of N-trimethyl chitosan (TMC). TMC was synthesized by reductive methylation of chitosan in the presence of a strong base at elevated temperature and polymer characteristics were investigated. The number of methylation process and duration of reaction were demonstrated to affect the DQ and DD. An increased number of reaction steps increased DQ and decreased DD, while an extended duration of reaction increased both DQ and DD. The molecular weight of TMC was in the range of 60-550kDa. From the Mark-Houwink equation, it was found that TMC in 2% acetic acid/0.2M sodium acetate behaved as a spherical structure, approximating a random coil. The highest solubility was found with TMC of an intermediate DQ (40%) regardless of DD and molecular weight. The effect of DD on the physicochemical properties and cytotoxicity was obviously observed when proportion of DD to DQ was higher than 1. TMC with relatively high DD showed reduction in both solubility and mucoadhesion and hence decreased cytotoxicity. However, the influence of DD was insignificant when DQ of TMC was higher than 40% at which physicochemical properties and cytotoxicity were mainly dependent upon DQ.

Research paper thumbnail of Formulation and Pharmaceutical Evaluation of Extemporaneous α-arbutin Creams for the Treatment of Melasma

International journal of pharmaceutical compounding, 2021

Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases... more Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases as an extemporaneous preparation for melasma treatment. Cream bases were formulated with two pH values, 4.0 and 5.5, using a hot process. The stability of the creams was studied for 60 days under three storage conditions (i.e., 2°C to 8°C, 30°C, 40°C). Cream characteristics and all aspects of product stability including physical, chemical, and microbial were investigated. Stability was defined as no dramatic change in color, viscosity, pH, and no visible microbial growth. For stability, at least 90% of the initial a-arbutin concentration quantified by stability-indicating high-performance liquid chromatography must be obtained. It was found that pH had no influence on the a-arbutin or formulations' stability. All formulations had a-arbutin remaining higher than 90% (approximately 92%) after being stored for 60 days in all storage conditions with no significant changes in pH or visco...

Research paper thumbnail of Enhanced stability and skin permeation of ibuprofen-loaded solid lipid nanoparticles based binary solid lipid matrix: Effect of surfactant and lipid compositions

International Journal of Pharmaceutics: X

Research paper thumbnail of Self-Assembled Polyelectrolyte Nanocomplexes between Chitosan Derivatives and Insulin

Journal of Pharmaceutical Sciences, May 1, 2006

Polyelectrolyte complexes (PEC) formed from chitosan derivatives and insulin was prepared and par... more Polyelectrolyte complexes (PEC) formed from chitosan derivatives and insulin was prepared and parameters influencing complex formation were characterized. Turbidimetric titration, in combination with dynamic light scattering (DLS) and laser doppler anemometry (LDA), were used to study the complexation process. The morphology of the PECs was determined using atomic force microscopy (AFM). PEC formation was predominantly pH-dependent. Complexation with insulin occurred only above critical pH value (pHc) of 6.0 for all the chitosan derivatives investigated. Soluble PECs in the size range of 200-500 nm with spherical or subspherical morphology and smooth surface structure were obtained at optimized polymer/insulin charge ratios. Optimal conditions were obtained when the pH of PECs was in the range of 6.5-8.0, depending on polymer structure. The stability of PECs was influenced by polymer chain length. Only when the MW of the polymers was !25-kDa PEC precipitation could be avoided. An increase in the ionic strength of the medium accelerated complex dissociation. Chitosan methylation and PEGylation significantly improved the stability of insulin in the PECs. Moreover, the PEC could protect insulin from degradation even at 508C for at least 6 h. All complexes could be lyophilized without influencing the particle size, complex concentration, and stability of insulin. On the basis of our results, we suggest that interactions involved in PEC formation were predominantly electrostatic in nature, involving the positively charged amino groups of chitosan and the negatively charged insulin above its isoelectric point. Intranasal absorption of the polyelectrolyte nanocomplexes will be studied in vivo.

Research paper thumbnail of Stability of Extemporaneously Prepared Amitriptyline Hydrochloride Topical Preparations for the Treatment of Neuropathic Pain

Siriraj Medical Journal

Objective: The aim of this study was to investigate the physicochemical and microbiological stabi... more Objective: The aim of this study was to investigate the physicochemical and microbiological stability of extemporaneous amitriptyline hydrochloride (AMH) topical preparations for the treatment of neuropathic pain. Materials and Methods: AMH tablets were triturated to produce fine powders with a mortar and pestle. These powders were levigated and separately incorporated into four compounding bases: hydrophilic petrolatum USP, anionic cream, cold cream USP, and pluronic lecithin organogel (PLO) having the concentration of 2%w/w AMH. Results: In the in vitro release study, the most significant amount of AMH was released from the PLO, followed by cold cream, anionic cream and hydrophilic petrolatum, respectively; therefore, the compounded AMH in cold cream and AMH in PLO were selected for the evaluation of the in vitro permeation and product stability. The permeation of AMH from PLO across human epidermal membrane was significantly greater than that from the cold cream.Product stability...

Research paper thumbnail of Intranasal delivery of self-assembly insulin nanocomplexes based on surface modified trimethyl chitosan /

Research paper thumbnail of Putative hydrophobins of black poplar mushroom (Agrocybe cylindracea)

Mycology, 2020

ABSTRACT Hydrophobin proteins were extracted from Agrocybe cylindracea mycelia, the culture media... more ABSTRACT Hydrophobin proteins were extracted from Agrocybe cylindracea mycelia, the culture media (potato dextrose broth, PDB), and fruiting bodies. The putative hydrophobins obtained showed approximate sizes ranging from 8.0 to 25.0 kDa, dependent on their source. Multiple hydrophobin protein bands were detected in fruiting bodies. The hydrophobin yielded from aerial mycelia, or fruiting bodies, was approximately 6 mg/g dried weight. The crude extracts were examined for their properties in regards to surface modification, emulsification, and surface activity. Coating of hydrophobic Teflon sheet with crude extract made the surface significantly hydrophilic, whereas exposure of glass surfaces to extracts resulted in enhanced hydrophobicity. Crude extracts from culture media of A. cylindracea displayed emulsifying activity when mixed with hexane and could significantly reduce the surface tension of 60% ethanol and deionised water. The putative hydrophobin protein band from culture media (9.6 kDa), as analysed using LC-MS/MS, contained an amino acid fragment structurally similar to class I hydrophobin proteins from Basidiomycetes.

Research paper thumbnail of Formulation and Pharmaceutical Evaluation of Extemporaneous α-arbutin Creams for the Treatment of Melasma

International journal of pharmaceutical compounding, 2021

Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases... more Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases as an extemporaneous preparation for melasma treatment. Cream bases were formulated with two pH values, 4.0 and 5.5, using a hot process. The stability of the creams was studied for 60 days under three storage conditions (i.e., 2°C to 8°C, 30°C, 40°C). Cream characteristics and all aspects of product stability including physical, chemical, and microbial were investigated. Stability was defined as no dramatic change in color, viscosity, pH, and no visible microbial growth. For stability, at least 90% of the initial a-arbutin concentration quantified by stability-indicating high-performance liquid chromatography must be obtained. It was found that pH had no influence on the a-arbutin or formulations' stability. All formulations had a-arbutin remaining higher than 90% (approximately 92%) after being stored for 60 days in all storage conditions with no significant changes in pH or visco...

Research paper thumbnail of Preparation of nanoemulsions by phase inversion temperature (PIT)

Pharmaceutical Sciences Asia, 2018

Nowadays, there is an increasing interest in the utilization of nanoemulsions in many industries,... more Nowadays, there is an increasing interest in the utilization of nanoemulsions in many industries, such as pharmaceuticals, food and beverage, cosmetics and agrochemicals because of a number of potential advantages over conventional emulsions (i.e., increased bioavailability, enhanced long-term stability and high optical clarity) and microemulsions (i.e., relatively low amount of surfactant used). The productions of nanoemulsions are typically divided into high-energy and low-energy emulsification methods. High-energy methods involve the use of mechanical devices to break up particles into smaller sizes. In contrast, lowenergy methods divert the intrinsic physicochemical properties of surfactants, co-surfactants and excipients in the formulation, leading to the generation of emulsion droplets in the nanometric range. Owing to the advantages of low-energy methods (i.e., low cost and ease of implementation), there is considerable interest in the productions of nanoemulsions using low-energy methods, namely spontaneous emulsification, phase inversion composition, and phase inversion temperature (PIT). Among these, the PIT method is the most widely used in industry and has evidenced the progress in the knowledge of the factors leading to nanoemulsions with minimum size and low polydispersity index. In this review, the principle of the PIT method is presented. The major factors influencing nanoemulsion formation using the PIT method and its applications to other lipid-based nanocarriers are reviewed.

Research paper thumbnail of Vegetable oil-based nanoemulsions containing curcuminoids: Formation optimization by phase inversion temperature method

Journal of Drug Delivery Science and Technology, 2018

Antiretroviral therapy and its major scaling up over the past decade has contributed to improving... more Antiretroviral therapy and its major scaling up over the past decade has contributed to improving the quality of life of people living with HIV, but the mortality associated with this pandemic remains a concern in our environment and opportunistic infections are the major causes of death in most patients. The objective is to determine the causes of patients' deaths living with HIV at the Lubumbashi University Center of Excellence. A documentary review of patients was conducted from May 2011 to December 2015. Death is considered HIV-related if it is the result of an opportunistic infection in any patient with CD4 less than 200/mm 3. 1717 patients were recruited to the center of excellence between May 2011 and December 2015, the mortality rate was 24.1% patient year, 67.95% women and 32.05% male 76.63% of patients had CD 4 less than 200 mm 3. 86% of the causes were directly related to HIV, Cryptococcal neuromeningitis comes first with 16.6%, while tuberculosis follows with 15.3%; 8% of the causes were not directly related to HIV, it is notably hepatopathies with 2.6%.

Research paper thumbnail of Enhanced supersaturation of chlortetracycline hydrochloride by amorphous solid dispersion

Journal of Drug Delivery Science and Technology, 2018

RESUMEN: Los hábitos deformantes orales son una de las principales causas de las maloclusiones, e... more RESUMEN: Los hábitos deformantes orales son una de las principales causas de las maloclusiones, entre los más frecuentes tenemos: la succión digital, el empuje lingual, la onicofagia, la queilofagia, la respiración oral y la masticación de objetos. El objetivo de este estudio fué efectuar una evaluación y análisis de la evidencia científica disponible actualizada en los últimos 7 años sobre los hábitos deformantes orales en preescolares y escolares de 3 a 12 años de edad. Se realizó una revisión sistemática de la literatura en bases de datos referativos como: Scielo, LILACS, GOOGLE ACADÉMICO, en artículos publicados sobre hábitos orales deformantes presentes en niños preescolares y escolares de 3 a 12 años de edad, con fechas de publicación que datan del 2010 al 2017, no hubo restricción en cuanto a sexo o zona geográfica. Se encontró una alta incidencia de hábitos deformantes orales en países de América latina, Centro américa y el Caribe; en países como Cuba la incidencia fue muy alta, el hábito que tuvo mayor prevalencia en la muestra fue la Onicofagia seguido de la disfunción lingual, resultados similares se reflejaron en países como Venezuela, México y Colombia. Los resultados de esta revisión evidencian la importancia del estudio de los hábitos deformantes orales, los cuales constituyen una de las principales causas de las maloclusiones, que a su vez son el tercer problema de salud bucodental. En su gran mayoría, de los artículos tomados como referencia demostraron que no existe una diferencia estadísticamente significativa respecto al sexo y la prevalencia de hábitos parafuncionales. Se destaca la importancia de implementar nuevos proyectos de investigación respecto a los hábitos parafuncionales en la población preescolar y escolar, acompañado de programas educativo en nuestro país Ecuador, ya que en la actualidad fueron pocas las publicaciones que pudimos tomar de referencia. PALABRAS CLAVE: hábitos orales deformantes, hábitos orales, dentición temporaria, dentición mixta, maloclusión.

Research paper thumbnail of Effect of binary solid lipid matrix of wax and triglyceride on lipid crystallinity, drug-lipid interaction and drug release of ibuprofen-loaded solid lipid nanoparticles (SLN) for dermal delivery

Journal of Colloid and Interface Science, 2017

Effect of binary solid lipid matrix of wax and triglyceride on lipid crystallinity, druglipid int... more Effect of binary solid lipid matrix of wax and triglyceride on lipid crystallinity, druglipid interaction and drug release of ibuprofen-loaded solid lipid nanoparticles (SLN) for dermal delivery,

Research paper thumbnail of Effect of Tripolyphosphate on Physical and Enzymatic Stabilities of Insulin Loaded Nanoparticles of N-Trimethyl Chitosan

The aim of the present work was to elucidate the influence of tripolyphosphate (TPP) on the collo... more The aim of the present work was to elucidate the influence of tripolyphosphate (TPP) on the colloidal and insulin stabilities. Using a trimethyl chitosan (TMC) with quaternization degree of 40%, insulin loaded nanoparticles were prepared by ionotropic gelation with TPP crosslinker. The nanoparticles were characterized for size, zeta potential, insulin loading, process yield, colloidal stability and the protection capability of insulin against enzymatic degradation of trypsin. The results showed that insulin nanoparticles were in the range of 200-260 nm with spherical or oval morphology. The highest insulin loading efficiency of nanoparticles with narrow size distribution was achieved when TPP:TMC:insulin mass ratio of 0.4:1:1 was used. The colloidal stability was TPP concentration dependent. The presence of TPP accelerated the degradation of free insulin and insulin loaded nanoparticles which increased with increasing TPP concentration. Therefore, the preparation of nanoparticles by ionotropic gelation with TPP would not be suitable for the development of insulin delivery system. ©All right reserved.

Research paper thumbnail of Nasal absorption and local tissue reaction of insulin nanocomplexes of trimethyl chitosan derivatives in rats

The Journal of pharmacy and pharmacology, 2010

The objective of this work was to explore the potential and safety of trimethyl chitosan (TMC) an... more The objective of this work was to explore the potential and safety of trimethyl chitosan (TMC) and PEGylated TMC for improved absorption of insulin after nasal administration. The nasal absorption of insulin nanocomplexes of TMC or PEGylated TMC was evaluated in anaesthetized rats. Concomitantly, the histopathological effects of these nanocomplexes on rat nasal mucosa were studied using a perfusion fixation technique. All insulin nanocomplexes containing TMC or PEGylated TMC showed a 34-47% reduction in the blood glucose concentration, when the insulin absorption through the rat nasal mucosa was measured indirectly. In addition, the relative pharmacodynamic bioavailability (F(dyn)) of the formulations was found to be dependent upon the charge ratio of insulin and polymer, regardless of polymer structure. The F(dyn) apparently decreased with increasing charge ratio of insulin : polymer. Although acute alterations in nasal morphology by the formulations were affected by the charge rat...

Research paper thumbnail of Influence of chemical penetration enhancers on skin permeability of ellagic acid-loaded niosomes

Asian Journal of Pharmaceutical Sciences, 2013

This study aimed to develop niosomes of ellagic acid (EA), a potent antioxidant phytochemical sub... more This study aimed to develop niosomes of ellagic acid (EA), a potent antioxidant phytochemical substance, for dermal delivery and to investigate the influence of chemical penetration enhancers on the physicochemical properties of EA-loaded niosomes. The EA niosomes were prepared by reverse phase evaporation method using Span 60, Tween 60 and cholesterol as vesicle forming agents and Solulan C24 as a steric stabilizer. Polyethylene glycol 400 (PEG) was used as a solubilizer while dimethylsulfoxide (DMSO) or Nmethyl-2-pyrrolidone (NMP) was used as a skin penetration enhancer. It was found that the mean particle sizes of EA-loaded niosomes were in the range of 312e402 nm with PI values of lower than 0.4. The niosomes were determined to be spherical multilamellar vesicles as observed by transmission electron microscope and optical microscopy. All niosomes were

Research paper thumbnail of Preparation of Virgin Coconut Oil Nanoemulsions by Phase Inversion Temperature Method

Advanced Materials Research, 2014

Presently, the low energy emulsification method; phase inversion temperature (PIT) method offers ... more Presently, the low energy emulsification method; phase inversion temperature (PIT) method offers a convenient mean of nanoemulsion formation for the incorporation of fragile substances. The aim of the current study was to prepare coconut oil nanoemulsions using cremophor RH 40 as nonionic surfactant in the light of PIT method. The suitable composition of coconut oil, cremophor RH40 and water was investigated by construction of ternary phase diagram. The PIT of system can be adjusted to 75 °C by adding NaCl at the concentration of 6%(w/w). Stable translucent nanoemulsions with particle size in range of 20-100 nm and PDI<0.2 can be formed at the constituent proportions of 5%-30%(w/w), coconut oil, 10%-80%(w/w) cremophor RH40 and 5%-85%(w/w) NaCl solution of 6%(w/w). All formulations were stable for up to 2 months when stored at 4, 30 and 40 °C and protected from light.

Research paper thumbnail of The role of mucoadhesion of trimethyl chitosan and PEGylated trimethyl chitosan nanocomplexes in insulin uptake

Journal of Pharmaceutical Sciences, 2009

The aim of this work was to investigate the role of mucoadhesion in the insulin uptake of nanocom... more The aim of this work was to investigate the role of mucoadhesion in the insulin uptake of nanocomplexes (NC) based of trimethyl chitosan (TMC) and poly(ethylene glycol) (PEG)-graft-TMC copolymers. Self-assembled insulin NC were prepared by polyelectrolyte complexation. The effects of PEGylation and positive charge density on mucoadhesion were assessed using a mucin assay and mucus-secreting HT29-MTX-E12 (E12) monolayers. The behaviors of corresponding insulin NC after adhesion to E12 were also established. All PEGylated TMC copolymers showed significantly higher levels of adhesion to mucus than unmodified TMC. The copolymer composed of 298 PEG chains per TMC macromolecules exhibited the highest level of mucoadhesion, being 3.4 times higher than TMC. The higher mucoadhesive properties of PEGylated TMC copolymers resulted from the synergistic effects of interpenetration of PEG chains into the mucus and electrostatic interaction between positive charged TMC and anionic glycoproteins present in the mucus layer. Compared to TMC, insulin NC based on PEGylated TMC copolymers demonstrated no evidence of insulin uptake improvement due to complete release of insulin from NC after adhering to mucus. CLSM revealed the localization of TMC and its corresponding insulin NC at cell surface membranes of E12.

Research paper thumbnail of Physicochemical properties and biocompatibility of N-trimethyl chitosan: Effect of quaternization and dimethylation

European Journal of Pharmaceutics and Biopharmaceutics, 2008

The aim of this research was to investigate the effect of degrees of quaternization (DQ) and dime... more The aim of this research was to investigate the effect of degrees of quaternization (DQ) and dimethylation (DD) on physicochemical properties and cytotoxicity of N-trimethyl chitosan (TMC). TMC was synthesized by reductive methylation of chitosan in the presence of a strong base at elevated temperature and polymer characteristics were investigated. The number of methylation process and duration of reaction were demonstrated to affect the DQ and DD. An increased number of reaction steps increased DQ and decreased DD, while an extended duration of reaction increased both DQ and DD. The molecular weight of TMC was in the range of 60-550 kDa. From the Mark-Houwink equation, it was found that TMC in 2% acetic acid/0.2 M sodium acetate behaved as a spherical structure, approximating a random coil. The highest solubility was found with TMC of an intermediate DQ (40%) regardless of DD and molecular weight. The effect of DD on the physicochemical properties and cytotoxicity was obviously observed when proportion of DD to DQ was higher than 1. TMC with relatively high DD showed reduction in both solubility and mucoadhesion and hence decreased cytotoxicity. However, the influence of DD was insignificant when DQ of TMC was higher than 40% at which physicochemical properties and cytotoxicity were mainly dependent upon DQ.

Research paper thumbnail of Peroral delivery of insulin using chitosan derivatives: a comparative study of polyelectrolyte nanocomplexes and nanoparticles

International journal of pharmaceutics, Jan 5, 2007

Polymeric delivery systems based on nanoparticles (NP) have emerged as a promising approach for p... more Polymeric delivery systems based on nanoparticles (NP) have emerged as a promising approach for peroral insulin delivery. Using a trimethyl chitosan (TMC) and a PEG-graft-TMC copolymer, polyelectrolyte complexes (PEC) and nanoparticles were prepared and their properties were compared. The amount of insulin was quantified by HPLC and the stability of PEC and NP upon exposure to simulated gastrointestinal (GI) fluid was monitored by dynamic laser light scattering. It was shown that polymer/insulin (+/-) charge ratio played an important role in PEC and NP formation. Stable, uniform, and spherical PEC/NP with high insulin association efficiency (AE) were formed at or close to optimized polymer/insulin (+/-) charge ratio, depending on polymer structure. All PEC were more stable in pH 6.8 simulated intestinal fluid (SIF) than NP. The PEC also appeared to play some role in protecting insulin from degradation at higher temperature and with proteolytic enzyme more efficiently than NP. On the...

Research paper thumbnail of Self-assembled polyelectrolyte nanocomplexes between chitosan derivatives and insulin

Journal of Pharmaceutical Sciences, 2006

Polyelectrolyte complexes (PEC) formed from chitosan derivatives and insulin was prepared and par... more Polyelectrolyte complexes (PEC) formed from chitosan derivatives and insulin was prepared and parameters influencing complex formation were characterized. Turbidimetric titration, in combination with dynamic light scattering (DLS) and laser doppler anemometry (LDA), were used to study the complexation process. The morphology of the PECs was determined using atomic force microscopy (AFM). PEC formation was predominantly pH-dependent. Complexation with insulin occurred only above critical pH value (pHc) of 6.0 for all the chitosan derivatives investigated. Soluble PECs in the size range of 200-500 nm with spherical or subspherical morphology and smooth surface structure were obtained at optimized polymer/insulin charge ratios. Optimal conditions were obtained when the pH of PECs was in the range of 6.5-8.0, depending on polymer structure. The stability of PECs was influenced by polymer chain length. Only when the MW of the polymers was !25-kDa PEC precipitation could be avoided. An increase in the ionic strength of the medium accelerated complex dissociation. Chitosan methylation and PEGylation significantly improved the stability of insulin in the PECs. Moreover, the PEC could protect insulin from degradation even at 508C for at least 6 h. All complexes could be lyophilized without influencing the particle size, complex concentration, and stability of insulin. On the basis of our results, we suggest that interactions involved in PEC formation were predominantly electrostatic in nature, involving the positively charged amino groups of chitosan and the negatively charged insulin above its isoelectric point. Intranasal absorption of the polyelectrolyte nanocomplexes will be studied in vivo.

Research paper thumbnail of Physicochemical properties and biocompatibility of N-trimethyl chitosan: Effect of quaternization and dimethylation

European Journal of Pharmaceutics and Biopharmaceutics, Oct 1, 2008

The aim of this research was to investigate the effect of degrees of quaternization (DQ) and dime... more The aim of this research was to investigate the effect of degrees of quaternization (DQ) and dimethylation (DD) on physicochemical properties and cytotoxicity of N-trimethyl chitosan (TMC). TMC was synthesized by reductive methylation of chitosan in the presence of a strong base at elevated temperature and polymer characteristics were investigated. The number of methylation process and duration of reaction were demonstrated to affect the DQ and DD. An increased number of reaction steps increased DQ and decreased DD, while an extended duration of reaction increased both DQ and DD. The molecular weight of TMC was in the range of 60-550kDa. From the Mark-Houwink equation, it was found that TMC in 2% acetic acid/0.2M sodium acetate behaved as a spherical structure, approximating a random coil. The highest solubility was found with TMC of an intermediate DQ (40%) regardless of DD and molecular weight. The effect of DD on the physicochemical properties and cytotoxicity was obviously observed when proportion of DD to DQ was higher than 1. TMC with relatively high DD showed reduction in both solubility and mucoadhesion and hence decreased cytotoxicity. However, the influence of DD was insignificant when DQ of TMC was higher than 40% at which physicochemical properties and cytotoxicity were mainly dependent upon DQ.

Research paper thumbnail of Formulation and Pharmaceutical Evaluation of Extemporaneous α-arbutin Creams for the Treatment of Melasma

International journal of pharmaceutical compounding, 2021

Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases... more Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases as an extemporaneous preparation for melasma treatment. Cream bases were formulated with two pH values, 4.0 and 5.5, using a hot process. The stability of the creams was studied for 60 days under three storage conditions (i.e., 2°C to 8°C, 30°C, 40°C). Cream characteristics and all aspects of product stability including physical, chemical, and microbial were investigated. Stability was defined as no dramatic change in color, viscosity, pH, and no visible microbial growth. For stability, at least 90% of the initial a-arbutin concentration quantified by stability-indicating high-performance liquid chromatography must be obtained. It was found that pH had no influence on the a-arbutin or formulations&amp;#39; stability. All formulations had a-arbutin remaining higher than 90% (approximately 92%) after being stored for 60 days in all storage conditions with no significant changes in pH or visco...

Research paper thumbnail of Enhanced stability and skin permeation of ibuprofen-loaded solid lipid nanoparticles based binary solid lipid matrix: Effect of surfactant and lipid compositions

International Journal of Pharmaceutics: X

Research paper thumbnail of Self-Assembled Polyelectrolyte Nanocomplexes between Chitosan Derivatives and Insulin

Journal of Pharmaceutical Sciences, May 1, 2006

Polyelectrolyte complexes (PEC) formed from chitosan derivatives and insulin was prepared and par... more Polyelectrolyte complexes (PEC) formed from chitosan derivatives and insulin was prepared and parameters influencing complex formation were characterized. Turbidimetric titration, in combination with dynamic light scattering (DLS) and laser doppler anemometry (LDA), were used to study the complexation process. The morphology of the PECs was determined using atomic force microscopy (AFM). PEC formation was predominantly pH-dependent. Complexation with insulin occurred only above critical pH value (pHc) of 6.0 for all the chitosan derivatives investigated. Soluble PECs in the size range of 200-500 nm with spherical or subspherical morphology and smooth surface structure were obtained at optimized polymer/insulin charge ratios. Optimal conditions were obtained when the pH of PECs was in the range of 6.5-8.0, depending on polymer structure. The stability of PECs was influenced by polymer chain length. Only when the MW of the polymers was !25-kDa PEC precipitation could be avoided. An increase in the ionic strength of the medium accelerated complex dissociation. Chitosan methylation and PEGylation significantly improved the stability of insulin in the PECs. Moreover, the PEC could protect insulin from degradation even at 508C for at least 6 h. All complexes could be lyophilized without influencing the particle size, complex concentration, and stability of insulin. On the basis of our results, we suggest that interactions involved in PEC formation were predominantly electrostatic in nature, involving the positively charged amino groups of chitosan and the negatively charged insulin above its isoelectric point. Intranasal absorption of the polyelectrolyte nanocomplexes will be studied in vivo.

Research paper thumbnail of Stability of Extemporaneously Prepared Amitriptyline Hydrochloride Topical Preparations for the Treatment of Neuropathic Pain

Siriraj Medical Journal

Objective: The aim of this study was to investigate the physicochemical and microbiological stabi... more Objective: The aim of this study was to investigate the physicochemical and microbiological stability of extemporaneous amitriptyline hydrochloride (AMH) topical preparations for the treatment of neuropathic pain. Materials and Methods: AMH tablets were triturated to produce fine powders with a mortar and pestle. These powders were levigated and separately incorporated into four compounding bases: hydrophilic petrolatum USP, anionic cream, cold cream USP, and pluronic lecithin organogel (PLO) having the concentration of 2%w/w AMH. Results: In the in vitro release study, the most significant amount of AMH was released from the PLO, followed by cold cream, anionic cream and hydrophilic petrolatum, respectively; therefore, the compounded AMH in cold cream and AMH in PLO were selected for the evaluation of the in vitro permeation and product stability. The permeation of AMH from PLO across human epidermal membrane was significantly greater than that from the cold cream.Product stability...

Research paper thumbnail of Intranasal delivery of self-assembly insulin nanocomplexes based on surface modified trimethyl chitosan /

Research paper thumbnail of Putative hydrophobins of black poplar mushroom (Agrocybe cylindracea)

Mycology, 2020

ABSTRACT Hydrophobin proteins were extracted from Agrocybe cylindracea mycelia, the culture media... more ABSTRACT Hydrophobin proteins were extracted from Agrocybe cylindracea mycelia, the culture media (potato dextrose broth, PDB), and fruiting bodies. The putative hydrophobins obtained showed approximate sizes ranging from 8.0 to 25.0 kDa, dependent on their source. Multiple hydrophobin protein bands were detected in fruiting bodies. The hydrophobin yielded from aerial mycelia, or fruiting bodies, was approximately 6 mg/g dried weight. The crude extracts were examined for their properties in regards to surface modification, emulsification, and surface activity. Coating of hydrophobic Teflon sheet with crude extract made the surface significantly hydrophilic, whereas exposure of glass surfaces to extracts resulted in enhanced hydrophobicity. Crude extracts from culture media of A. cylindracea displayed emulsifying activity when mixed with hexane and could significantly reduce the surface tension of 60% ethanol and deionised water. The putative hydrophobin protein band from culture media (9.6 kDa), as analysed using LC-MS/MS, contained an amino acid fragment structurally similar to class I hydrophobin proteins from Basidiomycetes.

Research paper thumbnail of Formulation and Pharmaceutical Evaluation of Extemporaneous α-arbutin Creams for the Treatment of Melasma

International journal of pharmaceutical compounding, 2021

Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases... more Concentrated 7% w/w a-arbutin cream was formulated and evaluated using O/W and W/O emulsion bases as an extemporaneous preparation for melasma treatment. Cream bases were formulated with two pH values, 4.0 and 5.5, using a hot process. The stability of the creams was studied for 60 days under three storage conditions (i.e., 2°C to 8°C, 30°C, 40°C). Cream characteristics and all aspects of product stability including physical, chemical, and microbial were investigated. Stability was defined as no dramatic change in color, viscosity, pH, and no visible microbial growth. For stability, at least 90% of the initial a-arbutin concentration quantified by stability-indicating high-performance liquid chromatography must be obtained. It was found that pH had no influence on the a-arbutin or formulations' stability. All formulations had a-arbutin remaining higher than 90% (approximately 92%) after being stored for 60 days in all storage conditions with no significant changes in pH or visco...

Research paper thumbnail of Preparation of nanoemulsions by phase inversion temperature (PIT)

Pharmaceutical Sciences Asia, 2018

Nowadays, there is an increasing interest in the utilization of nanoemulsions in many industries,... more Nowadays, there is an increasing interest in the utilization of nanoemulsions in many industries, such as pharmaceuticals, food and beverage, cosmetics and agrochemicals because of a number of potential advantages over conventional emulsions (i.e., increased bioavailability, enhanced long-term stability and high optical clarity) and microemulsions (i.e., relatively low amount of surfactant used). The productions of nanoemulsions are typically divided into high-energy and low-energy emulsification methods. High-energy methods involve the use of mechanical devices to break up particles into smaller sizes. In contrast, lowenergy methods divert the intrinsic physicochemical properties of surfactants, co-surfactants and excipients in the formulation, leading to the generation of emulsion droplets in the nanometric range. Owing to the advantages of low-energy methods (i.e., low cost and ease of implementation), there is considerable interest in the productions of nanoemulsions using low-energy methods, namely spontaneous emulsification, phase inversion composition, and phase inversion temperature (PIT). Among these, the PIT method is the most widely used in industry and has evidenced the progress in the knowledge of the factors leading to nanoemulsions with minimum size and low polydispersity index. In this review, the principle of the PIT method is presented. The major factors influencing nanoemulsion formation using the PIT method and its applications to other lipid-based nanocarriers are reviewed.

Research paper thumbnail of Vegetable oil-based nanoemulsions containing curcuminoids: Formation optimization by phase inversion temperature method

Journal of Drug Delivery Science and Technology, 2018

Antiretroviral therapy and its major scaling up over the past decade has contributed to improving... more Antiretroviral therapy and its major scaling up over the past decade has contributed to improving the quality of life of people living with HIV, but the mortality associated with this pandemic remains a concern in our environment and opportunistic infections are the major causes of death in most patients. The objective is to determine the causes of patients' deaths living with HIV at the Lubumbashi University Center of Excellence. A documentary review of patients was conducted from May 2011 to December 2015. Death is considered HIV-related if it is the result of an opportunistic infection in any patient with CD4 less than 200/mm 3. 1717 patients were recruited to the center of excellence between May 2011 and December 2015, the mortality rate was 24.1% patient year, 67.95% women and 32.05% male 76.63% of patients had CD 4 less than 200 mm 3. 86% of the causes were directly related to HIV, Cryptococcal neuromeningitis comes first with 16.6%, while tuberculosis follows with 15.3%; 8% of the causes were not directly related to HIV, it is notably hepatopathies with 2.6%.

Research paper thumbnail of Enhanced supersaturation of chlortetracycline hydrochloride by amorphous solid dispersion

Journal of Drug Delivery Science and Technology, 2018

RESUMEN: Los hábitos deformantes orales son una de las principales causas de las maloclusiones, e... more RESUMEN: Los hábitos deformantes orales son una de las principales causas de las maloclusiones, entre los más frecuentes tenemos: la succión digital, el empuje lingual, la onicofagia, la queilofagia, la respiración oral y la masticación de objetos. El objetivo de este estudio fué efectuar una evaluación y análisis de la evidencia científica disponible actualizada en los últimos 7 años sobre los hábitos deformantes orales en preescolares y escolares de 3 a 12 años de edad. Se realizó una revisión sistemática de la literatura en bases de datos referativos como: Scielo, LILACS, GOOGLE ACADÉMICO, en artículos publicados sobre hábitos orales deformantes presentes en niños preescolares y escolares de 3 a 12 años de edad, con fechas de publicación que datan del 2010 al 2017, no hubo restricción en cuanto a sexo o zona geográfica. Se encontró una alta incidencia de hábitos deformantes orales en países de América latina, Centro américa y el Caribe; en países como Cuba la incidencia fue muy alta, el hábito que tuvo mayor prevalencia en la muestra fue la Onicofagia seguido de la disfunción lingual, resultados similares se reflejaron en países como Venezuela, México y Colombia. Los resultados de esta revisión evidencian la importancia del estudio de los hábitos deformantes orales, los cuales constituyen una de las principales causas de las maloclusiones, que a su vez son el tercer problema de salud bucodental. En su gran mayoría, de los artículos tomados como referencia demostraron que no existe una diferencia estadísticamente significativa respecto al sexo y la prevalencia de hábitos parafuncionales. Se destaca la importancia de implementar nuevos proyectos de investigación respecto a los hábitos parafuncionales en la población preescolar y escolar, acompañado de programas educativo en nuestro país Ecuador, ya que en la actualidad fueron pocas las publicaciones que pudimos tomar de referencia. PALABRAS CLAVE: hábitos orales deformantes, hábitos orales, dentición temporaria, dentición mixta, maloclusión.

Research paper thumbnail of Effect of binary solid lipid matrix of wax and triglyceride on lipid crystallinity, drug-lipid interaction and drug release of ibuprofen-loaded solid lipid nanoparticles (SLN) for dermal delivery

Journal of Colloid and Interface Science, 2017

Effect of binary solid lipid matrix of wax and triglyceride on lipid crystallinity, druglipid int... more Effect of binary solid lipid matrix of wax and triglyceride on lipid crystallinity, druglipid interaction and drug release of ibuprofen-loaded solid lipid nanoparticles (SLN) for dermal delivery,

Research paper thumbnail of Effect of Tripolyphosphate on Physical and Enzymatic Stabilities of Insulin Loaded Nanoparticles of N-Trimethyl Chitosan

The aim of the present work was to elucidate the influence of tripolyphosphate (TPP) on the collo... more The aim of the present work was to elucidate the influence of tripolyphosphate (TPP) on the colloidal and insulin stabilities. Using a trimethyl chitosan (TMC) with quaternization degree of 40%, insulin loaded nanoparticles were prepared by ionotropic gelation with TPP crosslinker. The nanoparticles were characterized for size, zeta potential, insulin loading, process yield, colloidal stability and the protection capability of insulin against enzymatic degradation of trypsin. The results showed that insulin nanoparticles were in the range of 200-260 nm with spherical or oval morphology. The highest insulin loading efficiency of nanoparticles with narrow size distribution was achieved when TPP:TMC:insulin mass ratio of 0.4:1:1 was used. The colloidal stability was TPP concentration dependent. The presence of TPP accelerated the degradation of free insulin and insulin loaded nanoparticles which increased with increasing TPP concentration. Therefore, the preparation of nanoparticles by ionotropic gelation with TPP would not be suitable for the development of insulin delivery system. ©All right reserved.

Research paper thumbnail of Nasal absorption and local tissue reaction of insulin nanocomplexes of trimethyl chitosan derivatives in rats

The Journal of pharmacy and pharmacology, 2010

The objective of this work was to explore the potential and safety of trimethyl chitosan (TMC) an... more The objective of this work was to explore the potential and safety of trimethyl chitosan (TMC) and PEGylated TMC for improved absorption of insulin after nasal administration. The nasal absorption of insulin nanocomplexes of TMC or PEGylated TMC was evaluated in anaesthetized rats. Concomitantly, the histopathological effects of these nanocomplexes on rat nasal mucosa were studied using a perfusion fixation technique. All insulin nanocomplexes containing TMC or PEGylated TMC showed a 34-47% reduction in the blood glucose concentration, when the insulin absorption through the rat nasal mucosa was measured indirectly. In addition, the relative pharmacodynamic bioavailability (F(dyn)) of the formulations was found to be dependent upon the charge ratio of insulin and polymer, regardless of polymer structure. The F(dyn) apparently decreased with increasing charge ratio of insulin : polymer. Although acute alterations in nasal morphology by the formulations were affected by the charge rat...

Research paper thumbnail of Influence of chemical penetration enhancers on skin permeability of ellagic acid-loaded niosomes

Asian Journal of Pharmaceutical Sciences, 2013

This study aimed to develop niosomes of ellagic acid (EA), a potent antioxidant phytochemical sub... more This study aimed to develop niosomes of ellagic acid (EA), a potent antioxidant phytochemical substance, for dermal delivery and to investigate the influence of chemical penetration enhancers on the physicochemical properties of EA-loaded niosomes. The EA niosomes were prepared by reverse phase evaporation method using Span 60, Tween 60 and cholesterol as vesicle forming agents and Solulan C24 as a steric stabilizer. Polyethylene glycol 400 (PEG) was used as a solubilizer while dimethylsulfoxide (DMSO) or Nmethyl-2-pyrrolidone (NMP) was used as a skin penetration enhancer. It was found that the mean particle sizes of EA-loaded niosomes were in the range of 312e402 nm with PI values of lower than 0.4. The niosomes were determined to be spherical multilamellar vesicles as observed by transmission electron microscope and optical microscopy. All niosomes were

Research paper thumbnail of Preparation of Virgin Coconut Oil Nanoemulsions by Phase Inversion Temperature Method

Advanced Materials Research, 2014

Presently, the low energy emulsification method; phase inversion temperature (PIT) method offers ... more Presently, the low energy emulsification method; phase inversion temperature (PIT) method offers a convenient mean of nanoemulsion formation for the incorporation of fragile substances. The aim of the current study was to prepare coconut oil nanoemulsions using cremophor RH 40 as nonionic surfactant in the light of PIT method. The suitable composition of coconut oil, cremophor RH40 and water was investigated by construction of ternary phase diagram. The PIT of system can be adjusted to 75 °C by adding NaCl at the concentration of 6%(w/w). Stable translucent nanoemulsions with particle size in range of 20-100 nm and PDI<0.2 can be formed at the constituent proportions of 5%-30%(w/w), coconut oil, 10%-80%(w/w) cremophor RH40 and 5%-85%(w/w) NaCl solution of 6%(w/w). All formulations were stable for up to 2 months when stored at 4, 30 and 40 °C and protected from light.

Research paper thumbnail of The role of mucoadhesion of trimethyl chitosan and PEGylated trimethyl chitosan nanocomplexes in insulin uptake

Journal of Pharmaceutical Sciences, 2009

The aim of this work was to investigate the role of mucoadhesion in the insulin uptake of nanocom... more The aim of this work was to investigate the role of mucoadhesion in the insulin uptake of nanocomplexes (NC) based of trimethyl chitosan (TMC) and poly(ethylene glycol) (PEG)-graft-TMC copolymers. Self-assembled insulin NC were prepared by polyelectrolyte complexation. The effects of PEGylation and positive charge density on mucoadhesion were assessed using a mucin assay and mucus-secreting HT29-MTX-E12 (E12) monolayers. The behaviors of corresponding insulin NC after adhesion to E12 were also established. All PEGylated TMC copolymers showed significantly higher levels of adhesion to mucus than unmodified TMC. The copolymer composed of 298 PEG chains per TMC macromolecules exhibited the highest level of mucoadhesion, being 3.4 times higher than TMC. The higher mucoadhesive properties of PEGylated TMC copolymers resulted from the synergistic effects of interpenetration of PEG chains into the mucus and electrostatic interaction between positive charged TMC and anionic glycoproteins present in the mucus layer. Compared to TMC, insulin NC based on PEGylated TMC copolymers demonstrated no evidence of insulin uptake improvement due to complete release of insulin from NC after adhering to mucus. CLSM revealed the localization of TMC and its corresponding insulin NC at cell surface membranes of E12.

Research paper thumbnail of Physicochemical properties and biocompatibility of N-trimethyl chitosan: Effect of quaternization and dimethylation

European Journal of Pharmaceutics and Biopharmaceutics, 2008

The aim of this research was to investigate the effect of degrees of quaternization (DQ) and dime... more The aim of this research was to investigate the effect of degrees of quaternization (DQ) and dimethylation (DD) on physicochemical properties and cytotoxicity of N-trimethyl chitosan (TMC). TMC was synthesized by reductive methylation of chitosan in the presence of a strong base at elevated temperature and polymer characteristics were investigated. The number of methylation process and duration of reaction were demonstrated to affect the DQ and DD. An increased number of reaction steps increased DQ and decreased DD, while an extended duration of reaction increased both DQ and DD. The molecular weight of TMC was in the range of 60-550 kDa. From the Mark-Houwink equation, it was found that TMC in 2% acetic acid/0.2 M sodium acetate behaved as a spherical structure, approximating a random coil. The highest solubility was found with TMC of an intermediate DQ (40%) regardless of DD and molecular weight. The effect of DD on the physicochemical properties and cytotoxicity was obviously observed when proportion of DD to DQ was higher than 1. TMC with relatively high DD showed reduction in both solubility and mucoadhesion and hence decreased cytotoxicity. However, the influence of DD was insignificant when DQ of TMC was higher than 40% at which physicochemical properties and cytotoxicity were mainly dependent upon DQ.

Research paper thumbnail of Peroral delivery of insulin using chitosan derivatives: a comparative study of polyelectrolyte nanocomplexes and nanoparticles

International journal of pharmaceutics, Jan 5, 2007

Polymeric delivery systems based on nanoparticles (NP) have emerged as a promising approach for p... more Polymeric delivery systems based on nanoparticles (NP) have emerged as a promising approach for peroral insulin delivery. Using a trimethyl chitosan (TMC) and a PEG-graft-TMC copolymer, polyelectrolyte complexes (PEC) and nanoparticles were prepared and their properties were compared. The amount of insulin was quantified by HPLC and the stability of PEC and NP upon exposure to simulated gastrointestinal (GI) fluid was monitored by dynamic laser light scattering. It was shown that polymer/insulin (+/-) charge ratio played an important role in PEC and NP formation. Stable, uniform, and spherical PEC/NP with high insulin association efficiency (AE) were formed at or close to optimized polymer/insulin (+/-) charge ratio, depending on polymer structure. All PEC were more stable in pH 6.8 simulated intestinal fluid (SIF) than NP. The PEC also appeared to play some role in protecting insulin from degradation at higher temperature and with proteolytic enzyme more efficiently than NP. On the...

Research paper thumbnail of Self-assembled polyelectrolyte nanocomplexes between chitosan derivatives and insulin

Journal of Pharmaceutical Sciences, 2006

Polyelectrolyte complexes (PEC) formed from chitosan derivatives and insulin was prepared and par... more Polyelectrolyte complexes (PEC) formed from chitosan derivatives and insulin was prepared and parameters influencing complex formation were characterized. Turbidimetric titration, in combination with dynamic light scattering (DLS) and laser doppler anemometry (LDA), were used to study the complexation process. The morphology of the PECs was determined using atomic force microscopy (AFM). PEC formation was predominantly pH-dependent. Complexation with insulin occurred only above critical pH value (pHc) of 6.0 for all the chitosan derivatives investigated. Soluble PECs in the size range of 200-500 nm with spherical or subspherical morphology and smooth surface structure were obtained at optimized polymer/insulin charge ratios. Optimal conditions were obtained when the pH of PECs was in the range of 6.5-8.0, depending on polymer structure. The stability of PECs was influenced by polymer chain length. Only when the MW of the polymers was !25-kDa PEC precipitation could be avoided. An increase in the ionic strength of the medium accelerated complex dissociation. Chitosan methylation and PEGylation significantly improved the stability of insulin in the PECs. Moreover, the PEC could protect insulin from degradation even at 508C for at least 6 h. All complexes could be lyophilized without influencing the particle size, complex concentration, and stability of insulin. On the basis of our results, we suggest that interactions involved in PEC formation were predominantly electrostatic in nature, involving the positively charged amino groups of chitosan and the negatively charged insulin above its isoelectric point. Intranasal absorption of the polyelectrolyte nanocomplexes will be studied in vivo.