Farahidah Mohamed - Academia.edu (original) (raw)

Papers by Farahidah Mohamed

KEYWORDS: INTRODUCTION: Malaysian Tualang Honey is a pure honey from combs of Asian honey bees (A... more KEYWORDS: INTRODUCTION: Malaysian Tualang Honey is a pure honey from combs of Asian honey bees (Apis dorsata) which build their hives high up in the Tualang tree (Koompassia excelsa). The objective of this work was to study the rheological properties ...

BACKGROUND: Osteoarthritis is a debilitating degenerative disease of the old age . One of the pat... more BACKGROUND: Osteoarthritis is a debilitating degenerative disease of the old age . One of the pathophysiology is that the synovial fluids (SF) are reduced due to the lowered concentration, reduced molecular weight of hyaluronic acid, thus reducing the viscoelasticity of the SF. Apart from the pharmacological treatments, intraarticular injection of hyaluronic acid (IAHA) was introduced as a viscosupplement in osteoarthritic patients to restore the viscoelasticity of the synovial fluids, give symptomatic relief of joint pain and delay the total joint arthroplasty. OBJECTIVE: To evaluate the viscosity and viscoelasticity of osteoarthritic SF with the aim to compare with IAHA; Synvisc (high molecular weight IAHA) and Suplasyn (low molecular weight IAHA). MATERIALS AND METHOD: The osteoarthritic SF was obtained from consented patients undergone total knee arthroplasty. The viscosity and the viscoelasticity of IAHA and osteoarthritic SF were analyzed at different temperatures (25, 37 and 40°C) using ThermoHaake rheometer. RESULTS: The flow curves constructed showed that osteoarthritic SF and both IAHA exhibited non-Newtonian shear thinning (pseudoplastic) fluid behaviour. The osteoarthritic SF had the lowest viscosity compared to IAHA. By increasing the temperatures, the viscosity of the IAHA and osteoarthritic SF were reduced. In the viscoelasticity test, the storage/elastic modulus of osteoarthritic SF and Synvisc were more dominant than the loss/viscous modulus. Unlike Suplasyn, the viscous modulus was more pronounced than the elastic modulus in all temperatures. CONCLUSION: At human body temperature, 37°C, both viscosupplements and osteoarthritic synovial fluids shared the same pseudoplastic type of non-Newtonian fluid. Synvisc and osteoarthritic SF showed elastic like behaviour more prominent than the viscous like behaviour opposite to Suplasyn. The rheological behaviour of Suplasyn and Synvisc with osteoarthritic SF were different because of the differences between the molecular weight of the hyaluronic acid and the network forming ability.

Current pharmacological treatments for osteoarthritis are analgesics and intraarticular injection... more Current pharmacological treatments for osteoarthritis are analgesics and intraarticular injection of hyaluronic acid (IAHA). Rheological measurements were performed on the viscosupplements to evaluate viscosity and dynamic responses with the aim to compare Synvisc (high molecular weight IAHA) with Suplasyn (low molecular weight IAHA). Both are widely used in the conservative treatment of osteoarthritis. The viscosity and dynamic rheology were analysed at different temperatures (25, 37 and 40°C) using ThermoHaake rheometer. The dynamic oscillatory testing was used to measure the storage modulus (G') and the loss modulus (G") of IAHA within the linear viscoelastic region. Suplasyn and Synvisc behaved as non-Newtonian shear thinning fluids (pseudoplastic flow type) however Synvisc showed higher viscosity compared to Suplasyn. By increasing the temperatures, the viscosity of the IAHA were reduced. In the dynamic oscillatory testing for viscoleasticity, the LVR of Synvisc was within 0.01-100Hz, meanwhile 0.1-10Hz for Suplasyn. The length of the LVR represented the stability of the microstructure of IAHA, and Synvisc was more stable than Suplasyn. The storage modulus of Synvisc was more than the loss modulus (G'>G") in all temperatures. The elastic like behaviour was more dominant in Synvisc compared to viscous like behaviour. Unlike, Suplasyn, the viscous like behaviour was more pronounced than the elastic like behaviour by showing the loss modulus was more than the storage modulus (G”>G’) in all temperatures. At human body temperature, 37°C, both viscosupplements shared the same pseudoplastic type of non-Newtonian fluid and shear thinning behaviour. However, Synvisc is more elastic compared to Suplasyn probably may be due to its higher molecular weight and cross linking properties.

Malaysian Journal of Microbiology, 2015

Aims: Accurate diagnosis and proper treatments of osteomyelitis are often difficult and ineffecti... more Aims: Accurate diagnosis and proper treatments of osteomyelitis are often difficult and ineffective due to several reasons such as less sensitive sample collected and the formation of biofilm following prosthetic use. Thus, our goal of this study is to identify suitable sample for laboratory diagnosis and also microbial species that cause osteomyelitic infection and discriminate between biofilm and non-biofilm producing strains in patients at Hospital Tengku Ampuan Afzan, Kuantan. Methodology and results: Samples of bone, prosthetic material, tissue and swab were collected from patient with suspected osteomyelitis at the hospital. Bacteria were isolated from sample using methods such as homogenization, direct transfer, and sonication. Then, species identification was done by colony characterization, biochemical test and the API identification system. Once species identified, tissue culture plate method was performed to discriminate the biofilm-producing strain from the non-biofilm-producing strain. The total number of 57 samples were collected from 17 cases of suspected osteomyelitis with 34 samples were found positive bacterial growth. Prosthetic samples produced highest positive growth with 81.3%, following by bone samples with 66.7% while swab and tissue samples with 46.2% and 43.8% respectively. We found that 14 from total 16 pathogens identified were biofilm producing-strains. Conclusion, significance, and impact of study: Prosthetic and bone samples produced higher bacterial growth, in contrast to other type of samples. Sonication method improves bacterial detection. Biofilm producing-bacteria were also the most common isolated strains from osteomyelitic infection. These have underscored the need to revise current clinical and laboratory practice as proper identification biofilm bacteria may influences management an outcome.

Thymoquinone (TQ) is the main active compound in black seed oil (BSO) which has unacceptable tast... more Thymoquinone (TQ) is the main active compound in black seed oil (BSO) which has unacceptable taste. Many reports confirmed that TQ has medical uses, but very few reports have documented its quantification or stability after formulation. In addition, stability of pure TQ under different conditions was studied to confirm that TQ was unstable in aqueous solutions, especially under alkaline environment. On the other hand, it is rarely to find reports about stability of TQ in BSO or BSO formulations. However, one of the most strongly used excipient in taste masking and improvement stability of the active compounds is alginate which can fabricated as beads in the presence of calcium ions.This study aimed to encapsulate BSO in alginate beads, and then to study stability of TQ in both forms of BSO and BSO-alginate beads.BSO-alginate beads were fabricated in 1% w/v calcium chloride bath. Concentration of BSO in the beads was 15% w/w. Aqueous solution of TQ, BSO, and BSO-alginate beads were packed in glass containers, well closed and stored at 40°±2°C /75±5% RH for 30 days. After specific time intervals (0, 15, and 30 days), the TQ content was analysed by using HPLC.The results indicated a poor stability of TQ in aqueous solution. Concentration of TQ in the aqueous solution was significantly (p0.05) decreased from 97.290.33 µg/mL at day 0 to 56.800.08 µg/mL at day 30. Moreover, concentration of TQ extracted from BSO showed a significant decreasing (p0.05) from 2.11±0.02% at day 0 to 1.95±0.005% at day 30. On the other hand, the stability of TQ in alginate beads containing BSO was highly improved (p0.05), (1.65±0.03% at day 0 and 1.58±0.04% at day 30). TQ in BSO may undergo some oxidation reaction during the period of storage in the stability chambers resulting in TQ degradation. On the other hand, alginate beads act a barrier against TQ oxidation, prolonging its shelf-life. This study suggests that BSO-alginate beads are stable in term of active principle and can be used as a source to provide TQ due to the unsuitability of aqueous solutions to formulate TQ

Supercritical carbon dioxide (SC-CO 2) extraction of fucoxanthin is more advantageous over conven... more Supercritical carbon dioxide (SC-CO 2) extraction of fucoxanthin is more advantageous over conventional solvent extraction as it is less toxic, less hazardous to the environment and preserves the bioactivity of fucoxanthin. A face-centered central composite design (FCCCD) based on response surface methodology (RSM) was employed for SC-CO 2 extraction of oils and fucoxanthin from the brown seaweed Sargassum binderi, with ethanol as a co-solvent. Three independent parameters namely, extraction temperature (A: 40, 50, 60 o C), pressure (B: 2900, 3625, 4350 psig and particle size (C: 90, 500 and 1000 µm) were investigated to optimize extraction oil yields (EOY) and fucoxanthin yields (FY). A regression model was developed, tested for quality of fit (R 2) and expressed in the form of 3D response surface curve and 2D contour. The optimum extraction conditions were obtained at extraction temperature (A) 50 o C, pressure (B) 3625 psig and particle size (C) 500 µm. Under these conditions, optimal EOY and FY were 10.04 mg/g and 3188.99 µg/g, respectively. The difference between the lowest and the highest response in EOY and FY were 5.44-10.04 mg/g and 2109.10-3188.90 µg/g, respectively. The lowest yields were identified at 60 o C, 2900 psig and 1000 µm. The regression models generated showing interactions between the variables and EOY and FY response were significant as tested by ANOVA (p < 0.0005 and p < 0.0007, respectively) with high R 2 values (0.9848 and 0.9829, respectively). Interactions between the parameters had a strong synergistic effect on EOY and FY values, as indicated by the 3D response surface curve and 2D contour. The experimental results matched the predicted results closely. This indicated the suitability of the models developed and the success of FCCCD under RSM in optimizing the S. binderi extraction conditions.

Analytical Chemistry Letters

International Journal of Pharmaceutical Investigation, 2012

Nonviral gene delivery system Gene therapy has been investigated a lot in both basic research and... more Nonviral gene delivery system Gene therapy has been investigated a lot in both basic research and clinical trials. [1] The first antisense oligodeoxyribonucleotide (ODN) drug, Vitravene (Fomivirsen), was approved by the United States Food and Drug Administration (FDA) in 2005. [2] After this approval, more and more clinical trials are conducted, not only for ODNs, but also for other nucleic acids drugs, such as plasmid vectors and small interference RNAs (siRNAs).

Frontiers in Pharmacology

Supramolecular mesoporous silica nanoparticles (MSNs) offer distinct properties as opposed to mic... more Supramolecular mesoporous silica nanoparticles (MSNs) offer distinct properties as opposed to micron-sized silica particles in terms of their crystal structure, morphology–porosity, toxicity, biological effects, and others. MSN biocompatibility has touched the pharmaceutical realm to exploit its robust synthesis pathway for delivery of various therapeutic molecules including macromolecules and small-molecule drugs. This article provides a brief review of MSN history followed by special emphasis on the influencing factors affecting morphology–porosity characteristics. Its applications as the next-generation drug delivery system (NGDDS) particularly in a controlled release dosage form via an oral drug delivery system are also presented and shall be highlighted as oral delivery is the most convenient route of drug administration with the economical cost of development through to scale-up for clinical trials and market launch.

Pre-formulation study is the main phase of drug development. At the early stage of pre-formulatio... more Pre-formulation study is the main phase of drug development. At the early stage of pre-formulation study, characterization has a significant role in determining the physical and chemical properties of a drug candidate. The physicochemical parameters conducted in this study were determination of pH, particle size analysis and solubility test in different type of solvents. Results of the determination of pH showed (pH of 5.69) indicating acidic. In particle size analysis, the numerous distribution of resin was 5.58% (highest peak) where the particle’s diameter range from 105.24µm to 117.13µm. The resin was slightly soluble in hot water, but insoluble in other solvents for the solubility test. This exact identification could elucidate the physical and chemical composition present in Inggu

Revon Media Sdn Bhd, Nov 1, 2021

Journal of Food Engineering, 2022

Tropical Journal of Pharmaceutical Research, Nov 14, 2017

International Journal of Advanced Research, 2018

INTRODUCTION: Black seed oil (BSO) is known for its wide range of therapeutic and prophylactic ap... more INTRODUCTION: Black seed oil (BSO) is known for its wide range of therapeutic and prophylactic applications, but it has pungent and bitter taste. In this research, BSO was encapsulated within wet and dried alginate beads to mask the unpleasant taste of the oil. OBJECTIVES: The aim of this study is to evaluate the palatability of the beads in terms of smell, taste, after taste, texture, and taste masking efficiency of the beads in adult volunteers. METHODS: Total of six volunteers were involved in palatability test. Five-point Likert scales were used to assess all aspects of the palatability. Volunteers were also asked to give taste score, i.e. how strong they feel the taste of the beads (from 0 to 100), considering BSO liquid as 100. RESULTS: Encapsulation in alginate beads with both form of wet and dried beads significantly improved the oil properties of smell, taste and the aftertaste feeling in addition to the ability of taste masking (p 0.05). Encapsulation of BSO in alginate be...

As conventional drug delivery system is being improved rapidly by target-based drug delivery syst... more As conventional drug delivery system is being improved rapidly by target-based drug delivery system, finding suitable Drug Delivery System (DDS) for new drugs remains a challenge. Although there are many drug delivery vehicles in existence, a significant improvement is required to some DDS such as for local, implant-based treatments used for musculoskeletal infections. Many polymers have been considered for providing the improvement in DDS. Synthetic polymer, for example, has gained popularity for broad-spectrum physicochemical and mechanical properties. This article reviews the biomedical applications of poly(TriMethylene Carbonate-co-Caprolactone) (PTMCC), which has attracted attention due to its biocompatibility, biodegradability and rubber-like properties. Its synthesis, physical properties, and degradation are also discussed here. Although it is relatively new in biomedical applications, it is readily usable for the fabrication of differing format of DDS of superior mechanical strength and degradation properties. The use of PTMCC is expected to increase in coming years as more is revealed about its potentials