Usawadee Sakulkhu - Academia.edu (original) (raw)
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Papers by Usawadee Sakulkhu
2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems, 2007
ABSTRACT Solid lipid nanoparticles (SLNs) recently gain attention as colloidal drug carriers, for... more ABSTRACT Solid lipid nanoparticles (SLNs) recently gain attention as colloidal drug carriers, for both intravenous and dermal delivery. The present study focused on the preparation and some characterization of SLN associated with gamma-oryzanol of the specialized delivery systems. The nanoparticles, containing Dynasan 114 as lipid and Pluronicreg F68 as emulsifying agent were prepared by hot homogenization method. Particle sizes of SLNs were in suitable range and homogenous. Moreover, SLNs containing gamma-oryzanol are stable for investigated time as suggested by size, pH, % entrapment efficiency and DSC. Moreover, HPLC chromatograms indicated that no degradation was observed within the investigated period. Therefore chosen composition and method of preparation benefit the stability of the nanoparticles, which is suitable for transdermal skin penetration.
International Journal of Pharmaceutics, 2009
Nanotechnology, 2008
This present study was aimed at investigating the effect of the crystallinity of cetyl palmitate ... more This present study was aimed at investigating the effect of the crystallinity of cetyl palmitate based solid lipid nanoparticles (SLNs) on the physical properties of γ-oryzanol-loaded SLNs. SLNs consisting of varying ratios of cetyl palmitate and γ-oryzanol were prepared. Their hydrodynamic diameters were in the range 210-280 nm and the zeta potentials were in the range -27 to -35 mV. The size of SLNs increased as the amount of cetyl palmitate decreased whereas no significant change of zeta potentials was found. Atomic force microscopy pictures indicated the presence of disc-like particles. The crystallinity of SLNs, determined by differential scanning calorimetry and powder x-ray diffraction, was directly dependent on the ratio of cetyl palmitate to γ-oryzanol and decreased with decreasing cetyl palmitate content in the lipid matrix. Varying this ratio in the lipid mix resulted in a shift in the melting temperature and enthalpy, although the SLN structure remained unchanged as an orthorhombic lamellar lattice. This has been attributed to a potential inhibition by γ-oryzanol during lipid crystal growth as well as a less ordered structure of the SLNs. The results revealed that the crystallinity of the SLNs was mainly dependent on the solid lipid, and that the crystallinity has an important impact on the physical characteristics of active-loaded SLNs.
Journal of Microencapsulation, 2009
In the present study gamma-oryzanol, an antioxidant, was incorporated into three different types ... more In the present study gamma-oryzanol, an antioxidant, was incorporated into three different types of solid lipid: wax, triglycerides, a mixture of glycerides as solid lipid nanoparticles (SLN) and liquid lipid (Miglyol 812) as nanoemulsion (NE). Instability was found only from NE due to its significant increase in particle size and decreased entrapment efficiency (%EE) at a storage temperature of 45 degrees C. Solid lipid type in SLN plays an important role only on %EE, but not chemical stability. A decrease in crystallinity of SLN was observed with the incorporation of gamma-oryzanol and low recrystallization index were found with two glycerides-based SLN. The in vitro release studies demonstrated that a biphasic release pattern fitted well with the Higuchi model of SLN formulations. In comparison, nearly constant release was observed in NE comprised of similar composition. Wax-based SLN demonstrated the lowest cytotoxicity. NE, wax-based SLN and a mixture of glycerides-based SLN were considered to enhance the antioxidant activity of gamma-oryzanol.
HAL (Le Centre pour la Communication Scientifique Directe), Dec 19, 2014
Nanoparticles have a physical dimension comparable to the size of molecular structures on the cel... more Nanoparticles have a physical dimension comparable to the size of molecular structures on the cell surface. Therefore, nanoparticles, compared to larger (e.g., micrometer) particles, are considered to behave differently when they interact with cells. Nanoparticles in the Lung: Environmental Exposure and Drug Delivery provides a better understanding of how inhaled nanoparticles behave in the human lungs and body. Featuring contributions from renowned subject-matter experts, this authoritative text describes the sequence of events that nanoparticles encounter in the lungs when moving from the air into the bloodstream. This includes deposition, interactions with the alveolar surface and epithelium, translocation across the air–blood tissue barrier, and accumulation in the body. In addition, the book addresses practical considerations for drug delivery to the respiratory tract, drug and gene delivery in the lungs, and bio-nanocapsules. It considers the physicochemical, colloidal, and tr...
Biomaterials Science, 2015
We showed that protein corona is strongly dependent on the coating of the material.
RSC Adv., 2014
Novel, fast and reproducible way to obtain magnetic silica beads by PVA, silica and iron oxide na... more Novel, fast and reproducible way to obtain magnetic silica beads by PVA, silica and iron oxide nanoparticles cross-linking process.
Nanoscale, Jan 7, 2014
It is now well recognized that the surfaces of nanoparticles (NPs) are coated with biomolecules (... more It is now well recognized that the surfaces of nanoparticles (NPs) are coated with biomolecules (e.g., proteins) in a biological medium. Although extensive reports have been published on the protein corona at the surface of NPs in vitro, there are very few on the in vivo protein corona. The main reason for having very poor information regarding the protein corona in vivo is that separation of NPs from the in vivo environment has not been possible by using available techniques. Knowledge of the in vivo protein corona could lead to better understanding and prediction of the fate of NPs in vivo. Here, by using the unique magnetic properties of superparamagnetic iron oxide NPs (SPIONs), NPs were extracted from rat sera after in vivo interaction with the rat's physiological system. More specifically, the in vivo protein coronas of polyvinyl-alcohol-coated SPIONs with various surface charges are defined. The compositions of the corona at the surface of various SPIONs and their effects...
The Analyst, 2014
Magnetic susceptibility measurements allow the detection of magnetic nanoparticle (bio)distributi... more Magnetic susceptibility measurements allow the detection of magnetic nanoparticle (bio)distribution without any influence of coatings or endogenous metallic ions.
2007 2nd IEEE International Conference on Nano/Micro Engineered and Molecular Systems, 2007
ABSTRACT Solid lipid nanoparticles (SLNs) recently gain attention as colloidal drug carriers, for... more ABSTRACT Solid lipid nanoparticles (SLNs) recently gain attention as colloidal drug carriers, for both intravenous and dermal delivery. The present study focused on the preparation and some characterization of SLN associated with gamma-oryzanol of the specialized delivery systems. The nanoparticles, containing Dynasan 114 as lipid and Pluronicreg F68 as emulsifying agent were prepared by hot homogenization method. Particle sizes of SLNs were in suitable range and homogenous. Moreover, SLNs containing gamma-oryzanol are stable for investigated time as suggested by size, pH, % entrapment efficiency and DSC. Moreover, HPLC chromatograms indicated that no degradation was observed within the investigated period. Therefore chosen composition and method of preparation benefit the stability of the nanoparticles, which is suitable for transdermal skin penetration.
International Journal of Pharmaceutics, 2009
Nanotechnology, 2008
This present study was aimed at investigating the effect of the crystallinity of cetyl palmitate ... more This present study was aimed at investigating the effect of the crystallinity of cetyl palmitate based solid lipid nanoparticles (SLNs) on the physical properties of γ-oryzanol-loaded SLNs. SLNs consisting of varying ratios of cetyl palmitate and γ-oryzanol were prepared. Their hydrodynamic diameters were in the range 210-280 nm and the zeta potentials were in the range -27 to -35 mV. The size of SLNs increased as the amount of cetyl palmitate decreased whereas no significant change of zeta potentials was found. Atomic force microscopy pictures indicated the presence of disc-like particles. The crystallinity of SLNs, determined by differential scanning calorimetry and powder x-ray diffraction, was directly dependent on the ratio of cetyl palmitate to γ-oryzanol and decreased with decreasing cetyl palmitate content in the lipid matrix. Varying this ratio in the lipid mix resulted in a shift in the melting temperature and enthalpy, although the SLN structure remained unchanged as an orthorhombic lamellar lattice. This has been attributed to a potential inhibition by γ-oryzanol during lipid crystal growth as well as a less ordered structure of the SLNs. The results revealed that the crystallinity of the SLNs was mainly dependent on the solid lipid, and that the crystallinity has an important impact on the physical characteristics of active-loaded SLNs.
Journal of Microencapsulation, 2009
In the present study gamma-oryzanol, an antioxidant, was incorporated into three different types ... more In the present study gamma-oryzanol, an antioxidant, was incorporated into three different types of solid lipid: wax, triglycerides, a mixture of glycerides as solid lipid nanoparticles (SLN) and liquid lipid (Miglyol 812) as nanoemulsion (NE). Instability was found only from NE due to its significant increase in particle size and decreased entrapment efficiency (%EE) at a storage temperature of 45 degrees C. Solid lipid type in SLN plays an important role only on %EE, but not chemical stability. A decrease in crystallinity of SLN was observed with the incorporation of gamma-oryzanol and low recrystallization index were found with two glycerides-based SLN. The in vitro release studies demonstrated that a biphasic release pattern fitted well with the Higuchi model of SLN formulations. In comparison, nearly constant release was observed in NE comprised of similar composition. Wax-based SLN demonstrated the lowest cytotoxicity. NE, wax-based SLN and a mixture of glycerides-based SLN were considered to enhance the antioxidant activity of gamma-oryzanol.
HAL (Le Centre pour la Communication Scientifique Directe), Dec 19, 2014
Nanoparticles have a physical dimension comparable to the size of molecular structures on the cel... more Nanoparticles have a physical dimension comparable to the size of molecular structures on the cell surface. Therefore, nanoparticles, compared to larger (e.g., micrometer) particles, are considered to behave differently when they interact with cells. Nanoparticles in the Lung: Environmental Exposure and Drug Delivery provides a better understanding of how inhaled nanoparticles behave in the human lungs and body. Featuring contributions from renowned subject-matter experts, this authoritative text describes the sequence of events that nanoparticles encounter in the lungs when moving from the air into the bloodstream. This includes deposition, interactions with the alveolar surface and epithelium, translocation across the air–blood tissue barrier, and accumulation in the body. In addition, the book addresses practical considerations for drug delivery to the respiratory tract, drug and gene delivery in the lungs, and bio-nanocapsules. It considers the physicochemical, colloidal, and tr...
Biomaterials Science, 2015
We showed that protein corona is strongly dependent on the coating of the material.
RSC Adv., 2014
Novel, fast and reproducible way to obtain magnetic silica beads by PVA, silica and iron oxide na... more Novel, fast and reproducible way to obtain magnetic silica beads by PVA, silica and iron oxide nanoparticles cross-linking process.
Nanoscale, Jan 7, 2014
It is now well recognized that the surfaces of nanoparticles (NPs) are coated with biomolecules (... more It is now well recognized that the surfaces of nanoparticles (NPs) are coated with biomolecules (e.g., proteins) in a biological medium. Although extensive reports have been published on the protein corona at the surface of NPs in vitro, there are very few on the in vivo protein corona. The main reason for having very poor information regarding the protein corona in vivo is that separation of NPs from the in vivo environment has not been possible by using available techniques. Knowledge of the in vivo protein corona could lead to better understanding and prediction of the fate of NPs in vivo. Here, by using the unique magnetic properties of superparamagnetic iron oxide NPs (SPIONs), NPs were extracted from rat sera after in vivo interaction with the rat's physiological system. More specifically, the in vivo protein coronas of polyvinyl-alcohol-coated SPIONs with various surface charges are defined. The compositions of the corona at the surface of various SPIONs and their effects...
The Analyst, 2014
Magnetic susceptibility measurements allow the detection of magnetic nanoparticle (bio)distributi... more Magnetic susceptibility measurements allow the detection of magnetic nanoparticle (bio)distribution without any influence of coatings or endogenous metallic ions.