A liposome is a spherical vesicle composed of phospholipids and cholesterol bilayer membrane and contains a core of aqueous solution. Liposomes are polymeric nanoparticles used for drug delivery due to their unique properties. It can carry both hydrophobic and hydrophilic molecules. In this study, we showed the benefit of using transmission electron microscope (TEM) with negative staining technique to investigate the morphology of liposomes produced by thin film method. At the same magnification of micrograph results, we could see the multilamellar vesicles of liposomes in various figures and different sizes.

The need for a topical drug delivery system of griseofulvin (GF) is dued to its poor oral bioavailability because of its low water solubility and excessively side effects. The preparation of griseofulvin-loaded into solid lipid nanoparticles (GF-SLNs) to nanometer range is expected to improve the dissolution rate by increasing the specific surface area. The aim of investigation was to produce griseofulvin-loaded into solid lipid nanoparticles by using a simple microemulsion technique, using glyceryl monostearate as solid lipid, polysorbate 20 as emulsifier, butanol and Transcutol HP®as co-emulsifiers. The GF-SLNs were evaluated for physical and chemical properties including GF release from GF-SLNs. The spherical particles were observed by TEM. The mean particle size of GF-SLNs was 165 nm and the zeta potential of GF-SLNs was -36 mV. There were interactions between GF and excipients in formula. The GF releasing profiles were obtained by a dialysis method with pH 5.5 phosphate buffer as medium, the release profile of GF was to be a prolong release of 63.53% within 12 hours.

The cracked heel is one of popular problems occurred within thai society. In this study, stick-formed preparation (ST) was developed for portability and convenient to use. The formula contained natural oil, coconut oil (C) or rice bran oil (R), for moisturizing purpose. It was found that 10% R giving a suitable hardness for ST. After addition of 5% salicylic acid (SA) in ST, its hardness was decrease. The modification of formula was performed to obtain a suitable hardness. The ability of moisture retaining (MR) from ST and commercial cream (CO) were evaluated at 32°C for 24 hr with 50% relative humidity, the result was shown that ST giving better MR than CO (P=0.0028). After 4 cycles of freeze-thaw stability study, the ST hardness was not significantly change (P>0.05). However, the amount of SA in ST from dissolution with Paddle over Disc method using acetate buffer pH 5.5 at 32°C was lower than in CO.

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The aim of this study was focusing on the excipients interaction especially between coloring agents and diluents. There were two coloring agents with different charges ; methylene blue(M) showing positive charge while amaranth(A) giving negative charge but all having same concentration of 0.1% w/w in each mixing batch. There are five types of starch using as diluents; arrowroot starch (W), rice starch (R), cassava starch (S), corn starch (C) and lesser yam starch (l). The physical properties of starch powder and paste (5%w/v) were evaluated as angle of repose and viscosity respectively. While the concentration of both coloring agents were determined by either UV spectroscopy or eye observation. The storage conditions of all samples were kept in both light and dark area for 7 weeks. It was found in powder form that C gave the most stable of M while R gave the worst for m in both light and dark condition. M showed less influences on flow properties of starches than a in a powder state. The flow of C with M gave the best results. The W paste was shown to be the most stable physical properties. M was suitable for S paste in a dark condition. While A was suitable for C, R and W paste in a light condition. The charges of coloring agents might not be a major influence on some physical properties of starch in both powder and paste form.