Advanced Materials Research Vol. 506

Abstract: In this study, cationic liposomes prepared from egg phosphatidylcholine (PC) and novel spermine-based cationic lipids at a molar ratio of 5:1 were formulated. The chemical structures of these cationic lipids consisted of spermine head group and four hydrocarbon tails with differences in acyl chain (C14, C16 and C18). The effects of acyl chain and weight ratio of liposomes to DNA on transfection efficiency and cytotoxicity were investigated on a human cervical carcinoma cell line (HeLa cells) using the pDNA encoding green fluorescent protein (pEGFP-C2). The results from agarose gel electrophoresis illustrated that all cationic liposomes were able to condense with pDNA. The transfection efficiency of these cationic liposomes was in the following order: C18 (3,497±120 cells/cm²) > C14 (809±52 cells/cm²) > C16 (91±5 cells/cm²). The highest transfection efficiency was observed in the formulation of cationic liposomes with C18 tail at weight ratio of 15. In cytotoxicity studies, all formulations showed low cytotoxicity. In conclusion, these cationic liposomes containing novel cationic lipids (C18), showed promising potential as a gene carrier by efficient DNA condensation and mediated higher level of gene transfection.

Abstract: The aim of this study was to develop fluorescein sodium (NaFl) deformable liposomes with two different terpenes, d-limonene and 1,8 cineole, as skin penetration enhancer. NaFl was used as the model drug as it is a hydrophilic diagnostic agent, and has low skin penetration. The liposomes were prepared by reverse phase evaporation method. Their particle size, surface charge, and shape were characterized, in vitro skin penetration of NaFl through porcine skin were investigated. The obtained deformable liposomes were small particle size (<100 nm), negative charge and spherical shape. The liposome containing d-limonene provided the highest amount of NaFl followed by deformable liposomes with 1,8 cineole and conventional liposomes, repectively. The enhancement ratio of formulations containing terpenes were about 18-38fold compared with the conventional liposomes. These results indicated that the obtained deformable liposomes could be used as transdermal delivery of NaFl and incorporation of terpenes into deformable liposomes provided high efficiency for NaFl delivery through the skin.

Abstract: The objective of this study was to investigate the thermal property of thermal insulation board produced from admixtures of pineapple leaf fiber and natural rubber latex at different proportion level and the thermal property was evaluated based on the American Society for Testing Materials standard. Thermal insulation boards were fabricated using a hot pressing technique at a temperature of 150 °C under a pressure of 100 kg/cm² for 5 min to form a squared thermal insulation with the size of 35 cm and 0.9 cm thickness. The thermal conductivity of the thermal insulation was 0.057 W /m K with density of 338 kg/m³. The success of this study primarily proclaims a high feasibility of producing thermal insulation from pineapple leaf fiber and natural rubber latex as a substitute for synthetic fiber.

Abstract: The aim of this study was to investigate the effect of surfactants on characteristic and in vitro release of liposomes containing meloxicam (MX), model of water insoluble drug. The potential use of deformable liposomes for drug delivery system was developed and investigated. The formulation composed of constant amount of phosphatidylcholine (PC) and MX and various amounts of cholesterol (Chol), sodium cholate (NaChol), sodium oleate (NaO) and stearylamine (SA) was formulated by reverse phase evaporation method. The vesicle size, zeta potential, morphology, entrapment efficiency, loading efficiency, stability and in vitro release study were evaluated. The result indicated that the entrapment efficiency and in vitro release study of vesicle formulations containing surfactants were significantly higher than the conventional liposome and MX suspension. The formulation of 10:2:2:5 PC/MX/Chol/NaO provided the maximum entrapment efficiency and drug release. Our research suggested that MX loaded in deformable liposomes containing surfactants can be potentially used as a drug delivery carrier for water insoluble drug.

Abstract: 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.

Abstract: In the present study, methylated N-(4-N,N-dimethylaminocinnamyl) chitosan (TM65CM50CS) was synthesized and investigated for oral protein drug delivery by combining with liposomes entrapped bovine serum albumin (FITC-BSA), a model protein. FITC-BSA liposomes composed of egg yolk phosphatidylcholine and sodium oleate in molar ratio of 10:2 were prepared by thin film hydration method. The TM65CM50CS coated liposomal FITC-BSA was evaluated for transport of protein and its cytotoxicity in Caco-2 cells. Moreover, the in vitro stability of BSA in TM65CM50CS coated liposomes was also examined by the degradation of protein from pancreatin. The mean particle size and zeta-potential of liposomes were 101+0.02 nm and -27.44+2.02 mV, respectively. Initial FITC-BSA (2.5% w/w) to lipid showed the highest percentage entrapment efficiency (50.13%) and FITC-BSA content (8.08 mg/g of lipid). The results of FITC-BSA transport showed that TM65CM50CS coated FITC-BSA liposomes enhanced protein permeability across Caco-2 cell monolayers with low cytotoxicity. In addition, these liposomes could protect the degradation of protein from pancreatin. Our studies demonstrated that TM65CM50CS coated liposomes have the potential to be used as an oral protein drug delivery.

Abstract: The aim of this study was to prepare Caalginate and chitosan (CS)Caalginate microparticles for peroral delivery of ovalbumin (OVA). Microparticles containing different loading of OVA (10, 20 and 40 % w/w) were prepared by cross-linking alginate with calcium chloride using an electrohydrodynamic spraying technique, and then coated with CS. The particle sizes of OVA-loaded microparticles were in the range of 1-5 µm. The negative charge was obtained for Caalginate microparticles (-14±1.9 mV) whereas CSCaalginate microparticles were positive charge (+6.06±3.4 mV). Caalginate microparticles with initial 20% w/w OVA showed the highest entrapment efficiency and amount of OVA content (24.91±0.4% and 33.22±0.1 mg/g, respectively) as similar to CSCaalginate microparticles with initial 20% w/w OVA that showed the highest entrapment efficiency and amount of OVA content (35.74±0.1% and 10.35±0.5 mg/g, respectively). It was found that the release rate of OVA from Caalginate microparticles was higher than CSCaalginate microparticles, and the lowest release rate, sustained release for 24 h, was found in the initial 40% w/w OVA. This study revealed that CSCaalginate microparticles have a considerable potential as controlled release antigen delivery systems.

Abstract: This paper aimed to develop a physiologically activated dried antimicrobial spray for foot deodorant and select the suitable components such as film forming agent, solvent, antimicrobial agent and flavoring agents. The evaporation rates, antimicrobial activity, spray pattern, viscosity and cooling effect were evaluated. The developed formulation exhibited the high evaporating rate, high antimicrobial activity, appropriate spray pattern, slightly viscous solution with cooling effect after spraying onto skin. The developed formulation exhibited the potential application as the rapidly dried antimicrobial spray for foot deodorant.

Abstract: Porous polyethylene has been widely used for cranio-maxillofacial procedures due to its highly stable, flexible and has been shown to exhibit rapid soft-tissue and bone ingrowth. Generally, it is available as standard shape which needs to be intra-operatively contoured and manually adapted to fit the defect of each patient. In this study, a technique of producing customized porous polyethylene implant for calvarial defect reconstruction was reported. The technique began with acquiring patients data by computed tomography and was three dimensionally reconstructed using a medical imaging software. The shape of implant was then digitally designed to fit the defect based on the patients anatomy and transferred to three dimensional printing machine to fabricate the implant using proprietary polyethylene formulation as raw material. This technique can be used to cover any cranial defect size, offering similar or even better cosmetic results to standard alloplast cranioplasty while decreasing operation time. This customized porous implant can permit ingrowth of tissue to increase interface stability, implant strength and decrease the risk of infection similarly to commercial product.

Abstract: This work compares the ophthalmic delivery of vancomycin 50 mg/ml eye drops using 5 different vehicles, namely: 0.3% w/v chitosan, 0.3% and 0.4% w/v HPMC (Methocel E4M), Tears Naturale^TM II and 0.9% w/v sodium chloride solution. In vitro and in vivo studies were carried out and the results evaluated in terms of viscosity, compatibility, stability, clarity, minimum inhibitory concentration (MIC) and pharmacokinetics. The viscosity of Tears Naturale^TM II was comparable with that of HPMC (0.3% pH 7.1) but was higher than 0.3% w/v chitosan. The percent labeled amounts and MIC of vancomycin 50 mg/ml in all of the vehicles were stable for 30 days at 2-8°C, while the clarity in 0.3% w/v chitosan, 0.3% and 0.4% HPMC (pH 7.1), Tears Naturale^TM II and 0.9% sodium chloride solution was stable for 30, 14, 1 and 3 days respectively at 2-8°C. In vivo pharmacokinetic determinations of the AUC of tear film reciprocal of minimum inhibitory titer showed that vancomycin 50 mg/ml in 0.3% w/v chitosan, 0.3% and 0.4% w/v HPMC pH 7.1 and Tears Naturale^TM II were significantly different from 0.9% sodium chloride solution. At the present time, chitosan is undergoing clinical trials in Thailand with a view to its use in ophthalmology, while HPMC (0.3% w/v) in pH 7.1 has already been approved for use as a vehicle in ophthalmology for the delivery of vancomycin 50 mg/ml in extemporaneous eye drops.