Browsing by Author "Pojawon Lawanprasert"
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Item Metadata only Application of oil incorporating technique in formulation of hydrophobic drug microencapsulated beads(Mahidol University. Mahidol University Library and Knowledge Center, 2004) Santi Chunthatul; Pojawon LawanprasertPublication Metadata only Bioequivalence of indinavir capsules in healthy volunteers(2010-02-01) Suvatna Chulavatnatol; Kumthorn Malathum; Sasisopin Kiertiburanakul; Kittisak Sripha; Pojawon Lawanprasert; Mahidol University; Faculty of Medicine, Ramathibodi Hospital, Mahidol University; Faculty of PharmacyBackground: Indinavir, one component in the HAART regimen, plays an important role in the current treatment of HIV-infection and AIDS. Availability and accessibility of qualified generic indinavir to patients may be the keys for the success of treatment. Objective: Compare the rate and extent of absorption of a generic indinavir formulation with those of an original formulation in healthy Thai volunteers. Method: A randomized, two-period, two-treatment, two-sequence, crossover study with a two-week washout period was performed. A single dose of 2x400 mg indinavir capsules of each formulation was administered to 24 volunteers after an overnight fast. Indinavir plasma concentrations up to 10 hours postdose were determined using high-performance liquid chromatography. Relevant pharmacokinetic parameters were derived and tested for statistically significant differences using ANOVA and criteria of bioequivalence determination were applied. Results: No statistically significant differences were demonstrated for pharmacokinetic parameters including Cmax, Tmax, AUC0-t, and AUC0-8 derived from the two formulations (n=23, p>0.05). The criteria of bioequivalence determination i.e., the 90% confidence intervals on the mean ratio (generic/original formulation) of natural logarithmtransformed values of C max, AUC 0-t and AUC 0-∞ were 86.3-106.5%, 94.0-108.5%, and 93.9-108.5%, respectively. Conclusion: As the mean ratios of C max, AUC 0-t and AUC 0-∞ of the generic and original formulations were entirely within the guideline range of bioequivalence (80.0-125.0%), the two formulations were considered bioequivalent in terms of rate and extent of absorption.Item Open Access Effect of additives on physicochemical characteristics and stability of freeze-dried Cephalixin powder(1998) Satit Puttipipatkhachorn; Pojawon Lawanprasert; สาธิต พุทธิพิพัฒน์ขจร; Suwanthep, T; Mahidol Univesity. Faculty of Pharmacy. Department of Manufacturing Pharmacy; Pharmaceutical Association of Thailand; เภสัชกรรมสมาคมแห่งประเทศไทยItem Metadata only Effect of plasticizers on physicochemical properties of alginate film containing model drug(Mahidol University. Mahidol University Library and Knowledge Center, 2008) Yupin Mitpracha; Pojawon LawanprasertPublication Metadata only The influence of drug-excipient and drug-polymer interactions on butt adhesive strength of Ranitidine Hydrochloride film-coated tablets(2006) Narong Sarisuta; Pojawon Lawanprasert; Satit Puttipipatkhachorn; ณรงค์ สาริสุต; พจวรรณ ลาวัณย์ประเสริฐ; สาธิต พุทธพิพัฒน์ขจร; Krisana Srikummoon; Narong Sarisuta (e-mail: pynst@mahidol.ac.th); Mahidol University. Faculty of Pharmacy. Department of Manufacturing Pharmacy; Government Pharmaceutical Organization (Thailand). Production Division.The influence of fillers and polymeric films on adhesive strength of hydroxypropyl methylcellulose (HPMC) and Eudragit E100® films coated on ranitidine HCl tablets containing either spray-dried rice starch (SDRS) or lactose monohydrate as fillers after storage at 45°C/75% RH for four weeks was investigated by the use of butt adhesion technique. The adhesive strength of film-coated tablets of fillers without drug was found to slightly decrease after storage. In contrast, the adhesive strength of drug-containing film-coated tablets significantly reduced, the degree of which was higher for Eudragit E100® than HPMC. Physicochemical characterization by employing differential scanning calorimetry (DSC) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) revealed that the drug was obviously incompatible with lactose and possibly mild interaction with Eudragit E100® was suggested. The results indicated that the adhesive strength of film-coated tablets would be affected not only by the drug-excipient interaction, but also by the drug-polymeric film interaction.Publication Open Access Interaction of Amphotericin B with plastic intravenous administration set(2001) Pojawon Lawanprasert; Sorawit Pothikit; Narong Sarisuta; พจวรรณ ลาวัณย์ประเสริฐ; สรวิศ โพธิกิจ; ณรงค์ สาริสุต; Mahidol University. Faculty of Pharmacy. Department of Manafacturing PharmacyItem Metadata only Kinetic release of tramadol hydrochloride from hydrophilic swellable matrices containing two different directly compressible fillers(Mahidol University. Mahidol University Library and Knowledge Center, 2016) Mesamas Kanchanapan; Somboon Jateleela; Pojawon LawanprasertThe effects of mass fractions (mf) and types of polymer on the release kinetics of tramadol HCl (TMH) from hydrophilic swellable matrices were studied. Each formulation of the 500 mg tablet contains 200 mg TMH at a fixed mf of 0.40, polymer, i.e., hydroxypropylmethylcellulose (HPMC) K4M, K15M, xanthan gum (XG) or guar gum (GG) at an mf of 0.15, 0.30, 0.45 and 0.60, respectively, and dibasic calcium phosphate dihydrate (DCPD) or spray dried lactose (SDL) as a direct compression filler. Percentage drug release (Qi) was carried out in an USP dissolution apparatus type II in distilled water at various times (t) from 0 - 24 h. Qi of all formulations and the square root of time was shown to have a good linear relationship with a high regression constant that indicated that the drug release from the matrix tablets followed the Higuchi model of diffusion. The results showed that the type and mf of polymer and also the type of filler that could affect the rate constant (k), natural convection (Q0) and the lag time of TMH from matrix tablets. For various polymers used, XG provided the best retardability for drug release at all mf. For different fillers used, insoluble DCPD showed better retardability than SDL. The kinetics of TMH release from matrix tablets, using insoluble DCPD, was described by Shah et al model of diffusion, whereas those from matrices using soluble SDL was described by Jateleela et al model. From the calculation, using proposed equations in both models, most of the observed release profiles were closely fitted the predicted release profiles. Furthermore, the mechanisms of TMH transport from matrix tablets were described by the transport equation of Korsmeyer and Peppas. Matrices using GG provided quasi- Fickian diffusion, whereas most matrices using HPMC K4M or K15M provided non-Fickian transport, except matrices containing 0.15 either HPMC provided quasi-Fickian diffusion. For matrices using XG, the mf of XG, which changed the quasi-Fickian diffusion to non-Fickian transport was 0.60 XG for matrices containing DCPD and 0.45 XG for those containing SDL, respectively.Item Metadata only Permeability of biological membranes to model solutes(Mahidol University. Mahidol University Library and Knowledge Center, 2004) Sakchai Auychaipornlert; Pojawon LawanprasertPublication Metadata only Physical structure characterization of theophylline in some acidic film- forming polymers(2000-06-06) Narong Sarisuta; Mont Kumpugdee; Pojawon Lawanprasert; Mahidol UniversityThe physical structure and drug-polymer interactions of theophylline in Eudragit Ll00, shellac, polyvinyl acetate phthalate (PVAP), cellulose acetate phthalate (CAP), hydroxypropylmethylcellulose acetate phthalate (HPMCP), and hydroxypropylmethylcellulose (HPMC) were studied. The drug-polymer films were prepared by casting and were characterized using powder X-ray diffractometry (PXRD), nuclear magnetic resonance (NMR) spectroscopy, and thin-layer chromatography (TLC). Theophylline was found to recrystallize in the modification II form in all kinds of polymers, which was the same as that recrystallized solely from the solvent system and the original powder. The PXRD and NMR results indicated a superficial drug-polymer interaction between theophylline and Eudragit L100, while there was no evidence of interaction for the others. No drug decomposition was observed by TLC for all drug- polymer mixtures.Item Metadata only Preparation and evaluation of alginate-emulsion film using oil incorporating technique for use in drug delivery syystem(Mahidol University. Mahidol University Library and Knowledge Center, 2004) Adjchara Limpattanasiri; Pojawon LawanprasertItem Metadata only Preparation and evaluation of recrystallized lactose for dry powder inhaler(Mahidol University. Mahidol University Library and Knowledge Center, 2008) Akaraphon Nacornchai; Pojawon LawanprasertItem Metadata only The effects of adhesives on properties of ketoprofen patches(Mahidol University. Mahidol University Library and Knowledge Center, 2005) Rassamee Joradol; Panee Boonsaner; Pojawon LawanprasertTransdermal drug delivery system of ketoprofen was developed in this study. The aim of this study was to develop the transdermal drug delivery system that can reduce gastric irritation, dosing frequency and thus improve patient compliance. Ketoprofen patch was prepared by using acrylic as adhesive polymer matrix, mixture of ethanol as vehicle and Panasate 800 as enhancer in 50:50% w/w with 10%w/w of ketoprofen. The effects of class of acrylic adhesive (Duro-Tak® 87-2516, Duro-Tak® 87-2852 and Duro-Tak® 87-4098) and the concentration of acrylic adhesive (30%, 40% and 50% w/w) on skin permeation using human skin and adhesive properties were investigated. The results showed that the class of acrylic adhesive did not affect skin permeation but the adhesive properties by Duro-Tak® 87-2852 contained the highest peel and tack properties, followed by Duro-Tak® 87-2516 and Duro-Tak® 87- 4098 respectively. In addition, the skin permeation of the ketoprofen patches decreased when the concentration of acrylic adhesives increased. The same results were also found in adhesive properties, where peel and tack decreased when the concentration of acrylic adhesive increased. The drug permeation profile of ketoprofen from the patches followed Fick's equation, which indicated partition control. The results of this study indicated that the ketoprofen patch with 40% w/w of Duro-Tak® 87-2852 was the best formula. Compared with the commercial topical gel, this formula (B2) showed a higher permeation rate, however, the flux of drug permeation is lower composed with that theoretically indicated.Publication Open Access Utilization of Eeggshell powder as excipient in fast and sustained release acetaminophen tablets(2012) พจวรรณ ลาวัณย์ประเสริฐ; สมบูรณ์ เจตลีลา; Than, M.M.; Pojawon Lawanprasert; Somboon Jateleela; Mahidol University. Faculty of Pharmacy. Department of Manufacturing PharmacyEggshell powder has been investigated for the new application as pharmaceutical excipient in tablet dosage form. Acetaminophen was used as a model drug in this study. Four different eggshell powders were prepared. These included untreated eggshell powder, water treated, ethanol treated and chloroform treated eggshell powders. The treated samples were prepared by surface modification using 1.0 % w/v stearic acid in solvent namely deionized water, 95 % ethanol and chloroform. The tablets containing acetaminophen, eggshell powder and microcrystalline cellulose were prepared by direct compression method. Dissolution studies of four acetaminophen formulations in pH 5.8 phosphate buffer were performed using USP Dissolution Apparatus II. The results show that immediate release of acetaminophen was obtained from tablets containing untreated eggshell powder whereas sustained release of the drug was obtained from the tablet formulations containing three different treated eggshell powders. Sustained release of the drug may be due to hydrophobic nature of the treated eggshell powders. It was also found that the degree of hydrophobicity of the treated eggshell powders depends on the type of solvent used in surface modification process. The results obtained from this study show that eggshell powder appears to be applicable as a pharmaceutical excipient to control the drug release from the tablet. Additionally, this finding may be useful to generate public interest in development of biomaterials from eggshell waste by proposing the new application of eggshell powder in pharmaceutical industry.