• Archives of Pharmacal Research
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• v.26 no.2
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• pp.162-167
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• 2003

Liquid suppository systems composed of poloxamers and bioadhesive polymers were easy to administer to the anus and mucoadhesive to the rectal tissues without leakage after the dose. However, a liquid suppository containing diclofenac sodium could not be developed using bioadhesive polymers. since the drug was precipitated in this preparation. To develop a liquid suppository system using sodium chloride instead of bioadhesive polymers, the physicochemical properties such as gelation temperature, gel strength and bioadhesive force of various formulations composed of diclofenac sodium, poloxamers and sodium chloride were investigated. Furthermore, the pharmacokinetic study of diclofenac sodium delivered by the liquid suppository was performed. Diclofenac sodium significantly increased the gelation temperature and weakened the gel strength and bioadhesive force, while sodium chloride did the opposite. The liquid suppositories with less than 1.0％ of sodium chloride, in which the drug was not precipitated, were inserted into the rectum without difficulty and leakage. Furthermore, liquid suppository gave significantly higher initial plasma concentrations and faster Tmax of diclofenac sodium than did solid suppository, indicating that drug from liquid suppository could be absorbed faster than that from solid one in rats. Our results suggested that a thermosensitive liquid suppository system with sodium chloride and poloxamers was a more physically stable, convenient and effective rectal dosage form for diclofenac sodium.

• Journal of Pharmaceutical Investigation
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• v.28 no.2
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• pp.99-107
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• 1998

The objective of this study was to develop effective oral formulations of rhEGF for gastric ulcer healing using polycarbophil. hydroxypropylcellulose(HPC) and sucralfate as its bioadhesive bases. Cytoprotective effects of rhEGF, cell proliferation and differentiation. on the ulcers induced by ethanol or acetic acid in rats were studied. rhEGF release from HPC formulation was much faster than that from polycarbophil formulation. HPC formulation combined with small amount of sucralfate showed much slower release of rhEGF than only HPC base only. rhEGF preparations with bioadhesive polymers showed better effects on the healing of gastric ulcers than EGF solution when administered orally. When rhEGF preparations were administered at once and the animals were under starvation, polycarbophil formulation showed better effect on gastric ulcers than HPC formulation. Otherwise, when rhEGF preparations were given more than three times and the rats were fed normally, HPC formulation showed good healing efficacy of ulcers compared to polycarbophil formulation. rhEGF showed dose-dependent effect on the healing of both chronic and acute ulcers.

• Journal of Pharmaceutical Investigation
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• v.27 no.2
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• pp.133-137
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• 1997

Buccal absorption test of omeprazole in human was performed to determine the permeability of the drug molecule through oral mucous membrane. Oral mucosal adhesive tablets of omeprazole were prepared by compressing the omeprazole with a mixture of sodium alginate and hydroxypropylmethyl cellulose (HPMC) as bioadhesive polymers, magnesium oxide (MgO) as a stabilizer and sodium carboxymethyl cellulose (Na CMC) or cros-carmellose sodium (Ac-Di-Sol) as disintegrants. The bioadhesive force, stability in saliva and release characteristics of the tablets were evaluated. Omeprazole was absorbed about 23% in 15 min through human buccal mucous membrane. Furthermore, omeprazole was stable in saliva for more than 8 hrs when MgO was added to the tablet as the amount of 2.5 fold of omeprazole. The release rate of omeprazole was increased with increasing the amount of sodium alginate in the tablet. From these results, it is suggested that tablets composed of [omeprazole/HPMC/sodium alginate/MgO/Ac-Di-Sol and/or Na CMC (20/6/24/50/10) (mg/tablet)] are potential candidate for buccal drug delivery system.

• Advances in Traditional Medicine
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• v.7 no.1
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• pp.51-64
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• 2007

Mucus is an aqueous gel complex with a constitution of about 95% water, high molecular weight glycoprotein (mucin), lipid, salts etc. Mucus appears to represent a significant barrier to the absorption of some compounds. Natural mucoadhesive agent was isolated and purified from the aqueous extract of the seeds of prosopis pallida (PP). Formulated tablet with the isolated material by wet granulation method. Some natural edible substances are in consideration for candidates as mucoadhesive agents to claim more effective controlled drug delivery as an alternative to the currently used synthetic mucoadhesive polymers. Subjected the materials obtained from natural source i.e. PP and standard synthetic substance, sodium carboxymethyl cellulose for evaluation of mucoadhesive property by various in vitro and in vivo methods. Through standard dissolution test and a model developed with rabbit, evaluated in vitro controlled release and bioadhesive property of theophylline formulation. Mucoadhesive agent obtained from PP showed good mucoadhesive potential in the demonstrated in vitro and in viνo models. The results suggest that the mucoadhesive agent showed controlled release properties by their application, substantially. In order to assess the gastrointestinal transit time in vivo, a radio opaque X-ray study performed in healthy rabbit testing the same controlled release formulation with and without bioadhesive polymer. Plasma levels of theophylline determined by the HPLC method and those allowed correlations to the in vitro mucoadhesive study results. Better correlation found between the results in different models. PP may acts as a better natural mucoadhesive agent in the extended drug delivery system.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.155-165
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• 1994

Some mucoadhesive polymers such as hydroxypropylcelluose (HPC) and carbopol-934 (CP) have been employed for the preparation of mucoadhesive polymeric systems, and their physical properties including mucoadhesion, swelling, and drug release were evaluated. A new simple experimental technique that can quantitatively measure the bioadhesive properties of various polymeric systems has been developed by the methods of detachment force test. As the polymeric systems, the discs of freeze-dried HPC/CP solid dispersions were prepared. The mucosa used in these tests were upper, middle, and lower parts of small intestine of male rats weighing $300{\sim}350\;g$. Detachment forces were increased as the mole fraction of CP increased in discs of HPC/CP solid dispersions. In the points of intestinal site dependence of mucoadhesion, the solid dispersions revealed non-specific mucoadhesion to the intestine. Swelling and drug release characteristics of mucoadhesive polymeric systems were studied extensively to find out the feasibility for the oral controlled delivery systems. Swelling ratio, expressed as the final height/initial height, has been determined in various pH buffer solutions. Hydrochlorothiazide (HCT) was employed as a model drug for release study. Apparent swelling and drug release rate constants, $K_s$ and $K_r$ respectively, were obtained from the square-root time plot of either swelling ratio or released amount of drug, particularly for the time periods before reaching the equilibrium. As a result, the swelling ratio of HPC/CP solid dispersions was increased as the weight percentage of CP increased. Similarly, the release of HCT from the solid dispersions was dependent on pH changes and CP contents, resulted in the slower release of HCT with the increases of pH and CP contents.

• YAKHAK HOEJI
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• v.42 no.2
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• pp.187-195
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• 1998

In order to ameliorate disadvantages of buccal ointments and mucoadhesive tablets used for the treatment of aphthosis, a thin mucoadhesive patch containing triamcinolone acetoni de was designed and evaluated for the pharmaceutical properties. The adhesive gel layer consisting of Noveon AA-1, hydroxypropylcellulose-M and ethylcellulose N 100, and the protective gel layer of ethylcellulose N 100, Eudragit RSPO and castor oil have been formulated and various properties such as viscosity of drug gel layer, thickness, in vitro adhesion time, adhesive strength, surface pH, content uniformity and drug release are tested. The mean viscosity of drug-containing gel layer was found to increase with increasing amount of Noveon OAA-1 or hydroxypropylcellulose-M. The optimum formulation showed the thickness of 171 ${\mu}$m, surface pH of 4.6, in vitro adhesion time of 8 hours and adhesive strength of 272.7g/sheet. The drug content of each patch was relatively homogeneous with the value of 273${\pm}$6.77g. Drug release study showed that compared to mucoadhesive tablet, the patch showed a faster drug release. Drug release was delayed by hydroxypropylcellulose-M, but not by ethylcellulose N 100. The patches prepared were nonirritant and the muco adhesion was better than the commercial product (AftachR) on the market. Based on these results, this mucoadhesive patch is expected to be an effective dosage form for the treatment of aphthosis.