No abstract

No abstract

Abstract. The purpose of this study was to investigate the nasal absorption of progesterone from carbopol-based nasal gels in rabbits. Progesterone nasal gels were prepared by dispersing carbopol 974 (1%, 1.5%, and 2%) in distilled water followed by addition of progesterone/progesterone-β cyclodextrin complex dissolved in propylene glycol then neutralization. The potential use of β cyclodextrin (CD) as nasal absorption enhancer by simple addition, as a physical mixture and as a complex with progesterone was investigated. The absolute bioavailability of progesterone from nasal gels in rabbits was studied by estimating the serum progesterone level by competitive solid-phase enzyme immunoassay in comparison to intravenous injection. The carbopol gel formulations produced a significant increase in bioavailability. CD complex promotes the nasal absorption of progesterone from carbopol gels as compared with gels where the CD is added by simple addition and gels which do not contain CD. This method of addition of CD as an inclusion complex in the gels could be considered as a preferred platform in nasal drug administration.

No abstract

This study investigates the preparation of colon specific drug delivery of diclofenac sodium (DS) using maltiparticulate system with chitosan phthalate (CP). Technique adopted to prepare sphere shaped multiparticulate system was extrusion and spheronization. The prepared pellets resulted with good spherical geometry with 1.1 ± 0.20 mm diameter. DS loaded system shows a maximum delivery pH of 7.4 and the same depressed at pH 1.2. The developed system significantly (p < .05) increase in the peak plasma concentration (C max ) of DS pellets when compared to that of pure DS. As expected the novel formulation showed a significant increase in oral bioavailability of DS for about three times. Additionally, the CP pellets of DS showed a momentous improvement in anti-inflammatory activity and reduced/ inhibited ulcer index. K E Y W O R D Schitosan phthalate, in vivo, pH dependent, sustained release

Rabeprazole sodium is highly acid-labile and presents many formulation challenges and to protect it from acidic environment of the stomach an enteric coated tablet formulation is tried in the present study. This study is aimed to develop pharmaceutically equivalent and stable enteric-coated tablets of Rabeprazole sodium comparable to innovator product. Different Formulations of Rabeprazole core tablets were developed using mannitol as diluent and croscarmellose as super disintegrant in different proportions. Further optimized formulation was coated with varying the compositions of sub coating and enteric coating using opadry white and enteric yellow. Compatibility studies were performed for drug, physical mixture tablet which shows no interaction. From the dissolution the formulation F6 shows highest percentage of drug release. The kinetics of drug release for F6 & Innovator followed first order and 'n' value (0.5>n<1) shows that the mechanism may be erosion control rate release. The f1 and f2 were found to be 3.03 and 72.01 respectively for formulation F6 and innovator product. Hence these two products were considered similar and comparable. In the accelerated stability testing carried out at 40°c and 75% RH for three months, no significant change in the physical properties, drug content, and dissolution rate of formulation F6 was observed. From this it can be concluded that formulation F6 developed is found to be an efficient delayed release formulations of Rabeprazole comparable to the innovator product. Thus the study fulfilled the objective of developing efficient Rabeprazole delayed release tablets.

The present paper deals with the development of silymarin entrapped Chitosan Phthalate (CP) nanoparticles for targeting colon cancer. The QbD approach is applied to optimize the silymarin loaded chitosan phthalate nanoparticles. DOE was employed to evaluate the dependent variables from the responses of CP nanoparticles. The CP NPs were found to be 140% of mucoadhesivity at pH 7.4, superior to pH 1.2 (10%). The result revealed the chemical or ionic bond formation between the positively charged amino groups of chitosan phthalate and the negatively charged sialic acid residue of mucin present in the mucous membrane. In vitro drug release profiles were carried out under acidic and basic pH conditions. The release of encapsulated silymarin was found to be poor in acidic conditions and maximum in basic conditions. The results suggested that chitosan phthalate nanoparticles could have the potential to enhance the bioavailability of silymarin.

Introduction: The purpose of this study was to formulate compression coated tablets of mesalamine and prednisolone for colon specific delivery and evaluate their in vitro and in vivo performances. Materials and Methods: Mesalamine is 5-amino salicylic acid used as a topical anti-inflammatory agent and prednisolone is a synthetic glucocorticoid used for the treatment of various types of inflammatory and autoimmune conditions. Pectin was used as an enzyme dependent polymer. Eudragit S 100 was used to enteric coat the compression coated tablets to avoid prerelease of the drug into the upper gastrointestinal tract. In vitro release study was carried out at various pH (1.2, 6.8 and 7.4) and in the presence of the pectinolytic enzyme. Therapeutic efficacy of the prepared tablets was evaluated in trinitrobenzene sulfonic acid-induced rabbit colitis model. Results: Formulation CF3c which was compression coated with of 150% of pectin and enteric coated with 7.5% Eudragit S 100 released 35.86% of mesalamine and 45.49% of prednisolone at the end of 7 h. The release increased significantly to 73.53% of mesalamine and 87.53% of prednisolone on addition of pectinolytic enzyme to the dissolution medium at the end of 10 h. Formula CF3c significantly reduced the inflammation of the treated group and the myeloperoxidase activity to 3.91 U/g. Conclusion: Studies demonstrated that orally administered compression coated tablets could be used effectively for the delivery of the drug to the colon.