Preliminary spectroscopic characterization of PEGylated mucin, a novel polymeric drug delivery system

The objective of this study was to evaluate, spectrophotometrically, the compatibility of non-mucinated polyethylene glycol (PEG) 4000 and non-PEGylated mucin in a PEGylated mucin matrices for drug delivery application. Mucin was extracted from the giant African land snails (Archachatina maginata) using chilled acetone and characterized in terms of qualitative properties and solubility profile. Polymeric matrices composed of PEG 4000 and mucin in ratios of 2:0 (A), 1:1 (B), 2:1(C) and 3:1 (D) were prepared by co-precipitation using chilled acetone. The matrices were characterized with respect to compatibility using the Fourier transform infrared (FT-IR) spectroscopy. Results of the qualitative tests performed on the snail mucin showed that carbohydrates, proteins and trace amounts of fats were present; the extracted mucin was light-brownish in colour, with a pleasant meaty odour. Snail mucin, when dispersed in water yielded a slightly viscous dispersion, but is not soluble in ethanol, acetone, 0.1 M sodium hydroxide, ammonium hydroxide and sulphuric acid. The presence of different peaks in the FT-IR spectra of the PEGylated mucin matrices compared with the non-PEGylated mucin (2:0) matrix and non-mucinated PEG 4000 (0:2) matrix indicated the formation of new polymers, which could be employed in drug delivery. This study has shown that PEGylation of mucin gives rise to new polymeric system with principal FT-IR peaks quite different from those of non-PEGylated mucin and nonmucinated PEG, and this may be employed in the delivery of drugs.Key words: PEGylation, drug delivery, mucin, Fourier transform infrared (FT-IR) spectroscopy, Archachatina maginata

Pharmacokinetics and biodistribution of zidovudine loaded in a solidified reverse micellar delivery system.

The aim of the research was to study the stability, release profile, pharmacokinetic and biodistribution properties of zidovudine (AZT)-solidified reverse micellar microparticulate. Lipid matrices formulated with Phospholipon® 90H and goat fat at ratios of 1:1, 2:1, 3:1 and 2:3 were used to prepare AZT-loaded SLM by melt dispersion followed by lyophilization. In vitro release studies of the drug were carried out using a sequential drug release method in both SGF (pH 1.2) and SIF (pH 7.2) while the in vivo drug release studies were carried out using Wistar albino rats. The result of our findings showed that the drug is compatibility with the lipid matrix with the 1:1 showing the most stable microparticle preparation which was then optimized. The formulations showed a concentration dependent increase in their concentration maximum (Cmax) with values of 116.05 µg/ml, 124.21 µg/ml, 128.95 µg/ml, 138.95 µg/ml and time to reach maximum concentration (Tmax) values of 5h, 8 h, 8 h, and 5 h for batches B1, B2, B3 and B4 containing 1 %, 2 %, 3 % and 5 % of AZT respectively. The area under curves (AUCs) of the microparticles formulated showed that the bioavailabilities of the microparticles were comparable to that of the conventional release tablet. The biodistribution studies of the microparticles in rats showed highest concentration of the drug in the liver with the least in the brain and higher biodistribution in various organs than pure AZT. The data suggested that SLM could be a promising drug delivery system to improve on the shortcomings of pharmacokinetics and bio-distribution properties of conventional AZT tablets like fluctuation in blood levels of the drug