Evaluation of Drug Release Kinetics of Temozolomide Loaded Plga Nanoparticles in Pluronic® F-127 Hydrogel

Objective:Controlled local release of temozolomide (TMZ) at the tumor site is a new strategy in the treatment of glioblastoma. Localized delivery systems, based on biodegradable polymers, are capable of slowing and controlling the drug release for a certain period of time. Therefore, the main objective of the study was to investigate a new approach for encapsulating TMZ in a poly(lactic-co-glycolic acid) nanoparticle (NP) system which was then formulated in 18% Pluronic® hydrogel matrix which would provide a sustained and local delivery of TMZ.Methods:Hydrogels are investigated as local drug delivery methods due to their tunable characteristics and capacity to retain labile pharmaceuticals. The lack of established procedures for describing and evaluating drug release, on the other hand, offers considerable problems, impeding reliable evaluation of systems for defining drug release characteristics.Results:In this part our study, we aimed to research drug release kinetics of TMZ NPs which had an encapsulation efficiency and particle size ranging between 52-69.67% and 164.4-235.5 nm from a novel hydrogel drug delivery system.Conclusion:The application of mathematical modeling proves to be extremely beneficial for estimating the release kinetics before the release systems are implemented. The release mechanism was found to be diffusion controlled and not accompanied by dissolution of matrix

Comparison of the Physicochemical Properties and Release Profiles of Metformin Tablets of Eight Different Brands Available in the Northern Cyprus Pharmaceutical Market

Objective:In the study, it was aimed to compare the physicochemical and in vitro dissolution parameters of metformin hydrochloride (MET) tablet brands from Northern Cyprus to evaluate the pharmaceutical equivalence.Methods:Seven brands of MET tablets which were bought from community pharmacies were compared and evaluated with the innovative product Glucophage®. The impurity of MET contained in the sample tablets was determined using Fourier transform infrared spectroscopy. Pharmacopoeia tests were used to evaluate the physicochemical equivalence of the tablets. In vitro dissolution test was performed and dissolution data were analyzed including dissolution difference (f1) and similarity factors (f2) were evaluated. In addition, the release kinetics of selected MET tablets were examined with a release kinetics software (KinetDS3).Results:All the tablet brands complied with the official specifications for uniformity of weight hardness and disintegration. Brand MF failed the friability test (>1%); while brands MC, MF and MG failed the content uniformity (assay) test (<95%). Difference (f1) and similarity factors (f2) of all brands were calculated in pH 6.8 buffer medium and evaluated with reference to the innovative brand. The facts that MB’s f1 value (15.45) was greater than 15 and that the f2 values of MB and MF (48.57, 47.13, respectively) were less than 50 indicated that the dissolution profiles of MB and MF formulations were different from the dissolution profile of the innovative brand.Conclusion:Five of the eight tablet brands passed all the official tests and could be regarded as pharmaceutically equivalent but f2 analysis showed only five brands were similar to the reference brand. The study has shown that all the MET tablet brands sampled in Northern Cyprus are not pharmaceutically equivalent