Chitosan-bovine serum albumin-Carbopol 940 nanogels for mupirocin dermal delivery: ex-vivo permeation and evaluation of cellular binding capacity via radiolabeling.

The goal of this study was to develop and examine the nanogel-based topical delivery system of mupirocin. Nanogels were prepared with chitosan and bovine serum albumin by ionic gelation and Carbopol 940 was added to improve the gelling/adhesive properties. Detailed characterization studies were performed and the cellular binding capacity of radiolabeled nanogels was investigated on CCD-1070Sk cell lines. Results indicate the successful formation of nanogels with particle size and zeta potential ranged between 341.920-603.320 nm and 13.120-24.300 mV, respectively. The mechanical and rheological studies proved pseudoplastic and strong elastic gel behavior (G' > G''). Mupirocin was successfully entrapped into nanogels with a ratio of more than 95% and the loaded drug was slowly released up to 93.89 ± 3.07% within 24 h. The ex vivo penetration and permeation percentages of mupirocin were very low (1.172 ± 0.202% and 0.161 ± 0.136%) indicating the suitability of nanogels for dermal use against superficial skin infections. The microbiological studies pointed out the effectiveness of nanogels against Staphylococcus aureus strains. Nanogels did not show toxicity signs and the cell binding capacity of radiolabeled formulations was found to be higher than [99mTc]NaTcO4 to CCD-1070Sk cell line. Overall, mupirocin nanogels might be considered as a potential and safe topical treatment option for bacterial skin infections.

Effect of microemulsion formulation on biodistribution of 99mTc-Aprotinin in acute pancreatitis models induced rats.

BACKGROUND: Aprotinin is a monomeric globular polypeptide, which derived from bovine lung tissue and theoretically attractive molecule in ameliorating the effects of acute pancreatitis. Acute pancreatitis is an inflammatory condition of the pancreas that is painful and at times deadly. Over the following two decades Aprotinin therapeutic potential on pancreatitis is proven experimentally, its clinical therapeutic success is limited due to low targeting to pancreas. OBJECTIVE: The aim of this study was to evaluate the biodistribution of Technetium-99m (99mTc)-Aprotinin solution (99mTc-Aprotinin-S) and 99mTc-Aprotinin loaded microemulsion, which was prepared for the aim of treatment for acute pancreatitis. METHOD: Aprotinin was radiolabeled with 99mTc. Radiochemical purity was determined with radioactive thin layer chromatography studies. 99mTc-Aprotinin-S and 99mTc-Aprotinin loaded microemulsion (99mTc-Aprotinin-M) was administered to acute edematous, severe necrotizing pancreatitis and air pouch model induced rats. Tissue distribution of Aprotinin was investigated with gamma scintigraphy and biodistribution studies. RESULTS: Aprotinin was radiolabeled by 99mTc with high radiochemical purity (95.430 ± 0.946%). The complex was found to be stable at room temperature up to 6 h. Animal studies have shown that similar to that of other small proteins Aprotinin is accumulated primarily in the kidney. The scintigraphy and biodistribution studies showed that, while i.v. administration of 99mTc-Aprotinin-S distributed mostly in kidneys and bladder, 99mTc-Aprotinin-M, with droplet size of 64.550 ± 3.217 nm, has high uptake in liver, spleen and pancreas. CONCLUSION: This might be concluding that microemulsions may be suggested as promising formulations for selectively targeting Aprotinin to pancreas inflammation.

Aprotinin revisited: formulation, characterization, biodistribution and therapeutic potential of new aprotinin microemulsion in acute pancreatitis.

The aim of this study was to develop aprotinin-loaded microemulsion (MA) for intravenous administration and evaluate the biodistribution and therapeutic potential of developed formulation in acute pancreatitis models in rats. Phase diagrams were constructed to identify microemulsion region and the optimal microemulsion was evaluated for physicochemical properties and treatment effect in rats, and comparisons made with the solution of aprotinin (SA). To evaluate the biodistribution of the drug by gamma scintigraphy aprotinin was radiolabeled with (99m)Tc radionuclide. Mild and severe acute pancreatitis was induced in rats by subcutaneous injections of cerulein and introductal infusion of 3% sodium taurocholate into the bile-pancreatic duct, respectively. In addition, serum amylase and pancreatic tissue myeloperoxidase activities were measured to evaluate the pancreatic damage. According to gamma scintigraphy and biodistribution studies, accumulation times and distribution of (99m)Tc-MA and SA were different. While MA was highly uptake by reticuloendothelial system, SA was mostly excreted by kidneys and bladder. Compared with the mild acute pancreatitis group, treatment with MA significantly decreased the serum amylase activity and pancreas myeloperoxidase activity. Furthermore, the protease inhibitor molecule aprotinin has therapeutic potential in acute pancreatitis. Finally, MA may be suggested as a promising alternative for treatment of acute pancreatitis.

In vitro evaluation of mucoadhesive vaginal tablets of antifungal drugs prepared with thiolated polymer and development of a new dissolution technique for vaginal formulations.

The main objective of this work was to develop antifungal matrix tablet for vaginal applications using mucoadhesive thiolated polymer. Econazole nitrate (EN) and miconazole nitrate (MN) were used as antifungal drugs to prepare the vaginal tablet formulations. Thiolated poly(acrylic acid)-cysteine (PAA-Cys) conjugate was synthesized by the covalent attachment of L-cysteine to PAA with the formation of amide bonds between the primary amino group of L-cysteine and the carboxylic acid group of the polymer. Vaginal mucoadhesive matrix tablets were prepared by direct compression technique. The investigation focused on the influence of modified polymer on water uptake behavior, mucoadhesive property and release rate of drug. Thiolated polymer increased the water uptake ratio and mucoadhesive property of the formulations. A new simple dissolution technique was developed to simulate the vaginal environment for the evaluation of release behavior of vaginal tablets. In this technique, daily production amount and rate of the vaginal fluid was used without any rotational movement. The drug release was found to be slower from PAA-Cys compared to that from PAA formulations. The similarity study results confirmed that the difference in particle size of EN and MN did not affect their release profile. The release process was described by plotting the fraction released drug versus time and n fitting data to the simple exponential model: M(t)/M(∞)=kt(n). The release kinetics were determined as Super Case II for all the formulations prepared with PAA or PAA-Cys. According to these results the mucoadhesive vaginal tablet formulations prepared with PAA-Cys represent good example for delivery systems which prolong the residence time of drugs at the vaginal mucosal surface.