Engineered PLGA microspheres for extended-release of naltrexone: in vitro, in vivo, and IVIVR.

Poly(lactide-co-glycolide) (PLGA)-based formulation is one of the most often used parenteral extended-release forms to deliver various therapeutics. VIVITROL® as a commercialized PLGA microsphere formulation encapsulates naltrexone, a narcotic antagonist for opioid addiction and alcohol dependency. However, no U.S. Food and Drug Administration-approved generic product of naltrexone PLGA microsphere formulation has entered the market. The availability of generic naltrexone PLGA microspheres in low-income countries will broaden patients' accessibility to the safe, effective, and more affordable drug. A major challenge in developing such generic forms is the sensitivity of the drug-loaded microspheres' critical characteristics to the small manufacturing changes, even in formulations with the same compositions as the reference product. In this study, we evaluated the different key manufacturing parameters on the physicochemical, in vitro and in vivo release characteristics of naltrexone microspheres to develop a generic form of naltrexone PLGA microspheres. The selected formulations demonstrated a significant similarity in physicochemical characteristics and release profiles (f2 > 50) to the reference product, VIVITROL®. A strong relationship was observed between in vitro release profile of naltrexone as against its corresponding in vivo profile. It helped to roughly predict the in vivo release behavior of the different manufactured formulations by their corresponding in vitro release profiles.

Glutamate-urea-based PSMA-targeted PLGA nanoparticles for prostate cancer delivery of docetaxel.

Targeted drug delivery is a tool to make treatment more specific, selective, and effective and to prevent unwanted complications. Prostate specific membrane antigen (PSMA) is a useful biomarker in order to monitor and control prostate cancer. Glutamate-Urea-R (Glu-Urea-R) is a PSMA enzyme inhibitor capable of binding to this surface marker of prostate cancer cell in an efficient and special manner. The aim of this project was to develop a docetaxel-loaded nanoparticle of poly (lactic-co-glycolic acid) polyethylene glycol which is cojugated to a urea-based anti-PSMA ligand named glutamate-urea-lysine (glu-urea-lys) for targeted delivery of docetaxel in prostate cancer. The obtained nanoparticles, prepared by nanoprecipitation method, were spheres with a particle size of around 150 nm and zeta potential of -7.08 mV. Uptake studies on the PC3 (as PSMA negative) and LNCaP (as PSMA positive) cells demonstrated that drug uptake was efficient by the PSMA positive cells. IC50 of targeted NPs on LNCaP cell line compared to non-targeted ones was reduced by more than 70% in three different incubation times of 24, 48, and 72 h. In conclusion, the nanoparticles are expected to specifically transport docetaxel to PSMA-positive prostate cancer cells and consequently, enhance the antitumor efficacy of docetaxel on these cells.

Spectrophotometric Methods for Determination of Sunitinib in Pharmaceutical Dosage Forms Based on Ion-pair Complex Formation.

Three rapid spectrophotometric methods were developed for the determination of sunitinib based on the formation of ion-pair complex in acidic medium with bromocresol purple, bromothymol blue, and bromophenol blue. The formed ion-pair complexes, extractable with chloroform, were measured at 422 nm for bromocresol purple, 425 nm for bromothymol blue and 427 nm for bromophenol blue. All these methods were optimized for the pH of buffer and the volume of the reagent. The methods were linear over the range of 1-200 µg/mL for bromocresol purple, 1-150 µg/mL for bromothymol blue, and 2-200 µg/mL for bromophenol blue with a very low limit of quantification and acceptable accuracy and precision. Using the proposed methods for determination of sunitinib in pharmaceutical dosage forms showed reliable results comparable to previously published method.

Fabrication and biological evaluation of chitosan coated hyaluronic acid-docetaxel conjugate nanoparticles in CD44(+) cancer cells.

BACKGROUND: Hyaluronic acid (HA) has been used for target-specific drug delivery because of strong affinity to CD44, a marker in which overexpressed in cancer cells and cancer stem cells. Conjugation of HA to the cytotoxic agents via active targeting can improve efficacy, biodistribution, and water solubility. To be able to benefit from passive targeting as well, a nanoparticulate system by counter ion using a polycation like chitosan may lead to a perfect delivery system. METHODS: Water soluble Hyaluronic acid-Docetaxel (HA-DTX) conjugate was prepared and used to formulate chitosan-coated HA-DTX nanoparticles by polyelectrolyte complex (PEC) method and optimized using Box-Behnken design. Biological evaluation of nanoparticles was done in CD44+ cancer cells. RESULTS AND DISCUSSION: Biological evaluation of optimized formula showed IC50 of nanoparticles for 4 T1 and MCF-7 cell lines were 45.34 µM and 354.25 µM against 233.8 µM and 625.9 µM for DTX, respectively with increased cellular uptake showed by inverted confocal microscope. CONCLUSION: Chitosan-coated HA-DTX nanoparticles were more effective against CD44+ cells than free DTX. Chitosan coated hyaluronic acid-docetaxel conjugate nanoparticles fabricated and evaluated in CD44+ cancer cells.

Development of a rapid derivative spectrophotometric method for simultaneous determination of acetaminophen, diphenhydramine and pseudoephedrine in tablets.

A mixture of acetaminophen, diphenhydramine hydrochloride and pseudoephedrine hydrochloride is used for the symptomatic treatment of common cold. In this study, a derivative spectrophotometric method based on zero-crossing technique was proposed for simultaneous determination of acetaminophen, diphenhydramine hydrochloride and pseudoephedrine hydrochloride. Determination of these drugs was performed using the (1)D value of acetaminophen at 281.5 nm, (2)D value of diphenhydramine hydrochloride at 226.0 nm and (4)D value of pseudoephedrine hydrochloride at 218.0 nm. The analysis method was linear over the range of 5-50, 0.25-4, and 0.5-5 µg/mL for acetaminophen, diphenhydramine hydrochloride and pseudoephedrine hydrochloride, respectively. The within-day and between-day CV and error values for all three compounds were within an acceptable range (CV<2.2% and error<3%). The developed method was used for simultaneous determination of these drugs in pharmaceutical dosage forms and no interference from excipients was observed.

CD44-targeted docetaxel conjugate for cancer cells and cancer stem-like cells: a novel hyaluronic acid-based drug delivery system.

A CD44-targeted macromolecular conjugate of docetaxel was prepared via a pH-sensitive linkage to hyaluronic acid and was characterized using NMR, gel permeation chromatography, and differential scanning calorimetry. The conjugated species were further evaluated in terms of drug release, cytotoxicity, cellular uptake, cell cycle inhibition, and subacute toxicity in mice. Cellular microscopic studies revealed that CD44-expressing cells including MCF-7 cancer stem cells and MDA-MB-231 metastatic breast cancer cells had internalized the conjugates via a selective receptor-mediated mechanism, leading to cell cycle arrest in the G2/M phase. Hyaluronic acid-docetaxel conjugates showed specific toxicity only in CD44-expressing cells in vitro, along with a decreased risk of neutropenia and dose-dependent mortality in vivo. Hyaluronic acid-drug conjugates represent a promising and efficient platform for solubilization of sparingly soluble molecules as well as active and selective targeted delivery to cancer cells and cancer stem cells.

Validating a stability indicating HPLC method for kinetic study of cetirizine degradation in acidic and oxidative conditions.

A stability indicating High-Performance Liquid Chromatography (HPLC) method was validated and used to study the degradation of cetirizine dihydrochloride in acidic and oxidative conditions. The separation was carried out on a Symmetry C18 column and a mixture of 50 mM KH2PO4 and acetonitrile (60:40 v/v, pH = 3.5) was used as the mobile phase. The method was linear over the range of 1-20 µg/mL of cetirizine dihydrochloride (r(2) > 0.999) and the within-day and between-day precision values were less than 1.5%. The results showed that cetirizine dihydrochloride was unstable in 2 M HCl and 0.5% H2O2. The kinetics of the acidic degradation showed a pseudo-first-order reaction in the temperature range of 70-90°C. In addition, the kinetics of hydrogen peroxide mediated degradation was pseudo-first-order in the temperature range of 50-80°C.