Simultaneous Determination of Ropivacaine, Bupivacaine and Dexamethasone in Biodegradable PLGA Microspheres by High Performance Liquid Chromatography

Abstract

A simple and rapid high-performance liquid chromatography method coupled with UV detector was developed and validated for the simultaneous determination of ropivacaine, bupivacaine and dexamethasone in biodegradable poly (lactic-co-glycolic acid) (PLGA) microspheres within 11 min. Chromatographic separation was performed on a XDB-C 18 column using a mobile phase comprised of acetonitrile-NaH 2 PO 4 buŠer (pH 3.5, 30 mM) (30：70, v/v) with a ‰ow rate gradient program. The method was in good linearity (r＞0.999) over the range of 0.025 40.0 mg/ml for ropivacaine and bupivacaine, and 0.05 40 mg/ml for dexamethasone. The method was proved to be precise with intra-and inter-day precision less than 3.0％ and 6.0％ for all drugs and accurate with intra-and inter-day accuracy between  8.0％ to 4.5％ and between  5.0％ to 5.5％ for all drugs. The assay was rapid, simple and easy to apply. Therefore, it was very suitable for routine determination and quality control of ropivacaine, bupivacaine and dexamethasone in PLGA microspheres.

Polymeric and Solid Lipid Nanoparticles for Sustained Release of Carbendazim and Tebuconazole in Agricultural Applications

“…The nanocapsules (NCs) were prepared using the oil-in-water emulsion/solvent evaporation method described by Zhou et al . 50 . 10 mg of each fungicide (carbendazim and tebuconazole) were dissolved in 10 mL of acetone containing 200 mg of Myritol, and the resulting solution was added to 20 mL of chloroform containing 400 mg of polymer.…”

Promising potential of articaine-loaded poly(epsilon-caprolactone) nanocapules for intraoral topical anesthesia

“…Nanocapsule formulations were prepared by the oil-in-water emulsion/solvent evaporation method [23] based on the composition determined earlier [17]. Briefly, two solutions, one containing 400 mg of poly(ε-caprolactone) (PCL, Sigma-Aldrich, St. Louis, MO, USA) and 200 mg of Myritol 1 318 (donated by Chemspecs Comercio e Representaçoes Ltda., São Paulo, Brazil) in 20 mL of chloroform (Labsynth, Diadema, São Paulo, Brazil), and another with 200 mg articaine base dissolved in 10 mL of acetone (Labsynth, Diadema, São Paulo, Brazil), were mixed and sonicated for 1 min at 100 W. This pre-emulsion was added to 50 mL of aqueous solution containing 150 mg of polyvinyl alcohol surfactant (PVA, Sigma-Aldrich, St. Louis, MO, USA), with sonication for 8 min to form the emulsion.…”

Validation of an HPLC Method Devised for the Quantitative Determination of Ropivacaine in Drug-Delivery Systems

“…The mobile phase consisted of a mixture of acetonitrile and phosphate buffer (1 M NaHPO 4 2and 0.5 M NaH 2 PO 4 -, pH 8.0), 60: 40 v:v. The mobile phase was filtered through a 0.45μm Millipore ® membranes; flow rate was set to 1.2 mL/min, and oven temperature to 30 °C. The monitoring wavelength was 240 nm and the injection volume was 10 μL, according to Jönsson and coworkers [15] and USP 41 [18] .…”

“…HPLC is the method-of-choice for quantification of drugs in different fluids due to its sensitivity, reproducibility and specificity. Reports on the literature describe precise methods for the quantification, using HPLC, of local anesthetics in serum [11][12][13] , urine [14] and PLGA microspheres [15] . When a new method is developed it is important to validate it, to confirm it is suitable for the intended purposes.…”