Assessment of the Performance of Solid Phase Extraction Based on Pipette Tip Employing a Hybrid Molecularly Imprinted Polymer as an Adsorbent for Enantioselective Determination of Albendazole Sulfoxide.

Herein, an organic-inorganic hybrid molecularly imprinted polymer (MIP) was successfully synthesized with albendazole sulfoxide (ABZSO) as a template and 3-(trimethoxysilyl)propyl methacrylate, a bifunctional group compound, as a single cross-linking agent. In this study, a simple method using HPLC-DAD was developed for the determination of ABZSO enantiomers in human urine using pipette tip-based molecularly imprinted polymer solid phase extraction (PT-MIP-SPE). Enantioseparation with satisfactory retention times (5.17 and 7.09 min), acceptable theoretical plates (N = 4,535 and 5,091) and strong resolution (Rs = 5.45) was performed with an Agilent® Eclipse Plus C18 (100 mm × 4.6 mm, 3.5 µm) coupled with a Chiralpak® IA column (100 mm × 4.6 mm, 3 µm), a mixture with ethanol:water (50:50, v/v) as the mobile phase, temperature at 40°C, flow rate at 0.9 mL min-1 and λ = 230 nm. Thereafter, certain parameters affecting the PT-MIP-SPE were investigated in detail and the better conditions were: 300 µL of water as washing solvent, 500 µL of ethanol:acetic acid (9:1, v/v) as eluting solvent, 20 mg of MIP, 500 µL of human urine at pH 9 and no addition of NaCl. Recoveries/relative standard deviation (RSD%) for (R)-(+)-ABZSO and (S)-(-)-ABZSO were 78.2 ± 0.2% and 69.7 ± 1.7%, respectively.

Evaluation of physicochemical properties as supporting information on quality control of raw materials and veterinary pharmaceutical formulations.

This study aimed to show that the physicochemical proprieties obtained by Fourier transform infrared spectroscopy (FTIR), thermogravimetry (TG), and scanning electronic microscopy (SEM) can be useful tools for evaluating the quality of active pharmaceutical ingredients (APIs) and pharmaceutical products. In addition, a simple, sensitive, and efficient method employing HPLC-DAD was developed for simultaneous determination of lidocaine (LID), ciprofloxacin (CFX) and enrofloxacin (EFX) in raw materials and in veterinary pharmaceutical formulations. Compounds were separated using a Gemini C18 (250 mm × 4.6 mm, 5 µm) Phenomenex® column, at a temperature of 25 °C, with a mobile phase containing 10 mM of phosphoric acid (pH 3.29): acetonitrile (85.7:14.3, v/v) and a flow rate of 1.5 mL/min. Physicochemical characterization by TG, FTIR, and SEM of raw materials of LID, CFX, and EFX provided information useful for the evaluation, differentiation, and qualification of raw materials. Finally, the HPLC method was proved to be useful for evaluation of raw material and finished products, besides satisfying the need for an analytical method that allows simultaneous determination of EFX, CFX, and LID, which can also be extended to other matrices and applications.