1.A sensitive liquid chromatography-electrospray ionization-mass spectrometry method for the simultaneous determination of pentoxyverine citrate and guaifenesin in human plasma---application to pharmacokinetic and bioequivalence studies.
Wen J1, Zhang H, Xia C, Hu X, Xu W, Cheng X, Gao J, Xiong Y. Biomed Chromatogr. 2010 Apr;24(4):351-7. doi: 10.1002/bmc.1298.
A sensitive and specific liquid chromatography-electrospray ionization-mass spectrometry method for the identification and quantification of pentoxyverine citrate and guaifenesin in human plasma has been developed. After extraction from plasma samples by ethyl acetate, the internal standard and analytes were separated by high-performance liquid chromatographic on a Shim-pack VP-ODS C(18) column (150 x 2.0 mm) using a mobile phase consisting of A (methanol) and B (0.4% glacial acetic acid and 4 mmol/L ammonium acetate) (A:B, 43 : 57). Analysis was performed on a Shimadzu LC/MS-2010A in selected ion monitoring mode with a positive electrospray ionization interface. The method was linear in the concentration range of 1.0-640.0 ng/mL for pentoxyverine citrate and 0.025-6.4 microg/mL for guaifenesin. The inter- and intra- precision were all within 12% and accuracy ranged from 85 to 115%.The lower limits of quantification were 1.0 ng/mL for pentoxyverine citrate and 25.
2.Flow injection chemiluminescence method for the determination of pentoxyverine citrate based on NCS-dichlorofluorescein post-chemiluminescence reaction.
Zhang H1, Nie F, Lu J. Spectrochim Acta A Mol Biomol Spectrosc. 2009 May;72(4):858-62. doi: 10.1016/j.saa.2008.12.015. Epub 2008 Dec 24.
A post-chemiluminescence (PCL) phenomenon was observed when pentoxyverine citrate solution was injected into the reaction mixture after the finish of chemiluminescence (CL) reaction of N-chlorosuccinimide (NCS) and alkaline dichlorofluorescein. The possible reaction mechanism was proposed based on the studies of the CL kinetic characteristics, the CL spectra and the fluorescence spectra of some related substances. Based on the PCL reaction, a rapid and sensitive method for the determination of pentoxyverine citrate was established. The linear response range of this method was from 6.0x10(-9) to 1.0x10(-6)gmL(-1) with a linear correlation coefficient of 0.9998. The relative standard deviation for 2.0x10(-8)gmL(-1) pentoxyverine citrate was 2.1% (n=11). The detection limit was 9x10(-10)gmL(-1). This method has been applied to the determination of pentoxyverine citrate in human plasma and pharmaceutical samples with the satisfactory results.
3.Simultaneous determination of potassium guaiacolsulfonate, guaifenesin, diphenhydramine HCl and carbetapentane citrate in syrups by using HPLC-DAD coupled with partial least squares multivariate calibration.
Dönmez OA1, Aşçi B, Bozdoğan A, Sungur S. Talanta. 2011 Feb 15;83(5):1601-5. doi: 10.1016/j.talanta.2010.11.054. Epub 2010 Nov 30.
A simple and rapid analytical procedure was proposed for the determination of chromatographic peaks by means of partial least squares multivariate calibration (PLS) of high-performance liquid chromatography with diode array detection (HPLC-DAD). The method is exemplified with analysis of quaternary mixtures of potassium guaiacolsulfonate (PG), guaifenesin (GU), diphenhydramine HCI (DP) and carbetapentane citrate (CP) in syrup preparations. In this method, the area does not need to be directly measured and predictions are more accurate. Though the chromatographic and spectral peaks of the analytes were heavily overlapped and interferents coeluted with the compounds studied, good recoveries of analytes could be obtained with HPLC-DAD coupled with PLS calibration. This method was tested by analyzing the synthetic mixture of PG, GU, DP and CP. As a comparison method, a classsical HPLC method was used. The proposed methods were applied to syrups samples containing four drugs and the obtained results were statistically compared with each other.
4.[Bioequivalence evaluation of orally disintegrating tablet of pentoxyverine citrate].
Lin MQ1, Cai Y, Zhang W, Wu XQ, Rao JJ, Liu SW. Nan Fang Yi Ke Da Xue Xue Bao. 2010 Jul;30(7):1621-3.
OBJECTIVE: To evaluate the bioequivalence of orally disintegrating tablets of pentoxyverine citrate (tested preparation) in healthy male volunteers.