Chemistry Department, Faculty of Science, Cairo University, Giza 12613, Egypt; Chemistry Department, College of Science, Jouf University, P. O. Box 72341, Sakaka, Al-Jouf, Saudi Arabia.
Chemistry Department, Faculty of Science, Cairo University, Giza 12613, Egypt.
Spectrochim Acta A Mol Biomol Spectrosc. 2019 Nov 5;222:117186. doi: 10.1016/j.saa.2019.117186. Epub 2019 May 28.
Pentoxyverine citrate (PEN-citrate) is an antitussive (cough suppressant) drug used for cough associated with illnesses like common cold. In this work, PEN-citrate is quantified by applying a simple, direct and accurate spectrophotometric method in pure form, pharmaceutical formulation (Cabella®, 2.13 mg/mL) and human serum samples. The formation of a stable yellow ion-pair with sulfonephthalein dyes; bromocresol green (BCG), bromophenol blue (BPB), bromothymol blue (BTB), bromocresol purple (BCP), bromochlorophenol blue (BChPB) and bromoxylenol blue (BXB), in three nonpolar solvents (chloroform, dichloromethane, acetonitrile) is used as the basis for this method. This is the first assay method reported for the quantification of PEN-citrate using the sulfonephthaleins as coloring agents. Diverse parameters were investigated in order to optimize the calibration curve conditions. The strategy was validated with respect to linearity range, precision, accuracy, specificity, robustness and limits of detection (LOD) and quantification (LOQ). In addition, solvents of different polarities were utilized to investigate the color reaction, light absorption and to allow for increasing the method sensitivity. Beer's law is obeyed over a wide concentration range (up to 42.05 μg/mL in case of BTB method). LOD and LOQ values reached 0.22 and 0.72 μg/mL, respectively, upon using BChPB. The relative standard deviation (%RSD) was ≤1.91% while correlation coefficient values (r) were ≥ 0.9974. High molar absorptivity values and low values of Sandell's sensitivity were obtained indicating that the proposed methods are highly sensitive. The validated methods were applied to the analysis of PEN-citrate in the dosage form and human serum samples where the drug was successfully resolved from the pharmaceutical additives and serum components with recoveries ≥98.98%.
枸橼酸喷托维林（PEN-citrate）是一种镇咳药（咳嗽抑制剂），用于治疗普通感冒等疾病引起的咳嗽。在这项工作中，通过应用简单、直接和准确的分光光度法，在纯品、药物制剂（Cabella®，2.13mg/mL）和人血清样本中定量了 PEN-citrate。该方法的基础是磺酸萘酚染料；溴甲酚绿（BCG）、溴酚蓝（BPB）、溴百里酚蓝（BTB）、溴甲酚紫（BCP）、溴氯酚蓝（BChPB）和溴甲酚绿（BXB）与亚砜萘酚染料在三种非极性溶剂（氯仿、二氯甲烷、乙腈）中形成稳定的黄色离子对。这是首次报道使用磺酸萘酚作为显色剂定量测定枸橼酸喷托维林的分析方法。为了优化校准曲线条件，研究了多种参数。该策略在线性范围、精密度、准确度、特异性、稳健性和检测限（LOD）和定量限（LOQ）方面进行了验证。此外，还使用了不同极性的溶剂来研究显色反应、光吸收，以提高方法的灵敏度。在 BTB 方法中，在较宽的浓度范围内（高达 42.05μg/mL）符合比尔定律。当使用 BChPB 时，LOD 和 LOQ 值分别达到 0.22 和 0.72μg/mL。相对标准偏差（%RSD）≤1.91%，相关系数（r）≥0.9974。高摩尔吸光值和低桑德尔灵敏度值表明所提出的方法具有高度的灵敏度。所建立的方法用于分析药物制剂和人血清样本中的 PEN-citrate，该药物成功地与药物添加剂和血清成分分离，回收率≥98.98%。
