Scholarlink

Abstract <p>Charge-transfer (<b>CT</b>) complexation offers a valuable strategy in pharmaceutical analysis for determining active pharmaceutical ingredients in both pure and formulated forms. In this study, tramadol hydrochloride (<b>TM</b>) acted as an electron donor and 2,4,6-trinitrophenol (picric acid, <b>PA</b>) as a π-acceptor, forming a stable 1 : 1 CT complex in acetonitrile. The reaction was optimized for spectrophotometric quantification, showing linearity over 30–180 μg/mL with high correlation coefficient. The method was validated according to the International Council for Harmonization guidelines, demonstrating satisfactory accuracy, precision, selectivity, and sensitivity. Application to commercial tramadol formulations confirmed its suitability for routine quality control. Complementary density functional theory (<b>DFT</b>) and time-dependent-DFT calculations provided molecular-level insight into the CT mechanism. Frontier molecular orbital analysis verified electron transfer from TM (highest occupied molecular orbital) to PA (lowest unoccupied molecular orbital), while molecular electrostatic potential mapping identified favorable donor-acceptor regions stabilizing the complex. Overall, the combined experimental-theoretical approach establishes a simple, rapid, and reliable spectrophotometric method for TM determination.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Density Functional Theory-Supported Studies of the Spectrophotometric Determination of Tramadol via Charge-Transfer Complexation with Picric Acid

  • 期刊论文

  • 发表日期：

    2026年2月1日

查看全文
  • Abanoub Mosaad Abdallah

摘要

Abstract

Charge-transfer (CT) complexation offers a valuable strategy in pharmaceutical analysis for determining active pharmaceutical ingredients in both pure and formulated forms. In this study, tramadol hydrochloride (TM) acted as an electron donor and 2,4,6-trinitrophenol (picric acid, PA) as a π-acceptor, forming a stable 1 : 1 CT complex in acetonitrile. The reaction was optimized for spectrophotometric quantification, showing linearity over 30–180 μg/mL with high correlation coefficient. The method was validated according to the International Council for Harmonization guidelines, demonstrating satisfactory accuracy, precision, selectivity, and sensitivity. Application to commercial tramadol formulations confirmed its suitability for routine quality control. Complementary density functional theory (DFT) and time-dependent-DFT calculations provided molecular-level insight into the CT mechanism. Frontier molecular orbital analysis verified electron transfer from TM (highest occupied molecular orbital) to PA (lowest unoccupied molecular orbital), while molecular electrostatic potential mapping identified favorable donor-acceptor regions stabilizing the complex. Overall, the combined experimental-theoretical approach establishes a simple, rapid, and reliable spectrophotometric method for TM determination.