Element Determination in Pharmaceuticals Using Direct Solid Analysis- Electrothermal Vaporization Inductively Coupled Plasma Optical Emission Spectrometry

A solid sampling electrothermal vaporization inductively coupled plasma optical emission spectrometry (ETV-ICP OES) method for determination of As, Cd, Cr, Cu, Mn, Mo, Ni, Pb, Pd, Pt, Rh, Ru and V in pharmaceuticals is proposed. Tricyclic pharmaceuticals were directly analyzed due to their difficult decomposition with acids. Pyrolysis and vaporization temperature, sample mass, and reaction gas (Freon) flow rate were evaluated. The effect of organic and inorganic compounds was evaluated for matrix matching. The limits of detection ranged from 0.04 µg g−1 (Cu) to 107 µg g−1 (As) and the relative standard deviation was lower than 10%. The investigated elements were not detected in the analyzed samples with the exception of Cr in cyclobenzaprine hydrochloride. Since there was no certified reference materials available for metals and metalloids in pharmaceuticals, the accuracy of the method was evaluated by an independent technique and by analyte recovery. Inductively coupled plasma mass spectrometry was employed for analyte determination after sample decomposition by microwave induced combustion. The agreement of the results found by both techniques was better than 87% and analyte recoveries ranged from 91 to 103%.

本研究提出了一种用于测定药物中砷（As）、镉（Cd）、铬（Cr）、铜（Cu）、锰（Mn）、钼（Mo）、镍（Ni）、铅（Pb）、钯（Pd）、铂（Pt）、铑（Rh）、钌（Ru）及钒（V）的固体取样-电热蒸发-电感耦合等离子体发射光谱法（electrothermal vaporization inductively coupled plasma optical emission spectrometry，缩写ETV-ICP OES）。鉴于三环类药物难以通过酸解法完成前处理，本研究采用直接进样分析策略。对热解与汽化温度、样品称样量以及反应气（氟利昂，Freon）的流速进行了优化考察；针对基质匹配需求，评估了有机与无机化合物对测定的干扰效应。方法的检出限范围为0.04 μg·g⁻¹（铜）至107 μg·g⁻¹（砷），相对标准偏差均低于10%。在所分析的全部药物样品中，仅盐酸环苯扎林样品中检出了铬元素，其余目标元素均未被检出。由于目前尚无针对药物中金属及类金属元素的标准参考物质，本研究通过独立对照分析技术与加标回收实验对方法的准确度进行了验证：采用微波诱导燃烧法完成样品前处理后，通过电感耦合等离子体质谱法（inductively coupled plasma mass spectrometry，缩写ICP-MS）对目标元素进行定量测定。两种分析方法所得结果的吻合度优于87%，目标元素的加标回收率介于91%至103%之间。