Pinto Paula C A G, Saraiva M Lúcia M F S, Santos João L M, Lima José L F C
REQUIMTE/Physical-Chemistry Department, Faculty of Pharmacy, Porto University, Rua Aníbal Cunha 164, Porto, Portugal.
Talanta. 2006 Jan 15;68(3):857-62. doi: 10.1016/j.talanta.2005.06.008. Epub 2005 Jul 14.
A sequential injection analysis (SIA) methodology for the fluorimetric determination of aminocaproic acid in pharmaceutical formulations is proposed. The developed analytical procedure is based on the derivatisation reaction of the aminocaproic primary amine with o-phthalaldehyde (OPA) and N-acetylcysteine (NAC) and fluorimetric detection of the formed product (lambda(ex)=350 nm; lambda(em)=450 nm). The implementation of a SIA flow system allowed for the development of a simple, fast and versatile automated methodology, which exhibits evident advantages regarding the US Pharmacopoeia 24 (USP 24) reference procedure. By combining the SIA time-based sample insertion with a subsequent zone sampling approach, which permitted to select for detection of a well-defined sample zone, it was possible to implement an on-line dilution strategy that enabled the expansion of the analytical working range of the methodology, and thus its application in dissolution studies, without manifold re-configuration. Linear calibration plots were obtained for aminocaproic acid concentrations up to 6 x 10(-5)mol l(-1). The developed methodology exhibit a good precision, with a R.S.D.<2.0% (n=15) and the detection limit was 2.5 x 10(-7)mol l(-1). The obtained results complied with those furnished by the reference procedure with a relative deviation lower than 1.2%. No interference was found.
提出了一种用于荧光测定药物制剂中氨基己酸的顺序注射分析（SIA）方法。所开发的分析程序基于氨基己酸伯胺与邻苯二甲醛（OPA）和N-乙酰半胱氨酸（NAC）的衍生化反应，并对形成的产物进行荧光检测（激发波长λ(ex)=350 nm；发射波长λ(em)=450 nm）。SIA流动系统的应用使得开发一种简单、快速且通用的自动化方法成为可能，该方法相对于美国药典24（USP 24）参考程序具有明显优势。通过将基于时间的SIA进样与随后的区域进样方法相结合，该区域进样方法允许选择明确的样品区域进行检测，从而能够实施在线稀释策略，扩大了该方法的分析工作范围，进而使其可应用于溶出度研究，而无需对流路进行重新配置。氨基己酸浓度高达6×10⁻⁵ mol·L⁻¹时获得了线性校准曲线。所开发的方法具有良好的精密度，相对标准偏差R.S.D.<2.0%（n = 15），检测限为2.5×10⁻⁷ mol·L⁻¹。所得结果与参考程序提供的结果相符，相对偏差低于1.2%。未发现干扰。
