Institute of Hydrochemistry and Chair for Analytical Chemistry, Technische Universität München, Germany.
Anal Chim Acta. 2011 Mar 18;689(2):234-42. doi: 10.1016/j.aca.2011.01.030. Epub 2011 Feb 2.
Ochratoxin A (OTA) can contaminate foodstuffs in the ppb to ppm range and once formed, it is difficult to remove. Because of its toxicity and potential risks to human health, the need exists for rapid, efficient detection methods that comply with legal maximum residual limits. In this work we have synthesized an OTA conjugate functionalized with a water-soluble peptide for covalent immobilization on a glass biochip by means of contact spotting. The chip was used for OTA determination with an indirect competitive immunoassay format with flow-through reagent addition and chemiluminescence detection, carried out with the stand-alone automated Munich Chip Reader 3 (MCR 3) platform. A buffer model and real green coffee extracts were used for this purpose. At the present, covalent conjugate immobilization allowed for at least 20 assay-regeneration cycles of the biochip surface. The total analysis time for a single sample, including measurement and surface regeneration, was 12 min and the LOQ of OTA in green coffee extract was 0.3 μg L(-1) which corresponds to 7 μg kg(-1).
赭曲霉毒素 A（OTA）可以在 ppb 到 ppm 范围内污染食品，而且一旦形成，就很难去除。由于其毒性和对人类健康的潜在风险，因此需要快速、高效的检测方法，以符合法定的最大残留限量。在这项工作中，我们合成了一种与水溶性肽偶联的 OTA 共轭物，通过接触点样将其共价固定在玻璃生物芯片上。该芯片用于通过流动试剂添加和化学发光检测的间接竞争免疫测定格式进行 OTA 测定，使用独立的自动化慕尼黑芯片读取器 3（MCR 3）平台进行。为此目的，使用了缓冲模型和真正的绿咖啡豆提取物。目前，共价偶联物固定化至少允许生物芯片表面进行 20 次测定-再生循环。单个样品的总分析时间包括测量和表面再生，为 12 分钟，绿咖啡豆提取物中 OTA 的 LOQ 为 0.3 μg L（-1），相当于 7 μg kg（-1）。
