Department of Chemistry, Lehigh University, Bethlehem, PA 18015, USA.
Anal Bioanal Chem. 2011 Jul;400(10):3655-64. doi: 10.1007/s00216-011-5051-y. Epub 2011 May 10.
Passive exposure to tobacco smoke causes a variety of illnesses ranging from allergic responses to cancer. Assessment of exposure to second-hand tobacco smoke (SHS), particularly among vulnerable populations enables intervention and prevention of future disease. A minimally invasive oral fluids-based onsite test to detect such exposure would create a valuable tool for researchers and clinicians. Here we describe the development of a test that uses an inexpensive reader that utilizes a CMOS image sensor to reliably quantify a reporter signal and determine nicotine exposure. The rapid lateral flow test consists of a nitrocellulose strip with a control line containing goat anti-rabbit IgG, used as an internal standard, and a test line containing BSA-cotinine conjugate. To run the test, diluted sample containing antibodies against cotinine, the major metabolite of nicotine, is mixed with protein A-gold nanoparticles and placed on the sample pad. As the sample runs up to the nitrocellulose pad, antibodies in the running buffer bind to available cotinine. If cotinine is absent, the antibodies will bind to the BSA-cotinine derivative immobilized on the test line, resulting in an intense purple-red band. The concentration of cotinine equivalents in the sample can be estimated from interpretation of the test line. In this article we describe the effect of different cotinine derivatives, oral fluid pretreatment, and application and running buffers on assay sensitivity. The test can reliably detect as little as 2 ng mL(-1) cotinine equivalents. The assay is sensitive, simple, rapid, inexpensive, and easily implementable in point-of-care facilities to detect second-hand smoke exposure.
被动吸烟会导致各种疾病，从过敏反应到癌症不等。评估二手烟（SHS）暴露情况，特别是在脆弱人群中，能够进行干预并预防未来的疾病。一种微创的基于口腔液的现场测试方法来检测这种暴露情况，将为研究人员和临床医生创造一个有价值的工具。在这里，我们描述了一种测试的开发，该测试使用一种廉价的读取器，该读取器利用 CMOS 图像传感器可靠地量化报告信号并确定尼古丁暴露情况。快速横向流动测试由带有控制线的硝酸纤维素条组成，控制线包含山羊抗兔 IgG，用作内部标准，以及带有 BSA-可替宁结合物的测试线。要进行测试，将含有针对可替宁（尼古丁的主要代谢物）的抗体的稀释样品与蛋白 A-金纳米颗粒混合并放在样品垫上。当样品向上运行到硝酸纤维素垫时，运行缓冲液中的抗体与可用的可替宁结合。如果不存在可替宁，抗体将与固定在测试线上的 BSA-可替宁衍生物结合，导致强烈的紫红色带。可以通过解释测试线来估计样品中可替宁当量的浓度。在本文中，我们描述了不同可替宁衍生物、口腔液预处理以及应用和运行缓冲液对测定灵敏度的影响。该测试可以可靠地检测低至 2ngmL(-1)的可替宁当量。该测定方法灵敏、简单、快速、廉价，并且易于在现场护理点设施中实施，以检测二手烟暴露情况。
