原文献:A Multi-channel Handheld Automatic Spectrometer for Wide Range and On-site Detection of Okadaic Acid Based on Specific Aptamer Binding
文献链接:https://xueshu.baidu.com/usercenter/paper/show?paperid=11480ra07q2p0gr0sv210rm0hx440022&site=xueshu_se
作者:Chiyu Ma, Xianyou Sun, Liubing Kong, Xinyi Wang, Shuqi Zhou, Xinwei Wei,Dmitry Kirsanov, Andrey Legin, Hao Wanl, Ping Wang
相关产品:AuNPs
原文摘要:Okadaic acid (OA) is one of the marine toxin that is widely distributed and harmful to humanHowever, the current detection methods for OA have complex procedures, long detection time, andrely on large-scale laboratory equipment. In this work, a multi-channel handheld automaticspectrometer (MHAS) based on a spectral sensor was developed with the advantages of small sizesimple operation and low cost. It could achieve a rapid detection within 30 s and a wide spectradetection range of 470 - 780 nm with a broadband LED as the light source and a microplate containing8 wells as sample cell. Moreover, through the combination of gold nanoparticles (AuNPs) andaptamer-0A34, a high sensitive and rapid system for OA detection was established with a LOD of1 .80 ug/L and a wide detection range of20 - 10000 ug/L, which is comparable to a microplate readerCompared with other studies, the proposed MHAS realized the rapid on-site detection of OA with awider detection range, shorter detection time and higher portability. Therefore, MHAS is promising tobe a stable and efficient optical detection instrument for on-site detection in the fields of food safetydisease diagnosis and environmental.
冈田酸(OA)是一种海洋du素。然而,目前的OA检测方法程序复杂,检测时间长,依赖于大型实验室设备。开发了一种基于光谱传感器的多通道手持式自动光谱仪(MHAS),具有体积小、操作简单等优点。以宽带LED为光源,以含孔的微孔板为样品单元,可在30 s内实现快速检测,并实现470 - 780 nm的宽光谱检测范围。此外,通过金纳米颗粒(AuNPs)和适配体-oa34结合,建立了高灵敏度、快速的OA检测系统。该光谱仪检测原理过程和表征如下:
图:AuNPs
本研究建立的结合AuNPs和适配体-OA34的OA检测的光谱分析方法。首先,在样品溶液中加入OA。在样品溶液中没有OA,适配体处于自由状态,然后加入AuNPs。游离的适配体可以通过Au-N化学键在AuNPs表面被吸收,并保护AuNPs。在盐溶液中,由于表面电荷和空间位阻的变化,受适配体保护的AuNPs的稳定性会增加。此时,当氯化钠加入到混合的溶液中时,除了受适配体保护的氯化钠外,AuNPs将聚集。在存在OA的情况下,适配体将特异性结合,使混合溶液中的游离适配体减少,适配体保护的AuNPs也减少。当加入氯化钠时,AuNPs的聚集程度将会增加,溶液的颜色将会进一步从酒的红色变为蓝灰色。通过AuNPs的吸收峰与聚集的吸收峰的比值,可以进行定量测量,从而实现快速的检测。
如图A所示,AuNPs的直径约为15 nm,颗粒具有良好的分散性。当加入氯化钠时,受1 μM OA34保护的AuNPs仅发生轻微聚集(图B),而没有OA34保护的AuNPs发生严重聚集(图C),导致吸光度差异。当AuNPs不聚集的情况下,其吸光度曲线仅在520 nm处出现峰值,而在520 nm处的峰值减小,在690 nm处出现聚集峰,随着聚集程度的增加(图D)。这是因为AuNPs在受到影响时会聚合通过带正电荷的粒子,被粒子团吸收的光的波长由于粒子簇的粒子大小的变化而改变。因此,研究使用这两个波长(Ex(520/690))的吸光度率来量化AuNPs的聚集程度,从而反映了OA的浓度。
图:AuNPs的实验表征
结论:建立了一种基于金纳米颗粒的多通道手持式OA现场检测自动光谱仪。基于AuNPs和适配体的OA检测方法具有快速响应,较宽的检测范围(20μg/L~10 mg/L)和良好的检测下限。在MHAS的帮助下,在50 min内可以大大缩短光学检测时间,并且检测性能相当于酶标仪。通过与300酶标仪的比较评价,证明了MHAS在光学检测中的灵敏度和稳定性。此外,MHAS具有良好的抗干扰能力和较高的便携性。