Chapman Robert, Lin Yiyang, Burnapp Mark, Bentham Andrew, Hillier David, Zabron Abigail, Khan Shahid, Tyreman Matthew, Stevens Molly M
Department of Materials, Department of Bioengineering and Institute for Biomedical Engineering, Imperial College London, London SW7 2AZ, UK.
Mologic Ltd, Bedford Technology Park, Thurleigh, Bedfordshire, MK44 2YP, UK.
ACS Nano. 2015 Mar 24;9(3):2565-2573. doi: 10.1021/nn5057595. Epub 2015 Mar 10.
A rapid and highly sensitive point-of-care (PoC) lateral flow assay for phospholipase A2 (PLA2) is demonstrated in serum through the enzyme-triggered release of a new class of biotinylated multiarmed polymers from a liposome substrate. Signal from the enzyme activity is generated by the adhesion of polystreptavidin-coated gold nanoparticle networks to the lateral flow device, which leads to the appearance of a red test line due to the localized surface plasmon resonance effect of the gold. The use of a liposome as the enzyme substrate and multivalent linkers to link the nanoparticles leads to amplification of the signal, as the cleavage of a small amount of lipids is able to release a large amount of polymer linker and adhesion of an even larger amount of gold nanoparticles. By optimizing the molecular weight and multivalency of these biotinylated polymer linkers, the sensitivity of the device can be tuned to enable naked-eye detection of 1 nM human PLA2 in serum within 10 min. This high sensitivity enabled the correct diagnosis of pancreatitis in diseased clinical samples against a set of healthy controls using PLA2 activity in a point-of-care device for the first time.
通过从脂质体底物中酶触发释放一类新型生物素化多臂聚合物，在血清中展示了一种用于磷脂酶A2（PLA2）的快速且高度灵敏的即时检测（PoC）侧向流动分析方法。酶活性信号是由聚链霉亲和素包被的金纳米颗粒网络粘附到侧向流动装置上产生的，由于金的局域表面等离子体共振效应，这导致出现红色检测线。使用脂质体作为酶底物和多价连接子来连接纳米颗粒会导致信号放大，因为少量脂质的裂解能够释放大量聚合物连接子，并使更多量的金纳米颗粒粘附。通过优化这些生物素化聚合物连接子的分子量和多价性，可以调节该装置的灵敏度，从而能够在10分钟内对血清中1 nM的人PLA2进行肉眼检测。这种高灵敏度首次使得在即时检测装置中利用PLA2活性，针对一组健康对照对患病临床样本中的胰腺炎进行正确诊断成为可能。
