High Throughput Digital Droplet ELISA for Ultrasensitive Multiplexed Diagnostics

摘要： 数字分析-通过执行以下操作来进行超灵敏分子测量 数以百万计的皮升水滴的平行实验--最近引起了很大的热情 由于它们对RNA、DNA和蛋白质的单分子分辨率，以及它们对 反应条件。这些检测在治疗临终关怀疾病方面具有巨大的潜力。 诊断，但目前主要限于实验室环境，因为繁琐 生成、控制和测量数千万个独立的 水滴。为了克服这一挑战，我们提出了一种混合微电子/微流控芯片来 “解锁”基于液滴的临床使用的分析方法。我们的微滴兆卡探测器(µMD)可以 每秒产生和检测数百万个液滴的荧光(比 现有的数字方法)，同时实现比传统方法高1000倍的灵敏度 只使用传统的手机摄像头。我们方法的关键创新是 从电信行业借来的，其中我们用一种 伪随机序列，使单个液滴能够被解析，否则将 由于数码相机的帧速率有限而导致重叠。为了展示我们的力量 方法，我们把注意力集中在胰腺癌的诊断上。

Abstract: Digital assays — in which ultra-sensitive molecular measurements are made by performing millions of parallel experiments in picoliter droplets — have generated much recent enthusiasm due to their single molecule resolution of RNA, DNA, and proteins, and their robustness to reaction conditions. These assays have enormous untapped potential for point of care disease diagnostics, but are currently mainly confined to laboratory settings due to the cumbersome instrumentation necessary to generate, control, and measure tens of millions of independent droplets. To overcome this challenge, we propose a hybrid microelectronic / microfluidic chip to `unlock' droplet-based assays for clinical use. Our microdroplet megascale detector (µMD) can generate and detect the fluorescence of millions of droplets per second (1000× faster than existing digital approaches), while achieving a 1000x greater sensitivity than conventional ELISA, using only a conventional cell phone camera. The key innovation of our approach is borrowed from the telecommunications industry, wherein we modulate the excitation light with a pseudorandom sequence that enables individual droplets to be resolved that would otherwise overlap due to the limited frame rate of digital cameras. To demonstrate the power of our approach, we focus our attention on the diagnosis of pancreatic cancer.