Adhesive Density of 11-Mercaptoundecanoic Acid (MUA) and Turnip Yellow Mosaic Virus (TYMV) in Microfluidic Channels

Abstract

Recently, there has been an increasing interest to develop rapid, reliable and low-concentration detection methods of micro-organisms involved in bioterrorism, food poisoning, and clinical problems. How to detect virus at concentration below the threshold will be challenging with respect to specificity, selectivity, and sensitivity. Among all parameters, sensitivity is probably the most critical consideration. If the sensitivity is not satisfied for real-time detection, researchers need to duplicate numerous numbers of viruses. However, it will substantially increase processing times and experimental hazard. To increase the sensitivity of virus sensors, this paper discusses how to increase the density of linkers and viruses on sensor’s surface in the microfluidic channels. In the future, researcher could use emerging technology, such as PT-PCR, QCM, C-V and I-V measurements, etc, to detect viruses on sensor’s surface. Usually microorganisms, molecules, or viruses in the fluidic environment are at very low Reynolds numbers because of tiny diameters. At very low Reynolds numbers, viscous forces of molecules and viruses will dominate. Those micro- or nanoparticles will stop moving immediately when flows cease and drag forces disappear. Of course, molecules and viruses are still subject to Brownian motion and move randomly. In order to increase the adhesion density of micro- and nanoparticles on sensor’s surface, designs of the flow movements in microfluidic channel is proposed. Adhesion density of linker 11-mercaptoundecanoic acid (MUA) and turnip yellow mosaic virus (TYMV) with specific quantum dots were measured by confocal microscope. Results show that TYMV and MUA layers disperse randomly by dipping method. Infusion rate, flow rate, and transverse flow could affect the adhesion densities of recognition layers on sensors’ surface. Adhesion densities of MUA and TYMV can be reached 70∼80% by microfluidic method to contrast just 10% by dipping method.