Analysis of Separation of Particles in a Suspension in a Microfluidic Channel

Abstract

Blood plasma provides critical details about human health conditions. Blood plasma separation has direct, obvious applications in human health monitoring, disease diagnostics, and theranostics. Separation of plasma from whole blood is a very primary step in the medical field for disease diagnostics and human health monitoring. Conventionally, plasma is separated from whole blood using a Centrifugation process which is although efficient but time-consuming, batch type process, and requires a large volume of blood. In present work, very efficient technique of separation of plasma from whole blood using microfluidic device has been discussed in details which possess advantages like efficient blood plasma separation, real-time monitoring and on sight sample testing. It requires a small volume of a blood sample to separate plasma from it. An in-house cost effective microfabrication method of microchannel mold using dry film photoresist has been developed which is a convenient alternative of conventional liquid photoresist based microfabrication techniques for fast-prototyping of microchannel molds. This method required limited investment for equipments and hence about 10 times cheaper than liquid photoresist based techniques. Microchannel device working on a principle of hydrodynamic separation of particles has been designed and fabricated to separate plasma from whole/diluted blood. Performance of a microchannel device as a function of dependent governing parameters such as resistance ratio of bifurcating daughter channels, inlet flow rate and feed blood hematocrit has been analyzed. This device works at an optimum flow rate of 0.8 ml/min and efficiently separates plasma from blood up to 38% Hematocrit. Performance analysis of the syringe pump and the peristaltic pump has been studied through the experiments and how a pulsatile nature of flow affects separation efficiency has been described. Based on the experimentation it is found that separation efficiency is higher in the case of a syringe pump as compared to a peristaltic pump. Hemolysis trend has also been observed for both the pumps.