Plasma separation from blood: the 'lab-on-a-chip' approach.

Component analysis of blood is a key diagnostic step in the detection of diseases. The separation of plasma from blood cells is therefore critical for the accuracy of diagnostic tests because cellular fractions can create discrepancies in analysis. The conventional method for separating the cellular fraction from whole blood is by centrifugation, which requires a laboratory infrastructure. In the last decade, intensive research to scale down experimental processes has seen unprecedented advances in microfabrication and related techniques that have led to utilization of the micro-level phenomenon to accomplish a myriad of physicochemical separation processes. Salient features of these devices include small sample size, faster reaction times, precise control of reaction environments, and affordability. Various plasma-separation devices have also been designed based on microfluidic platforms. The challenges associated with these devices are manifold: particle clogging, necessity for sample preparation, flow-rate maintenance, low reproducibility, and optimization of output. Further, quality, reliability, and consistency remain a huge issue with micromedical devices. The present article reviews current developments in the field of plasma separation from blood implementing innovative microtechnologies to achieve high-throughput plasma separation.