Out-of-plane valve for blood separation and metering: towards lab-in-a-tube applications for blood diagnostics

Abstract

Diagnostics plays a critical role in human health, while blood analysis is one of the most common clinical diagnoses. Biomedical engineers have been developing technologies that can robotically perform accurate and rapid blood analysis for field application. The simplified fabrication processes and low cost materials become the tendency of point-of-care (POC) devices for blood analysis. Recently, lab-in-a-tube technique comes up as a simple and robust method for POC measurements of multiple analytes. This paper proposed a tubing system with out-of-plane valves using tygon tubing assembled on a circular disc (CD) for blood separation. Pure plasma could be achieved within minutes after extracting blood from human body. The out-of-plane valve showed excellent capability in preventing backflow and reverse mixing due to diffusion. Therefore, the lab-in-a-tube platform has promising applications for the automation of POC analysis, especially important for the rural areas without enough medical resources.