A paper-based lateral flow device for the detection of IalphaIP via ELISA

This study focuses on the development of a new paper-based microfluidic device for the detection of IalphaIP via ELISA. Recent studies proved that the concentration of IalphaIP is related to the mortality rate of patients who suffer from sepsis. The developed device is able to determine the concentration of IalphaIP in a buffer solution where a low concentration is an indicator for sepsis. Using a microfluidic valve, the reagents needed to perform the ELISA can be loaded sequentially. The microfluidic device consists of paper on which the channel geometry is printed with wax ink. Different layers of the device are stacked together with double sided tape where paper is biodegradable. After applying the reagents, the device produces the results autonomously in form of a colored dot. The intensity of the dot is linked to the concentration of the target analyte IalphaIP. Two methods to distinguish the concentration of IalphaIP were conducted to decide which method is more appropriate for this experiment. After optimizing the reagents with regards to reproducibility, optimal signal to noise ratio and sensitivity a standard curve is produced that links the intensity of a color dot to a concentration of IalphaIP. Compared to other methods like a blood test which needs 48 hours to deliver a result or microtiter-plates which need large fluid volumes, the microfluidic paper device is able to obtain a result within minutes as well as it uses smaller fluid volumes.