Membranes made from nonsolvent-thermally induced phase separation (N-TIPS) for decellularization of blood in dry plasma spot (DPS) applications

Abstract The dried blood spot (DBS) is widely used for collecting microvolume blood for examining free amino acid concentrations in the blood for patients with defects in amino acid metabolism. However, comparing to many clinical tests which are based on cell-free plasma, the DBS system collects whole blood, where the presence of red blood cells (RBCs) may influence the qualitative and quantitative data analyses. Thus, we report novel membranes for decellularization of blood in the dried plasma spot (DPS) system. The membrane was held tightly with an absorbent paper underneath for collecting the permeated cell-free plasma. By combining the thermally induced phase separation (TIPS) and non-solvent induced phase separation (NIPS), i.e., N-TIPS, we have developed flat-sheet PAN membranes not only able to remove almost 100% RBCs but also allow most plasma to permeate through them effectively. The optimized membrane also has almost no retention to a few targeted amino acids.