“…Due to its favorable features, ATPS is popularly used in industrial downstream processes to separate (figure 1(b)) and recover biological products in large quantities. Favorable features [1,2] of ATPS include: (i) lower interfacial tension between two similar phases, thus allowing easy mass transfer across this interface, (ii) formation of emulsion under a perturbation, which provides large interface area for mass transfer, (iii) a gentle aqueous environment suitable for live biological samples, and (iv) an ability to tailor ATPS for a particular aqueous two-phase extraction (ATPE) using affinity ligands [3]. Several successful applications of ATPS at microscale were reported, including rapid cell extraction [2,4], cell separation [1], rapid extraction and purification of protein [5,6], rapid tissue construction [7], enzyme analysis [8], precise cell delivery [9], and separation of target proteins [10].…”