Figure 2.

(a) Schematic layout of the NOA device manufacturing method using NOA 63. NOA microfluidic chips require a PDMS of the channels to makes a stamp, which is taken from the patterned wafer. A PDMS device is created using a 5:1 ratio of the main agent and the curing agent thus creating a harder PDMS mold [26,27,28]. The mold is treated by vaporizing trichloro (1H, 1H, 2H, 2H-perfluorooctyl) silane (PFOTS) in a vacuum [25]. This leaves a small film of PFOTS on the surface of the PDMS, which can then be used as its own mold to fabricate PDMS devices with correctly oriented channels from the original PDMS device. The PDMS stamp is then slowly placed down on top of the NOA. The NOA is precured using UV light of 365 nm wavelength and 40.25 mW/cm³ intensity. The PDMS is then peeled off and the remaining NOA becomes an inverse replica of the PDMS stamp. A glass cover slip with the appropriate inlet and outlet holes is placed on top of the precured NOA chip. The NOA chip is then fully cured for 20 min under UV light. (b) Schematic layout of the PDMS device manufacturing method using a PDMS device. The PDMS device is taken from the patterned wafer and plasma bonded to a glass cover slip.