A Simple, Easy to Fabricate Miniaturized Microfluidic Gradient Generator for Drug Testing Devices

To date, although microfabrication technologies for fabricating a microfluidic device are advanced, they are still time-consuming and laborious. Hence, we demonstrate the fabrication of microfluidic devices with a fast and easy maskless Ultraviolet (UV) projection method based on a stereolithography process in less than 5 mins. The flow model analysis by COMSOL gives the design concept of the gradient demonstrated. The fabricated chip is a miniaturized 25×25 mm2 gradient chip that produces gradient by maintaining equal width and length of each channel throughout the device. The design of the gradient is dependent on diffusion of molecules and hence is well suited for low flow rate applications such as drug delivery or cell related studies. The biocompatibility of the resins in their native form and with surface modification was evaluated by injecting cell culture medium to culture Human cervical cell line (HeLa) cells. Drug (Doxorubicin) screening was demonstrated by the viability of HeLa cells using Cell Counting Kit-8 (CCK-8) calorimetric assay. The miniaturized size of the chip aids these gradient generators to find applications in drug testing Lab-on-chip/Micro Total analysis systems (μTAS) and organ-on-chip devices.