[[alternative]]Development of a PDMS microreactor fabricated for synthesizing Au nanoparticles

[[abstract]]The making of nanoparticles is important of nano-technologies in present. Gold nanoparticles have been widely used in the fields of opto-electric and bio-inspecting technologies, because it’s size, optical properties, surface chemical properties, and nonpoisonous characteristics. Therefore, the related techniques for preparing gold nanoparticles are requested to high monodispersity and controllability of particle diameters recently. Compared with the traditional reactor, PDMS microreactor has advantages of high biocompatibility, easily controlled and observed, and batch production, which can significantly improve the drawbacks of poor average particle diameters and imprecise controlled, to reach the purposes of reactor controlled in accuracy and gold nanoparticles can be produced in batches. Therefore, the present work fabricated the microreactor by SIGA technology of MEMS. By the aid of the software CFD (computational fluidic dynamics) analysis in simulation, there was a better result of mixing when the range of microchannel flow rate is 150 to 370 ul/min. In the etching processes in silicon mold, using the technique of adding surfactant (Br + IPA) in anisotropic wet etching can improve the defect of using single additive. It lowered the etching undercut ratio to 0.563 and roughness to 23.48 nm, and get the good silicon mold successfully. Synthesizing the gold nanoparticles, the Pt microheater in the microreactor gave the voltage was 13 to 14 V could provide the heating temperature about 120 ℃, and synthesized the absorption wavelength was 545 nm successfully when injected rate of dual-syringe infusion pump was 8 ul/min.