INTRODUCTION
Microfluidic technology can accurately control the movement of tiny amounts of liquid in micrometer scale flow channels [1]. Due to its advantages of small sample volume, fast reaction speed, high detection sensitivity, low cost, and portability, microfluidic platform is widely used in biological detection [2], chemical analysis [3]. Microfluidic chip design and manufacturing has been a hot topic in the scientific research field and commercial market. At present, the common materials used to manufacture microfluidic devices mainly include Polymethyl methacrylate (PMMA), glass, silicon, Polydimethylsiloxane (PDMS) and so on [4]. Among them, PDMS has become the most commonly used raw material for microfluidic chips in conventional laboratories due to its excellent physical and chemical properties [5], [6].