Review on bonding strength testing methods for polymer-based microfluidics

Abstract

Bonding is the key step in the fabrication of microfluidic devices. In the conventional approaches for the fabrication of polymer-based microfluidics, the substrate and cover plate were fabricated and then bonded to enclose the micro channels. Various methods have been invented for bonding polymer-based microfluidics, e.g. adhesive bonding, solvent bonding, thermal fusion, etc., materials with the same or different materials were bonded. The bonding quality of the polymer-based microfluidics is critical during use, leakage or even detachment is not allowed. The bonding quality of polymer-based microfluidic devices has been evaluated in different ways, some of the typical methods include the tensile test, shear test, and burst opening test, and each method has its own strengths and weaknesses. The standard procedure for bonding strength test hasn’t been established yet. In this study, different evaluation methods for bonding quality were discussed and compared in detail, the application scenarios for each method are also discussed. An outlook for the future standardization trend of bonding test methods for microfluidic device is also provided in this study.