A low temperature bonding of quartz microfluidic chip for serum lipoproteins analysis

摘要

A low-temperature bonding method for microfab-rication of quartz microfluidic chips has been developed. The bonding process involved two steps: pre-bonding and post-annealing at low temperature. The bonding quality was evaluated by measuring the shear force at bonding interface and the electrical properties of the chips. Shear force of 5.66 MPa (566 N/cm~2) was obtained in a bonded chip after a post-annealing at 200℃ for 6 h. We owe the strong bonding strength to the formation of Si—O—Si bonds at the bonding interface during the post-annealing stage. The bonding procedures were not sensitive to surrounding and could be performed in a routine laboratory without clean room conditions. The performance of the fabricated microfluidic chips was tested by capillary zone electrophoresis (CZE) of serum lipoproteins with laser-induced fluorescence (LIF). The low-density (LDL) and high-density (HDL) lipoproteins in the serum was separated completely by using tricine buffer with methylglucamine.