A Capillary Electrophoresis Chip for Rhodamine B and Inorganic Ion detection Utilizing Contactless Capacitance Detection

A microfluidic channel and a contactless capacitance detector were integrated on a glass chip by a semiconductor manufacturing process for separating and analyzing Rhodamine B and inorganic ion. The electrodes of the capacitance detector were formed successively by sputtering, electroless and electrodepositions. Samples containing fluorescent agent (Rhodamine B) and inorganic ions (K, Na, and Li) were injected and separated in the microfluidic channel by the electrical voltage and detected by contactless capacitance measurement proposed in this work. The results showed that all the measured capacitance signals were very sharp and the reproducibility was quite well.