A localized chemical pulse generator for the development of a microfluidic cell-based biosensor.

Cell-based biosensor (CBB) has shown potential to provide a rapid and sensitive measurement means for monitoring specific biological substances. However, the detecting frequency and reusability remain a challenge for further application of CBB. In this paper, a microfluidic cell-based biosensor (μCBB) was developed, which consisted of a localized millisecond chemical pulse as sample introduction for pulsing individual cells without interfering with adjacent cells and single HeLa cells expressing endogenous P2Y receptors as the sensing elements. Gated injection of pinched flow was used to generate millisecond ATP pulses with predefined width. By integrating localized ATP pulse with predefined width, multiple sensing elements could be used to detect ATP pulses without impact on their functionality. Thus, the detecting frequency of the developed μCBB is multiplied by the number of available cells in comparison to that reported previously. We expect the developed method to be potentially useful to enhance the usability of CBB for biological and biomedical analysis. [ABSTRACT FROM AUTHOR]