Masayasu Suzuki, Toyohiro Ohshima, Shintaro Hane, Yasunori Iribe, and Tatsuya Tobita

Abstract:
Evaluating cell activity and functions in different-sized cell chambers requires multiscale sensing. We have been developing multiscale biosensing applied from 10 $mu $m to 1 mm. We measured mouse IgG in micro wells using a high-resolution two-dimensional surface plasmon resonance (SPR) imaging affinity sensor. This sensor uses high refractive optics, a 1X to 7X microscopic lens, and a cooled CCD camera. The micro-well array was prepared with a PDMS film on gold sensor film. Protein A immobilized on sensor film was used for IgG recognition. SPR sensitivity was dramatically decreased with 10 and 8.5 $mu $m microwells. To improve sensor sensitivity, we optimized the sensor's measurement angle and exposure time, enabling mouse IgG to be detected in wells of 1 mm, 30 $mu $m, and 10 $mu $m using the same 2D-SPR imaging sensor and measurement protocol. These results show the feasibility of multiscale biosensing use in antibody production in a micro well or a cell chamber.

Keywords: surface plasmon resonance, SPR imaging, cell chip, micro-array, IgG