A novel label-free bioengineered cell-based biosensor for salicin detection

Salicin is a bitter compound with important pharmaceutical values. The detection of salicin in pharmaceutical industry usually employs standard methods of analytical chemistry such as high performance liquid chromatography, which is not suitable for primary detection due to the complicated operation process and expensive systems. In this study, we explore the feasibility of using a label-free bioengineered cell-based biosensor to detect salicin. A human bitter taste receptor, T2R16, which could specifically respond to salicin, was expressed in HEK-293 cells as sensing elements of the biosensor. The structural and functional expression of T2R16 was validated by immunofluorescent staining and calcium imaging. The cell-impedance sensor was utilized as secondary transducer to detected cellular responses to salicin. The cell-impedance response of the bioengineered cells to salicin was investigated by analyzing the response intensity under various concentrations. The cell-impedance results revealed that this bioengineered cells could respond to salicin in a dose-dependent relationship. Finally, the performance of this bioengineered cell-based biosensor was evaluated. In cell-impedance measurement, non-transfected HEK-293 cells were not responsive to salicin, which proved the specificity of the biosensor. The detection of salicin at two unmeasured concentrations in standard response curve also proved this biosensor was sensitive in salicin detection. With the advantage of label-free measurement, this bioengineered may provide a promising and valuable approach for primary and quick detection of salicin. (C) 2016 Published by Elsevier B.V.