An impedimetric bioaffinity sensing chip integrated with the long-range DC-biased AC electrokinetic centripetal vortex produced in a high conductivity solution.
Ming-Jie LinYen-Fu LiuChing-Chou WuPublished in: Biomicrofluidics (2018)
Immunoreaction of specific antibodies to antigens is widely used in numerous immunoanalysis applications. However, diffusion-dominated transport in stationary solutions limits the rate and binding density of immunoreaction. This research describes the construction of chip-type concentric multi-double ring electrodes and single central disk electrode. A +1 V-biased 6 Vpp voltage was applied to the multi-double ring electrodes to induce a long-range DC-biased AC electrokinetic flow (ACEKF). The immunoreaction was quantified by electrochemical impedance spectrum (EIS). Fluorescence-labeled secondary antibody (FLSA) and protein A were exemplified as an immunoreacting model to demonstrate the effect of ACEKF on immunoreaction efficiency. The results showed that FLSA binding can reach a plateau in 8 min with the DC-biased ACEKF vortex, and the increment of electron transfer resistance is 2.26 times larger than that obtained in the unstirred solution. The sensitivity of the calibration curves obtained by EIS detection with the aid of DC-biased ACEKF vortex is 1.51 times larger than that obtained in an unstirred solution. The label-free EIS-based sensing chip integrated with the long-range DC-biased ACEKF vortex promises to facilitate immunoreaction efficiency, which is beneficial for the development of a miniature and fast-detection in vitro diagnostic device.
Keyphrases
- label free
- dendritic cells
- high throughput
- solid state
- circulating tumor cells
- electron transfer
- carbon nanotubes
- high resolution
- gold nanoparticles
- magnetic resonance imaging
- real time pcr
- single cell
- computed tomography
- loop mediated isothermal amplification
- small molecule
- single molecule
- liquid chromatography
- quantum dots
- molecularly imprinted
- simultaneous determination
- positron emission tomography
- pet ct