Mechanical analysis of oriented cell movement by nanostructure-based biosensors

Abstract

Due to the numerous diseases caused by apoptosis, the existing methods for detecting early apoptosis are not effective. To explore the effect of nanostructured biosensors on the directional movement of cells, silica@quantum dot-concanavalin A (SiO2@QDs-ConA) nanoprobes were prepared, and cholesterol amperometric biosensors based on carbon nanotubes were constructed by using the layer-by-layer assembly method. The results showed that in the presence of apoptotic cells, a sharp anodic stripping voltammetric signal was obtained, with a peak potential of about −0.7 V, corresponding to the oxidation peak of the cadmium (Cd2+) ion of the combined quantum dot nanoprobe. The signal of apoptotic cells was 3.9 and 15.0 times higher than those of normal cells and no cells, respectively, indicating the detection of apoptotic cells by electrochemical cell sensors in the early stage. Eight hours before the action of the apoptosis-inducing reagent, part of HL-60 cells underwent apoptosis. Sixteen hours after the action of the reagent, the apoptosis of HL-60 cells was obvious, the action time of the apoptosis-inducing reagent increased, the peak current of cadmium ion enrichment and dissolution increased rapidly and the HL-60 cells had obviously undergone apoptosis, indicating that most of the cells had obviously undergone apoptosis at this time, indicating that use of the constructed sensor is feasible for the early detection of apoptotic cells.