Versatile Biosensing Toolkit Using an Electronic Particle Counter

Abstract

Development of a versatile biosensing toolkit is in urgent need for rapid and multiplexed detection applications. In this work, an electronic particle counter-implemented versatile biosensing toolkit has been developed for detecting a range of targets with high sensitivity, broad detection range, multiplexibility, simple operation, and low cost. The electrical resistance-based particle counter conventionally measuring the number of microspheres (1–100 μm) can quantify analytes. The versatility of this approach is verified by assaying small molecules, protein biomarkers, pathogen bacteria, and tumor cells using three strategies: (1) antigen–antibody interaction, (2) DNA hybridization, and (3) polypeptide recognition. More importantly, this biosensing toolkit allows the simultaneous detection of multiple targets with a broad detection range from pg mL–1 to μg mL–1, showing great potential as a powerful technique for food safety testing and biomedical diagnosis.

Low-Cost and Convenient Microchannel Resistance Biosensing Platform by Directly Translating Biorecognition into a Current Signal

“…The two probes can specifically hybridize with the unique capture region LLO genes of L. monocytogenes DNA, with a sequence of CCT AAC ATA TCC AGG TGC TCT CGT GAA AGC GAA TTC GGA ATT AGT AGA AAA TCA ACC CGA TGT TCT TCC TGT CAA ACG TG. 26 The mechanism of L. monocytogenes detection is shown in Figure 4A. For positive samples, the unique region of L. monocytogenes DNA will hybridize with the capture probe on the MBs and the detection probe on the PS microspheres, resulting in a quantitative decrease in the unreacted PS microspheres.…”

“…The two probes can specifically hybridize with the unique capture region LLO genes of L. monocytogenes DNA, with a sequence of CCT AAC ATA TCC AGG TGC TCT CGT GAA AGC GAA TTC GGA ATT AGT AGA AAA TCA ACC CGA TGT TCT TCC TGT CAA ACG TG . The mechanism of L.…”

“…The modification of MB-COOH and PS-COOH with biorecognition molecules is according to the strategy described in our previous study. , Taking the procedure of modifying MB-COOH with the capture antibody of PCT as an example, the details are illustrated as follows. First, the carboxyl groups on the MBs were activated by EDC.…”

Click Chemistry-Mediated Particle Counting Sensing via Cu(II)-Polyglutamic Acid Coordination Chemistry and Enzymatic Reaction

“…The measurement procedure was carried out according to our previous work as follows: the signal value of normal saline was measured as background, 100 μL of the collected solution was added to measure the particle number. Particles with a size distribution of 2.6–3.7 μm are counted as 3 μm microspheres, whose average size is 3 μm . LOD was calculated based on the calibration curve with 3 S / M , where S is the value of the standard deviation of blank samples and M is the slope of the standard curve at a low-concentration range.…”

“…Compared with LFIA, ELISA employs enzymes to amplify detection signals, but its sensitivity is still incapable of detection of hazardous factors at trace levels. In our previous work, an electronic particle counter-implemented versatile biosensing toolkit was developed for detecting a range of targets including protein biomarkers, small molecules, pathogenic bacteria, and even cells . In this sensing strategy, magnetic beads (MBs) coupled with antibodies or molecular probes were employed to capture the target of interest, and polystyrene (PS) microspheres coupled with recognition elements were used as signal probes to detect the target.…”