pH-responsive zwitterionic carbon dots for detection of rituximab antibody

Zwitterionic carbon dots (CDs) have received much attention as a result of good photostability, high biocompatibility, and high quantum yield. In this study, novel zwitterionic CDs were synthesized using a simple hydrothermal method of citric acid (CA) and l-histidine as carbon and nitrogen precursors, respectively. Prepared zwitterionic CDs have an average particle size of 4 nm diameter and showed green fluorescence with a peak at 530 nm when excited at 470 nm; quantum efficiency was 39.34% using rhodamine 6G as a baseline. The fluorescence intensity of zwitterionic CDs was quenched by rituximab in the range 0-400 mu mol L-1, with a limit of detection of 27 mu mol L-1. In addition, the synthesized zwitterionic CDs had low toxicity, good stability, and high selectivity and sensitivity sensing for rituximab, therefore zwitterionic CDs are a promising candidate for practical applications.

Automated summary

Novel zwitterionic carbon dots with good fluorescence properties were successfully synthesized in this study, showing high selectivity and sensitivity for detecting rituximab, along with low toxicity and good stability.