Dual Ratiometric Fluorescence Sensors Based on Chiral Carbon Dots for the Sensitive and Specific Detection of Arginine

Arginine (Arg) is involved in tissue metabolism and regulates the immune function; thereby, achieving the detection of Arg is crucial for early diagnosis and treatment of diseases. Herein, dual ratiometric fluorescence sensors were prepared with the blue emission of levorotatory/dextrorotatory carbon dots (CDs) and the red emission of porphyrin (L/D-CDs-PP) for the sensitive and portable detection of Arg. Interestingly, L-CDs-PP and D-CDs-PP displayed not only the dual emission peaks at 493 and 650 nm but also different response modes to Arg; thus, they could serve as dual ratiometric fluorescence sensors to achieve the accurate and reliable detection of Arg, with the detection limit of 23.87 μM for L-CDs-PP and 2.39 μM for D-CDs-PP. Importantly, the solid-state sensors successfully achieved dual-mode visual and portable detection of Arg with the support of a smartphone platform. In addition, L-CDs-PP and D-CDs-PP exhibited excellent biocompatibility and cell imaging capabilities, and they could achieve the detection of Arg in cells and biological samples of urine and rat plasma. Therefore, the dual ratiometric fluorescence sensors exhibited broad application prospects in the fields of analytical sensing, biological imaging, and medical diagnosis.