Carbon Dots-Based Surface Plasmon Resonance Manganese Ion Fiber Sensor for Multi-Use Scenarios

Heavy metal ions have drawn enough attention due to their harm to both humans and environments, and there has been an urgent need for stable and quick detection of them. Besides, the manganese ion is one of the most abundant ions in urban water systems, which needs to be monitored carefully. Hereby, a carbon dots (CDs) (the microwave method) based surface plasmon resonance (SPR) Mn²⁺ sensor has been proposed and discussed, which could achieve high detection sensitivity of 6.383 nm/lg(ppb) in the range of 0 ppb–200 ppb on manganese ions, with the detection limit of 0.3462 ppb. The proposed sensor also possesses high stability upon time and temperature, and it also has great ion selectivity against 9 other ions. Practical usage scenarios have been tested on the human serum, tap water, lake water, and river water, which confirm that the proposed sensor holds great potential for both blood tests and environmental monitoring.