CsPbCl3 perovskite quantum dots/TiO2 inverse opal photonic crystals for efficient photoelectrochemical detection of alpha fetoprotein

Abstract

All-inorganic perovskite quantum dots (PQDs) have caused extensive research interest because of their excellent optical and electrical properties. However, their water-instability limits their biological applications, and the researches of photoelectrochemical (PEC) biological detection based on CsPbCl3 PQDs are relatively rarely. In this report, the PEC biosensor based on CsPbCl3 QDs modified macroporous TiO2 inverse opal photonic crystals (IOPCs) is designed for alpha fetoprotein (AFP) detection. Firstly, the water stability of PQDs immobilized on IOPCs is remarkably enhanced. In addition, the large specific surface area of TiO2 IOPCs improves the fixed amount of AFP and decreases the electron transmission distance between PQDs and FTO substrate. Ultimately, the PEC biosensor based on TiO2 IOPCs/CsPbCl3 shows excellent detection performance with a low detection limit of 30 pg ml−1 and a good linear range from 0.08 ng ml−1 to 980 ng ml−1 for AFP detection in phosphate buffer saline solutions. This detection system has very extensive application prospect for AFP detection in clinical analysis and biological fields.