Rapid and universal detection of ovalbumin based on N,O,P-co-doped carbon dots-fluorescence resonance energy transfer technology

Fluorescence resonance energy transfer (FRET), a near-field energy transfer from a fluorescent donor to a fluorescent acceptor within close proximity, has been widely used in biosensing. In this study, a rapid and universal sensor for the detection of ovalbumin (OVA) using nitrogen, oxygen, phosphoric co-doped CDs( NOP-CDs) and graphene oxide (GO) was established based on the FRET technology. First, novel NOP-CDs peak at 443 nm were synthesized by a one-pot hydrothermal method using egg powder and phosphorus acid. Then, in the absence of OVA, the fluorescence of OVA-antibody modified NOP-CDs was quenched by GO via electrostatic attraction and pi-pi stacking interaction due to the FRET effect. The introduced OVA competed to displace the GO by special binding with the anti-OVA, resulting in the recovery of the fluorescence. This sensor displayed a linear response to OVA from 0.5 to 15 mu g/mL with a detection limit of 153 ng/mL and was successfully applied to the detection of the OVA sample with recoveries ranging from 99.25 to 118.90%. In summary, the green and easy-to-synthesize nano-material was used in this method, the accurate detection results, and the simple process exhibited the great potential of this method for practical applications. (c) 2018 Elsevier B.V. All rights reserved.