Construction of a dual colorimetric fluorescent imprinting polymer hybrid system for the detection of alpha-fetoprotein based on the multi-FRET effect and modeling of its color response mechanism

The hybrid ratiometric fluorescence sensors (GKHMIPs & RKHMIPs) encompass luminescent substances incorporated within a core-shell architecture. These sensors manifest a diverse array of hues in response to variations in the concentration of alpha-fetoprotein, accomplished through disparities in the quantum dots (QDs)-protein response. This study is devoted to comprehending the principles governing the alteration of fluorescence during the recognition process of the ratiometric fluorescence sensor. A compensation mechanism, rooted in the correlation between fluorescence and protein response, is postulated through a fluorescence interaction model (multi-FRET model). Multi-FRET model can be divided into FRET process and Fluorescence compensate process (FCP), FCP occurs when electron orbits are filled, hindering the fluorescence resonance energy transfer process and leading to the return of excited state electrons to the ground state by alternative pathways. Based on the multi-FRET model we demonstrate the Sherpa formular to calculating the fluorescence-target relation. To assess the visual impact, the CIE-Lab model is introduced to validate the rationale behind the multi-color colorimetric model. The influence of different mixing ratios on the visualization effect is elucidated using the concentration fluorescence response model, and the optimal relationship between wavelength combinations in the tricolor mixing model is proposed.