Rapid determination of amylopectin content in starch using molecular rotor fluorescent probes

This study optimized fluorescence detection conditions for CCVJ and DCVJ molecular rotors, establishing optimal excitation wavelengths (430 nm for CCVJ and 460 nm for DCVJ), probe concentrations (0.019 mM for CCVJ and 0.032 mM for DCVJ), buffer concentrations (5 mM for CCVJ and 10 mM for DCVJ), and pH values (7 for CCVJ and 4 for DCVJ), all at a detection temperature of 25 °C. These optimized conditions were then used to evaluate the efficacy of the rotors in amylopectin quantification. A linear relationship between amylopectin concentration and fluorescence intensity was observed within specific ranges. The molecular rotor methods were compared with iodine colorimetric and concanavalin A methods, demonstrating improved accuracy over iodine colorimetric method. The rotors showed sensitivity to Fe³⁺ and Fe²⁺ interference but resilience to other substances. In dilute solutions, fluorescence response was primarily influenced by starch molecular structure rather than viscosity. The CCVJ method's applicability was validated using bean samples, yielding results comparable to the concanavalin A method in accuracy and precision. This study demonstrates the potential of molecular rotors as effective tools for amylopectin quantification in both research and industrial applications.