Immobilization of horseradish peroxidase on UiO-66-NH2 for colorimetric and fluorometric sensing of nitrite

. The kit could visually identify nitrite from 10-400 μM in colorimetric mode and 0-400 μM in fluorometric mode. This method provides an innovative approach for nitrite sensing, paving the way for new research into multifunctional immobilized enzymes and their potential uses in biochemical sensing applications.