MOLECULAR IMPRINTING OF SMALL MOLECULES WITH ORGANIC SILANES - FLUORESCENCE DETECTION

Small molecules, peptides, and proteins can be imprinted using mixture s of organic silanes. Molecular imprints may serve as artificial recep tors, i.e., biosensor sensing elements for detection of chemical and b iological toxins, drugs, and environmental hazards. One method for det ection of imprint-bound molecules is fluorescence. Molecular imprints to N-acetyltryptophanamide (NATA) and fluorescein were prepared, and t heir respective binding constants determined using steady-state fluore scence spectroscopy. Stern-Volmer fluorescence quenching plots of impr int-bound molecules using potassium iodide (KI) and acrylamide indicat e bound molecules are shielded from the solvent environment. Scatchard plot analysis revealed two binding affinities, i.e., a K-d = 0.13 and 2.5 mu M for NATA binding to NATA imprints. Interestingly, NATA exhib ited higher affinity, i.e., K-d = 1.3 and 35 nM, for the fluorescein i mprint. These data support the usefulness of fluorescence techniques i n molecular imprint-based detection technology.