Interactions of cannabinoids with bovine serum albumin.

There is no shift of emission maximum (F470nm) of bovine serum albumin (BSA)-1-anilino-8-naphthalene sulphonic acid (ANS) complex in the presence of delta-9-tetrahydrocannabinol (delta-9-THC) alone and cannabidiol (CBD) or cannabinol (CBN) in the presence and absence of delta-9-THC. Delta-9-THC (1.66-13.33 microM) and CBD at higher concentrations (13.33-20.0 microM) produce a concentration-dependent significant quenching of fluorescence of BSA-ANS complex, but CBN (1.66-20.0 microM) as well as CBD at lower concentrations (1.66-6.66 microM) fails to produce any significant change in fluorescence intensity under similar conditions. Furthermore, neither CBD nor CBN is able to affect the delta-9-THC-induced quenching of fluorescence intensity of BSA-ANS complex. These results indicate that the binding of cannabinoids to the ANS binding sites of BSA molecule are in the order delta-9-THC greater than CBD greater than CBN, and CBD or CBN does not have any influence on the binding of delta-9-THC to BSA molecules under these conditions.