Inclusion complexation of novocaine by beta-cyclodextrin in aqueous solutions.
The formation of inclusion complexes between beta-cyclodextrin (beta-CD) and the local anesthetic 2-(diethylamino)ethyl-p-amino-benzoate (novocaine) in aqueous solutions under different acidity conditions, using steady-state fluorescence or UV-vis spectroscopies, electrical conductivity, or the kinetic study of both the nitrosation reaction of the primary amine group in a mild acid medium and the hydrolysis of the ester function under an alkaline medium, has been studied. The inclusion complex formation between neutral or protonated novocaine and beta-CD of 1:1 stoichiometry was observed; however, the magnitude of the binding constants depends on the nature of both the guest and the host, and the higher-affinity guest-host was found under conditions when both the novocaine and the beta-CD were neutral molecules.
Iglesias
Emilia
E
Departamento de Química Física e E. Q. I, Facultad de Ciencias, Universidad de La Coruña, 15071-La Coruña, Spain. qfemilia@udc.es
D004337:Drug Carriers / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D011343:Procaine / Q000737:chemistry*; D012995:Solubility; D012996:Solutions; D047392:beta-Cyclodextrins / Q000737:chemistry*
D004337:Drug Carriers; D012996:Solutions; D047392:beta-Cyclodextrins; D011343:Procaine