RAMAN AND SERS SPECTROSCOPY MONITORING THE INTERACTION MECHANISM OF QUINOLINE-DERIVED ANTIMALARIAL DRUGS WITH HEMATIN

Simona Cîntǎ Pînzaru1, N. Peica2, B. Küstner2, S. Schlücker2, M. Schmitt3, T. Frosch3, J. Popp3, W. Kiefer2

1Molecular Spectroscopy Department, Babes-Bolyai University, Kogălniceanu 1, RO-400084 Cluj-Napoca, Romania
2Institut für Physikalische Chemie, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany
3Institut für Physikalische Chemie, Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany

Two quinoline-derived antimalarial drugs, namely chloroquine (Nivaquine) and mefloquine (Lariam) (Fig. 1) were employed for the vibrational Raman and SERS investigations in order to get insight into their antimalarial interaction mechanism with the hematin. Strong chemisorption through the quinoline skeletal part of each molecular structure with respect to the metal surface was concluded. Different hematin-antimalarial drug chemical systems were prepared and NIR-SERS investigated. Differences between the interaction mechanisms of the two drugs with the non-resonant excited hematin are discussed. The perturbed adsorption geometries of the two drugs were observed in the presence of hematin. The adsorption processes of these molecular species monitored by Raman and SERS spectroscopy provided more insight into the complex antimalarial mechanism1.

Fig. 1. FT-Raman spectra of chloroquine diphosphate and mefloquine hydrochloride. 
Excitation: 1064 nm, 800 mW.

1. Pagola S.; Stephens P.W.; Bohle D.S.; Kosar A.D.; Madsen S.K., Nature, 404, 6775, 307,2000.