Editor-in-Chief
Hatice Kübra Elçioğlu
Vice Editors
Levent Kabasakal
Esra Tatar
Online ISSN
2630-6344
Publisher
Marmara University
Frequency
Bimonthly (Six issues / year)
Abbreviation
J.Res.Pharm.
Former Name
Marmara Pharmaceutical Journal
Journal of Research in Pharmacy
2024 , Vol 28 , Issue 1
Investigation of the letrozole interaction with human serum albumin using a combination of MCR-ALS chemometrics, multi-spectrometric and molecular modeling
1Department of Drug applied research center, Faculty of Pharmacy, Tabriz University of Medical Sciences University, Tabriz, Iran2Department of Pharmaceutical analysis research center, Tabriz University of Medical Sciences University, Tabriz, Iran
3Department of materials, Norwegian University of Sciences and Technology (NTNU), NO-7491 Trondheim, Norway
4Department of Biochemistry, Faculty of Sciences, Payame Noor University, Tehran, Iran DOI : 10.29228/jrp.667 Letrozole-HSA (human serum albumin) binding was studied using various spectroscopic techniques, MCR-ALS (multivariate curve resolution alternating least squares) chemometrics method, and molecular modelings. Binding constant at different temperatures, main interacted sites properties, thermodynamic parameters, HSA conformation in complex form was obtained using the relevant data. Due to the fluorescence emission wavelength overlap of LET and HSA, fluorescence emission enhancement was seen at the emission wavelength of 340 nm, following the excitation at 278 nm rather than fluorescence quenching. MCR-ALS analysis of UV-Vis absorption and fluorescence emission data approved the complex formation between LET and HSA. The fluorescence emission quenching was observed at 320 nm rather than 340 nm. The emission data were fitted to the Stern-Volmer, van't Hoff, and Hill models to calculate the quenching and binding constants. The results showed that LET binds to HSA with a binding constant of 2.25 × 104 M-1 that resembles the moderate binding capacity of LET to HSA. Furthermore, decreased biding constant at higher temperatures and decreased quenching constants at higher temperatures showed static quenching constant.
Thermodynamic analysis and simultaneous competitive binding studies showed that LET interacts with HSA's subdomain IIA and IIIA mainly by hydrogen and Van der Waals bonds. The results agree with molecular modeling studies. FTIR and circular dichroism (CD) results revealed the reduced alpha-helical structure of HSA in LET-HSA complex compared to non-bound form.
Keywords : Letrozole; Human serum albumin; spectroscopy; MCR-ALS; Emission spectra overlap