Fingolimod interacted with the human serum albumin using hydrophobic forces

Human serum albumin (HSA) has many physiological functions due to its high capacity as a carrier and as a reservoir for molecules such as fatty acids, nutrients and drugs. Fingolimod is the first oral therapy drug that approved by FDA for relapsing-remitting multiple sclerosis (RRMS) [1]. Interaction between human serum albumin (HSA) and Fingolimod has been investigated using spectroscopic methods. UV-vis spectrum of enhanced concentration of fingolimod was studied and the results showed an absorption enhancement in wavelength of 278 nm along with a shift from 278 to 275nm. According to the results the complex formation occurs and the change in HSA conformation following the complexation leads to maximum wavelength change. Fluorescence quenching titrationsin physiologic conditions (i.e pH 7.4), showed that tryptophan emission of HSA is quenched by the addition of enhanced concentrations of fingolimod which showed that fingolimod interacted with HSA and drug-HSA complexes, following the drug addition to the HSA solution. The results suggested well interaction between fingolimod and HSA. Accordingly the combined therapies should be administered with cautions to avoid unwanted variations in drug free fractions in blood. In additions the tendency of fingolimod to HSA could be regarded as a possible root for better drug delivery using albumin as a carrier in the future studies [2,3].