Determining the binding affinity and binding site of bensulfuron-methyl to human serum albumin by quenching of the intrinsic tryptophan fluorescence

Competitive binding of Chlorin p6 and Dansyl-l-Proline to Sudlow’s site II of human serum albumin

“…The binding specificities of the pockets are determined by their shapes and the particular distributions of basic and polar residues on the largely hydrophobic interior walls that are involved in charge neutralization and hydrogen bonding interactions with acidic or electronegative small molecule ligands. Before, the specific binding of two chlorin derivatives (chlorin p 6 and purpurin 18) to Sudlow's site I of Human Serum Albumin (HSA) has been studied by monitoring the intrinsic fluorescence of the single tryptophanyl residue at 214 (Trp-214) [21,22]. The number of binding sites for chlorin p 6 is found to be 1.4, which suggests that the photosensitizer binds to more than one site in HSA.…”

“…In the present report, the binding of chlorin p 6 to the vicinity of Sudlow's site II has been studied by using steady-state, time resolved and stopped-flow fluorescence techniques. For this purpose, we have monitored the competitive binding of chlorin p 6 with Dansyl-L-Proline, as it is known that this molecule binds specifically to the Sudlow's site II of Human Serum Albumin (HSA) [19][20][21][22][23][24][25]. This study serves to provide an understanding of the specific binding of the photosensitizer to the albumin.…”

Can Chiroptical Spectroscopy be Used for the Analysis of Blood Plasma?

“…Although blood plasma is a complex system of many chemical substances from low to high molecular weight, this ECD pattern mainly reflected the high content of human serum albumin HSA (68.5 kDa, 40–50 g/l in the plasma)—the protein having large amount of α‐helical conformation . This interpretation was supported by the relative intensities of both the ECD bands (the band at ~210 nm was more intense than the band at ~219 nm) . However, as far we as know, albumin itself or its conformational changes have not played a crucial role in degenerative and cancer diseases for the diagnosis of which the methods of molecular spectroscopy have most frequently been tested.…”

“…11 This interpretation was supported by the relative intensities of both the ECD bands (the band at~210 nm was more intense than the band at~219 nm). 17 However, as far we as know, albumin itself or its conformational changes have not played a crucial role in degenerative and cancer diseases for the diagnosis of which the methods of molecular spectroscopy have most frequently been tested. Therefore, we tried to remove it by ultrafiltration to see the other components of the plasma.…”

Comparative Interactions of Dihydroquinazolin Derivatives with Human Serum Albumin Observed via Multiple Spectroscopy

“…Interaction studies of HSA with biological molecules can elucidate the properties of the drug-protein complex because they may provide useful information about the structural features that determine the therapeutic effectiveness of drugs. Therefore, various studies on the interactions between HSA and small bioactive molecules have been reported over the years [16][17][18][19][20]. Generally, strong binding to HSA will decrease the concentrations of a free drug in plasma, whereas weak binding will reduce the duration of drug action.…”