Characterization of paracetamol binding with normal and glycated human serum albumin assayed by a new electrochemical method

Abstract

No presente estudo, as interações entre paracetamol (PC) e albumina sérica humana, nas formas não glicada (HSA) e glicada (GHSA), foram investigadas por meio de voltametria cíclica contínua em tampão acetato, pH 7,4. Os resultados mostraram ausência de mudanças significativas no potencial formal E 0 e na constante de velocidade de transferência de elétrons, no eletrodo, k s , do PC. O decaimento na corrente do fármaco, após a adição de proteína, mostrou um decréscimo na concentração da droga livre e formação de um biocomplexo. Coulometria foi também usada para determinar os parâmetros de ligação. A constante de ligação e relação de ligação para HSA e GHSA foram 2,0×10 4 and 7,8×10 3 mol L -1 , respectivamente, e o número de ligações foi 2:1 para HSA-PC e 1:1 para GHSA-PC. Estes resultados foram confirmados por espectroscopia UVVis. Assim, o novo método de análise eletroquímica descrito é fácil e rápido para avaliação das interações droga-proteína com implicação clínica significativa em diabetes.In the present study the interactions between paracetamol (PC) and human serum albumin, in non-glycated (HSA) and glycated form (GHSA), were investigated using continuous cyclic voltammetry in acetate buffer pH 7.4. The results showed lack of significant changes in formal potential E 0 and electrode reaction constant rate, k s , of PC. The decay in the drug current, after the addition of protein, showed a decrease in free drug concentration and formation of a biocomplex. The contentious coulometry was also used to determine the binding parameters. The binding constant and binding ratio for HSA and GHSA were 2.0×10 4 and 7.8×10 3 mol L -1, respectively, and the number of binding was 2:1 for HSA-PC and 1:1 for GHSA-PC. These results were confirmed by UV-Vis spectroscopy. Thus, the new electrochemical analysis method described here provides an easy and fast method for evaluation of drug-protein interactions with significant clinical implication in diabetes.

Interaction of a novel platinum drug with bovine serum albumin: FTIR and UV-Vis spectroscopy analysis

“…22,37 The observed hyperchromic effect may also be suggestive of an increase in the exposure of tryptophan to the solvent. 38 Prior to the determination of the binding constant of Pt-Blue as 1.20 Â 10 5 M À1 (Fig. 3 inset), the absorption data is corrected since the Pt-Blue complex has a high absorption at low R values in the same region (Fig.…”

Morphological Analysis and Interaction of Chlorophyll and BSA

“…Hyperchromism effect was observed with increasing Chl concentration in BSA. This effect can be associated with the interaction of BSA with Chl and may be indicative of an increase in exposure of tryptophan to the solvent [ 21 , 32 ] due to a conformational change in the protein [ 33 ].…”

Ascorbic Acid and BSA Protein in Solution and Films: Interaction and Surface Morphological Structure

“…We have observed a hyperchromism with increasing AA concentration in BSA. This effect can be associated to interaction of BSA with AA [4, 13, 14] and may be indicative of an increase in exposure of tryptophan to the solvent [15] due to a conformational change in the protein [12]. …”