Chemometrics: an important tool for monitoring interactions of vitamin B7 with bovine serum albumin with the aim of developing an efficient biosensing system for the analysis of protein.

For the first time, interaction of vitamin B7 (VB7) with bovine serum albumin (BSA) was investigated with the aim of developing a method for the analysis of BSA. The interaction of VB7 with BSA was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV), and differential pulse voltammetry (DPV) at a multi-walled carbon nanotubes-modified glassy carbon electrode (MWCNTs/GCE). The recorded electrochemical data was combined with UVvis and fluorescence (F) spectroscopic data into a row- and column-wise augmented matrix and resolved by multivariate curve resolution-alternating least squares (MCR-ALS) as an efficient chemometric tool, and this assisted in the further elucidation of the above interaction. Also, with aid of MCR-BANDS method, the absence of rotational ambiguity was verified in the obtained results and we confirmed that the obtained results were unambiguous and reliable. The binding of VB7 to BSA was also modeled by molecular docking methods. Excellent agreement was found between the experimental and computational results. The differences of DPV responses of VB7 in the absence and presence of BSA (ΔI) were found to be linearly related to BSA concentration between 0.5×10(-9) mol L(-1) and 35.0×10(-9) mol L(-1), and a limit of detection (LOD, 3Sb/b) of 0.22×10(-9) mol L(-1) was calculated. Finally, the DPV method was further applied to the determination of serum albumin (SA) in serum samples obtained from Holstein cows and the results were in good agreement with those obtained by a medical diagnostic laboratory whose method was based on traditional cellulose acetate electrophoresis. The MWCNTs/GCE showed enhanced electron transfer kinetics, large electroactive surface area, and was highly sensitive, selective, and stable towards SA determination. The satisfactory analytical performance of the proposed method would make it potentially advantageous for a broad range of biosensing and clinical applications.