Biology subjects

Brito, W.

Publications and source records attributed to Brito, W..

3 recordsLinked to original sources

bioRxiv2024

Electrochemical Biosensor Using Polymer Nanocomposites for G6PD Deficiency Detection

Electrochemical biosensors based on the combination of DHP, OG, AuNPs, and G6PD, used to determine the enzymatic activity of G6PD, showed optimal current intensity values close to pH 7.8 at room temperature. Square wave voltammetry was optimized and used to evaluate the responses of the biosensors during the enzymatic reaction and construct the analytical curves. The best results were found under the following conditions: 30 minutes of incubation, in the range of NAD+ concentrations from 0.75 to 6 mol L-1; obtaining coefficient of determination (R2) values between 98 and 99% about the analytical curves. The biosensors maintained their stability after five days of storage. The calculated LOD and LOQ limits showed good sensitivity of the method, achieving results in the order of 10-6 mol L-1.

bioengineering↗

bioRxiv2024

Carboxylated graphene: A novel approach for enhanced IgA-SARS-CoV-2 electrochemical biosensing

Biosensors comprise devices that use a material of biological nature as receptors connected to transducers, these devices are capable of capturing biorecognition signals, called a primary signal, and converting it to a measurable signal. In this study, we report the synthesis of carboxylated graphene (CG) through a carboxylation method in acid medium and further characterization of the materials by different techniques such as scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy, thermal gravimetric analysis (TGA), and X-ray diffraction (DRX). Also, the surface of the screen-printed carbon electrodes (SPCEs) was modified with CG for subsequent immobilization of N-protein of SARS-CoV-2, which allowed the detection of antibodies (IgA-SARS-CoV-2). The electrical properties and response of the biosensor were investigated using electrochemical techniques (cyclic voltammetry and electrochemical impedance spectroscopy). Through the chemical characterization techniques, it was possible to confirm the success of the CG synthesis process. The biosensor fabricated shown to be able to detect IgA-SARS-CoV-2 in the range of 1:1000 to1:200 v/v in phosphate buffer solution (PBS) and the limit of detection calculated was 1:1601 v/v. this perspective they comprise a wide range of applications due to its advantages, such as the possibility of a shorter response time, reproducibility, the miniaturization of detection devices such as the use of screen-printed electrodes, the use of small amounts of sample, the high sensitivity and specificity, low limits of detection and the integration of nano materials that make it possible to improve the detected signal.

bioengineering↗

bioRxiv2024

Electrospun Poly(ε-caprolactone) Membranes Modified with Heparin and Essential Fatty Acids for Biomedical Applications

The study aimed to enhance wound healing by modifying poly({varepsilon}-caprolactone) (PCL) membranes with sodium heparin (HS) and Essential Fatty Acids (EFA). Electrospinning was used to prepare the membranes containing the maximum concentration of HS and AGE, which were then sterilized with ozone. Microbiological tests confirmed effective sterilization. The membrane characterization included scanning electron microscopy (SEM) for morphological analysis, wettability studies for contact angle determination, Fourier-transform infrared spectroscopy (FT-IR) analysis, and thermogravimetry (TGA) for thermal analysis. Results indicated successful preparation and sterilization of PCL membranes modified with HS and EFA. Morphological analysis showed well-formed and randomly distributed fibers, although the PCL+HS membrane exhibited beads on its fibers. Adding HS and EFA affected the fiber diameter, with PCL+HS fibers having a smaller diameter than pure PCL and PCL+EFA fibers. Wettability analysis demonstrated modified surface properties with reduced contact angles. FT-IR analysis showed slight contributions of HS and EFA in the modified PCL membranes, while thermal analysis revealed no substantial changes in thermal stability. In conclusion, PCL membranes modified with HS and EFA can potentially accelerate wound healing, presenting an innovative and cost-effective approach to treating skin injuries.

bioengineering↗