Self-Enriching Electrospun Biosensors for Impedimetric Sensing of Zika Virus

• Published in: ACS applied materials & interfaces Vol. 14; no. 1; pp. 41 - 48
• Main Authors: Frias, Isaac A. M, Vega Gonzales Gil, Laura Helena, Cordeiro, Marli T, Oliveira, Maria D. L, Andrade, Cesar A. S
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 12-01-2022
• Subjects: Alginates - chemistry; Aniline Compounds - chemistry; Animals; Antibodies, Immobilized - immunology; Antibodies, Viral - immunology; Biological and Medical Applications of Materials and Interfaces; Biosensing Techniques - methods; Blood - virology; Chlorocebus aethiops; Electrochemical Techniques; Hydrogels - chemistry; Immunoassay - methods; Limit of Detection; Nanofibers - chemistry; Vero Cells; Viral Load - methods; Zika Virus - immunology; Zika Virus - isolation & purification; ZIKV; label-free detection; viral detection; electrospun nanofibers; polyaniline; electrochemical biosensor
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.1c14052

Zika virus (ZIKV) infection is associated with the Guillain–Barré syndrome, and when non-vector congenital transmission occurs, fetal brain abnormalities are expected. After ZIKV infection, the blood, breast milk, and other body fluids contain low viral loads. Their detection is challenging as it requires the processing of larger input volumes of the clinical samples. Pre-enrichment is a valuable strategy to increase the analyte concentration. Therefore, the authors propose the use of a hierarchal composite polyaniline-(electrospun nanofiber) hydrogel mat (ENM) for the simultaneous enrichment and impedimetric sensing of ZIKV viral particles. The electrospinning conditions of polyvinyl alcohol and alginate, including blend formulation, were optimized through a factorial design. Disintegration and gelatinization were controlled via cross-linking to improve the hydrogel properties. Hierarchization was achieved by in situ chemical deposition of conductive polyaniline. The carboxyl groups of the ENM were used for the covalent immobilization of anti-ZIKV polyclonal antibodies used in the specific recognition of ZIKV within the medium of Vero cell culture. The specific capture and desorption of virions were studied at different pHs. ENMs were characterized by scanning electron microscopy and FTIR. Atomic force microscopy along with UV–vis and electrochemical impedance spectroscopies was used to monitor the antibody immobilization, ZIKV capture, and elution processes. Our results show that 14.2 mg (0.25 cm3) of ENM can capture 38.7 ± 2.5 μg of ZIKV with a desorption rate of 99.97% (38.29 ± 2.7 μg ZIKV), which is reusable for at least three times. Therefore, the capture capacity (micrograms of ZIKV captured per milligram of ENM) of polyaniline-hierarchized mats was 2.72 μg ZIKV/mg. The impedance LOD value was determined to be 2.76 μg of ZIKV particles (approximately 6.6 × 103 PFU/mL). As a result, we present a fast small-scale purification system that can simultaneously monitor ZIKV electrochemically and optically.