A novel electrochemical immunosensor for the determination of tuberculosis diagnosis exploiting graphene-affinity peptide

• Published in: Talanta (Oxford) 2025-02, Vol.283, p.127146, Article 127146
• Main Authors: Braz, Beatriz A., Hospinal-Santiani, Manuel, Martins, Gustavo, Moscardi, Ana P.Z., Beirão, Breno C.B., Soccol, Carlos R., Thomaz-Soccol, Vanete, Bergamini, Márcio F., Marcolino-Junior, Luiz H.
• Format: Article
• Language: English
• Subjects: Antibodies, Bacterial - blood; Antibodies, Bacterial - chemistry; Antibodies, Bacterial - immunology; Biosensing Techniques - methods; Electrochemical immunosensor; Electrochemical Techniques - methods; Electrodes; Graphite - chemistry; Humans; Immunoassay - methods; Lab-made electrode; Limit of Detection; Mycobacterium tuberculosis - immunology; Peptides - chemistry; Peptides - immunology; Solid-binding peptide; Tuberculosis; Tuberculosis - blood; Tuberculosis - diagnosis
• ISSN: 0039-9140; 1873-3573; 1873-3573
• DOI: 10.1016/j.talanta.2024.127146

Conventional methods for diagnosing tuberculosis (TB), a significant global health challenge, often have drawbacks like time-consuming procedures, limited sensitivity, and the need for complex, expensive infrastructure. Hence, the development of electrochemical immunosensors has emerged as a promising strategy for TB detection due to their simplicity, speed, sensitivity, portability, and cost-effectiveness. In this study, we developed a rapid, simple, and low-cost immunosensor using a lab-made screen-printed electrode (SPE) based on the peptide TB 68-G as a recognition site. This synthetic peptide is composed of two important parts, one with an affinity for graphene materials and the other able to interact with anti-M. tuberculosis antibodies. This structural configuration allows for effective modification of the electrode surface while maintaining the ability to recognize the target. The proposed label-free electrochemical immunosensor was tested against M. tuberculosis antibodies and demonstrated a detection limit of 192 ng mL−1 with an R2 value of 0.98. The diagnostic platform exhibited selectivity against nonspecific antibodies and successfully differentiated between negative and positive human serum samples with a 95 % confidence interval. This simple and affordable immunosensor holds great potential to impact TB control by enabling effective detection and improving disease surveillance. [Display omitted] •Innovative tuberculosis detection strategy characterized by its simplicity, sensitivity, and portability.•Tuberculosis antibodies using graphene-binding peptide as the recognition site, ensuring specificity and accuracy.•Screen-printed electrode as a disposable platform for the TB immunosensor, enhancing affordability and accessibility.•Point-of-Care device for trials of relevant diseases, paving the way for improved diagnostic tools in healthcare settings.