Leptospira interrogans Outer Membrane Protein-Based Nanohybrid Sensor for the Diagnosis of Leptospirosis

Abstract

Leptospirosis is an underestimated tropical disease caused by the pathogenic Leptospira species and responsible for several serious health problems. Here, we aimed to develop an ultrasensitive DNA biosensor for the rapid and on-site detection of the Loa22 gene of Leptospira interrogans using a gold nanoparticle–carbon nanofiber composite (AuN/CNF)-based screen-printed electrode. Cyclic voltammetry and electrochemical impedance were performed for electrochemical analysis. The sensitivity of the sensor was 5431.74 μA/cm2/ng with a LOD (detection limit) of 0.0077 ng/μL using cyclic voltammetry. The developed DNA biosensor was found highly specific to the Loa22 gene of L. interrogans, with a storage stability at 4 °C for 180 days and a 6% loss of the initial response. This DNA-based sensor only takes 30 min for rapid detection of the pathogen, with a higher specificity and sensitivity. The promising results obtained suggest the application of the developed sensor as a point of care device for the diagnosis of leptospirosis.

Graphene Oxide Nanoparticles Modified Paper Electrode as a Biosensing Platform for Detection of the htrA Gene of O. tsutsugamushi

“…This was due to the attractive forces between positively charged MB molecules, which intercalated to the DNA bases and the redox probe [Fe(CN) 6 ] 3−/4− . The ssGDNA of O. tsutsugamushi was hybridized to the sensor surface along with the methylene blue that has binding efficiency with the DNA bases [ 37 ] therefore speeding up the hybridization process. The MB bonded to the DNA bases enhanced the electron transfer and acted as a mediator in the electrochemical measurements using the redox probe.…”

Nanomaterial interfaces designed with different biorecognition elements for biosensing of key foodborne pathogens

“…Electrospun nanofibers are a good option to other polymeric nanomaterials because of their controllable thickness of fibers and ease of preparation. Electrospun nanocomposite nanofiber‐based electrodes could be obtained by using lots of types of other polymers, such as gelatin (Jiang et al., 2019), cellulose acetate (Abedalwafa et al., 2020), polyamide 6 (Migliorini et al., 2018), polyaniline (PANI) (Nag et al., 2021), polycaprolactone (PCL) (Yew et al., 2018), polydiacetylene/polyurethane (PDA/PU) (Kim et al., 2020), and carbon nanofibers (CNFs) (Verma et al., 2021). The electrochemical responses obtained using the electrospun nanofiber‐based biosensor for foodborne pathogen detection were well consistent with the conventional detection assay, with good stability, and reproducibility (Mercante et al., 2021).…”

Recent advances in the potential applications of luminescence-based, SPR-based, and carbon-based biosensors

“…The biosensor uses a gold nanoparticle–carbon nanofiber composite-based screen-printed electrode. The authors claimed that the DNA-based biosensor provided a rapid detection of the pathogen with a higher selectivity and specificity (Verma et al 2021 ).…”