Neeraj Kumar; V. Sorna Gowri; Pushpesh Ranjan; Mohd. Abubakar Sadique; Shalu Yadav; Ayushi Singhal; Alka Mishra; S. Murali; Raju Khan
Abstract
Oral tumours are the sixth most incessant infection with high mortality and morbidity rates in human beings and they pose a serious threat worldwide owing to their soaring case-fatality rate and metastatic characteristics of spreading to other parts of the body. Nanomaterials as of late have become indispensable ...
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Oral tumours are the sixth most incessant infection with high mortality and morbidity rates in human beings and they pose a serious threat worldwide owing to their soaring case-fatality rate and metastatic characteristics of spreading to other parts of the body. Nanomaterials as of late have become indispensable components for biosensor platforms due to their fantastic mechanical, electronic, and optical properties. Specific emphasis is laid in this review on electrochemical biosensors working at the molecular levels, which can be classified into mainly three groups i.e., DNA biosensors, RNA biosensors, and protein biosensors as indicated by the type of the analytes. The carbon-based and non-carbon-based nanomaterials utilizing electrochemical procedures for recognizing oral cancer biomarkers are also reviewed. An extensive review has been made to cover ongoing advancements in the field of nanomaterials based as electrochemical biosensors. This study mostly sums up the significant electrochemical methods, the ongoing advancements of electrochemical technique-based biosensor frameworks for the discovery of oral cancer biomarkers. This effort aims to provide the reader with a concise view of new advances in areas on oral cancer biomarkers for electrochemical signal amplification and the innovative electroanalytical techniques which have been utilized in the miniaturization and integration of the sensors.
Bhavna H. Meshram; Subhash B. Kondawar
Abstract
Fabrication of nanocomposite film of electrically conducting polypyrrole (PPy) and functionalized multi-walled carbon nanotubes (MWCNTs) on a stainless steel electrode by electro-deposition method and immobilization of urease onto the nanocomposite film to obtain a nanobiocomposite electrode as a sensitive ...
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Fabrication of nanocomposite film of electrically conducting polypyrrole (PPy) and functionalized multi-walled carbon nanotubes (MWCNTs) on a stainless steel electrode by electro-deposition method and immobilization of urease onto the nanocomposite film to obtain a nanobiocomposite electrode as a sensitive electrochemical urease biosensor is reported. Cross-linking by glutaraldehyde (0.1%) method for the immobilization of urease (2 mg/mL) in a phosphate buffer solution of 0.1 molarity at a pH of 7.0 was used. The Characterization of the nanocomposite and nanobiocomposite film thus obtained was done by Scanning Electron Microscopy (SEM), Fourier Transform Infrared spectroscopy (FTIR), Cyclic Voltammetry (CV), and Electrochemical Impedance Spectroscopy (EIS). The increased size of the Cyclic voltammogram and shifting of anionic peaks towards the lower voltage indicates the incorporation of MWCNTs into the growing film during the electro-deposition of PPy on electrode. Reduction of the oxidation potential due to MWCNTs leads to lowering of potential for the electro-catalytic reduction of urea. The incorporation of functionalized MWCNT also made possible increased amount of enzyme concentration, an extended lifetime, long time stability and improved response times of the enzyme electrode. This modified nanobiocomposite electrode showed a good linear response to the urea concentration change in the range of 10 mM to 50 mM. The results obtained from Michaelis–Menten constant K´m, maximum current (Imax), detection limit, sensitivity, response time and shelf-life of electrochemical biosensor indicating good sensing for urea detection.

Gounder Thangamani J.; Kalim Deshmukh; Kishor Kumar Sadasivuni; K. Chidambaram; M. Basheer Ahamed; Deepalekshmi Ponnamma; Mariam Al-Ali AlMaadeed; S. K. Khadheer Pasha
Abstract
Graphene and carbon nanotubes (CNTs) based sensors have been extensively studied because of their applications in the detection of various chemicals and biomolecules. From an application point of view, high sensitivity and selectivity is a promising tool for fast detection of gas leakage and early diagnosis ...
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Graphene and carbon nanotubes (CNTs) based sensors have been extensively studied because of their applications in the detection of various chemicals and biomolecules. From an application point of view, high sensitivity and selectivity is a promising tool for fast detection of gas leakage and early diagnosis of diseases for health care. In the present review article, we provide a comprehensive overview on the recent advances in the development of graphene and CNT based electrochemical biosensors and gas sensors. From the future point of view, special attention is paid to the synthesis techniques for high-performance biosensors and gas sensors. This article focuses on detecting mechanism for various volatile organic compounds (VOCs) gas sensing behavior of the graphene and CNT based sensors. A comparative study of the sensing behavior of pure metal oxide nanoparticles as well as their hybrids with graphene and CNTs has been reported.