Birendra Kumar Yadav

Bio: Birendra Kumar Yadav is an academic researcher. The author has contributed to research in topics: Medicine & Internal medicine. The author has an hindex of 8, co-authored 9 publications receiving 334 citations.

Reduced graphene oxide modified smart conducting paper for cancer biosensor

Abstract: We report results of the studies relating to the fabrication of a paper based sensor comprising of poly (3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and reduced graphene oxide (RGO) composite. The effect of various solvents like methanol, ethylene glycol and H 2 SO 4 on the electrical conductivity of PEDOT:PSS coated Whatman paper has been investigated. The conductivity of this solution processed conducting paper significantly increases from ~1.16×10 −4 S cm −1 up to ~3.57×10 −2 S cm −1 (~300 times) on treatment with ethylene glycol. The observed significant increase in electrical conductivity is due to conformational rearrangement in the polymer and is due to strong non-covalent cooperative interaction between PEDOT and the cellulose molecules. Further, incorporation of RGO into the conducting paper results in improved electrochemical performance and signal stability. This paper electrode is a promising alternative over the expensive conventional electrodes (ITO, gold and glassy carbon), that are known to have limited application in smart point-of-care (POC) devices. This low cost, flexible and environment friendly conducting paper based biosensor utilized for cancer biomarker (carcinoembryonic antigen, CEA) detection reveals high sensitivity of 25.8 µA ng −1 mL cm −2 in the physiological range, 1–10 ng mL −1 .

Biofunctionalized Nanostructured Zirconia for Biomedical Application: A Smart Approach for Oral Cancer Detection

Abstract: Results of the studies are reported relating to application of the silanized nanostructured zirconia, electrophoretically deposited onto indium tin oxide (ITO) coated glass for covalent immobilization of the monoclonal antibodies (anti-CYFRA-21-1). This biosensing platform has been utilized for a simple, efficient, noninvasive, and label-free detection of oral cancer via cyclic voltammetry technique. The results of electrochemical response studies conducted on bovine serum albumin (BSA)/anti-CYFRA-21-1/3-aminopropyl triethoxy silane (APTES)/ZrO2/ITO immunoelectrode reveal that this immunoelectrode can be used to measure CYFRA-21-1 (oral cancer biomarker) concentration in saliva samples, with a high sensitivity of 2.2 mA mL ng-1, a linear detection range of 2-16 ng mL-1, and stability of six weeks. The results of these studies have been validated via enzyme-linked immunosorbent assay.

Highly sensitive protein functionalized nanostructured hafnium oxide based biosensing platform for non-invasive oral cancer detection

Abstract: We report results of the studies relating to the development of a non-invasive, label free immunosensor based on nanostructured hafnium oxide (hafinia) deposited onto indium tin oxide (ITO) coated glass for oral cancer biomarker (CYFRA-21-1) detection in human saliva. The nanostructured hafnia (nHfO2) has been synthesized via one step low temperature hydrothermal process and modified with 3-aminopropyltriethoxy silane (APTES) for covalent immobilization of monoclonal antibodies (anti-CYFRA-21-1). Bovine serum albumin (BSA) was used to block non-specific sites at the anti-CYFRA-21-1/APTES/nHfO2/ITO electrode surface. The structural, morphological and spectroscopic characterization of the synthesized nanomaterials and fabricated electrodes has been carried out using X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS) studies, respectively. The results of response studies conducted on BSA/anti-CYFRA-21-1/APTES/nHfO2/ITO immunoelectrode reveal that this biosensor has high sensitivity (9.28 μA mL ng−1 cm−2), wide linear detection range (2–18 ng mL−1) and fast response time (15 min). This immunosensor has been validated with enzyme linked immunosorbent assay (ELISA) in saliva samples of oral cancer patients.

Effect of Brownian motion on reduced agglomeration of nanostructured metal oxide towards development of efficient cancer biosensor.

Abstract: We report results of the studies relating to fabrication of nanostructured metal oxide (NMO) based cancer biosensor. With the help of 2D electroactive reduced graphene oxide (RGO), we successfully inhibited the Brownian motion of NMO that led to reduced agglomeration of NMO. The nanostructured hafnium oxide (nHfO2) was used as a model NMO. The reduced agglomeration of nHfO2 was achieved through controlled hydrothermal synthesis and investigated via nanoparticles tracking analysis (NTA). X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscope (TEM) techniques were used for phase identification as well as morphological analysis of the synthesized nanohybrid (nHfO2@RGO) material. The 3-aminopropyl triethoxysilane (APTES) was used for the functionalization of nHfO2@RGO and electrophoretic deposition (EPD) technique was used for its deposition onto ITO coated glass electrode. Further, antibodies of cancer biomarker (anti-CYFRA-21-1) were immobilized via EDC-NHS chemistry and Bovine serum albumin (BSA) was used for blocking of the non-specific binding sites. The electrochemical response studies of fabricated immunoelectrode (BSA/anti-CYFRA-21-1/APTES/nHfO2@RGO/ITO) revealed higher sensitivity (18.24µAmLng-1), wide linear detection range (0 to 30ngmL-1), with remarkable lower detection limit (0.16ngmL-1). The obtained results showed good agreement with the concentration of CYFRA-21-1 obtained through enzyme linked immunosorbent assay (ELISA) in saliva samples of oral cancer patients.

Protein functionalised self assembled monolayer based biosensor for colon cancer detection

Abstract: We report results of the studies relating to the fabrication of a surface plasmon resonance (SPR) based label-free immunosensor for real-time monitoring of endothelin-1 (ET-1), a colon cancer biomarker. A gold disk modified with a self-assembled monolayer (SAM) of 11-mercaptoundecanoic acid (11-MUA) was functionalised via covalent immobilization of monoclonal anti-ET-1 antibodies using EDC-NHS (1-(3-(dimethylamine)-propyl)-3-ethylcarbodiimide hydrochloride, N-hydroxy succinimide) chemistry. This immunosensing platform (ethanolamine/anti-ET-1/11-MUA/Au) was characterized via atomic force microscopy (AFM), contact angle (CA) and Fourier transform infrared (FT-IR) spectroscopic techniques. The fabricated SPR electrode was further used to detect ET-1 in the broad concentration range 2–100 pg mL−1, with a detection limit of 0.30 pg mL−1 and remarkable sensitivity of 2.18 mo pg−1mL. The adsorption mechanism was studied using monophasic model and the values of association (ka) and dissociation (kd) constants for anti-ET-1 and ET-1 binding were calculated to be 4.4 ± 0.4 × 105 M−1 s−1 and 2.04 ± 0.0003 × 10−3 s−1, respectively. The results obtained via analysis of serum samples of colorectal cancer patients were found to be in good agreement with those obtained from enzyme-linked immunosorbent assay (ELISA) technique. Further, electrochemical studies were performed to prove the efficacy of the fabricated platform as a point of care device for the detection of ET-1.

Graphene based sensors and biosensors

Abstract: Graphene has contributed to the fabrication of sensitive sensors and biosensors due to its physical and electrochemical properties. This review discusses the role of graphene and graphene related materials for the improvement of the analytical performance of sensors and biosensors. This paper also provides an overview of recent graphene based sensors and biosensors (2012–2016), comparing their analytical performance for application in clinical, environmental, and food sciences research, and comments on future and interesting research trends in this field.

Toward practical application of paper-based microfluidics for medical diagnostics: state-of-the-art and challenges.

Abstract: Microfluidic paper-based analytical devices (μPADs) have emerged as a promising diagnostic platform a decade ago. In contrast to highly active academic developments, their entry into real-life applications is still very limited. This discrepancy is attributed to the gap between research developments and their practical utility, particularly in the aspects of operational simplicity, long-term stability of devices, and associated equipment. On the basis of these backgrounds, this review attempts to: 1) identify the reasons for success of paper-based devices already in the market, 2) describe the current status and remaining issues of μPADs in terms of operational complexity, signal interpretation approaches, and storage stability, and 3) discuss the possibility of mass production based on established manufacturing technologies. Finally, the state-of-the-art in commercialisation of μPADs is discussed, and the “upgrades” required from a laboratory-based prototype to an end user device are demonstrated on a specific example.

Biofunctionalized two-dimensional Ti3C2 MXenes for ultrasensitive detection of cancer biomarker.

Abstract: In this work, ultrathin Ti3C2-MXene nanosheets were synthesized by minimally intensive layer delamination methods, and uniformly functionalized with aminosilane (f-Ti3C2-MXene) to provide a covalent binding for the immobilized bio-receptor (anti-CEA) for label free, ultrasensitive detection of cancer biomarker (carcinoembryonic antigen, CEA) The effect of different redox probes on the electrochemical behavior of f-Ti3C2-MXene was investigated and found that hexaammineruthenium ([Ru(NH3)6]3+) is the preferable redox probe for biosensing The fabricated biofunctionalized Ti3C2-MXene exhibits a linear detection range of 00001–2000 ng mL−1 with sensitivity of 379 µA ng−1 mL cm−2 per decade The wider linear detection range of our f-Ti3C2-MXene is not only higher than previously reported pristine 2D nanomaterials, but is even comparable to other hybrid 2D nanomaterials We believe that this work opens a new window for development of MXene-based highly sensitive DNA, aptamer, enzyme, antibody, and cell based biosensors, and could be further used in drug delivery application

An impedimetric biosensor based on electrophoretically assembled ZnO nanorods and carboxylated graphene nanoflakes on an indium tin oxide electrode for detection of the DNA of Escherichia coli O157:H7

Abstract: Aminopropyltrimethoxysilane (APTMS)-functionalized zinc oxide (ZnO) nanorods and carboxylated graphene nanoflakes (c-GNF) were used in a composite that was electrophoretically deposited on an indium tin oxide (ITO) coated glass substrate. The modified ITO electrodes were characterized using various microscopic and spectroscopic techniques which confirm the deposition of the APTMS-ZnO/c-GNF composite. The electrodes have been used for the covalent immobilization of an Escherichia coli O157:H7 (E. coli)-specific DNA prob. Impedimetric studies revealed that the gene sensor displays linear response in a wide range of target DNA concentration (10−16 M to 10−6 M) with a detection limit of 0.1 fM. The studies on the cross-reactivity to other water-borne pathogens show that the bioelectrode is highly specific.

Electrochemical Biosensors in Point‐of‐Care Devices: Recent Advances and Future Trends

Abstract: The use of biosensors in point-of-care (POC) testing devices has attracted considerable attention in the past few years, mainly because of their high specificity, portability, and relatively low cost. Coupling these devices with miniaturized electrochemical transducers has shown great potential toward simple, rapid, and cost-effective analysis that can be performed in the field, especially for healthcare, environmental monitoring, and food quality control. For this reason, the number of publications in this field has grown exponentially over the past decade, making it a trending topic in current research. Although great improvement has been achieved in the field of electrochemical biosensing, there are still some challenges to overcome, especially concerning the improvement of sensing materials and miniaturization. In this Review, we summarize some of the most recent advances achieved in POC electrochemical biosensor applications, focusing on new materials and modifiers for biorecognition developed to improve sensitivity, specificity, stability, and response time.