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This study utilized faradaic and non-faradaic electrochemical impedance spectroscopy to detect alpha synuclein amyloid fibrils on gold interdigitated tetraelectrodes (AuIDTE), providing valuable insights into electrochemical reactions for clinical use. AuIDE was purchased, modified with zinc oxide for increased hydrophobicity. Functionalization was conducted with hexacyanidoferrate and carbonyldiimidazole. Faradaic electrochemical impedance spectroscopy has been extensively explored in clinical diagnostics and biomedical research, providing information on the performance and stability of electrochemical biosensors. This understanding can help develop more sensitive, selective, and reliable biosensing platforms for the detection of clinically relevant analytes like biomarkers, proteins, and nucleic acids. Non-faradaic electrochemical impedance spectroscopy measures the interfacial capacitance at the electrode-electrolyte interface, eliminating the need for redox-active species and simplifying experimental setups. It has practical implications in clinical settings, like real-time detection and monitoring of biomolecules and biomarkers by tracking changes in interfacial capacitance. The limit of detection (LOD) for normal alpha synuclein in faradaic mode is 2.39-fM, The LOD for aggregated alpha synuclein detection is 1.82-fM. The LOD for non-faradaic detection of normal alpha synuclein is 2.22-fM, and the LOD for nonfaradaic detection of aggregated alpha synuclein is 2.40-fM. The proposed EIS-based AuIDTEs sensor detects alpha synuclein amyloid fibrils and it is highly sensitive., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The substantial nutritional content and diversified biological activity of plant-based nutraceuticals are due to polyphenolic chemicals. These chemicals are important and well-studied plant secondary metabolites. Their protein interactions are extensively studied. This relationship is crucial for the logical development of functional food and for enhancing the availability and usefulness of polyphenols. This study highlights the influence of protein types and polyphenols on the interaction, where the chemical bindings predominantly consist of hydrophobic interactions and hydrogen bonds. The interaction between polyphenolic compounds (PCs) and digestive enzymes concerning their inhibitory activity has not been fully studied. Therefore, we have examined the interaction of four digestive enzymes (α-amylase, pepsin, trypsin, and α-chymotrypsin) with four PCs (curcumin, diosmin, morin, and 2',3',4'-trihydroxychalcone) through in silico and in vitro approaches. In vitro plate assays, enzyme kinetics, spectroscopic assays, molecular docking, and simulations were performed. We observed all these PCs have significant docking scores and preferable interaction with the active site of the digestive enzymes, resulting in the reduction of enzyme activity. The enzyme-substrate binding mechanism was determined using the Lineweaver Burk plot, indicating that the inhibition occurred competitively. Among four PCs diosmin and morin has the highest interaction energy over digestive enzymes with IC 50 value of 1.13 ± 0.0047 and 1.086 ± 0.0131 μM. Kinetic studies show that selected PCs inhibited pepsin, trypsin, and chymotrypsin competitively and inhibited amylase in a non-competitive manner, especially by 2',3',4'-trihydroxychalcone. This study offers insights into the mechanisms by which the selected PCs inhibit the enzymes and has the potential to enhance the application of curcumin, diosmin, morin, and 2',3',4'-trihydroxychalcone as natural inhibitors of digestive enzymes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Troponin I is a protein released into the human blood circulation and a commonly used biomarker due to its sensitivity and specificity in diagnosing myocardial injury. When heart injury occurs, elevated troponin Troponin I levels are released into the bloodstream. The biomarker is a strong and reliable indicator of myocardial injury in a person, with immediate treatment required. For electrochemical sensing of Troponin I, a quadruplet 3D laser-scribed graphene/molybdenum disulphide functionalised N 2 -doped graphene quantum dots hybrid with lignin-based Ag-nanoparticles (3D LSG/MoS 2 /N-GQDs/L-Ag NPs) was fabricated using a hydrothermal process as an enhanced quadruplet substrate. Hybrid MoS 2 nanoflower (H3 NF) and nanosphere (H3 NS) were formed independently by varying MoS 2 precursors and were grown on 3D LSG uniformly without severe stacking and restacking issues, and characterized by morphological, physical, and structural analyses with the N-GQDs and Ag NPs evenly distributed on 3D LSG/MoS 2 surface by covalent bonding. The selective capture of and specific interaction with Troponin I by the biotinylated aptamer probe on the bio-electrode, resulted in an increment in the charge transfer resistance. The limit of detection, based on impedance spectroscopy, is 100 aM for both H3 NF and H3 NS hybrids, with the H3 NF hybrid biosensor having better analytical performance in terms of linearity, selectivity, repeatability, and stability., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Genosensor-based electrodes mediated with nanoparticles (NPs) have tremendously developed in medical diagnosis. Herein, we report a facile, rapid, low cost and highly sensitive biosensing strategy for early detection of HPV 18 using gold-nanoparticles (AuNPs) deposited on micro-IDEs. This study represents surface charge transduction of micro-interdigitated electrodes (micro-IDE) alumina insulated with silica, independent and mini genosensor modified with colloidal gold NPs (AuNPs), and determination of gene hybridization for early detection of cervical cancer. The surface of AuNPs deposited micro-IDE functionalized with optimized 3-aminopropyl-triethoxysilane (APTES) followed by hybridization with deoxyribonucleic acid (DNA) virus to develop DNA genosensor. The results of ssDNA hybridization with the ssDNA target of human papillomavirus (HPV) 18 have affirmed that micro-IDE functionalized with colloidal AuNPs resulted in the lowest detection at 0.529 aM. Based on coefficient regression, micro-IDE functionalized with AuNPs produces better results in the sensitivity test (R 2  = 0.99793) than unfunctionalized micro-IDE., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: NOR AZIZAH BINTI PARMIN reports financial support was provided by Ministry of Higher Education, Malaysia. NOR AZIZAH BINTI PARMIN reports a relationship with University Malaysia Perlis that includes: employment, non-financial support, and speaking and lecture fees. NOR AZIZAH BINTI PARMIN has patent # LY2021P00579 pending to NOR AZIZAH BINTI PARMIN. The authors declare that they have no known competing financial interests or personal relationships that could have influenced the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Dicranopteris linearis (DL) is a fern in the Gleicheniaceae family, locally known as resam by the Malay community. It has numerous pharmacological benefits, with antiulcer and gastroprotective properties. Peptic ulcer is a chronic and recurring disease that significantly impacts morbidity and mortality, affecting nearly 20 % of the world's population. Despite the effectiveness of peptic ulcer drugs, there is no perfect treatment for the ailment. Encapsulation is an advanced technique that can treat peptic ulcers by incorporating natural sources. This work aims to encapsulate DL extract using different types of cellulose particles by the solvent displacement technique for peptic ulcer medication. The extract was encapsulated using methyl cellulose (MC), ethyl cellulose (EC), and a blend of ethyl methyl cellulose through a dialysis cellulose membrane tube and freeze-dried to yield a suspension of the encapsulated DL extracts. The microencapsulated methyl cellulose chloroform extract (MCCH) has a considerably greater level of total phenolic (84.53 ± 6.44 mg GAE/g), total flavonoid (84.53 ± 0.54 mg GAE/g), and antioxidant activity (86.40 ± 0.63 %). MCCH has the highest percentage of antimicrobial activity against Escherichia coli (2.42 ± 10 7  × 0.70 CFU/mL), Bacillus subtilis (5.21 ± 10 7  × 0.90 CFU/mL), and Shigella flexneri (1.25 ± 10 7  × 0.66 CFU/mL), as well as the highest urease inhibitory activity (50.0 ± 0.21 %). The MCCH particle size was estimated to be 3.347 ± 0.078 μm in diameter. It has been proven that DL elements were successfully encapsulated in the methyl cellulose polymer in the presence of calcium (Ca). Fourier transform infrared (FTIR) analysis indicated significant results, where the peak belonging to the CO stretch of the carbonyl groups of methyl cellulose (MC) shifted from 1638.46 cm -1 in the spectrum of pure MC to 1639.10 cm -1 in the spectrum of the MCCH extract. The shift in the wavenumbers was due to the interactions between the phytochemicals in the chloroform extract and the MC matrix in the microcapsules. Dissolution studies in simulated gastric fluid (SGF) and model fitting of encapsulated chloroform extracts showed that MCCH has the highest EC 50 of 6.73 ± 0.27 mg/mL with R 2  = 0.971 fitted by the Korsmeyer-Peppas model, indicating diffusion as the mechanism of release., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Sodium alginate/hydroxyapatite/Nano cellulose (SA/HA/NC) nanocomposite films that possess good biocompatibility for bone tissue engineering are prepared by a simple solution casting. HA is one of the most frequently used bioceramic materials to achieve a high biocompatibility. The bionanocomposite films are analysed by XRD, SEM, EDAX and FTIR studies. XRD confirms the existence of fillers in the polymer. FTIR spectrum shows the different functional modes in the bionanocomposite films. The morphology of fillers and bionanocomposite films are obtained through SEM. The inclusion of NC with different concentrations into the biopolymer film improves the tensile strength. As a result, the loading of 5 wt % of NC and 10 wt% of HA in the SA polymer shows high tensile strength when compared to the pure SA, SA filled with 10 wt% of HA and SA loaded with 10 wt% of HA and inclusion of NC (0.5 and 2.5 wt%). The tensile strength (TS) of bionanocomposite film with 10 wt % of HA is increased by 17%. TS of bionanocomposite film with 0.5 and 2.5 wt% of NC is increased by 177 and 277%, whereas TS of bionanocomposite film loaded 5 wt% of NC is increased by 331%. The swelling, biodegradation and biomineralization tests suggest that this bionanocomposite films are hopeful biomaterials for bone tissue engineering., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Anticoagulant therapies are crucial in the management of surgical complications as well as the prophylaxis of thrombosis. Many studies are being conducted on the Habu snake-venom anticoagulant, FIX-binding protein (FIX-Bp), for its greater potency and strong affinity to FIX clotting factor. On the other hand, the capacity to promptly reverse such acute anticoagulation is equally important. Combining a reversible anticoagulant with FIX-Bp may be advantageous in maintaining the balance between adequate anticoagulation and repealing when necessary. In this study, authors integrated FIX-Bp and RNA aptamer-based anticoagulants into a single target, FIX clotting factor, in order to achieve a robust anticoagulant effect. An in-silico and electrochemical approach were used to investigate the combination of FIX-Bp and RNA aptamers as a bivalent anticoagulant and to verify the competing or predominant binding sites of each anticoagulant. The in-silico analysis discovered that both the venom- and aptamer-anticoagulant had a strong affinity for the FIX protein at the Gla-domain and EGF-1 domain by holding 9 conventional hydrogen bonds with the binding energy of -34.859 kcal/mol. The electrochemical technique verified that both anticoagulants had different binding sites. The impedance load upon RNA aptamer binding to FIX protein was 14 %, whereas the addition of FIX-Bp caused a significant impedance rise of 37 %. This indicates that the addition of aptamers prior to FIX-Bp is a promising strategy for the conception of a hybrid anticoagulant., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Misfolding and accumulation of the protein alpha synuclein in the brain cells characterize Parkinson's disease (PD). Electrochemical based aluminum interdigitated electrodes (ALIDEs) was fabricated by using conventional photolithography method and modified the surfaces with zinc oxide and gold nanorod by using spin coating method for the analysis of PD protein biomarker. The device surface modified with gold nanorod of 25 nm diameter was used. The bare devices and the surface modified devices were characterized by Scanning Electron Microscope, 3D-Profilometer, Atomic Force Microscope and high-power microscope. The above measurement was also performed to measure the interaction of antibody with aggregated alpha-synuclein for normal, aggregated and aggregated alpha synuclein in human serum and distinguished against 3 control proteins (PARK1, DJ-1 and Factor IX). The detection limit for normal alpha synuclein was 1 f. with the sensitivity of 1 f. on a linear regression (R 2  = 0.9759). The detection limit for aggregated alpha synuclein was 10 aM with the sensitivity of 1 aM on a linear regression (R 2  = 0.9797). Also, the detection limit of aggregated alpha synuclein in serum was 10 aM with the sensitivity of 1 aM on a linear regression (R 2  = 0.9739). These results however indicate that, serum has only minimal amount of alpha synuclein., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Highly sensitive and easy detection method for Alzheimer's disease (AD) with a suitable biomarker is mandatory for preventing the factors resulting from AD. This research reports a modified ELISA with graphene for the detection of AD biomarker amyloid beta (Aβ) oligomer. Gold nanoparticle (AuNP) conjugated aptamer was used as the capture probe and attached on ELISA-graphene oxide surface through the amine linker. Antibody was used as the detection molecule to reach the maximum detection of Aβ oligomer. Suitable level of APTMS (2%), size of AuNP (30 nm) and aptamer concentration (2 μM) were optimized. This sandwich pattern of aptamer-Aβ oligomer-antibody helps to reach the detection at 50 pM on the optimized ELISA surface and the control experiments in the absence of Aβ oligomer or anti-Aβ oligomer antibody did not show the significant optical detection at 492 nm, indicting the specific detection. Further, Aβ oligomer spiked artificial cerebrospinal fluid did not interfere the detection of Aβ oligomer, confirming the selective detection. This new and modified ELISA surface helps to reach the lower detection of Aβ oligomer and diagnose AD., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This work explores Electrochemical Impedance Spectroscopy (EIS) detection for a highly-sensitive quantification of prostate-specific antigen (PSA) in Faradaic (f-EIS) and non-Faradaic modes (nf-EIS). Immobilization of monoclonal antibody specific to PSA (anti-PSA) was performed using 1-ethyl-3-dimethylaminopropylcarbodiimide hydrochloride and N-hydroxysuccinimide crosslinking agents in order to conjugate carboxylic (-COOH) terminated group of 16-Mercaptoundecanoic acid with amine (-NH 3 + ) on anti-PSA epitope. This approach offers simple and efficient approach to form a strong, covalently bound thiol-gold (SAu) for a reliable SAM layer formation. Studies on the topographic of pristine Au-IDE surface were performed by Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy techniques, meanwhile a 3-dimensional optical surface profiler, Atomic Force Microscopy and X-ray Photoelectron Spectroscopy techniques were used to validate the successful functionalization steps on the sensor transducer surface. Detection of PSA in f-EIS mode was carried out by measuring the response in charge transfer resistance (R ct ) and impedance change (Z), meanwhile in nf-EIS mode, the changes in device capacitance was monitored. In f-EIS mode, the sensor reveals a logarithmic detection of PSA in a range of 100 ng/ml down to 0.01 ng/ml in Phosphate Buffered Saline with a recorded sensitivity of 2.412 kΩ/log 10 ([PSA] ng/ml) and the limit of detection (LOD) down to 0.01 ng/ml. The nf-EIS detection mode yields a logarithmic detection range of 5000 ng/ml down to 0.5 ng/ml, with a sensitivity of 8.570 nF/log 10 ([PSA] ng/ml) and an LOD of 0.5 ng/ml. The developed bio-assay yields great device stability, specificity to PSA and repeatability of detection that would pave its way for the future development into portable lab-on-chip bio-sensing system., (Copyright © 2020. Published by Elsevier B.V.)

Haemophilia is a blood clotting disorder known as 'Christmas disease' caused when the blood has defect with the clotting factor(s). Bleeding leads various issues, such as chronic pain, arthritis and a serious complication during the surgery. Identifying this disease is mandatory to take the necessary treatment and maintains the normal clotting. It has been proved that the level of factor IX (FIX) is lesser with haemophilia patient and the attempt here is focused to quantify FIX level by interdigitated electrode (IDE) sensor. Single-walled carbon nanotube (SWCNT) was utilized to modify IDE sensing surface. On this surface, dual probing was evaluated with aptamer and antibody to bring the possible advantages. The detection limit with antibody was found to be 1 pM, while aptamer shows 100 fM. Further, a fine-tuning was attempted with sandwich pattern of aptamer-FIX-antibody and antibody-FIX-aptamer and compared. Specific elevation of detection with 10 folds was noticed and displayed the detection at 100 f. in both sandwich patterns. In addition, FIX was detected in the diluted human serum by aptamer-FIX-antibody sandwich, it was found that FIX detected from the dilution factor 1:640. A novel demonstration is with higher discrimination against other clotting factors, XI and VII., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest regarding the publication of this paper., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Activated pancreatic stellate cells (PSCs) have been widely accepted as a key precursor of excessive pancreatic fibrosis, which is a crucial hallmark of chronic pancreatitis (CP) and its formidable associated disease, pancreatic cancer (PC). Hence, anti-fibrotic therapy has been identified as a novel therapeutic strategy for treating CP and PC by targeting PSCs. Most of the anti-fibrotic agents have been limited to phase I/II clinical trials involving vitamin analogs, which are abundant in medicinal plants and have proved to be promising for clinical application. The use of phytomedicines, as new anti-fibrotic agents, has been applied to a variety of complementary and alternative approaches. The aim of this review was to present a focused update on the selective new potential anti-fibrotic agents, including curcumin, resveratrol, rhein, emodin, green tea catechin derivatives, metformin, eruberin A, and ellagic acid, in combating PSC in CP and PC models. It aimed to describe the mechanism(s) of the phytochemicals used, either alone or in combination, and the associated molecular targets. Most of them were tested in PC models with similar mechanism of actions, and curcumin was tested intensively. Future research may explore the issues of bioavailability, drug design, and nano-formulation, in order to achieve successful clinical outcomes with promising activity and tolerability., (© 2020 Chinese Pharmaceutical Association and Institute of Materia Medica, Chinese Academy of Medical Sciences. Production and hosting by Elsevier B.V.)

α-synuclein is a predominantly expressing neuronal protein for understanding the neurodegenerative disorders. A diagnosing system with aggregated α-synuclein encoded by SNCA gene is necessary to make the precautionary treatment against Parkinson's disease (PD). Herein, gold-nanourchin conjugated anti-α-synuclein antibody was desired as the probe and seeded on single-walled carbon nanotube (SWCN) integrated interdigitated electrode (IDE). The surface morphology of SWCN-modified IDE and gold urchin-antibody conjugates were observed under FESEM, FETEM and AFM, the existing elements were confirmed. Voltammetry analysis revealed that the limit of fibril-formed α-synuclein detection was improved by 1000 folds (1 fM) with gold-nanourchin-antibody modified surface, compared to the surface with only antibody (1 pM). Validating the interaction of α-synuclein by Enzyme-linked Immunosorbent Assay was displayed the detection limit as 10 pM. IDE has a good reproducibility and a higher selectivity on α-synuclein as evidenced by the interactive analysis with the control proteins, PARK1 and DJ-1., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Human papilloma virus (HPV) affects predominantly the genital area, which includes vagina, cervix, penis, vulva scrotum, rectum and anus. Among 100 types of HPV, 14 types are considered to cause the risky cancer. The gene HPV-16 E7 is responsible for the development of cancer with the infected women. Earlier identification of this gene sequence avoids the cancer progression. The targeted HPV-16 E7 sequence was sandwiched by capture and reporter sequences on the carbodiimidazole-modified interdigitated electrode (IDE) surface. Target sequence at 100 f. was paired to the capture sequence immobilized on IDE sensing surface. To this surface, different concentrations of reporter sequence with and without gold rod (GNR) were evaluated. In both cases the detections were attained 1 aM by the reporter sequence pairing and with GNR increments in current were found. This enhancement was found to be 1000 folds, considering the condition was revealed in the absence of reporter. This sandwich detection strategy of capture-target-reporter sequences for HPV-16 detection on the IDE sensing surface helps to diagnose the association of cervical cancer., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Human papillomavirus (HPV) is a double-standard DNA virus, as well as the source of infection to the mucous membrane. It is a sexually transmitted disease that brings the changes in the cervix cells. Oncogenes, E6 and E7 play a pivotal role in the HPV infection. Identifying these genes to detect HPV strains, especially a prevalent HPV16 strain, will bring a great impact. Among different sensing strategies for pathogens, the dielectric electrochemical biosensor shows the potential due to its higher sensitivity. In this research, HPV16-E7 DNA sequence was detected on the carbodiimidazole-modified interdigitated electrode (IDE) surface with the detection limit of 1 fM. To enhance the sensitivity, the target sequence was conjugated on gold nanoparticle (GNP) and attained detection to the level of 10 aM. This produced ~100 folds improvement in detecting HPV16-E7 gene and 4 folds increment in the current flow. The stability of HPV16-E7 DNA sequences on GNP was verified by the salt-induced GNP aggregation. The current system has shown the higher specificity by comparing against non-complementary and triple-mismatched DNA sequences of HPV16-E7. This demonstration in detecting HPV16-E7 using dielectric IDE sensing system with a higher sensitivity can be recommended for detecting a wide range of disease-causing DNA-markers., (Copyright © 2019. Published by Elsevier B.V.)

A report on the de novo Whole Genome Sequence (WGS) of Marinobacter litoralis SW-45, a moderately salt-tolerant bacterium isolated from the seawater in Malaysia is presented. The strain has a genome size of 3.45 Mb and is capable of producing halophilic lipase, protease and esterase enzymes. Computational prediction of non-coding RNA (ncRNA) genes in M. litoralis SW-45 was performed using standalone software known as the non-coding RNA characterization (nocoRNAc). In addition, a phylogenetic tree showing the evolutionary relationship between the strain and other members of the genus Marinobacter was constructed using 16SrRNA sequence information. A total of 385 ncRNA transcripts, 1124 terminator region, and 2350 Stress Induced Duplex Destabilization sites were predicted. The current WGS shotgun project has provided the relevant genetic information that may be useful for the strain's improvement studies. This manuscript gives the first description of M. litoralis with a complete genome., (Copyright © 2019. Published by Elsevier B.V.)

Prognosis of early cancer detection becomes one of the tremendous issues in the medical health system. Medical debates among specialist doctor and researcher in therapeutic approaches became a hot concern for cervix cancer deficiencies early screening, risk factors cross-reaction, portability device, rapid and free labeling system. The electrical biosensing based system showed credibility in higher specificity and selectivity due to hybridization of DNA duplex between analyte target and DNA probes. Electrical DNA sensor for cervix cancer has attracted too many attentions to researcher notification based on high performance, easy to handle, rapid system and possible to miniaturize. This review explores the current progression and future insignificant for HPV E6 genobiosensing for early Detection Strategies of Cervical Cancer., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Interaction between split RNA aptamer and the clinically important target, HIV-1 Tat was investigated on a biosensing surface transduced by functionally choreographed multiwall carbon nanotubes (MWCNTs). Acid oxidation was performed to functionalize MWCNTs with carboxyl functional groups. X-ray photoelectron spectroscopy analysis had profound ~2.91% increment in overall oxygen group and ~1% increment was noticed with a specific carboxyl content owing to CO and OCO bonding. The interaction between split RNA aptamer and HIV-1 Tat protein was quantified by electrical measurements with the current signal (I ds ) over a gate voltage (V gs ). Initially, 34.4 mV gate voltage shift was observed by the immobilization of aptamer on MWCNT. With aptamer and HIV-1 Tat interaction, the current flow was decreased with the concomitant gate voltage shift of 23.5 mV. The attainment of sensitivity with split aptamer and HIV-1 Tat interaction on the fabricated device was 600 pM. To ensure the genuine interaction of aptamer with HIV-1 Tat, other HIV-1 proteins, Nef and p24 were interacted with aptamer and they displayed the negligible interferences with gate voltage shift of 3.5 mV and 5.7 mV, which shows 4 and 2.5 folds lesser than HIV-1 Tat interaction, respectively., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Reduction of graphene oxide becomes an alternative way to produce a scalable graphene and the resulting nanomaterial namely reduced graphene oxide (rGO) has been utilized in a wide range of potential applications. In this article, the level of green reduction strategies, especially the solution-based reduction methods are overviewed based on recent progression, to get insights towards biomedical applications. The degrees of gaining tips with the solution-based green reduction methods, conditions, complexity and the resulting rGO characteristics have been elucidated comparatively. Moreover, the application of greenly produced rGO in electrochemical biosensors has been elucidated as well as their electrical performance in term of linear range and limit of detections for various healthcare biological analytes. In addition, the characterization scheme for graphene-based materials and the analyses on the reduction especially for the solution-based green reduction methods are outlined for the future endeavours., (Copyright © 2018 Elsevier B.V. All rights reserved.)

There are different clotting factors present in blood, carries the clotting cascade and excessive bleeding may cause a deficiency in the clotting Diagnosis of this deficiency in clotting drastically reduces the potential fatality. For enabling a sensor to detect the clotting factors, suitable probes such as antibody and aptamer have been used to capture these targets on the sensing surface. Two major clotting factors were widely studied for the diagnosis of clotting deficiency, which includes factor IX and thrombin. In addition, factor IX is considered as the substitute for heparin and the prothrombotic associated with the increased thrombin generation are taking into account their prevalence. The biosensors, surface plasmon resonance, evanescent-field-coupled waveguide-mode sensor, metal-enhanced PicoGreen fluorescence and electrochemical aptasensor were well-documented and improvements have been made for high-performance sensing. We overviewed detecting factor IX and thrombin using these biosensors, for the potential application in medical diagnosis., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Nanocellulose prepared from the natural material has a promising wide range of opportunities to obtain the superior material properties towards various end-products. In this research, commercially available natural cotton was treated with aqueous sodium hydroxide solution to eliminate the hemicellulose and lignin, then cellulose was collected. The collected cellulose was subjected to acid hydrolysis using sulfuric acid to obtain nanocellulose. The prepared nanocellulose was further characterized with the aid of Fourier transform infrared spectroscopy, X-ray diffraction and Scanning Electron Microscopy to elucidate the chemical structure, crystallinity and the morphology., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Human Papillomavirus (HPV) is a standout amongst the most commonly reported over 100 types, among them genotypes 16, 18, 31 and 45 are the high-risk HPV. Herein, we designed the oligonucleotide probe for the detection of predominant HPV type 16 for the sensing applications. Conserved amino acid sequences within E6 region of the open reading frame in the HPV genome was used as the basis to design oligonucleotide probe to detect cervical cancer. Analyses of E6 amino acid sequences from the high-risk HPVs were done to check the percentage of similarity and consensus regions that cause different cancers, including cervical cancer. Basic local alignment search tools (BLAST) have given extra statistical parameters, for example, desire values (E-values) and score bits. The probe, 'GGG GTC GGT GGA CCG GTC GAT GTA' was designed with 66.7% GC content. This oligonucleotide probe is designed with the length of 24 mer, GC percent is between 40 and 70, and the melting point (Tm) is above 50°C. The probe needed an acceptable length between 22 and 31 mer. The choice of region is identified here can be used as a probe, has implications for HPV detection techniques in biosensor especially for clinical determination of cervical cancer., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Enzyme Linked Immunosorbent Assay (ELISA) is a standard assay that has been used widely to validate the presence of analyte in the solution. With the advancement of ELISA, different strategies have shown and became a suitable immunoassay for a wide range of analytes. Herein, we attempted to provide additional evidence with ELISA, to show its suitability for multi-analyte detection. To demonstrate, three clinically relevant targets have been chosen, which include 16kDa protein from Mycobacterium tuberculosis, human blood clotting Factor IXa and a tumour marker Squamous Cell Carcinoma antigen. Indeed, we adapted the routine steps from the conventional ELISA to validate the occurrence of analytes both in homogeneous and heterogeneous solutions. With the homogeneous and heterogeneous solutions, we could attain the sensitivity of 2, 8 and 1nM for the targets 16kDa protein, FIXa and SSC antigen, respectively. Further, the specific multi-analyte validations were evidenced with the similar sensitivities in the presence of human serum. ELISA assay in this study has proven its applicability for the genuine multiple target validation in the heterogeneous solution, can be followed for other target validations., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Nanoparticles have been investigated as flagging tests for the sensitive DNA recognition that can be utilized as a part of field applications to defeat restrictions. Gold nanoparticles (AuNPs) have been widely utilized due to its optical property and capacity to get functionalized with a mixed bag of biomolecules. This study exhibits the utilization of AuNPs functionalized with single-stranded oligonucleotide (AuNP-oligo test) for fast the identification of Human Papillomavirus (HPV). This test is displayed on interdigitated electrode sensor and supported by colorimetric assay. DNA conjugated AuNP has optical property that can be controlled for the applications in diagnostics. With its identification abilities, this methodology incorporates minimal effort, strong reagents and basic identification of HPV., (Copyright © 2016 Elsevier B.V. All rights reserved.)

A real-time ability to interpret the interaction between targeted biomolecules and the surface of semiconductors (metal transducers) into readable electrical signals, without biomolecular modification involving fluorescence dyes, redox enzymes, and radioactive labels, created by label-free biosensors has been extensively researched. Field-effect transistor (FET)- and capacitor-based biosensors are among the diverse electrical charge biosensing architectures that have drawn much attention for having charge transduction; thus, enabling the early and rapid diagnosis of the appropriate cardiac biomarkers at lower concentrations. These semiconducting material-based transducers are very suitable to be integrated with portable electronic devices for future online collection, transmission, reception, analysis, and reporting. This overview elucidates and clarifies two major electrical label-free systems (FET- and capacitor-based biosensors) with cardiac troponin (cTn) biomarker-mediated charge transduction for acute myocardial infarction (AMI) diagnosis. Advances in these systems are highlighted by their progression in bridging the laboratory and industry; the foremost technologies have made the transition from benchtop to bedside and beyond., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Diabetes is a metabolic disease with a prolonged elevated level of glucose in the blood leads to long-term complications and increases the chances for cardiovascular diseases. The present study describes the fabrication of a ZnO nanowire (NW)-modified interdigitated electrode (IDE) to monitor the level of blood glucose. A silver IDE was generated by wet etching-assisted conventional lithography, with a gap between adjacent electrodes of 98.80 μm. The ZnO-based thin films and NWs were amended by sol-gel and hydrothermal routes. High-quality crystalline and c-axis orientated ZnO thin films were observed by XRD analyses. The ZnO thin film was annealed for 1, 3 and 5 h, yielding a good-quality crystallite with sizes of 50, 100 and 110 nm, and the band gaps were measured as 3.26, 3.20 and 3.17 eV, respectively. Furthermore, a flower-modeled NW was obtained with the lowest diameter of 21 nm. Our designed ZnO NW-modified IDE was shown to have a detection limit as low as 0.03 mg/dL (correlation coefficient = 0.98952) of glucose with a low response time of 3 s, perform better than commercial glucose meter, suitable to instantly monitor the glucose level of diabetes patients. This study demonstrated the high performance of NW-mediated IDEs for glucose sensing as alternative to current glucose sensors., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Field-effect transistors (FETs) have succeeded in modern electronics in an era of computers and hand-held applications. Currently, considerable attention has been paid to direct electrical measurements, which work by monitoring changes in intrinsic electrical properties. Further, FET-based sensing systems drastically reduce cost, are compatible with CMOS technology, and ease down-stream applications. Current technologies for sensing applications rely on time-consuming strategies and processes and can only be performed under recommended conditions. To overcome these obstacles, an overview is presented here in which we specifically focus on high-performance FET-based sensor integration with nano-sized materials, which requires understanding the interaction of surface materials with the surrounding environment. Therefore, we present strategies, material depositions, device structures and other characteristics involved in FET-based devices. Special attention was given to silicon and polyaniline nanowires and graphene, which have attracted much interest due to their remarkable properties in sensing applications., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Label-free-based detection is pivotal for real-time monitoring of biomolecular interactions and to eliminate the need for labeling with tags that can occupy important binding sites of biomolecules. One simplest form of label-free-based detection is ultraviolet-visible-near-infrared (UV-vis-NIR) spectroscopy, which measure changes in reflectivity as a means to monitor immobilization and interaction of biomolecules with their corresponding partners. In biosensor development, the platform used for the biomolecular interaction should be suitable for different molecular recognition elements. In this study, gold (Au)-coated polycarbonate was used as a platform and as a proof-of-concept, erythropoietin (EPO), a doping substance widely abused by the athletes was used as the target. The interaction of EPO with its corresponding molecular recognition elements (anti-EPO monoclonal antibody and anti-EPO DNA aptamer) is monitored by UV-vis-NIR spectroscopy. Prior to this, to show that UV-vis-NIR spectroscopy is a suitable method for measuring biomolecular interaction, the interaction between biotin and streptavidin was demonstrated via this strategy and reflectivity of this interaction decreased by 25%. Subsequent to this, interaction of the EPO with anti-EPO monoclonal antibody and anti-EPO DNA aptamer resulted in the decrease of reflectivity by 5% and 10%, respectively. The results indicated that Au-coated polycarbonate could be an ideal biosensor platform for monitoring biomolecular interactions using UV-vis-NIR spectroscopy. A smaller version of the Au-coated polycarbonate substrates can be derived from the recent set-up, to be applied towards detecting EPO abuse among atheletes., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Influenza virus hemagglutinin (HA) mediates both receptor (glycan) binding and membrane fusion for cell entry and has been the basis for typing influenza A viruses. In this study we have selected RNA aptamers (D-12 and D-26) that specifically target the HA protein of the recent pandemic influenza virus pdmH1N1 (A/California/07/2009). Among the selected aptamers the D-26 aptamer showed higher affinity for the HA of pdmH1N1 and was able to distinguish HA derived from other sub-types of influenza A viruses. The affinity of the D-26 aptamer was further improved upon incorporation of 2'-fluoropyrimidines to a level of 67 fM. Furthermore, the high affinity D-12 and D-26 aptamers were tested for their ability to interfere with HA-glycan interactions using a chicken red blood cell (RBC) agglutination assay. At a concentration of 200 nM the D-26 aptamer completely abolished the agglutination of RBCs, whereas D-12 only did so at 400 nM. These studies suggest that the selected aptamer D-26 not only has a higher affinity and specificity for the HA of pdmH1N1 but also has a better ability to efficiently interfere with HA-glycan interactions compared with the D-12 aptamer. The D-26 aptamer warrants further study regarding its application in developing topical virucidal products against the pdmH1N1 virus and also in surveillance of the pdmH1N1 influenza virus., (Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

An evanescent-field-coupled waveguide-mode sensor of the Kretschmann configuration with a silica waveguide having nanoscale holes is an ideal tool for detection of bimolecular reactions. In the present research, an optimized surface of the sensor with cylindrical nanoscale holes was modified with sodium (1-{[6-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)hexanoyl]oxy}-2,5-dioxopyrrolidine-3-sulfonate) (Sulfo-EMCS) to facilitate the attachment of biomolecules; the resulting surface could be cleaned for reuse simply by changing the pH of the buffering solution. The modification is expected to be useful for wide range of molecular detection., (Copyright © 2010 Elsevier B.V. All rights reserved.)