The use of a PtAu catalyst as an anode catalyst for the oxidation of formic acid in direct formic acid fuel cells is described. Catalytic activities of PtAu and PtRu anodes were studied using a linear sweep voltammetry technique in a single cell configuration. PtAu showed a lower on-set potential and a larger current density than that of PtRu in formic acid oxidation. In addition, the maximum power densities at 30 ◦ C for PtAu and PtRu were 94 and 74 mW cm −2 , respectively. In order to evaluate long-term durability, the single cells were operated for hundreds of hours with a 6 M aqueous formic acid solution at 60 ◦ C under 100 mA cm −2 . The difference in performance between PtAu and PtRu after 500 h reached ca.

Short communication Electro-oxidation of methanol and formic acid on PtRu and PtAu for direct liquid fuel cells

Electrochemical Sensors and Biosensors Based on Graphene Functionalized with Metal Oxide Nanostructures for Healthcare Applications

Since the ferromagnetic (Fe3O4) nanoparticles were firstly reported to exert enzyme-like activity in 2007, extensive research progress in nanozymes has been made with deep investigation of diverse nanozymes and rapid development of related nanotechnologies. As promising alternatives for natural enzymes, nanozymes have broadened the way toward clinical medicine, food safety, environmental monitoring, and chemical production. The past decade has witnessed the rapid development of metal- and metal oxide-based nanozymes owing to their remarkable physicochemical properties in parallel with low cost, high stability, and easy storage. It is widely known that the deep study of catalytic activities and mechanism sheds significant influence on the applications of nanozymes. This review digs into the characteristics and intrinsic properties of metal- and metal oxide-based nanozymes, especially emphasizing their catalytic mechanism and recent applications in biological analysis, relieving inflammation, antibacterial, and cancer therapy. We also conclude the present challenges and provide insights into the future research of nanozymes constituted of metal and metal oxide nanomaterials.

/pdf/a-review-on-metal-and-metal-oxide-based-nanozymes-properties-42jd6wb2mo.pdf

A Review on Metal- and Metal Oxide-Based Nanozymes: Properties, Mechanisms, and Applications

Recent advances and remaining challenges for polymeric nanocomposites in healthcare applications

Hemoglobin A1C (HbA1c) is used as an index of average blood glucose measurement over a period of months and is a mainstay of blood glucose monitoring. This metric is easy to measure and relatively inexpensive to obtain, and it predicts diabetes-related microvascular complications. However, HbA1c provides only an approximate measure of glucose control; it does not address short-term glycemic variability (GV) or hypoglycemic events. Continuous glucose monitoring (CGM) is a tool which helps clinicians and people with diabetes to overcome the limitations of HbA1c in diabetes management. Time spent in the glycemic target range and time spent in hypoglycemia are the main CGM metrics that provide a more personalized approach to diabetes management. Moreover, the glucose management indicator (GMI), which calculates an approximate HbA1c level based on the average CGM-driven glucose level, facilitates individual decision-making when the laboratory-measured HbA1c and estimated HbA1c are discordant. GV, on the other hand, is a measure of swings in blood glucose levels over hours or days and may contribute to diabetes-related complications. In addition, addressing GV is a major challenge during the optimization of glycemia. The degree of GV is associated with the frequency, duration, and severity of the hypoglycemic events. Many factors affect GV in a patient, including lifestyle, diet, the presence of comorbidities, and diabetes therapy. Recent evidence supports the use of some glucose-lowering agents to improve GV, such as the new ultra-long acting insulin analogs, as these agents have a smoother pharmacodynamic profile and improve glycemic control with fewer fluctuations and fewer nocturnal hypoglycemic events. These newer glucose-lowering agents (such as incretin hormones or sodium–glucose cotransporter 2 inhibitors) can also reduce the degree of GV. However, randomized trials are needed to evaluate the effect of GV on important diabetes outcomes. In this review, we discuss the role of HbA1c as a measure of glycemic control and its limitations. We also explore additional glycemic metrics, with a focus on time (duration) in glucose target range, time (duration) in hypoglycemia, GV, GMI, and their correlation with clinical outcomes.

/pdf/a-view-beyond-hba1c-role-of-continuous-glucose-monitoring-4riqsvo32j.pdf

A View Beyond HbA1c: Role of Continuous Glucose Monitoring.

The percentage of glycosylated hemoglobin A1c (% HbA1c) in human whole blood indicates the average plasma glucose concentration over a prolonged period of time and is used to diagnose diabetes. Currently, common laboratory methods to recognize glycated proteins are high-performance liquid chromatography, immunoassay and electrophoresis. The accuracy and the precision of A1c assays at least match those of glucose assays. Consequently, American Diabetes Association, the European Association for the Study of Diabetes and the International Diabetes Federation decided that the A1c assay should be recognized as the primary method for diagnosing diabetes. The recent availability of rapid, reliable, and easy-to-perform tests for detecting HbA1c has introduced rapid Diabetes diagnosis. This review thus summarizes the current information on the present and future aspects of diagnostic methods for HbA1c.

/pdf/laboratory-diagnosis-of-hba1c-a-review-uduojtymdl.pdf

Laboratory Diagnosis of HbA1c: A Review

Helicobacter pylori is a Gram-negative, spiral shaped, microaerophilic bacteria that colonizes human gastric mucosa and causes various gastric diseases. In this work, the utilization of ion irradiated zinc oxide tetrapods (ZnO-T) based biohybrid interface accentuates the development of an electrochemical immunosensor for the fast and sensitive detection of H. pylori. After coating of (ZnO-T) over the surface of screen printed electrode (SP-AuE) through electrodeposition, the ZnO-T/SP-AuE was irradiated with N2+ ion of energy 100 keV. The ion irradiation significantly enhances the conductivity of ZnO-T coated SP-AuE. The revamped SP-AuE is further used for establishing an immunosensor interface based upon immobilization of the CagA antigen on ZnO-T electrodeposited over the surface of SP-AuE. The sensing interface demonstrated good linearity (0.2 ng/mL to 50 ng/mL) and limit of detection (0.2 ng/mL). The ion beam irradiated ZnO-T based immunosensor showed significantly high conductivity and enhanced the analytical properties of the working electrode in terms of the sensitivity, detection limit, and response time. A study on the comparison of irradiated and pristine electrode is performed for amperometric sensing of H. pylori. In addition, the significance of work conducted on ion irradiated ZnO-T based interfaces provides a basis of further development of electrochemical immunosensors.

Zinc Oxide Tetrapods Based Biohybrid Interface for Voltammetric Sensing of Helicobacter pylori.

The gastric colonization of human hosts by Helicobacter pylori (H. pylori) increases the risk of developing gastritis, ulcers and gastric cancer. To detect H. pylori, a nanohybrid-based BabA immunosensor is developed herein. BabA is an outer membrane protein and one of the major virulence factors of H. pylori. To design the immunosensor, an Au electrode is loaded with palladium nanoparticles (Pdnano) by electrodeposition to generate reduced graphene oxide (rGO)/poly(3,4-ethylenedioxythiophene) (PEDOT). The immobilization of these nanostructured materials imparts a large surface area and electroconductivity to bio-immune-sensing molecules (here, the BabA antigen and antibodies). After optimization, the fabricated immunosensor has the ability to detect antigens (H. pylori) in a linear range from 0.2 to 20 ng/mL with a low LOD (0.2 ng/mL). The developed immunosensor is highly specific, sensitive and reproducible. Additionally, in silico methods were employed to better understand the hybrid nanomaterials of the fabricated Pdnano/rGO/PEDOT/Au electrode. Simulations performed by molecular docking, and Metropolis Monte Carlo adsorption studies were conducted. The results revealed that the hybrid nanomaterials exhibit a stable antigen-antibody complex of BabA, yielding the lowest binding energy in relation to the electrode materials, emphasizing the functionality of the constructed electrodes in the electrochemical immunosensor.

/pdf/nanohybrid-based-immunosensor-prepared-for-helicobacter-520kvs265p.pdf

Nanohybrid-based immunosensor prepared for Helicobacter pylori BabA antigen detection through immobilized antibody assembly with @ Pdnano/rGO/PEDOT sensing platform.

Detection of glycated hemoglobin with voltammetric sensing amplified by 3D-structured nanocomposites

Construction of an amperometric glycated hemoglobin biosensor based on Au-Pt bimetallic nanoparticles and poly (indole-5-carboxylic acid) modified Au electrode.

Shaivya Gupta

Papers

Laboratory Diagnosis of HbA1c: A Review

Zinc Oxide Tetrapods Based Biohybrid Interface for Voltammetric Sensing of Helicobacter pylori.

Nanohybrid-based immunosensor prepared for Helicobacter pylori BabA antigen detection through immobilized antibody assembly with @ Pdnano/rGO/PEDOT sensing platform.

Detection of glycated hemoglobin with voltammetric sensing amplified by 3D-structured nanocomposites

Construction of an amperometric glycated hemoglobin biosensor based on Au-Pt bimetallic nanoparticles and poly (indole-5-carboxylic acid) modified Au electrode.