Noninvasive Monitoring of Glycemia Level in Diabetic Patients by Wearable Advanced Biosensors.

We report on the possibility of noninvasive diabetes monitoring through continuous analysis of sweat. The prediction of the blood glucose level in diabetic patients is possible on the basis of their sweat glucose content due to the positive correlation discovered. The ratio between the blood glucose and sweat glucose concentrations for a certain diabetic subject is stable within weeks, excluding requirements for frequent blood probing.

Novel Siloxane Derivatives as Membrane Precursors for Lactate Oxidase Immobilization.

We report new enzyme-containing siloxane membranes for biosensor elaboration. Lactate oxidase immobilization from water-organic mixtures with a high concentration of organic solvent (90%) leads to advanced lactate biosensors. The use of the new alkoxysilane monomers-(3-aminopropyl)trimethoxysilane (APTMS) and trimethoxy[3-(methylamino)propyl]silane (MAPS)-as the base for enzyme-containing membrane construction resulted in a biosensor with up to a two times higher sensitivity (0.

'Artificial peroxidase' nanozyme - enzyme based lactate biosensor.

In contrast to bienzyme biosensors, we propose the nanozyme-enzyme based ones substituting the enzyme peroxidase with the more active and stable nanoparticles "artificial peroxidase". The use of catalytically synthesized Prussian Blue based nanozymes simplifies assembling of hydrogen peroxide transducer providing its higher sensitivity. For immobilization of lactate oxidase the composite alkoxysilane - perfluorosulfonated ionomer (PFSI) membranes are proposed achieving the significantly improved operating stability.

Noninvasive Diabetes Monitoring through Continuous Analysis of Sweat Using Flow-Through Glucose Biosensor.

We propose monitoring of diabetes through continuous analysis of undiluted sweat immediately after its excretion using a flow-through glucose biosensor. The used biosensors are based on Prussian Blue and glucose oxidase immobilized in perfluorosulfonated ionomer or gel of alkoxysilane; the resulting sensitivity with the latter reaches in batch mode 0.23 A M cm, and the calibration range is from 1 μM to 1 mM (flow-through mode).

Reagentless biosensor based on glucose oxidase wired by the mediator freely diffusing in enzyme containing membrane.

Wiring glucose oxidase in the membrane with an immobilized mediator is possible due to the diffusion ability of the latter, if the enzyme containing membrane is formed according to the proposed protocol, including exposing proteins to water-organic mixtures with the high content of organic solvent. In the course of the study, the new glucose oxidase mediator, unsubstituted phenothiazine, was discovered. The diffusion coefficient of the mediator in the resulting membrane is independent of the presence of enzyme.

Kinetic approach for evaluation of total antioxidant activity.

We propose a novel approach for assessment of total antioxidant activity by monitoring kinetics of hydrogen peroxide (H(2)O(2)) scavenging after its injection into liquid sample under study. H(2)O(2) is known to be the strongest oxidant, really presented in human body in contrast to the majority of the model oxidative systems used for evaluation of antioxidant activity. In addition, kinetic approach, being more informative than the commonly used determination of the final product, obviously provides better discrimination of potential antioxidants.