New analytical device to assess the redox state of Edificio CEEI | Parque Tecnologico de Asturias, 33428 Llanera, Asturias [email protected]

BRS DEVICE BRS (BQC Redox System) is the first multiparametric portable device based on electrochemistry designed to assess the redox state of biomedical samples. With one single device, it is possible to determine different markers of the redox state in a simple, fast and precise way. The device is now available and ready for the measurement of Total Antioxidant Capacity (TAC) and H2O2 Scavenging Activity in a wide variety of biological samples. The device has been designed for a continuous upgrading and improvement through the incorporation of new redox measurements. BRS performance has been...

BRS DEVICE HOW TO USE BRS DEVICE The use of the BRS device is very simple. Insert the test strip into the device, place a drop of sample onto the test strip, and start the measurement. The device is controlled by a specially designed App to use on your mobile device. BRS App functions include running the measurements and storing and sharing the data. In approximately 1 minute results are displayed on your mobile device. Click the button to turn on the BRS Pair your mobile with the BRS device using Bluetooth Insert the strip and place the drop of sample Some Technical data Weight ±250 g Power...

WHAT IS OXIDATIVE STRESS? Oxidative stress is an imbalance between the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) and the ability of the antioxidants present in an organism to fight them. Oxidative stress is responsible for ageing and has been related to different pathologies like obesity, diabetes, cancer, and neurodegenerative disease. The balance between ROS/RNS and antioxidants is critical in maintaining healthy biological systems. Exposure to pathogens, bad life style, smoking, pollution, UV light or malnutrition are some of the factors that can promote...

BRS DEVICE Determining the degree of oxidative stress is therefore of great interest to study:  Disease prevention, control and treatment. Aging process. Effect of lifestyles (diet, sport) on health. WHY ELECTROCHEMISTRY TO STUDY OXIDATIVE STRESS? Redox reactions are involved in the origin and consequences of oxidative stress. Electrochemistry is recognized as the best tool to study this type of reactions. Another important aspect in favour of the electrochemical methods to study oxidative stress, is the electroactivity of most of the oxidants and antioxidants present in biological samples....

TOTAL ANTIOXIDANT CAPACITY (TAC) WHAT IS TAC? Total antioxidant capacity (TAC) is a global measurement of the non-enzymatic antioxidant defense system that integrates the individual effect of all antioxidants in a given matrix, and their additive, synergistic or antagonistic interactions. TAC is considered an important parameter to establish the redox state of biological samples and can be used as an oxidative stress biomarker. METHODS FOR TAC DETERMINATION Due to the lack of standard quantification methods for TAC determination a wide variety of assays have been used to asses the antioxidant...

Table 1. Comparison of methods for TAC determination. TAC Spectrophotometric Method Method ORAC BRS overcomes main limitations of spectrophotometric TAC methods and provides additional information about the electron transfer ability of antioxidants. BRS DEVICE FOR TAC ANALYSIS BRS electrochemical device provides a rapid, simple and sensitive alternative to spectrophotometric assays for TAC determination. BRS uses a voltammetric technique to measure TAC. The sample is electrochemically oxidized by applying a potential scan and TAC value is calculated from the voltammetric charge. Similar to ET...

REDOX TECHNOLOGIES BRS analysis does not require toxic reagents and even colored or turbid samples can be analyzed. BRS TAC results are expressed in terms of electric charge (^C) as Qi, Q2 and Qt. BRS device, thanks to electrochemistry, also provides information about how easy or difficult is to oxidize the antioxidants present in a sample. Q1. Antioxidant capacity related to low redox potential antioxidants. Easy electron transfer/High antioxidant activity. Q2. Antioxidant capacity related to high redox potetial antioxidants. More difficult electron transfer/Low antioxidant activity. Qt. Total...

Intra-assay precision was evaluated by replicate analysis (n=10) of a human serum sample using a new strip for each measurement. Inter-assay precision was calculated by measuring a standard solution (100 |jM Ascorbic Acid) on ten different days using a new strip for each measurement. BRS analysis shows good precision with intra and inter-assay coefficients of variation (CV) < 10 %.

H2O2 SCAVENGING ACTIVITY WHY IS IMPORTANT TO MEASURE H2O2 SCAVENGING ACTIVITY? Hydrogen peroxide (H2O2) is formed in cells by controlled pathways and trigger a broad spectrum of cellular response. Locally intense amounts of H2O2, produced for example by inflammatory cells, can also cause oxidation of proteins, lipids and DNA. Despite its poor reactivity, H2O2 in the presence of transition metal ions forms the extremely reactive hydroxyl radical by Fenton chemistry. H2O2 can also selectively oxidize some methionine and cysteine residues in certain proteins and is a substrate for myeloperoxidase,...

BRS H2O2 Scavenging Activity measurement is based on the electrochemical oxidation of H2O2 in the absence and presence of scavengers. BRS uses a voltammetric technique to measure the anodic current related to H2O2 oxidation using a specially designed test strips. H2O2 test strips are manufactured using a modified carbon material that exhibits electrocatalytic properties towards H2O2 oxidation. Table 5. Comparison of methods for H2O2 Scavenging Activity determination. Optical Methods H2O2 Scavenging Activity BRS H2O2 Scavenging Activity is expressed as % using the following equation: Where iO...

BRS H2O2 SCAVENGING ACTIVITY SAMPLE ANALYSIS Table 6 shows the % of H2O2 Scavenging Activity calculated for several biological samples (healthy donors). Results are not directly comparable due to the different dilution of the samples. Samples were diluted in 50 mM PB pH 7. Red bloos cells were lysed by adding four times their volume of ice cold ultra-pure water followed by a centrifugation step at 10000 x g for 15 min at 4° C. Incubation time: 5 min at RT. Table 6. BRS H2O2 Scavenging Activity for biomedical samples.