Rapid and sensitive smartphone non-enzymatic colorimetric assay for the detection of glucose in food based on peroxidase-like activity of Fe3O4@Au nanoparticles.

A low-cost and reliable analytical method based on the combination of a newly designed Fe3O4@Au as peroxidase mimetics, supported on smartphone analysis software package was proposed for the determination of glucose content in food samples. The nanocomposite was prepared by self-assembling technique, and the characterization was carried out using transmission electron microscopy (TEM), Fourier transforms infrared, and X-ray diffractometer. Record the color change of the solution with a smartphone camera and optimize the operation parameters and reaction conditions. A smartphone with a free self-developed app was accustomed live the RGB (red-greenblue) values of color intensity within the Fe3O4@Au system and were processed with Image J software before computationally convert them glucose concentrations. At the optimization experiment, reaction temperature of 60 °C, reaction time of 50 min and the amount of addition of Fe3O4@Au 0.0125 g was the optimal combination of detecting glucose smartphone color detection system. Hereon, the accuracy of the proposed method was evaluated by comparison between smartphone colorimetry and UV-vis spectrophotometer, a linear calibration in the range of 0.25 âˆ¼ 15 mmol/L glucose was obtained with minimum detection limit of 1.83 and 2.25 µmol/L, respectively. The proposed method was applied effectively to the detection of glucose in actual samples. The results were in accordance with the conventional UV-vis spectrophotometer method.

High Fischer ratio peptide of hemp seed: Preparation and anti-fatigue evaluation in vivo and in vitro.

The high Fischer (F) ratio hemp peptide (HFHP) was prepared by enrichment using activated carbon adsorption, ultrafiltration, and Sephadex G-25 gel filtration chromatography. The OD220/OD280 ratio reached 47.1 with a molecular weight distribution from 180 to 980 Da, a peptide yield up to 21.7 %, and the F value was 31.5. HFHP had high scavenging ability of DPPH, hydroxyl free radicals, and superoxide. Mice experiments showed that the HFHP increased the activity of superoxide dismutase and glutathione peroxidase. The HFHP had no effect on the body weight of mice, but prolonged their weight-bearing swimming time. The lactic acid, serum urea nitrogen, and malondialdehyde of the mice after swimming was reduced, and the liver glycogen increased. The correlation analysis indicated that the HFHP had significant anti-oxidation and anti-fatigue properties.

A smartphone-integrated dual-mode nanosensor based on Fe3O4@Au for rapid and highly selective detection of glutathione.

A simple, rapid and straightforward method for detecting reduced glutathione (GSH) was developed supported on smartphone analysis software package and a peroxide simulated catalyst nanoparticles (Fe3O4@Au) system. The nanocomposite was prepared by self-assembling technique, and the characterization was carried out using transmission electron microscopy, Fourier transforms infrared, and X-ray diffractometer. Fe3O4@Au materials have catalyzed the oxidation of a typical colorimetric substrate in the presence of H2O2, with the color changes from colorless to green oxidized. A smartphone with a free self-developed app referred to as "Color Capture" was accustomed live the RGB (red-greenblue) values of color intensity within the Fe3O4@Au system and computationally convert them GSH concentrations. The smartphone detection system showed high property and sensitivity of GSH detection. It gave a constant correlation (R2 = 0.9973) between the colour intensity of I and the GSH concentration, with a linear vary of 0-0.25 mmol/L, and a detection limit of 0.013 µmol/L. The results obtained were most consistent with the results obtained in ultraviolet spectrophotometry. The colorimetric system is based on smartphone analysis software developed to detect GSH in actual samples with potential application values.