Preparation and characterization of Rutin loaded on magnetic graphene quantum dot nano career with metals (Ag, Zn, Mg, Co, and Fe) and study of antioxidant and electrochemical properties.

Rutin, is one of the flavonoids, and has high antioxidant properties, but is limited due to low solubility in aqueous solutions. To increase the antioxidant performance and permeability, the synthesis of magnetic graphene quantum dot metal nanocomposites and the antioxidant activity of the prepared nanocomposites have been studied. Rutin was treated with metal magnetic nanocomposites, GQD-MFe2O4, that included metals like Silver, Magnesium, Zinc, Cobalt, and Iron. The metal nanocomposites reacted with Rutin to obtain Rutin-bearing magnetic nanocomposites. The GQD-MFe2O4 nanocomposites were synthesized by common hydrothermal pyrolysis of citric acid and subsequent the addition of iron nitrate and metal nitrate (M= Ag, Mg, Co, Zn, Fe) to the media. The scavenging test of free radical activity and DPPH test of prepared nanomagnetic composites show good antioxidant activity. The results show that the derivatives of magnetic nanocomposites have different antioxidant activities compared to Rutin as ordered: GQD-ZnFe2O4-Ru

Monitoring of enzymatic hydrolysis of penicillin G by pyrolysis-negative ion mass spectrometry.

A pyrolysis-negative ion mass spectrometry (Pyr-NIMS) is used for the monitoring of enzymatic hydrolysis of penicillin G (Pen G) to 6-aminopenicillanic acid (6-APA) and phenyl acetic acid (PAA). The high sensitivity and rapid response time of Pyr-NIMS allow its application to the simultaneously determination of these compounds. The mass to charge (m/z) values of 262, 156 and 135 of Pen G, 6-APA and PAA respectively, are used for the quantitative measurements by selected ion monitoring (SIM). The limit of detection (LOD), linearity and relative standard deviation (n=5) are 10 ng ml(-1), 100 ng ml(-1)-1000 mg ml(-1) and 1.5%, respectively The results are compared with high performance liquid chromatography (HPLC). An important advantage of the presented analytical system is the high linearity of signals without preliminary separation and recalibration. The main and interactive effects of pH, temperature and concentration of Pen G for enzymatic hydrolysis of Pen G are studied. Optimize conditions of pH (8), temperature (28 degrees C) and concentration of Pen G (12% w/v) in real samples are obtained.