Application of biosynthesized ZnO nanoparticles on an electrochemical H 2 O 2 biosensor

ABSTRACT ZnO nanoparticles (NPs) were synthesized via a green biochemical method using Corymbia citriodora leaf extract as a reducing and stabilizing agent. The biosynthesized ZnO NPs were characterized by SEM and XRD. An electrochemical H2O2 biosensor was fabricated by modification of a glassy carbon electrode using our proposed ZnO NPs. The electrochemical sensor showed excellent detection performance towards trace amounts of H2O2, demonstrating that it could potentially be used in clinical applications.

Green synthesis and characterization of Manganese nanoparticles using natural plant extracts and its evaluation of antimicrobial activity.

Green synthesis of metal nanoparticles is an interesting and expanding research area due to the potential applications for the ecofriendly development of novel technologies. Generally, nanoparticles are prepared by a variety of chemical and physical methods which are yield environmentally benign wastages largely. Present study reported a simple, convenient and low cost method for the synthesis of manganese nanoparticles by reducing manganese acetate with the help of easily available natural products viz., lemon extract as reducing agent and turmeric curcumin as a stabilizing agent. The curcumin was isolated from turmeric by using solvent extraction method and used for manganese nanoparticle stabilization. The characterization of curcumin and manganese nanoparticles was done by using UV- Vis and FT-IR spectroscopic techniques. The morphology of manganese nanoparticles was confirmed by SEM and TEM techniques. The size of MnNPs was in the ranges about 50nm. The antimicrobial activities of synthesized Mn nanoparticles were observed higher antimicrobial activity than the standard drug against S. aureus, C. lunata and T. simii and also exhibited similar inhibition activity to standard drug against E. coli, C. albicans, and A. niger.

Preparation of niclosamide ethanolamine nano-suspension and its molluscicidal effect / 中国血吸虫病防治杂志

Objective To prepare a novel nano-suspension of niclosamide ethanolamine and evaluate its molluscicidal effect. Methods Niclosamide ethanolamine and stabilizing agent—polyvinylpyrrolidone (PVP) were dissolved in dimethyl sulfoxide. After the solution was added into water under fast stirring, niclosamide ethanolamine was quickly precipitated to form nanoparticles and nano-suspension was obtained. The weight ratio of PVP to niclosamide ethanolamine, concentration, temperature, stirring speed on the size and distribution of the nanoparticles were investigated. The molluscicidal effect of niclosamide ethanolamine nano-suspension was measured by immersion and spray methods in the laboratory and field. Results When the weight ratio of PVP to niclosamide ethanolamine was from 1∶2 to 1∶3, the nanoparticles of the niclosamide ethanolamine had diameters about 100 nm and the nano-suspension was stable without agglomerating for more than 1 month; as the speed of the stirring increased, the nanoparticles prepared became smaller and more stable. LC50 of the nano-suspension was 0.0544 mg/L but the LC50 of wettable powder of niclosamide ethanolamine salt (WPN) was 0.1250 mg/L. In the field immersion and spray tests, the concentration of nano-suspension as only 1/5 of active content of WPN achieved the same molluscicidal effect with WPN. Conclusions The nano-suspension has higher molluscicidal effect than WPN and the novel formulation of niclosamide has more advantages than WPN, it is useful for snail control in the field.