New polymeric microspheres containing azomethine (1a-1c and 2a-2c) were synthesized by condensation to compare the enzymatic properties of the enzyme glucose oxidase (GOx) and to investigate antimutagenic and antimicrobial activities.The polymeric microspheres were characterized by elemental analysis, infrared spectra (FT-IR), proton nuclear magnetic resonance spectra, thermal gravimetric analysis, and scanning electron microscopy analysis. The catalytic activity of the glucose oxidase enzyme follows Michaelis-Menten kinetics. Influence of temperature, reusability, and storage capacity of the free and immobilized glucose oxidase enzyme were investigated. It is determined that immobilized enzymes exhibit good storage stability and reusability. After immobilization of GOx in polymeric supports, the thermal stability of the enzyme increased and the maximum reaction rate (V max ) decreased. The activity of the immobilized enzymes was preserved even after 5 months. The antibacterial and antifungal activity of the polymeric microspheres were evaluated by well-diffusion method against some selected pathogenic microorganisms. The antimutagenic properties of all compounds were also examined against sodium azide in human lymphocyte cells by micronuclei and sister chromatid exchange tests. K E Y W O R D Santimicrobial property, antimutagenic effect, glucose oxidase, Polymeric microsphere, Pt 4+ -azomethine

In the present study, a novel biosensor that is sensitive to glucose was prepared using the microspheres modified with (4-formyl-3-methoxyphenoxymethyl)polystyrene (FMPS) with l-glycine. Polymeric microspheres having Schiff bases were prepared from FMPS using the glycine condensation method. Glucose oxidase enzyme was immobilized onto modified carbon paste electrode by cross-linking with glutaraldehyde. Oxidation of enzymatically produced H O (+0.5 V vs. Ag/AgCl) was used for determination of glucose. Optimal temperature and pH were found as 50 °C and 8.0, respectively. The glucose biosensor showed a linear working range from 5.0 × 10 to 1.0 × 10 M, R = 0.999. Storage and operational stability of the biosensor were also investigated. The biosensor gave perfect reproducible results after 20 measurements with 3.3% relative standard deviation. It also had good storage stability.

Pt(ii) and Pt(iv)-tagged nanoparticles have been synthesized according to the template method for the identification of pesticides. Their morphologies have been investigated using scanning electron microscopy and characterized by means of spectral measurements. Then, acetylcholinesterase (AChE) was immobilized onto the nanoparticles. The AChE immobilized Pt(ii) and Pt(iv)-tagged nanomaterials show high reusability and storage capacity. The catalytic activity of AChE followed Michaelis-Menten kinetics. Assays for enzyme activity measurements demonstrate that the nanospheres tagged with Pt(ii) have a much better performance than those with Pt(iv). Furthermore, whether or not there was any interaction between the immobilized enzyme and 1-naphthyl-N-methylcarbamate, which is a carbamate insecticide, was examined.

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A good novel double ferrocene-tagged nanomaterial is designed for glucose determination and its recycling stability. Double Ferrocene-tagged nanomaterial displays higher catalytic activity toward the glucose oxidation than non-ferrocene-tagged nanomaterial. In this study novel nanoparticles including double ferrocene, N-f2-[Bis(2-aminoethyl)amino]ethylgaminomethyl-polystyrene (2AEPS) and ferrocene aldehyde (Fc) have been synthesized by means of condensation and investigated the enzymatic properties of glucose oxidase enzyme (GOD) immobilized on there. Double ferrocene-tagged nanomaterial-GOD shows high reusability and storage capacity and fast incubation time determination of glucose. 2AEPSFc-GOD retains more than 15% of the initial activity after forty five successive cycles, which is a perfect performance.