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Abstract. A new chiral poly(ester-imide) (PEI) was prepared via direct polyesterification of N,N!-(pyromellitoyl)-bis-(L-tyrosine dimethyl ester) and N-trimellitylimido-L-methionine using tosyl chloride/pyridine/N,N!-dimethylformamide system as a condensing agent. The resulting new chiral polymer was obtained in good yield and had good thermal stability as well as good solubility in common organic solvents. After that, PEI/titanium bionanocomposites (PEI/TiO 2 BNCs) were prepared using the modified nanosized TiO 2 via sonochemical reaction that can accelerate hydrolysis, increase collision chance for the reactive system and improve the dispersion of the nanoparticles in polymer matrix. The scanning electron microscopy (SEM), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) results indicated that there is no aggregation of a large quantity of particles. Thermogravimetric analysis (TGA) confirmed that the heat stability of the BNC polymers in the temperature range of 400-800ºC was enhanced by addition of TiO 2 nanoparticles. Furthermore, in vitro toxicity test was employed for assessing the sensitivity of these compounds to microbial degradation. To this purpose, polymer and PEI/TiO 2 BNCs were investigated under soil burial conditions. The results of this study revealed that polymer and its BNCs are biologically active and non-toxic in the natural environment although some antimicrobial properties were found for BNCs.

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A magnetized nano-photocatalyst based on TiO 2 /magnetic graphene was developed for efficient photodegradation of crystal violet (CV). Scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and elemental mapping were used to characterize the prepared magnetic nanophotocatalyst. The photocatalytic activity of the synthesized magnetic nanophotocatalyst was evaluated using the decomposition of CV as a model organic pollutant under UV light irradiation. The obtained results showed that TiO 2 / magnetic graphene exhibited much higher photocatalytic performance than bare TiO 2 . Incorporation of graphene enhanced the activity of the prepared magnetic nano-photocatalyst. TiO 2 /magnetic graphene can be easily separated from an aqueous solution by applying an external magnetic field. Effects of pH, magnetized nano-photocatalyst dosage, UV light irradiation time, H 2 O 2 amount and initial concentration of dye on the photodegradation efficiency were evaluated and optimized. Efficient photodegradation (>98%) of the selected dye under optimized conditions using the synthesized nanophotocatalyst under UV light irradiation was achieved in 25 min. The prepared magnetic nano-photocatalyst can be used in a wide pH range (4-10) for degradation of CV. The effects of scavengers, namely methanol (OH•− scavenger) and disodium ethylenediaminetetraacetate (hole scavenger), on CV photodegradation were investigated.

In this work, core/shell magnetic molecularly imprinted polymer nanoparticles were synthesized for extraction and pre‐concentration of valsartan from different samples and then it was measured with high‐performance liquid chromatography. For preparation of molecularly imprinted polymer nanoparticles, Fe3O4 nanoparticles were coated with tetraethyl orthosilicate and then functionalized with 3‐(trimethoxysilyl) propyl methacrylate. In the next step, molecularly imprinted polymer nanoparticles were synthesized under reflux and distillation conditions via polymerization of methacrylic acid, valsartan (as a template), azobisisobutyronitrile and ethylene glycol dimethacrylate as cross linking. The properties of molecularly imprinted polymer nanoparticle were investigated by FTIR spectroscopy, field emission scanning electron microscopy, and X‐ray diffraction. Box‐Behnken design with the aid of desirability function was used for optimizing the effect of variables such as the amounts of molecularly imprinted polymer nanoparticles, time of sonication, pH, and volume of methanol on the extraction percentage of valsartan. According to the obtained results, the affecting variables extraction condition were set as 10 mg of adsorbent, 16 min for sonication, pH = 5.5 and 0.6 mL methanol. The obtained linear response (r2 > 0.995) was in the range of 0.005–10 µg/mL with detection limit 0.0012 µg/mLand extraction recovery was in the range of 92–95% with standard deviation less than 6% (n = 3).

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Core–shell magnetic molecularly imprinted polymer nanoparticles (MMIP-NPs) were prepared and applied in the extraction of chlordiazepoxide from various samples.