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Poly(maleic anhydride-co-styrene) (MAST) was synthesized by a free-radical polymerization reaction. A bioactive molecule, procainamide hydrochloride (PH), was then conjugated to MAST. The conjugation product was named as MAST/PH. Structural characterization of MAST and MAST/PH was carried out by Fourier Transform Infrared and Nuclear Magnetic Resonance spectroscopy. Their molecular weights were determined by size-exclusion chromatography. A mechanism was then suggested for the conjugation reaction. The results of the cytotoxicity assay, employing a mouse fibroblast cell line (L929), indicated that MAST/PH had no cytotoxicity at concentrations [Formula: see text] 62 μg mL(-1) (p > 0.05). Antiproliferative activities of MAST/PH and PH were determined by the BrdU cell proliferation ELISA assay, using C6 and HeLa cell lines. In the experiment, two anticancer chemotherapy drugs, cisplatin and 5-fluorouracil, were included as positive control. Antiproliferative activity results demonstrated that MAST/PH yielded the highest suppression profile (approximately 42%) at 20 μg/ml, while free PH exerted the same activity at 100 μg/ml. Interestingly, both MAST/PH and PH suppressed the proliferation of only one of the cell lines, C6 cells. Both cisplatin and 5-fluorouracil yielded approximately 60% antiproliferative activity on C6 cells at 20 and 100 μg/ml concentrations. Antiangiogenic capacity of both MAST and MAST/PH was also investigated by using the chicken chorioallantoic membrane assay. Results obtained indicated that while MAST/PH could be included into the category of good antiangiogenic substances, the activity score of MAST was within the weak category.

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In this paper, the complex formation of bovine serum albumin (BSA) and polyacrylic acid (PAA) in the presence metal ions at pH = 7 has been examined by using fluorescence and dynamic light scattering measurements. It has been observed that the most stable complexes of polyacrylic acid and bovine serum albumin have occurred in the presence of copper(II) ions. The other ions have the ability to form weak complexes between polyions and bovine serum albumin. To prior characterizing the interaction between bovine serum albumin and polyacrylic acid, the dynamic light scattering technique have been applied to determine the intensity-size distributions of the solutions of bovine serum albumin, polyacrylic acid, and ternary mixtures containing various molar ratios of bovine serum albumin to polyacrylic acid (the molar ratios of bovine serum albumin to polyacrylic acid has been taken equal to 0.5, 1.0, 1.5, 2.0 and 2.5) prepared at different molar ratios of copper(II) ions/acrylic acid unit. When the molar ratio of copper(II) ions to acrylic acid in the ternary mixtures has been lower than and equals to 0.3, two peaks have been observed in the curves of the intensity-size distributions due to contents of free bovine serum albumin and ternary complexes of polyacrylic acid-copper(II)-bovine serum albumin whereas when the molar ratio of copper(II) ions to acrylic acid equals to 0.4, the hydrodynamic diameter has pointed out only one peak. This result indicates that soluble and stable ternary complexes has occurred when the molar ratio of copper(II) ions to acrylic acid has been taken equal to 0.4.

The binary and ternary complex formations of poly(methyl vinyl ether-co-maleic anhydride) (PMVEMA) with copper ions and with bovine serum albumin (BSA) in the presence of copper ions in phosphate buffer solution at pH = 7 were examined by the techniques of UV-visible, fl uorescence, dynamic light scattering, atomic force microscopy measurements. In the formation of binary complexes of PMVEMA-Cu(II), the addition of copper ions to the solution of PMVEMA in phosphate buffer solution at pH = 7 forms homogeneous solutions when the molar ratio of Cu(II)/MVEMA is 0.5. Then the formations of ternary complexes of PMVEMA-Cu(II)-BSA were examined. Study analysis revealed that the toxicities of polymer-metal and polymer-metal-protein mixture solutions depend on the nature and ratio of components in mixtures.

Antioxidants can protect normal cells from reactive oxygen species as a protective agent. Therefore, it is important to know radiation attenuation properties of antioxidants. In the present study, nine different types of antioxidant samples were investigated using Monte Carlo simulation method. MCNPX general-purpose Monte Carlo code (version 2.6.0) was utilized to investigate the attenuation parameters of antioxidant samples such as Rosmarinic acid, Butylhydroxyanisole, Butylhydroxytoluene, Morin, Piperonyl butoxide, Ascorbyl Palmitate, Citric acid, Malic acid, and Nordihydroguaiaretic acid. The mass attenuation coefficients (μ/ρ) values have been calculated against photon energies of 0.122, 0.356, 0.511, 0.662, 1.173 and 1.33 MeV. From these values, the effective atomic number (Z eff ), mean free path (MFP) and half value layer (HVL) have been calculated and compared with XCOM data. The results obtained by the MCNPX Monte Carlo code were close to those of standard XCOM data. The obtained results showed that the attenuation of photons in antioxidant samples increased with decreasing energy. Z eff values for the selected antioxidants molecules varied between 3.75-4.787. It is also found that malic acid and citric acid have smaller HVL values comparing with rest of antioxidants examined. It can be concluded that, modeled and validated standard MCNPX geometry could be useful to the scientific community for similar future radiation-attenuation studies using different types of biological materials and biological systems.

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