Cauliflower-like cadmium sulfide (CdS) microspheres composed of nanocrystals have been successfully synthesized by a hydrothermal method using poly(ethylene glycol) (PEG) as the template coordination agent and characterized by a variety of methods. Our experiments confirmed that the size of the CdS microspheres could be easily modified by controlling the chain length of PEG. Powder X-ray diffraction and Raman spectroscopy measurements revealed the cubic structure of the CdS microspheres; morphological studies performed by HR-SEM and HR-TEM methods showed the cauliflower-like structure of the synthesized CdS microspheres. Each microsphere was identified to be created by the self-assembly of CdS nanocrystals and is attributed to the oriented aggregation of the CdS nanocrystals around a polymer-Cd(2+) complex spherical framework structure. X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray (EDX) analysis confirmed the stoichiometries of the CdS microspheres. Diffuse reflectance spectrum (DRS) measurements showed that increasing the PEG chain length increased the band gap value of the CdS microspheres slightly, from 1.99 to 2.06 eV. The cauliflower-like CdS microspheres could be applied to photocatalytic degradation studies.

Voltammetric properties and possibility of the determination of carcinogenic aminoderivatives of polycyclic aromatic hydrocarbons, namely 1-and 2-aminonaphthalene and 2-aminobiphenyl, have been investigated. Carbon paste electrodes (CPE) modified with monomeric a-, b-or g-cyclodextrin and carbon-based screen-printed electrodes (SPE) surface-modified with a thin film of b-cyclodextrin (b-CDP) or carboxymethylated b-cyclodextrin (b-CDPA) condensation polymer were used for that purpose as simple electrochemical biosensors. Analytical procedure for the DPV determination of tested amines using these biosensors was proposed. Linear calibration plots within the concentration range of 2 Â 10 À8 ± 2 Â 10 À7 mol dm À3 and 2 Â 10 À7 ± 1 Â 10 À6 mol dm À3 with limits of quantification of the order of 10 À9 mol dm À3 were obtained for the modified CPE and modified SPE.

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