Adsorption method may play an important role to remove ochratoxin A (OTA) from wine by bentonite (B), nonylammonium bentonite (NB), dodecylammonium bentonite (DB), KSF-montmorillonite (KSF), and chitosan bead (CB). The optimum conditions of OTA adsorption from synthetic solutions were revealed at room temperature and pH 3.5. The adsorption equilibria of B and NB were almost established within 120 and 240 min, respectively. DB, KSF, and CB had about 90 min of equilibration time. The adsorption efficiency carried out in the synthetic OTA solution did not change remarkably when the amounts of adsorbents were 25 mg for bentonite, DB, and KSF and 100 mg for NB and CB. Furthermore, 25 mg of adsorbents was used at all adsorption studies in synthetic solution. The adsorption isotherm was fitted with mostly a Freundlich equation with respect to the correlation coefficients. The adsorption data were evaluated using Langmuir and Freundlich equations having Kf values ranging from 0.011 to 9.5 with respect to correlation coefficients (R2 = 0.900-0.977). DB and KSF have the highest adsorption capacity for OTA in synthetic solutions. In wine, the removal of OTA was succeeded at a percentage of 60-100 by KSF and CB. Furthermore, the highest adsorption capacity of OTA for red wine was obtained by using 250 mg of KSF, which caused less damage to the nature of wine and also low adsorption of polyphenols and anthcyans.

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& A method was developed for separation and quantitative determination of mercury, copper, cobalt, and zinc as porphyrin complexes using newly synthesized tetra-(3-bromo-4-hydroxyphenyl) porphyrin (TBHPP), tetra-(4-phenoxyphenyl) porphyrin (TPPP) and tetra-p-chloromethylphenyl porphyrin (CMPP) in aqueous medium by HPTLC densitometry. The method involves enrichment of metal ions as metal complexes with octadecyl cartridges and elution using tetrahydrofuran. The analysis was performed on HPTLC silica gel plates with acetone-chloroform (2:8, v=v) as the mobile phase for TBHPP and TPPP quantification and dichloromethane-chloroform-hexane (1:1:3, v=v) for CMPP quantification. Quality parameters were confirmed and detection limits were ranged from 0.16 to 0.92 ng lL À1 . Detection was performed densitometrically in absorption-reflection mode around 420 nm. The method was found to be simple, precise and accurate for the determination of these metal ions in water and food sample.

The migration behavior of aryl-substituted porphyrins and their metalloporphyrins with Zn(II), Ni(II), and Cu(II) were studied in high-performance thin-layer chromatography systems with silica gel and RP(18) plates using different organic mobile phases having different polarities. The (bromohydroxy)phenyl, (phenoxy)phenyl, and oxy(acetic acid)phenyl porphyrins migrated at similar rate. Chloromethylphenylporphyrin was weakly adsorbed on silica gel using either polar or nonpolar mobile phases. The mobility of metal complexes generally tends to increase in the given order of central metal ions: Zn(II) < Ni(II) < Cu(II) on silica gel. The favorable mobile phase for the separation of ligands and the metalloporphyrins is a mixture of acetonitrile-benzene.