Fullerene-C60-modified electrode as a sensitive voltammetric sensor for detection of nandrolone--an anabolic steroid used in doping.

The sorption interactions of oxytetracycline with goethite, hematite, and two iron oxide-rich soils were investigated using batch sorption experiments. Oxytetracycline sorption coefficients for goethite and hematite increased with pH to maximum values at pH ∼8. The sorption edge shape and desorption treatments were consistent with a surface complexation mechanism and could be described by the interaction of divalent anion species with the oxide surface. Oxytetracycline sorption to Georgeville and Orangeburg Ultisol soils decreased with pH. Chemical digestion treatments were used to deduce that soil sorption occurred by complexation to oxide coatings on clay and quartz grains. These results indicate that sorption models must consider the interaction of oxytetracycline, and other similar ionogenic compounds, with soil oxide components in addition to clays and organic matter when predicting sorption in whole soils.

Sorption of oxytetracycline to iron oxides and iron oxide-rich soils.

Photocatalytic degradation kinetics and mechanism of environmental pharmaceuticals in aqueous suspension of TiO2: A case of sulfa drugs

Recent development in derivative ultraviolet/visible absorption spectrophotometry: 2004-2008: a review.

Dopamine (DA) is the most important catecholamine in the brain, as it is the most abundant and the precursor of other neurotransmitters. Degeneration of nigrostriatal neurons of substantia nigra pars compacta in Parkinson's disease represents the best-studied link between DA neurotransmission and neuropathology. Catecholamines are reactive molecules that are handled through complex control and transport systems. Under normal conditions, small amounts of cytosolic DA are converted to neuromelanin in a stepwise process involving melanization of peptides and proteins. However, excessive cytosolic or extraneuronal DA can give rise to nonselective protein modifications. These reactions involve DA oxidation to quinone species and depend on the presence of redox-active transition metal ions such as iron and copper. Other oxidized DA metabolites likely participate in post-translational protein modification. Thus, protein-quinone modification is a heterogeneous process involving multiple DA-derived residues that produce structural and conformational changes of proteins and can lead to aggregation and inactivation of the modified proteins.

Dopamine, Oxidative Stress and Protein–Quinone Modifications in Parkinson's and Other Neurodegenerative Diseases

Spectrophotometric and atomic absorption spectrometric determination of ramipril and perindopril through ternary complex formation with eosin and Cu(II).

Spectrophotometric and AAS determination of ramipril and enalapril through ternary complex formation.

Spectrophotometric and spectrofluorimetric methods for analysis of tramadol, acebutolol and dothiepin in pharmaceutical preparations.

Spectrophotometric and atomic absorption spectrometric determination of certain cephalosporins

Spectrophotometric and spectrofluorimetric methods for analysis of acyclovir and acebutolol hydrochloride

Magda M. Ayad

Papers

Spectrophotometric and atomic absorption spectrometric determination of ramipril and perindopril through ternary complex formation with eosin and Cu(II).

Spectrophotometric and AAS determination of ramipril and enalapril through ternary complex formation.

Spectrophotometric and spectrofluorimetric methods for analysis of tramadol, acebutolol and dothiepin in pharmaceutical preparations.

Spectrophotometric and atomic absorption spectrometric determination of certain cephalosporins

Spectrophotometric and spectrofluorimetric methods for analysis of acyclovir and acebutolol hydrochloride