Measurements of aldehydes and ketones are typically conducted by derivatization using sorbent cartridges coated with 2,4-dinitrophenylhydrazine (DNPH). The collected samples are eluted with acetonitrile and analyzed by high-pressure liquid chromatography coupled with an ultra-violet detector (HPLC/UV). This paper intends to examine artifacts about its suitability in identification of unsaturate...

Carbonyl compound emissions from two passenger cars fueled with different methanol/gasoline blends (M15 and M100) and operated with three-way catalytic converters (TWC) were investigated. The tests were performed on a chassis dynamometer with constant volume sampling over the New European Driving Cycle (NEDC). Carbonyls were trapped on dinitrophenylhydrazine (DNPH) cartridges. The hydrazones fo...

In connexion with studies on the N-terminal groups of histones (Phillips, 1961), a method was needed for measuring about 0-1 ,umole of aliphatic acyl groups derived from a few milligrams of protein. Initial experiments were done in which acetylamino acids and ovalbumin were hydrolysed in sulphuric acid and an ether extract was chromatographed, by using modifications of the method of Brown & Hal...

Neuroserpin, a member of the Serine Proteinase Inhibitor (Serpin) superfamily, is known to be a neuroprotective factor in the focal ischemic stroke followed by reducing the microglial activation. Neuroserpin is a protein rich of methionine residues that can scavenge the free radical species which may increase its neuroprotective effect. On the other hand, the oxidative modifications of the amin...

This study concerns the oxidation of n-hexane. It was conducted in continuous flow fused-silica jet-stirred reactor (JSR) at 10 atm and an equivalence ratio 0.5. n-Hexane initial concentrations were (i) 2500 ppm with a mean residence time 1.5 s (ii) 1000 0.7 s; we operated cool-flame regime for temperatures ranging from 540 to 720 K 530 800 K, respectively. Products analyzed quantified gas phas...

Mass spectrometry (MS) of 'carbonylated proteins' often involves derivatization of reactive carbonyl groups to facilitate their enrichment, identification and quantification. Among the many reported reagents, 2,4-dinitrophenylhydrazine (DNPH), biotin hydrazide (BHZ) and O-(biotinylcarbazoylmethyl) hydroxylamine (ARP) are the most frequently used. Despite their common use in carbonylation resear...

OBJECTIVE The purpose of our study was to investigate the effect of the mode of delivery on the oxidant and antioxidant system in umbilical cord blood. METHODS We performed gas analysis of umbilical venous blood and umbilical arterial blood immediately after delivery in 38 women; eighteen women had a vaginal delivery while 20 women delivered via cesarean section at over 37 weeks gestation. We...

A novel analytical method for determining formaldehyde (FA) in aqueous samples was developed with a miniaturized extraction capillary in high-performance liquid chromatography (HPLC). The extraction capillary was prepared by packing silica gel particles in a stainless steel capillary of 0.8 mm i.d. and 1.6 mm o.d. A derivatization reagent of 2,4-dinitrophenylhydrazine (DNPH) was impregnated on ...

Raman spectroscopy and Raman imaging were used to examine several types of carbon electrode materials, including glassy carbon (GC) and highly ordered pyrolytic graphite (HOPG). Variations in the intensity ratio of the D and E2g Raman bands across the carbon surface indicated varying carbon microstructure. The D/E2g ratio for polished GC and pyrolytic graphite edge (PG) was relatively constant,...

Oxidative stress, an imbalance toward the pro-oxidant side of the pro-oxidant/antioxidant homeostasis, occurs in several human diseases. Among these diseases are those in which high levels of protein carbonyl (CO) groups have been observed, including Alzheimer's disease (AD), rheumatoid arthritis, diabetes, sepsis, chronic renal failure, and respiratory distress syndrome. What relationships mig...