Determination method for total arsenic and partial-digestion method with nitric acid for inorganic arsenic speciation in several varieties of rice.

The determination method of total arsenic (As) and the speciation method of inorganic As for non-glutinous rice reported in our preceding paper were applied to several varieties of rice under optimized experimental conditions. In the determination of total As with ICP-MS, acetic acid was added to increase the sensitivity and an internal reference method with germanium was adopted to increase the precision. The extraction temperature in the partial-digestion method with nitric acid to speciate inorganic As was raised to 100 degrees C, because extraction efficiency over 90% was obtained from glutinous rice and colored rice at this temperature.

[Development and evaluation of determination methods for boric acid in agar using ICP-AES and ICP-MS].

A new test method for boric acid in agar was developed. After digestion with nitric acid, the concentration of boron was measured by ICP-AES or ICP-MS with internal standards. Collaborative studies involving 5 laboratories were conducted to evaluate the new method by using a finely powdered agar sample and a standard sample (NIST SRM SRM1570a).

Evaluation of a nitric acid-based partial-digestion method for selective determination of inorganic arsenic in rice.

Arsenic (As) uptake in human occurs via the food chain mainly. The Joint FAO/WHO Expert Committee on Food Additives has established the provisional tolerable weekly intake level for As as an inorganic As (iAs) value, because iAs in food is much more toxic than organic As. In this study, we studied an acid based partial-digestion method for the complete extraction of arsenicals from rice.

Nitric acid-based partial-digestion method for selective determination of inorganic arsenic in hijiki and application to soaked hijiki.

Because there is a great difference between the toxicity of inorganic arsenic (As) and organic As in food, the JECFA has set a PTWI value for inorganic As (iAs) rather than for total As. The difference in As toxicity makes it necessary to extract iAs completely from food samples for toxicological analysis, but complete extraction of As from most foods including seaweed has not been achieved to date. We developed a partial-digestion method that uses nitric acid as a solvent in order to extract almost all arsenicals from the solid matrix of hijiki (Hizikia fusiforme, a brown alga) samples.

Rapid and improved determination of furan in baby foods and infant formulas by headspace GC/MS.

Furan is a 5-membered ring compound with high volatility. The U.S.

Determination of genotoxic phenylhydrazine agaritine in mushrooms using liquid chromatography-electrospray ionization tandem mass spectrometry.

A new method with good sensitivity and specificity for detecting and quantifying genotoxic hydrazines, agaritine and 4-(hydroxymethyl)phenylhydrazine (HMPH), was developed using liquid chromatography-electrospray tandem mass spectrometry (MS). Synthetic agaritine and HMPH were structurally assigned by 1H-, 13C- and two-dimensional nuclear magnetic resonance (NMR) analysis (HMBC and HMQC), high-resolution fast-atom bombardment (HR-FAB) MS and time of flight (TOF) MS. The polar molecule agaritine was separated on an ODS column using 0.

Analysis of agaritine in mushrooms and in agaritine-administered mice using liquid chromatography-tandem mass spectrometry.

A sensitive and specific method for quantifying a genotoxic hydrazine, agaritine, has been developed using liquid chromatography-electrospray ionization tandem mass spectrometry (MS). Synthetic agaritine was structurally assigned by (1)H, (13)C and two-dimensional nuclear magnetic resonance (NMR) analysis (heteronuclear multiple-bond correlation [HMBC] and heteronuclear multiple-quantum coherence [HMQC]), high-resolution fast-atom-bombardment (HR-FAB) MS. Agaritine was separated on an ODS column using 0.

Binding affinity of aluminium to human serum transferrin and effects of carbohydrate chain modification as studied by HPLC/high-resolution ICP-MS--speciation of aluminium in human serum.

Aluminium (Al) in the blood is bound to transferrin (Tf), a glycoprotein of about 80kDa that is characterized by its need for a synergistic anion. In this focused review, the binding affinity of Al to Tf is surveyed in the context of our recent studies using on-line high-performance liquid chromatography/high-resolution inductively coupled plasma mass spectrometry (HPLC/HR-ICP-MS). Al in human serum without any in vitro Al-spikes was present in a form bound to the N-lobe site of Tf.

Binding patterns of vanadium to transferrin in healthy human serum studied with HPLC/high resolution ICP-MS.

Vanadium (V) is an essential metal for mammals. It has different valence states. In blood, V is bound to transferrin (Tf), a glycoprotein that has two metal-binding sites (C-lobe site and N-lobe site).

Specific determination of bromate in bread by ion chromatography with ICP-MS.

A sensitive method for detecting bromate in bread by ion chromatography with inductively-coupled plasma mass spectrometry (IC/ICP-MS) was developed. Bromate was extracted from bread with water. The clean-up procedure included a 0.

Binding patterns of vanadium ions with different valence states to human serum transferrin studied by HPLC/high-resolution ICP-MS.

Vanadium (V) is an essential metal for mammals and has different valence states. In blood, V is bound to serum transferrin (Tf), a glycoprotein which has two metal-binding sites, and carbonate is generally required for the binding. In this study, the binding patterns of V(III), V(IV), and V(V) to human serum Tf (hTf) were analyzed using an HPLC system equipped with an anion-exchange column and directly connected to a high-resolution inductively coupled plasma-mass spectrometer for metal detection (51V).