HPLC Fluorescence Method for Eugenols in Basil Products Derivatized with DIBI.

Eugenols (Eugs) such as eugenol (Eug), methyleugenol (MeEug), and linalool (Lin) in basil product are the main bioactive components of basil products and have a terminal double-bond. A sensitive HPLC-fluorescence method for Eugs derivatized with 4-(4,5-diphenyl-1H-imidazol-2-yl)iodobenzene (DIBI) was developed. Good separation of DIB-Eugs was achieved within 20 min on an Atlantis T3 column (50 × 2.1 mm i.d., 3 µm) with a mobile phase of methanol-water. The calibration curves obtained with Eug standards showed good linearities in the range of 0.1-50 µM (r ≥ 0.999). The limits of detection at a signal-to-noise ratio (S/N) = 3 for Eug, MeEug, and Lin were 1.0, 6.0, and 4.8 nM, respectively. The limits of quantitation (S/N = 10) of the Eugs were lower than 19.9 nM. The accuracies for the Eugs were within 96.8-104.6%. The intra- and inter-day precisions as relative standard deviations for the Eugs were less than 1.2 and 9.6% (n = 3). The recoveries of Eug, MeEug, and Lin were 99.0 ± 0.1, 98.0 ± 0.2, and 96.0 ± 0.4% (n = 3), respectively. The DIB-Eugs were confirmed to be stable for 2 h (>90%) at room temperature and 24 h (>95%) at 4 °C. These parameters of the proposed method were useful for the simultaneous determination of Eugs in basil products. Therefore, the developed method may be a powerful tool for the quality evaluation of dried commercially available basil products.

[Identification and Quantification of 2-Iodo-4-methylphenol in Milk].

It is well-known that a strange flavor, known as off-flavor, might be found in various food products. Even though these substances do not affect our body directly, they can cause a significant change in food flavor and smell, thereby lowering the quality of food products. A well-known example of off-flavor is the transfer of smell from one food product to another. We have previously studied how the smell of limonene, a flavor component of orange juice in paper cartons, is transferred from unopened packages to milk stored in paper cartons, and have confirmed cases where the milk develops a smell completely different from that of limonene. This smell was also confirmed to not have originated from orange juice, and was found to be similar to that of a halogenated phenol. This study aimed to identify this odor component, and our findings indicate the off-flavor component to be 2-iodo-4-methylphenol.

Rapid Identification of Unknown Organic Iodine in Small-Volume Complex Biological Samples Based on Nanospray Mass Spectrometry Coupled with in-Tube Solid Phase Microextraction.

A new method for rapid screening of unknown organic iodine (OI) in small-volume complex biological samples was developed using in-tube solid phase microextraction (SPME) nanospray mass spectrometry (MS). The method proposed a new identification scheme for OI based on nanospray high-resolution mass spectrometry (HR-MS). The mass ranges of OI ions were confirmed using the t-MS2 scan mode first; then, the possible precursor ions of OI were selected and identified orderly in full MS/ddMS2 and t-MS2 scan modes. Besides, in-tube SPME was used for the pretreatment of small-volume biological samples, and it was the first time in-tube SPME combined with nanospray MS for OI identification. The whole analysis procedure took only 8 min and consumed 50 µL per sample. Using the new method, six kinds of OI added to urine and an unknown OI C12H23O11I in human milk were successfully identified. Moreover, the proposed identification scheme is also suitable for other ambient mass spectrometry (AMS) to determine unknown compounds with characteristic fragment ions.

Selective Identification of Organic Iodine Compounds Using Liquid Chromatography-High Resolution Mass Spectrometry.

A method to selectively and sensitively detect organic iodine compounds and identify their structures has been developed using liquid chromatography-high resolution mass spectrometry (LC-HRMS). Using extracted ion chromatograms of product ions (iodine ion) collected on a rapid scanning quadrupole orbitrap mass spectrometer, the retention times of the unknown organic iodine compounds were determined, and the structural information were acquired according to the MS/MS experiments and the matching with reference standards. We have demonstrated the application of this method by identifying unknown organic iodine compounds in seaweed. A total of 28 possible organic iodine peaks were discovered, among them, the accurate mass and element composition of the corresponding precursor ions were identified for 12 peaks, and molecular structures were confirmed for 4 peaks, which were 3-iodo-L-tyrosine, 3,5-diiodo-L-tyrosine, 4-iodophenol, and 2-iodobenzoic acid. This method is expected to lead to the future discovery of new organic iodine compounds via LC-HRMS in different environmental samples, which is crucial for understanding the iodine biogeochemical cycling.

Residue determination and dissipation of ioxynil octanoate in maize and soil.

A simple and efficient residue analysis method for direct determination of ioxynil octanoate in maize and soil was developed and validated with High Performance Liquid Chromatography-Ultra Violet (HPLC-UV). The samples were extracted with mixtures of acetonitrile and deionized water followed by Solid Phase Extraction (SPE) to remove co-extractives prior to analysis by HPLC-UV. The recoveries of ioxynil octanoate extracted from maize and soil samples ranged from 86 %-104 % and 84 %-96 %, respectively, with relative standard deviation (RSD) less than 7.84% and sensitivity of 0.01 mg kg(-1). The method was applied to determine the residue of ioxynil octanoate in maize and soil samples from experimental field. Data had shown that the dissipation rate in soil was described as pseudo-first-order kinetics and the half-life (t(1/2)) was less than 1.78 days. No ioxynil octanoate residue (<0.01 mg kg(-1)) was detected in maize at harvest time withholding period of 60 days after treatments of the pesticide. Direct confirmation of the analytes in field trial samples was realized by Liquid Chromatography-Mass Spectrometry (LC-MS).

Novel pollutants in the Moscow atmosphere in winter period: Gas chromatography-high resolution time-of-flight mass spectrometry study.

The most common mass spectrometry approach analyzing contamination of the environment deals with targeted analysis, i.e. detection and quantification of the selected (priority) pollutants. However non-targeted analysis is becoming more often the method of choice for environmental chemists. It involves implementation of modern analytical instrumentation allowing for comprehensive detection and identification of the wide variety of compounds of the environmental interest present in the sample, such as pharmaceuticals and their metabolites, musks, nanomaterials, perfluorinated compounds, hormones, disinfection by-products, flame retardants, personal care products, and many others emerging contaminants. The paper presents the results of detection and identification of previously unreported organic compounds in snow samples collected in Moscow in March 2016. The snow analysis allows evaluation of long-term air pollution in the winter period. Gas chromatography coupled to a high resolution time-of-flight mass spectrometer has enabled us with capability to detect and identify such novel analytes as iodinated compounds, polychlorinated anisoles and even Ni-containing organic complex, which are unexpected in environmental samples. Some considerations concerning the possible sources of origin of these compounds in the environment are discussed.

Noninvasive detection of cardiac sympathetic nervous dysfunction in diabetic patients using [123I]metaiodobenzylguanidine.

The association between clinical autonomic dysfunction and myocardial MIBG accumulation was investigated. The study groups comprised 6 male diabetic patients with autonomic neuropathy (ANP+ group), 6 male diabetic patients without autonomic neuropathy (ANP-group), and 6 male nondiabetic control subjects. The mean age was comparable in all groups, and the subjects had no evidence of coronary heart disease. Reduced heart-rate variation in a deep-breathing test was used as a criterion for autonomic neuropathy. Immediately after injection, the peak net influx rate of MIBG to myocardium was significantly (P less than 0.05) reduced in both diabetic groups. At 6 hr after MIBG injection, the MIBG uptake of the myocardium was significantly (P less than 0.05) smaller in the ANP+ group than in the control group. In the ANP- group, the MIBG uptake of the myocardium was between that of the ANP+ group and that of the control group. Our data show that reduced myocardial MIBG accumulation is associated with autonomic dysfunction in diabetic patients, but it can occur to a lesser extent also in diabetic patients without apparent autonomic neuropathy. The measurement of the myocardial MIBG accumulation is a promising new method to detect cardiac sympathetic nervous dysfunction in diabetic patients.

Contamination of Pantopaque by glass.

Investigation has shown that when ampules containing Pantopaque are opened, a variable amount of fragments of glass may fall into the Pantopaque. When the Pantopaque is injected into the spinal canal these fragments may also be injected. As yet the results of injecting fragments of glass into the spinal subarachnoid space are unknown. The glass can be removed by passing the Pantopaque through a 0.22 micron Millex Filter.

Movement of pendimethalin, ioxynil and soil particles to field drainage tiles.

Knowledge of the movement of herbicides and soil particles to sub-surface tile drainage may help to predict chemical leaching to surface waters and deeper groundwater systems. The movement of pendimethalin (2 years), ioxynil (1 year) and soil particles (3 years) to two tile drains was investigated on a sandy loam soil under natural weather conditions. Herbicide and particle concentrations in the drain water showed a very dynamic pattern. The largest herbicide concentrations were detected during the first tile drain flow events after application. Very little herbicide was lost with drain water later than 2 months after application. The turbidity, reflecting concentrations of soil particles, correlated positively and strongly with the pendimethalin concentration and negatively with the rate of drain water discharge, whereas it was uncorrelated with the ioxynil concentration. Peak turbidity values occurred during or shortly after rainfall events, either in break of frost situations, or on unfrozen soil coinciding with the occurrence of peak moisture contents in the topsoil well (3-7%) above field capacity. On average, 0.0013% of the applied pendimethalin and 0.0015% of the applied ioxynil were lost with drain water. The results suggest that preferential flow promotes the movement of all three substances to the tile drains but indicate somewhat different transport mechanisms for the two herbicides.

Behavior of Na131I and meta(131I) iodobenzylguanidine (MIBG) in municipal sewerage.

Behavior of 131I activity in primary sludge at the Ann Arbor, Michigan, Municipal Waste Water Treatment Plant was studied in relation to known radioiodine therapy events at the University of Michigan Hospital complex. The principal compounds administered are Na131I, which has widespread use, and meta (131I) iodobenzylguanidine (MIBG), which is a compound unique to the University of Michigan, although labeled antibodies and other forms are also used in therapy and research. The objectives of the study were to determine the environmental fate of such discharges and to determine radiation exposures to workers and the public when sludges are incinerated. Approximately 17% of the MIBG activity administered in a therapy was found in the primary sludge, whereas only 1.1% of the Na131I was in sludge. When land applied, the short half life of 131I in the sludge presents few radiological health concerns; however, incineration, which is done in winter months, is assumed to release organically bound 131I to the atmosphere. Radiation doses due to incineration of sludge containing measured concentrations were calculated for a maximally exposed worker to be 1.7 microSv (0.17 mrem) of which 0.48 microSv (0.048 mrem) was due to a 2-d upset condition. For a more typically exposed worker, and a member of the public, the committed effective dose equivalents were 1.2 microSv (0.12 mrem) and 0.06 microSv (0.006 mrem), respectively, for a 22-wk incineration period with release of all radioiodine in the sludge. Transport time to the treatment plant for radioiodine was found to be much longer than that of normal sewage, possibly due to organic material in sewer lines that absorb iodine. The residence time of radioiodine in the sewer also appears to be longer than expected; whether other radioactive materials are held up the same way is not known but chemical form is surely a factor.

[Improvement of the solubility behavior of problem drugs. 9. In vitro absorption studies using melting solidification products of iomeglamic acid]. / Beiträge zur Verbesserung des Auflösungsverhaltens von Problemarzneistoffen. 9. Mitteilung: In-vitro-Resorptionsuntersuchungen mit lomeglamsäure-Schmelzerstarrungsprodukten.

By means of the absorption apparatus according to Fürst and Neubert the solid dispersions of the iomeglamic acid were studied with regard to their in vitro absorption properties. All products showed better half lives of transport in relation to the pure compound. This was in correlation to the solubility parameters.

Enhanced competitive chemiluminescent enzyme immunoassay for the trace detection of insecticide triazophos.

A direct competitive chemiluminescent enzyme immunoassay (CLEIA) for triazophos was developed, which was based on the anti-THHe IgG monoclonal antibody and a heterogeneous enzyme tracer (THHu-HRP). Several components of chemiluminescent enhanced solution (CES) were optimized. The results showed that 1 mM of p-iodo-phenol, 0.625 mM of luminol, and 4 mM of H(2)O(2) had the best performance. Based on the study of CES, the influence of several factors (assay buffer, blocking substance, and solvent) on the immunoassay was investigated. The sensitivity for detection, IC(50) value was 0.87 ng/mL at a practical working concentration range between 0.04 ng/mL and 5 ng/mL and the limit of detection for triazophos was 0.063 ng/mL. The average recovery of triazophos added to lettuce, carrot, apple, water, and soil were 78.71%, 67.52%, 118.3%, 117.2%, and 122.0%, respectively. Finally, comparison between the methods of CLEIA and high-performance liquid chromatography-tandem mass spectrum (HPLC-MS/MS) was performed. The results obtained from CLEIA were in agreement with those of HPLC-MS/MS.