A novel chemical ionization source for organic mass spectrometry is introduced. This new uses a glow discharge in the flowing afterglow mode generation of excited species and ions. The direct-current gas operated helium at atmospheric pressure; typical operating voltages currents are around 500 V 25 mA, respectively. generated by this pressure mixed with ambient air to generate reagent ions (mostly ionized water clusters NO+), which then used gaseous compounds. wide variety substances, both...

A novel method based on ultrasound-assisted EESI-MS has been developed and applied to rapidly detect the presence of melamine in raw milk, wheat gluten milk powder with no or minor sample pre-treatment; high throughput figures merit make it specially useful for screening levels well below current safety limit various food matrices.

The flowing afterglow-atmospheric pressure glow discharge (APGD) ionization source described in part 1 of this study (in issue) is applied to the direct analysis condensed-phase samples. When either liquids or solids are exposed ionizing beam APGD, strong signals for molecular ions substances present on their surfaces can be detected without compromising integrity solid sample structure substrate. As was observed gas-phase compounds study, both polar and nonpolar ionized by mass...

A glow discharge using a solution as the cathode was investigated to add understanding of operating mechanism and characteristics such systems. The intensities vertical distributions emission from several analytes background species were observed compared with distribution Fe excitation OH rotational temperatures, well electrical characteristics. effects gap size, pH conductivity solution, applied current flow rate on these also studied. Detection limits for this system found be comparable...

The fractional quantum Hall (FQH) effect at filling factor ν = 5/2 has recently come under close scrutiny, as its ground state may possess quasi-particle excitations obeying nonabelian statistics, a property sought for topologically protected operations. However, microscopic origin remains unknown, and candidate model wave functions include those with undesirable abelian statistics. We report direct measurements of the electron spin polarization FQH using resistively detected nuclear...

A novel direct current glow discharge sustained in helium at atmospheric pressure has been developed. Current–voltage behavior and spectroscopic characteristics strongly suggest that the system operates regime, spite of high pressure. The diffuse extremely stable is typically operated within a voltage range 300–900 volts (in current-controlled mode) currents ranging over tens to hundreds milliamps. Spatially resolved measurements some selected species are presented. Rotational temperature...

Previously performed studies have shown that alfalfa shoot biomass can bind an appreciable amount of nickel(II) and chromium(III) ions from aqueous solution. Direct indirect approaches were applied to study the possible mechanisms involved in metal binding by biomass. The direct approach involves investigations metal-bound X-ray absorption spectroscopic analysis (XANES EXAFS). Results these suggest mostly occurs through coordination with oxygen ligands. Indirect consist chemical modification...

Flowing afterglow atmospheric pressure glow discharge tandem mass spectrometry (APGD-MS/MS) is used for the analysis of trace amounts pesticides in fruit juices and on peel. The APGD source was rebuilt after Andrade et al. (Andrade al., Anal. Chem. 2008; 80: 2646-2653; 2654-2663) mounted onto a hybrid quadrupole time-of-flight spectrometer. Apple, cranberry, grape orange as well peel salad leaves were spiked with aqueous solutions containing alachlor, atrazine, carbendazim, carbofuran,...

Extractive electrospray ionization mass spectrometry (EESI-MS) was applied to rapid fingerprinting of various perfumes for quality classification. Unique EESI-MS fingerprints ten famous brands were obtained. This technique shown be applicable forgery detection on the example an authentic and a counterfeit 'Miss Dior' fragrance by Christian Dior. We believe that high throughput simplicity this sample-preparation-free method can advantageous in perfume industry, instance when online control.

Extractive electrospray ionization mass spectrometry is shown to allow real-time, in vivodrug monitoring and pharmacokinetic measurement a non-invasive, pain-free manner as demonstrated by the spectral of novel exhaled breath biomarker for valproic acid, medication used control epilepsy.

We report herein the use of Medicago sativa alfalfa shoot biomass for removal gold from aqueous solutions. The accumulation process involves reduction Au(III) to colloidal Au(0) and is shown increase at elevated temperatures lower pH. X-ray absorption spectroscopy (XAS) was used determine that gold(III) reduced form gold(0) colloids, which varied in size depending on pH initial solution. cluster radius 6.2 ± 1 Å 5 9.0 2. Our findings indicate essentially another layer atoms deposited onto...

Extractive electrospray ionization mass spectrometry (EESI-MS) for real-time monitoring of organic chemical reactions was demonstrated a well-established pharmaceutical process reaction and widely used acetylation in the presence nucleophilic catalyst, 4-dimethylaminopyridine (4-DMAP). EESI-MS provides information that allows us to determine optimum time terminating based on relative intensities precursors products. In addition, tandem spectrometric (MS/MS) analysis via permits on-line...

We report the observation of a fully developed fractional quantum Hall state at $\nu=5/2$ in GaAs/Al$_{x}$Ga$_{1-x}$As wells with mobility well below $10^{7}$\thinspace cm$^{2}$/Vs. This is achieved either by strong illumination or reducing barrier Al composition without illumination. explain both results terms screening ionized remote impurity (RI) potential nearby neutral shallow donors. Despite dramatic improvement transport features, energy gap $\Delta_{5/2}$ limited to rather small...

Glow discharge optical emission spectrometry (GDOES) allows fast and simultaneous multielemental analysis directly from solids depth profiling down to the nanometer scale, which is critical for thin-film (TF) characterization. Nevertheless, operating conditions best limits of detection (LODs) are compromised in lieu sputtering crater shapes resolution. In addition, transient signals ultra-TFs do not permit optimal sampling statistics bulk such that LODs further compromised. Furthermore,...

The ion and electron populations of a glow discharge that uses an electrolytic solution as the cathode (an electrolyte-cathode or ELCAD) were investigated. This paper presents first determinations number density, ionization temperature, degrees in ELCAD. Spectroscopic techniques used to keep from perturbing plasma, range conditions was explored, two regions (the negative positive column) observed. By using Stark broadening hydrogen beta line, densities near 8.5 × 1014 cm−3 for 2.5 column...

Recent findings suggest that long-term exposure to diethyl phthalate (DEP), one of the widely used esters, can lead serious health problems. Most perfumes contain non-negligible amounts DEP. Rapid and sensitive detection DEP in is thus increasing importance. A novel procedure based on extractive electrospray ionization mass spectrometry (EESI-MS) has been developed for fast identification without need any sample pretreatment. The limit determination perfume was less than 100 ppb using tandem...

An instrument that combines near-field laser ablation at atmospheric pressure with an ion trap/time-of-flight mass spectrometer was developed. By coupling a UV into fiber tip of scanning optical microscope, craters much smaller than achievable conventional optics can in principle be obtained. Laser performed on samples such as DHB, anthracene, and pyrene. Desorbed neutral analytes are transferred from to trap, ionized, stored. After 10 ms, the ions extracted sensitive time-of-flight...

Sticky subject: An N2 stream forms bubbles inside bulk viscous liquids, which create an aerosol sample through a microjetting mechanism (see picture). This is then analyzed by extractive electrospray ionization (EESI) mass spectrometry (MS). EESI-MS reveals the molecular composition of complex liquids and kinetics ongoing processes occurring in highly without any pretreatment. Detailed facts importance to specialist readers are published as "Supporting Information". Such documents...

Fluorescence spectroscopy and mass spectrometry have been extensively used for characterization of biomaterials, but usually separately. An instrument combining fluorescence Fourier-transform ion cyclotron resonance (FTICR-MS) has developed to explore both spectrometric behavior ions produced by electrospray ionization (ESI) in ultra high vacuum (<5 × 10−9 mbar). Using rhodamine 6G (R6G) as a sample, the was systematically characterized. Gas-phase spectral signal same population are detected...

Flowing afterglow atmospheric pressure glow discharge mass spectrometry (FA-APGD-MS) was used to interrogate different polymer species such as biopolymers, synthetic homo- and co-polymers. The main advantages of FA-APGD-MS for samples include speed (<30 s per sample) analysis at pressures. Moreover, there are essentially no restrictions the kind sample that can be analyzed because deal with liquid solid (soluble or insoluble) bulk polymers granulates, irrespective their conductivity, without...