Atmospheric pressure chemical ionization mass spectrometry detection. Medical search. Frequent questions

Zhang Y, Wang Q, Zhang G, Jia W, Ren Y, Wu Y. Biomarker analysis of hemoglobin adducts of acrylamide and glycidamide enantiomers for mid-term internal exposure assessment by isotope dilution ultra-high-performance liquid chromatography tandem mass spectrometry. (cdc.gov)
A flow-injection analysis tandem mass spectrometry (FIA MSMS) method was developed for rapid quantitative analysis of 10 different inorganic and organic explosives. (mit.edu)
The eluate was concentrated, and the phthalate metabolites chromatographically resolved by reversed-phase HPLC, detected by APCI- tandem mass spectrometry (APCI-MS/MS), and quantified by isotope dilution. (cdc.gov)
Atrazine and its metabolites have been measured by high-performance liquid chromatography (HPLC) coupled with tandem mass spectrometry (HPLC-MS/MS) using atmospheric pressure chemical ionization. (cdc.gov)
Confirmation of the suspected toxicosis was obtained by detecting colchicine in serum and urine using liquid chromatography coupled with tandem mass spectrometry using atmospheric pressure chemical ionization. (uzh.ch)
La méthode est basée sur la technique d'échantillonnage direct de l'air couplée avec la spectrométrie de masse en tandem utilisant une source d'ionisation chimique à pression atmosphérique (APCI-MS/MS directe). (umontreal.ca)
In this study, a sensitive and reliable method based on an ultra-performance liquid chromatography (UPLC) couple with two ionisation modes, including electrospray ionisation (ESI) and atmospheric pressure chemical ionisation (APCI) tandem mass spectrometry (MS), namely, UPLC-ESI/APCI-MS/MS was developed and validated to simultaneously determine 8 triterpenoids (ESI mode) and 2 sesquiterpenoids (APCI mode) in RA. (hindawi.com)
Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is increasingly utilized in clinical laboratories because it has advantages in terms of specificity and sensitivity over other analytical technologies. (annlabmed.org)
They used high performance liquid chromatography with tandem mass spectrometry (LC-MS/MS) to analyse the residual enantiomers of penflufen in wheat, spinach and Chinese cabbage. (chromatographytoday.com)
Fast separation liquid chromatography-tandem mass spectrometry for the confirmation and quantitative analysis of avermectin residues in food. (ata-journal.org)
Analysis of avermectin and moxidectin residues in milk by liquid chromatography-tandem mass spectrometry using an atmospheric pressure chemical ionization/atmospheric pressure photoionization source. (ata-journal.org)
Pozo OJ, Marin JM, Sancho JV, Hernandez F. Determination of abamectin and azadirachtin residues in orange samples by liquid chromatography-electrospray tandem mass spectrometry. (ata-journal.org)
Grimalt S, Pozo ÓJ, Marín JM, Sancho JV, Hernández F. Evaluation of different quantitative approaches for the determination of noneasily ionizable molecules by different atmospheric pressure interfaces used in liquid chromatography-tandem mass spectrometry: abamectin as case of study. (ata-journal.org)
Rübensam G, Barreto F, Barcellos Hoff R, Mara Pizzolato T. Determination of avermectin and milbemycin residues in bovine muscle by liquid chromatography-tandem mass spectrometry and fluorescence detection using solvent extraction and low temperature cleanup. (ata-journal.org)
Accurate DESI and DAPCI tandem mass spectra were obtained and these greatly enhance the selectivity and information content of the experiment. (warwick.ac.uk)
Mass spectrometry is an analysis method that can be performed once using a single analyzer, or it can be performed in tandem between different mass analyzers (such as those found in hybrid or tribrid mass spectrometers). (thermofisher.com)
The practice of simultaneous MS is frequently termed tandem mass spectrometry (MS/MS or MS 2 ) and refers to two or more reaction steps being performed on selected ions. (thermofisher.com)
Tandem mass spectrometry is a method to further enhance the specificity of mass spectrometry. (myadlm.org)
Title : A Candidate Reference Measurement Procedure for Quantifying Serum Concentrations of 25-Hydroxyvitamin D3 and 25-Hydroxyvitamin D2 Using Isotope-Dilution Liquid Chromatography-Tandem Mass Spectrometry Personal Author(s) : Mineva, Ekaterina M.;Schleicher, Rosemary L.;Chaudhary-Webb, Madhulika;Maw, Khin L.;Botelho, Julianne C.;Vesper, Hubert W.;Pfeiffer, Christine M. (cdc.gov)
Third trimester archived spot urine samples were analyzed by online solid phase extraction coupled with high performance liquid chromatography isotope dilution tandem mass spectrometry. (biomedcentral.com)

Conifer seed oils from European Larch (Larix decidua), Norway Spruce (Picea abies) and European Silver Fir (Abies alba) have been analyzed by non-aqueous reversed-phase high-performance liquid chromatography (NARP-HPLC) with atmospheric pressure chemical ionisation (APCI)-MS detection. (unboundmedicine.com)
TGs containing Delta5-UPIFAs have a higher retention in comparison with common TGs found in plant oils with single methylene interrupted Delta6(9)-FAs and also significantly changed relative abundances of fragment ions in APCI mass spectra. (unboundmedicine.com)
Performance is optimized by tailoring the ionization method (APCI/ESI), de-clustering potentials, and collision energies for each specific analyte. (mit.edu)
Both mercury chloride and mercury bromide have been sporadically detected in Montreal urban and indoor air using atmospheric pressure chemical ionization-mass spectrometry (APCI-MS). We discuss limitations and advantages of the current technique and discuss potential avenues for future research including quantitative trace measurements of a larger range of mercury compounds. (nih.gov)
Two types of ionization sources have emerged as the most commonly used to couple LC to MS: atmospheric pressure chemical ionization (APCI) and electrospray ionization (ESI). (usda.gov)
It was demonstrated that substituted indoles fully labelled with deuterium on the aromatic ring can undergo substantial exchange back to partial and even fully protonated forms during Atmospheric Pressure Chemical Ionisation (APCI) LC-MS. The degree of this exchange was strongly dependent on the absolute quantity of analyte, the APCI desolvation temperature, the nature of the mobile phase, the mobile phase flow rate and the instrument used. (edu.au)
In the realm of mass spectrometry, I focus on soft ionization processes, such as electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI), for detection of moderately polar and nonpolar analytes. (rutgers.edu)
Packed-column supercritical fluid chromatography (pSFC) using ultra-violet (UV) and atmospheric pressure chemical ionisation (APCI) mass spectrometry (MS) provides a versatile method for the identification and quantification of β-agonists. (nottingham.edu.cn)
Example ionization methods include atmospheric pressure chemical ionization (APCI) , electron ionization (EI), electrospray ionization (ESI) , chemical ionization (CI) inductively coupled plasma (ICP) ionization, and matrix-assisted laser desorption/ionization (MALDI). (thermofisher.com)
He compared electrospray ionisation (ESI) source, thermally focused/heated electrospray (HESI), atmospheric pressure photoionisation (APPI) source with and without dopant, and multimode source in ESI mode, atmospheric pressure chemical ionisation (APCI) mode, and combined mode using both ESI and APCI, i.e. altogether seven different ionisation modes for the analysis of 40 pesticides (see list below). (ut.ee)
The past decade has witnessed resurgent interest in coupling GC to atmospheric pressure chemical ionization (APCI), which requires high gas flows to assist ionization. (chromatographyonline.com)

His High-performance liquid chromatography, Gas chromatography, Detection limit, Extraction and Sample preparation study are his primary interests in Chromatography. (research.com)
The most common form of liquid chromatography in use today is high-performance liquid chromatography (HPLC), which pumps the sample mixture through the column at high pressure. (europeanpharmaceuticalreview.com)
Pinheiro-Sant'Ana HM, Guinazi M, Oliveira DS, Della Lucia CM, Reis BDL, Brandão SCC (2011) Method for simultaneous analysis of eight vitamin E isomers in various foods by high performance liquid chromatography and fluorescence detection. (springer.com)

1997. Comparison of gas chromatography and immunoassay methods for the detection of atrazine in water and soil. (cdc.gov)
Liquid chromatography (LC) coupled to mass spectrometry (MS) has become the method of choice for analysis of complex lipid samples. (usda.gov)
Gas chromatography-mass spectrometry (GC-MS) was used in the qualitative analysis of RA for the volatile oil, containing sesquiterpenoids [ 25 ]. (hindawi.com)
His primary areas of investigation include Environmental chemistry, Chromatography, Mass spectrometry, Perfluorooctanoic acid and Perfluorooctane. (research.com)
The identity confirmation of the analyte was carried out using liquid chromatography coupled to mass spectrometry, with atmospheric pressure chemical ionization. (unicamp.br)
However, some components may have weak UV chromophores if UV detection is being used or be completely retained on the liquid chromatography column. (europeanpharmaceuticalreview.com)
1]. M. J. Lerma-Garcia, E. F. Simo-Alfonso, A. Mendez, J. L. Liberia and Jose Manuel Herrero-Marinez, "Fast separation and determination of sterols in vegetable oil by ultraperformance liquid chromatography with atmospheric pressure chemical ionization mass spectrometry detection", Journal of Agriculture and Food Chemistry, vol. 58, p. 2771-2776, 2010. (gov.vn)
Conﬁ rmatory techniques are largely based on mass spectrometry (MS) with an emphasis on Liquid Chromatography-Mass Spectrometry (LC-MS), due to low sample volumes and the low detection limits required. (nomedicalcare.com)
Valenzuela AI, Redondo MJ, Pico Y, Font G. Determination of abamectin in citrus fruits by liquid chromatography-electrospray ionization mass spectrometry. (ata-journal.org)
Some proposals were additionally made to address the very common, significant research gaps noted in CECs research, especially the standardization of analytical chemical test methods, based on chromatography-mass spectrometry, for quantification. (openaccesspub.org)
If gas chromatography is used, the analyte is already in the gas phase and an electron ionization source is used to generate a charged analyte. (myadlm.org)
The 14 analytes, separated within 4.15 min using reversed-phase liquid chromatography, were determined using a triple-quadrupole mass spectrometer with atmospheric-pressure chemical ionization and multiple reaction monitoring in negative and positive ionization modes. (cdc.gov)
Choosing the best possible ion source is a very important step in liquid chromatography mass spectrometry (LC/MS) method development. (ut.ee)
The metabolomics workflow described here combines untargeted (discovery) quadrupole time-of-flight (Q-TOF) liquid chromatography-mass spectrometry (LC-MS), targeted (confirmation) triple-quadrupole LC-MS-MS, and sophisticated data mining as an effective means to elucidate metabolite changes. (spectroscopyonline.com)
This study describes metabolomic changes that occur due to malaria infection and demonstrates the utility of a combined untargeted (discovery) liquid chromatography-mass spectrometry (LC-MS) and targeted (confirmation) LC-MS-MS workflow. (spectroscopyonline.com)
The Quantitative Measurement of Peptidoglycan Components Obtained from Acidic Hydrolysis in Gram-Positive and Gram-Negative Bacteria via Hydrophilic Interaction Liquid Chromatography Coupled with Mass Spectrometr. (tftak.eu)
Quantitative Analysis of Oat (Avena sativa L.) and Pea (Pisum sativum L.) Saponins in Plant-Based Food Products by Hydrophilic Interaction Liquid Chromatography Coupled with Mass Spectrometry. (tftak.eu)
The Column spoke to Katherine Curran, a lecturer in Sustainable Heritage at the UCL Institute for Sustainable Heritage in London, UK, about her work classifying museum artefacts using volatile organic compound (VOC) analysis and solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). (chromatographyonline.com)

Secondary electrospray ionization mass spectrometry (SESI-MS) enables the detection of volatile organic compounds (VOCs) without the need for any sample pretreatment. (jove.com)
SESI ionization occurs by proton transfer reactions between the electrospray solution and the volatile analyte, and is therefore suitable for the analysis of hetero-organic molecules, just as in traditional electrospray ionization (ESI). (jove.com)
Wilm, M (2011) Principles of electrospray ionization. (thermofisher.com)
For analytes introduced into the mass spectrometer as a liquid, several types of sources exist including electrospray ionization and atmospheric pressure chemical ionization. (myadlm.org)

A variety of mass spectrometer types, including magnetic sector, quadrupole, time-of-flight, and ion trap, have and will continue to deepen our understanding of the formation and evolution of exploration targets like the surfaces and atmospheres of planets and their moons. (frontiersin.org)
Once ionized, the volatiles are pulled into the mass spectrometer for analysis (4). (jove.com)
Choose the appropriate vessel for growing your cultures, considering the growth requirements of the species in your experiment (e.g., aeration, light, temperature, etc.), as well as the efficient delivery of volatiles to the mass spectrometer. (jove.com)
Once separated by LC, the amino acids enter the mass spectrometer for detection and quantification. (pharmiweb.com)
The mass spectrometer ionizes the derivatized amino acids, generating charged ions that are subsequently analyzed based on their mass-to-charge ratio (m/z). (pharmiweb.com)
The output from each of the liquid chromatographs is sent to a mass spectrometer for detection. (usda.gov)
Unfortunately, the duty cycle of the mass spectrometer is finite, which limits the number of experiments that can be performed in a single run. (usda.gov)
Specifically, I will show how microsolvated phases, or small clusters of solute and solvent, can change what species enter the mass spectrometer. (rutgers.edu)
the chromatograph is attached via an interface to a mass spectrometer. (europeanpharmaceuticalreview.com)
Atoms and molecules must first be ionized before they can be accelerated through the mass spectrometer and detected. (thermofisher.com)
The heart of the mass spectrometer is its mass analyzer. (thermofisher.com)
Samples must be ionized (or charged) before they can be manipulated by electric and magnetic fields within the mass spectrometer. (thermofisher.com)
In general, an assay that uses a mass spectrometer as the final detection method will involve a sample preparation step, a chromatographic separation and measurement with a mass spectrometer. (myadlm.org)
The final stage of detection using a mass spectrometer is the focus of this portion of Pearls of Laboratory Medicine. (myadlm.org)
With the mass of our analyte known, we need to decide what type of mass spectrometer to use for analysis. (myadlm.org)
Although every type of mass spectrometer uses the same charged ions, how it separates individual analytes varies greatly. (myadlm.org)
How long the mass spectrometer sits at a voltage and frequency combination is called the dwell time, during which only a limited number of ions are successfully reaching the detector. (myadlm.org)

Modern flight-capable mass spectrometers, in combination with various sample processing, separation, and ionization techniques enable sensitive detection of chemical biosignatures. (frontiersin.org)
This book chapter describes numerous ways in which multiple instruments that measure the masses of molecules (mass spectrometers) can be used in parallel to provide much more information about samples than single instruments used alone. (usda.gov)
The techniques discussed include 'dual parallel mass spectrometry' in which two mass spectrometers are used in parallel, and 'triple parallel mass spectrometry' in which three mass spectrometers, operating in different modes, are used in parallel. (usda.gov)
The data demonstrate how the shortcomings of any single instrument are overcome by employing mass spectrometers that acquire complementary data from the same analytes, and demonstrate that such an arrangement provides a greater degree of confidence in both qualitative and quantitative results. (usda.gov)
This is because mass spectrometers separate particles by calculating their different mass-to-charge ratios (m/z). (thermofisher.com)
Different analyzers are also combined in hybrid and tribrid mass spectrometers. (thermofisher.com)
The general operation of mass spectrometers, including hybrid and tribrid mass spectrometers. (thermofisher.com)
Topics for discussion will include ionization methods, the different types of mass spectrometers used clinically, different methods of analysis, and highlight some future areas where mass spectrometry will most likely be applied. (myadlm.org)
Single quadrupole and triple quadrupole mass analyzers are the most common mass spectrometers found in the clinical laboratory, but it's important to recognize that laboratories are also using time of flight analyzers for specific applications. (myadlm.org)
Differential flow modulation is a simple and cost-effective alternative to thermal modulation, but the requisite high flow rates are generally perceived as being incompatible with most (electron ionization [EI] and chemical ionization [CI]) mass spectrometers. (chromatographyonline.com)

This selective method allows for rapid detection of seven metabolites of commonly used dialkyl phthalates in human urine with limits of detection in the low parts per billion (ppb) range. (cdc.gov)
Zettner MA, Flor S, Ludewig G, Wagner J, Robertson LW, Lehmann L. Quinoid metabolites of 4-monochlorobiphenyl induce gene mutations in cultured Chinese hamster v79 cells. (who.int)
The detection from human skin of the active ingredients from ointments is reported together with the detection of ibuprofen metabolites in human urine. (warwick.ac.uk)
One of the key challenges in metabolomics is the unraveling of the complex sets of data, which can include many experimental artifacts, and it is compounded by the tremendous chemical diversity of metabolites (1). (spectroscopyonline.com)

It is commonly used for the identification of organic compounds from electron ionization mass spectrometry. (wikipedia.org)
Electron ionization uses a beam of electrons that interact with molecules to form radical cations, which in turn often undergo fragmentation in the source to more stable species. (myadlm.org)

We demonstrate that the AP-ID-CIMS allows quantification of sulfuric acid concentrations and is capable of detecting gaseous sulfuric acid with a detection limit of less than 10(5) molecules cm(-3), on the basis of 3sigma of the baseline noise and an integration time of 12 s. (tamu.edu)
Allows identification and quantification of amino acids by measuring their mass-to-charge ratio. (pharmiweb.com)
The column separates the amino acids based on their hydrophobicity, allowing for their individual detection and quantification. (pharmiweb.com)
The limits of detection and quantification for analytes were 0.14-1.67 ng/mL and 0.44-5.65 ng/mL, respectively. (hindawi.com)
The method was validated and the following parameters were established: linearity (0.9999), linear range (0.04% to 12.8% m/m), intra-day precision (4.8%, n=7) and inter-day precision (5.2%, n=10), detection limit (0.01% m/m) and quantification limit (0.04% m/m). (unicamp.br)
Cunha SC, Amaral JS, Fernandes JO, Oliveira MBPP (2006) Quantification of tocopherols and tocotrienols in Portuguese olive oil using HPLC with three different detection systems. (springer.com)

Combining mass spectrometry with separation techniques such as HPLC or CE can improve the accuracy and sensitivity of amino acid analysis. (pharmiweb.com)
Mass spectrometry has four essential functions, which are ionization, separation (filtering), detection and analysis. (thermofisher.com)
Metabolomics workflows typically include several steps: sample preparation, chromatographic separation, mass spectrometry detection of ions, data file analysis, compound finding, multiple data file alignment, statistical analyses of the different conditions (variables), and compound identification. (spectroscopyonline.com)

Operation of the drift tube at atmospheric pressure allows a significantly longer ion-molecule reaction time and eliminates dilution of the ambient samples, while a well-defined electric field inside the drift tube provides the benefits to confine the flight path and velocity of reagent/product ions, to break down ion clusters, and to control the ion-molecule reaction time. (tamu.edu)
Mass spectral interpretation is the method employed to identify the chemical formula, characteristic fragment patterns and possible fragment ions from the mass spectra. (wikipedia.org)
These peaks result from ions with lifetimes shorter than the time needed to traverse the distance between ionization chamber and the detector. (wikipedia.org)
In the first step of mass analysis, precursor ions are formed in the ion source and induced to fragment. (thermofisher.com)
Learn more about how mass analyzers separate, select and even fragment ions based on their distinct masses and charges. (thermofisher.com)
Once we have a way to get ions charged and into the gas phase, the most important aspect in the analysis is the mass-to-charge ratio, designated as m over z. (myadlm.org)
Since all ions are being accelerated by the same electric field, ions with a low mass-to-charge ratio will accelerate faster than ions with a high mass-to-charge ratio. (myadlm.org)
How long it takes a given ion to travel down the flight tube is how ions of different mass-to-charge ratios are distinguished. (myadlm.org)

We detail here the development of a soft ionization mass spectrometric technique coupled with preconcentration onto nano- or microparticle-based traps prior to analysis for the measurement of mercury halides in air. (nih.gov)

Metabolomics is therefore the systematic study of the unique chemical fingerprints that specific cellular processes produce, and it can provide an instantaneous snapshot of the physiology of that biological system. (spectroscopyonline.com)
Metabolomics, a word coined in 1998, is the study of small molecules (that is, organic chemicals with a molecular weight of 50-2000 Daltons) present in a given biological fluid, tissue, organ, organism, and environment at a given time. (chromatographyonline.com)
Using the power and high throughput of analytical platforms, such as mass spectrometry (MS) or nuclear magnetic resonance (NMR) spectroscopy, metabolomics promises to be a cornerstone in innovations and discoveries in the areas of medicine, agriculture, biomedical, space, and environment. (chromatographyonline.com)

Pesticides in water: Liquid chromatographic method with ultraviolet detection 992.14. (cdc.gov)

This method has limits of detection ranging from 20 to 500 ng/l (parts per trillion) and relative standard deviations of less than 11 % (Baker, et al. (cdc.gov)
The lowest limits of detection (LoDs) were obtained by ESI and HESI. (ut.ee)

HPLC can be combined with various detection methods, such as UV absorption or fluorescence, to improve the accuracy of the analysis. (pharmiweb.com)
Determination of abamectin and doramectin in sheep faeces using HPLC with fluorescence detection. (ata-journal.org)
A multiresidue method for the determination of abamectin, doramectin, moxidectin, ivermectin, milbemectin A3, and milbemectin A4 residues in bovine muscle using HPLC with fluorescence detection. (ata-journal.org)
Only appropriate dilution of samples with 2-propanol was necessary for their direct analysis by a multicommuted flow injection (MCFIA) manifold based on three solenoid valves with fluorescence detection. (springer.com)

Organic chemists obtain mass spectra of chemical compounds as part of structure elucidation and the analysis is part of many organic chemistry curricula. (wikipedia.org)
Examining organic compounds, the relative intensity of the molecular ion peak diminishes with branching and with increasing mass in a homologous series. (wikipedia.org)
For compounds of moderate to low polarity DAPCI produced more effective ionisation. (warwick.ac.uk)
Saturation vapor pressure ( p sat ) is an important thermodynamic property regulating the gas-to-particle partitioning of organic compounds in the atmosphere. (copernicus.org)

In recent years, charged aerosol detection (CAD) has become a valuable tool for fast and efficient quantitative chromatographic analysis of drug substances with weak UV absorption. (chromacademy.com)

In order for an analyte to be measured using mass spectrometry it must carry a charge and be in the gas phase. (myadlm.org)
An analyte with a molecular weight of 415 and a charge of +1 will have a mass-to-charge ratio of 415. (myadlm.org)
For an analyte at a known mass-to-charge ratio, the amount of positive or negative charge and the frequency at which the diagonal pairs switch their sign is optimized to produce a successful ion flight path through the quadrupole. (myadlm.org)

10%) method for trace explosive detection that can play an important role in criminal and attributional forensics, counterterrorism, and environmental protection areas, and has the potential to augment or replace several of the existing explosive detection methods. (mit.edu)
Application of this method to the National Health and Nutrition Examination Survey (NHANES) project will help determine the concentration range of these chemicals in residents in the United States. (cdc.gov)
The method was first described by Fenn and colleagues 1 and has been applied to the detection of illicit drugs 2 and explosives 3-4 , the characterization of skin volatiles 5 , and the analysis of breath 6-7 . (jove.com)
We are expanding the use of SESI-MS to the detection of bacterial volatiles as a method for bacterial identification and characterization 8 . (jove.com)
the most sensitive method for HPLC detection is reductive electrochemical detection, which has yielded excellent results in the investigation on some classes of drugs. (europeanpharmaceuticalreview.com)
We also have a single method for heavy metals with our inductively coupled plasma mass spectrometry system (ICP-MS). (technologynetworks.com)
The method includes automated solid-phase extraction using customized positive-pressure functions. (cdc.gov)

Finally, we tested urine samples from 90 smokers and observed detection rates of over 98% for six analytes with urinary HCTF and MEG concentrations ranging from 200-14,100 and 60-57,100 ng/mL, respectively. (cdc.gov)

The AP-ID-CIMS exhibits advantages over the conventional low pressure ID-CIMS and flow tube AP-CIMS, improving the detection sensitivity by 3 orders of magnitude and a factor of 3, respectively. (tamu.edu)
TOF analyzers have essentially an unlimited mass-to-charge range, very high sensitivity, very high mass accuracy, high transmission percentage but a limited dynamic range. (myadlm.org)
Quadrupoles have a limited mass-to- charge range, high sensitivity, high mass accuracy, but a low ion transmission percentage. (myadlm.org)

Mass spectra is a plot of relative abundance against mass-to-charge ratio. (wikipedia.org)

Due to the high vacuum pressure in the ionization chamber, the mean free path of molecules are varying from 10 cm to 1 km and then the fragmentations are unimolecular processes. (wikipedia.org)
The nitrogen rule states that organic molecules that contain hydrogen, carbon, nitrogen, oxygen, silicon, phosphorus, sulfur, or the halogens have an odd nominal mass if they have an odd number of nitrogen atoms or an even mass if they have an even number of nitrogen atoms are present. (wikipedia.org)
But nature is chiral in many respects, it uses only the left- or right-handed molecules, especially in its chemical reactions. (chromatographytoday.com)

In This Edition Modern & Practocal Applications - Accelerating ADC Development with Mass Spectrometry - Implementing High-Resolution Ion Mobility into Peptide Mapping Workflows Chromatogr. (chromatographytoday.com)
Access our extensive collection of mass spectrometry workflows, scientific applications, technical handbooks, webinars and more. (thermofisher.com)

the utility of Mass Tag PCR was increasingly important to clinical management and determined in blinded analysis of previously diagnosed public health. (cdc.gov)
Tradespace analysis is performed for two popular standoff detection methods: longwave infrared hyperspectral imaging and deep-UV Raman spectroscopy. (mit.edu)
Some classes of lipids are more amenable to analysis by one type of ionization versus another, and the optimal conditions for each vary, such as gas flow, temperature, and voltage. (usda.gov)
This observation has major implications for quantitative assays using deuterium labelled internal standards and for the detection of deuterium labelled products from isotopically labelled feeding experiments where there is a risk of back exchange to the protonated form during the analysis. (edu.au)
Analysis of milk samples 'spiked' with β-agonists showed that the matrix caused no interference, with detection limits of approximately 500 μg l -1 of β-agonists. (nottingham.edu.cn)
Three ionisation techniques that require no sample preparation or extraction prior to mass analysis have been used for the rapid analysis of pharmaceutical tablets and ointments. (warwick.ac.uk)
These methods were M the novel direct analysis in real time (DART), (ii) desorption electrospray ionisation (DESI), and (iii) desorption atmospheric pressure chemical ionisation (DAPCI). (warwick.ac.uk)
The different approaches to sample labeling and mass spectrometry analysis. (thermofisher.com)
The results that are generated by implementing these algorithms are subsequently imported into Mass Profiler (MP) or Mass Profiler Pro (MPP) data analysis software (Agilent Technologies, Santa, Clara, California) for data filtering, statistical analysis, and visualization of results. (spectroscopyonline.com)
All the result files generated by the different analytical platforms can be imported into Mass Profiler Pro (MPP) for statistical analysis and visualization. (spectroscopyonline.com)

The amino acids are eluted in a specific order and their concentration can be determined by various detection methods. (pharmiweb.com)

For the detection of the components, a diode array and rapid scanning detector are useful for peak identification and for the monitoring of peak purity. (europeanpharmaceuticalreview.com)
These functions are coordinated by the following components: the ion source, mass analyzer, detector and software. (thermofisher.com)

The current methodology has comparable detection limits (4-11 pg m(-3)) to previously developed techniques for the measurement of total inorganic mercury in air while allowing for the identification of HgX2 in collected samples. (nih.gov)

Angelo, H. R. and Kaa, E. [Detection of morphine after ingestion of poppy seeds]. (webmd.com)

In recent years, the frequent detection of ATZ and its degradation products in water supplies and concerns about ATZ potential endocrine/reproductive and neurological effects in wildlife and humans triggered several environmental and epidemiologic studies for assessment of possible human health hazards of ATZ and other triazine pesticides [1-3]. (cdc.gov)

HPLC-UV uses UV as a form of detection. (europeanpharmaceuticalreview.com)

The multiplexed FMCAs presented herein have substantial benefits over classical chemical and traditional EUSA methods. (cdc.gov)
IEC, HPLC or CE) and detection methods described above to identify and quantify amino acids in protein samples. (pharmiweb.com)
Various methods such as sonication, heat treatment, or chemical denaturants can be employed. (pharmiweb.com)
In this talk, I will discuss two specific examples, one in the field of catalysis and one related to mass spectrometry, as showcases of the power of computational methods in interpreting, predicting and designing selective and efficient chemical processes. (rutgers.edu)

The various options for sample ionization using different ion sources. (thermofisher.com)

Amino acids are generally not very amenable to direct detection by LC-MS due to their low ionization efficiency. (pharmiweb.com)

PAHs constitute a group of chemicals, which are formed during the incomplete combustion of coal, oil and gas, garbage, and other organic substances. (cdc.gov)
Atmospheric ozone can induce artefacts in volatile organic compound measurements. (copernicus.org)
The volatility of an organic compound can be quantified by its saturation vapor pressure ( p sat ) which is the key thermodynamic property describing the equilibrium gas-particle partitioning of the compound (Pankow, 1994). (copernicus.org)

Remote sensing of atmospheric gases improves our understanding of the state and evolution of the Earth's environment. (uwaterloo.ca)

Le benzène en particulier est classé cancérogène et une exposition à des concentrations supérieures à 64 g/m3 de benzène peut être fatale en 5-10 minutes. (umontreal.ca)

The differences between commonly used mass analyzers. (thermofisher.com)

This security gap could be filled by standoff chemical sensors that detect IEDs based on external trace explosive residues. (mit.edu)
Crucially, the physical morphology of trace explosive residues and chemical "clutter" present unique challenges to the operational performance of standoff sensors. (mit.edu)

Bozan, B. and Temelli, F. Chemical composition and oxidative stability of flax, safflower and poppy seed and seed oils. (webmd.com)

The energy of the electron beam is typically 70 electronvolts and the ionization process typically produces extensive fragmentation of the chemical bonds of the molecule. (wikipedia.org)
The collection with drug testing in oral ﬂ uid,8 and detection times and time is typically one to three minutes, however this can vary as pharmacokinetics of selected drugs.9,10 discussed earlier. (nomedicalcare.com)

Organisms1

Chemicals and Drugs8

Analytical, Diagnostic and Therapeutic Techniques and Equipment13

Phenomena and Processes7

Disciplines and Occupations1

Health Care6

Tandem20

APCI11

High-performance li3

Chromatography18

Electrospray ionization4

Spectrometer17

Spectrometers10

Metabolites4

Electron ionization2

Quantification6

Separation3

Ions8

Spectrometric1

Metabolomics3

Liquid1

Limits of detection2

Fluorescence4

Compounds4

Chromatographic1

Analyte3

Method7

Urine1

Sensitivity3

Spectra1

Molecules3

Workflows2

Analysis10

Concentration1

Detector2

Methodology1

Morphine1

Pesticides1

HPLC-UV1

Methods4

Sample1

Efficiency1

Organic3

Improves1

Concentrations1

Commonly1

Residues2

Composition1

Typically2