spectrometry

Enflurane (Efrane), a volatile anaesthetic, is a potent inhibitor of high conductance Ca2+-activated K+ channels of Chara australis. Enflurane is an internal standard in monitoring halogenated volatile anaesthetics by headspace gas chromatography-mass spectrometry. It allows rapid adjustments of anesthesia depth with little change in pulse or respiratory rate.

Dimetridazole is a nitroimidazole-based compound with antibacterial and anticoccidial activity. It was once widely used in the treatment of parasitic infections in poultry, cattle, swine and farmed fish until suspected to be carcinogenic and mutagenic to humans. Hydroxy dimetridazole is a metabolite of dimetridazole that may be useful for identifying this nitroimidazole in various agricultural samples through liquid chromatography-tandem mass spectrometry and other methods.

6-Hydroxynicotinic acid (6-Hydroxypyridine-3-carboxylic acid) is exploited in the use of NMR spectroscopy or gas chromatography--mass spectrometry for the diagnosis of Pseudomonas aeruginosa in urinary tract infection. Among the common bacteria causing urinary infection, only P. aeruginosa produces 6-hydroxynicotinic acid from nicotinic acid.

α-Cyano-4-hydroxycinnamic acid (α-CHCA) is an inhibitor of monocarboxylate transporter 1 (MCT1), which blocks pyruvate transport in rat heart mitochondria (IC50: 1.5 μM).

1-Thioglycerol (alpha-Thioglycerol) is an antioxidant thioglycerol that scavenges free radicals and reduces oxidative stress as a media component, and is used as a matrix in fast atom bombardment mass spectrometry (FAB-MS) and liquid secondary ion mass spectrometry (LSIMS).

Oleoyl proline is an N-acyl amine that can be detected in bovine brain extracts and D. melanogaster larvae using mass spectrometry. In a preclinical model of pain, mice lacking fatty acid amide hydrolase (FAAH KO) had decreased N-oleoyl proline levels in

18:0 LYSO-PE is a compound that induces an increase in [Ca2+]i and can be used as a phospholipid (PL) standard for lipid analysis by electrospray mass spectrometry (ESI-MS) MS.

Cholesteryl behenate is a standard in electrospray ionization tandem mass spectrometry for the analysis of cholesteryl esters and cholesterol.

Glutarylcarnitine (O-glutaroyl-L-carnitine) is a diagnostic metabolite for malonic aciduria and glutaric aciduria type I monitored in most tandem mass spectrometry newborn screening programmes.

N,N'-Carbonyldiimidazole is a biological cross-linking agent that has great application in mass spectrometry to detect the purity of compounds.

1-1(Z)-Octadecenyl-2-docosahexaenoyl-sn-glycero-3-PE (18:0p 22:6-PE) is a lipid identified in rat brain tissue using mass spectrometry imaging techniques. It exhibits specific structural and distribution properties, allowing the differentiation of isomers of various fatty acid chains through refined methods.

Cardiolipin (16:0 18:1 16:0 18:1) (16:0-18:1 Cardiolipin) sodium is an anionic phospholipid composed of long-chain fatty acid palmitic acid and monounsaturated fatty acid oleic acid. This compound can be utilized in the synthesis of nanodisk lipid bilayers for in situ mass spectrometry applications.

Lasiocarpine N-oxide, a natural compound, has been identified at higher concentrations in many tea bags, herbal drugs, and honey via mass spectrometry.

Flavone glycoside from Robinia with antibacterial and diuretic properties; derived from kaempferol.The ability of robinin to reverse the multidrug resistance of the human colon cancer cell line Colo 320 expreβing MDR1 LRP was explored by monitoring their uptake of Rhodamine 123, but was shown to have minimal effect. Robinin (NSC-9222) was detected in lysates of the human breast cancer cell line MCF-7 using liquid chromatography-tandem maβ spectrometry.

(±)10-HDHA is an autoxidation product of docosahexaenoic acid (DHA) in vitro.[1][2] It is also produced from incubations of DHA in rat liver, brain, and intestinal microsomes.[3][4][5] (±)10-HDHA is a potential marker of oxidative stress in brain and retina where DHA is an abundant polyunsaturated fatty acid. Reference:[1]. VanRollins, M., and Murphy, R.C. Autooxidation of docosahexaenoic acid: Analysis of ten isomers of hydroxydocosahexaenoate. J. Lipid Res. 25(5), 507-517 (1984).[2]. Reynaud, D., Thickitt, C.P., and Pace-Asciak, C.R. Facile preparation and structural determination of monohydroxy derivatives of docosahexaenoic acid (HDoHE) by α-tocopherol-directed autoxidation. Anal. Biochem. 214(1), 165-170 (1993).[3]. VanRollins, M., Baker, R.C., Sprecher, H., et al. Oxidation of docosahexaenoic acid by rat liver microsomes. J. Biol. Chem. 259(9), 5776-5783 (1984).[4]. Yamane, M., Abe, A., and Yamane, S. High-performance liquid chromatography-thermospray mass spectrometry of epoxy polyunsaturated fatty acids and epoxyhydroxy polyunsaturated fatty acids from an incubation mixture of rat tissue homogenate. J. Chromatogr. 652(2), 123-136 (1994).[5]. Kim, H.Y., Karanian, J.W., Shingu, T., et al. Sterochemical analysis of hydroxylated docosahexaenoates produced by human platelets and rat brain homogenate. Prostaglandins 40(5), 473-490 (1990).

Pregnanetriol is a metabolite of 17α-hydroxyprogesterone .1,2It is formed from 17α-hydroxyprogesterone by reduction of the C-20 ketone.2Urinary levels of pregnanetriol are elevated in patients with 21-hydroxylase deficiency and congenital adrenal hyperplasia.3,4 1.Kamrath, C., Hartmann, M.F., Boettcher, C., et al.Diagnosis of 21-hydroxylase deficiency by urinary metabolite ratios using gas chromatography-mass spectrometry analysis: Reference values for neonates and infantsJ. Steroid Biochem. Mol. Biol.15610-16(2016) 2.Schiffer, L., Barnard, L., Baranowski, E.S., et al.Human steroid biosynthesis, metabolism and excretion are differentially reflected by serum and urine steroid metabolomes: A comprehensive reviewJ. Steroid Biochem. Mol. Biol.194105439(2019) 3.Disorders of steroidogenesis guide to steroid profiling and biochemical diagnosis1(2019) 4.Shackleton, C.H.L.Role of a disordered steroid metabolome in the elucidation of sterol and steroid biosynthesisLipids47(1)1-12(2012)

N-desmethyl Rosuvastatin is an active metabolite of the HMG-CoA reductase inhibitor rosuvastatin .1,2N-desmethyl Rosuvastatin is formed when rosuvastatin undergoes demethylation, primarily by the cytochrome P450 (CYP) isoform CYP2C9 and to a lesser extent by CYP2C19 and CYP3A4.1 1.Macwan, J.S., Ionita, I.A., and Akhlaghi, F.A simple assay for the simultaneous determination of rosuvastatin acid, rosuvastatin-5S-lactone, and N-desmethyl rosuvastatin in human plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS)Anal. Bioanal. Chem.402(3)1217-1227(2012) 2.Bai, X., Wang, X.P., He, G.D., et al.Simultaneous determination of rosuvastatin, rosuvastatin-5 S-lactone, and N-desmethyl rosuvastatin in human plasma by UPLC-MS/MS and its application to clinical studyDrug Res. (Stuttg.)68(6)328-334(2018)

Tolmetin β-D-Glucuronide has reactive properties with human serum albumin, allowing identification of the binding site and reaction mechanism by tandem mass spectrometry.

MitoA is a ratiometric mass spectrometry probe that can be used for assessing changes in H2S within mitochondria in vivo. MitoA contains a triphenylphosphonium cation component that drives its accumulation in mitochondria where its aryl azide moiety selectively reacts with H2S to produce an amine product, MitoN. Quantifying the MitoN/MitoA ratio by LC-MS/MS reflects the mitochondrial matrix H2S concentration. In a mouse model of acute myocardial infarction with MitoA administered prior to ischemia, the MitoN/MitoA ratio is increased only in the region of ischemia.

Cholesteryl heptadecanoate is a cholesterol ester (CE) formed by the condensation of cholesterol with heptadecanoic acid, a C-17 saturated fatty acid that does not occur in any natural animal or vegetable fat at high concentrations. As such, it is commonly used as an internal standard for the quantification of cholesterol esters by GC- or LC-mass spectrometry. CEs are major constituents of lipoprotein particles carried in blood and accumulate in the fatty acid lesions of atherosclerotic plaques. CEs of various fatty acids are major constituents of murine and human adrenal glands.

N-3-hydroxydecanoyl-DL-Homoserine lactone is a bacterial quorum-sensing molecule.1It activates SdiA (EC50= 0.6 μM), a transcription factor that detects N-acyl homoserine lactones (AHLs), in the 14028/pJNS25 strain ofS. enterica.2 1.Fekete, A., Frommberger, M., Rothballer, M., et al.Identification of bacterial N-acylhomoserine lactones (AHLs) with a combination of ultra-performance liquid chromatography (UPLC), ultra-high-resolution mass spectrometry, and in-situ biosensorsAnal. Bioanal. Chem.387455-467(2007) 2.Janssens, J.C.A., Metzger, K., Daniels, R., et al.Synthesis of N-acyl homoserine lactone analogues reveals strong activators of SdiA, the Salmonella enterica serovar Typhimurium LuxR homologueAppl. Environ. Microb.73(2)535-544(2007)

Dichloroiodomethane is a natural compound found in human beings[1].

(±)-11(12)-DiHET is an oxylipin. 11(S),12(S)-DiHET and 11(R),12(R)-DiHET are vicinal diols formedviaenzymatic hydration of 11(12)-EET by cytosolic or soluble epoxide hydrolases in a non-stereoselective manner.1,2,3(±)11(12)-DiHET MaxSpec standard is a quantitative grade standard of (±)11(12)-DiHET that has been prepared specifically for mass spectrometry and related applications where quantitative reproducibility is required. The solution has been prepared gravimetrically and is supplied in a deactivated glass ampule sealed under argon. The concentration was verified by comparison to an independently prepared calibration standard. This (±)11(12)-DiHET MaxSpec standard is guaranteed to meet identity, purity, stability, and concentration specifications and is provided with a batch-specific certificate of analysis. Ongoing stability testing is performed to ensure the concentration remains accurate throughout the shelf life of the product.Note: The amount of solution added to the vial is in excess of the listed amount. Therefore, it is necessary to accurately measure volumes for preparation of calibration standards. Follow recommended storage and handling conditions to maintain product quality.

5,6-dimethyl-2-Thiouracil is a heterocyclic building block that has been used in the synthesis of anti-HIV-1 pyrimidinones.1 It has also been used as an internal standard for the quantification of thyreostats, including 2-thiouracil, in bovine plasma.2 |1. Navrotskii, M.B. Synthesis and anti-HIV-1 activity of new 2-[(2-phthalimidoethyl)thio]-4(3H)-pyrimidinone derivatives. Pharm. Chem. J. 39(9), 466-467 (2005).|2. Schmidt, K.S. In-house validation and factorial effect analysis of a liquid chromatography-tandem mass spectrometry method for the determination of thyreostats in bovine blood plasma. Anal. Bioanal. Chem. 406(3), 735-743 (2014).