Mass spectrometry samples solid-phase extraction

A. Kloepfer, M. Jekel, and T. Reemtsma. Determination of benzothiazoles from complex aqueous samples by liquid chromatography-mass spectrometry following solid-phase extraction. /. Chromatogr. A, 1058, 81-88, 2004. 

The liquid chromatography - tandem mass spectrometry (LC/MS/MS) technique was proposed for the determination of corticosteroids in plasma and cerebrospinal fluid (CSF, liquor) of children with leucosis. Preliminai y sample prepai ation included the sedimentation of proteins, spinning and solid-phase extraction. MS detection was performed by scanning selected ions, with three chai acteristic ions for every corticosteroids. The limit of detection was found 80 pg/ml of plasma. 

C. Aguilar, I. Feirer, R Bonnll, R. M. Marce and D. Barcelo, Monitoring of pesticides in river water based on samples previously stored in polymeric cartridges followed by on-line solid-phase extraction-liquid cliromatography-diode array detection and confirmation by atmospheric pressure chemical ionization mass spectrometry . Anal. Chim. Acta 386 237-248 (1999). 

A new technique has been developed to analyze a- and (3-endosulfan concentrations in human urine (Vidal et al. 1998). Samples are mixed with a buffer solution and then passed through solid phase extraction cartridges for analysis using gas chromatography-tandem mass spectrometry (GC-MS-MS). 

Analytical methods for parent chloroacetanilide herbicides in soil typically involve extraction of the soil with solvent, followed by solid-phase extraction (SPE), and analysis by gas chromatography/electron capture detection (GC/ECD) or gas chromatog-raphy/mass spectrometry (GC/MS). Analytical methods for parent chloroacetanilides in water are similarly based on extraction followed by GC with various detection techniques. Many of the water methods, such as the Environmental Protection Agency (EPA) official methods, are multi-residue methods that include other compound classes in addition to chloroacetanilides. While liquid-liquid partitioning was used initially to extract acetanilides from water samples, SPE using... 

The need to understand the fate of pesticides in the environment has necessitated the development of analytical methods for the determination of residues in environmental media. Adoption of methods utilizing instrumentation such as gas chro-matography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), liquid chromatography/tandem mass spectrometry (LC/MS/MS), or enzyme-linked immunosorbent assay (ELISA) has allowed the detection of minute amounts of pesticides and their degradation products in environmental samples. Sample preparation techniques such as solid-phase extraction (SPE), accelerated solvent extraction (ASE), or solid-phase microextraction (SPME) have also been important in the development of more reliable and sensitive analytical methods. 

Crop material is homogenized with acetonitrile-water (9 1, v/v). The crop extract is centrifuged and an aliquot is rotary evaporated to a small volume. The sample is subjected to a Cig solid-phase extraction (SPE) cleanup procedure. The concentrated eluate is subjected to liquid chromatography/tandem mass spectrometry (LC/MS/MS) analysis. 

Combalbert S, Pype ML, Bemet N, Hemandez-Raquet G (2010) Enhanced methods for conditioning, storage, and extraction of liquid and solid samples of manure for determination of steroid hormones by solid-phase extraction and gas chromatography-mass spectrometry. Anal Bioanal Chem 398 973-984... 

Ferrer and Barcelo [131] used online solid-phase-liquid chromatography mass spectrometry for the simultanous determination of organotin antifouling herbicides in marine water. The solid-phase extraction was carried out on polymeric cartridges after percolation of 100 ml of the seawater sample, and... 

The analyses of illicit drugs and metabolites in the sampled waters were performed following a previously described and validated fully automated method based on on-line solid phase extraction-liquid chromatography-tandem mass spectrometry (on-line SPE-LC-MS/MS) [19]. 

This chapter will review recent advances in mass spectrometry, liquid chromatography, and sample preparation techniques that aim at achieving high throughput. In particular, online solid phase extraction and multiplexed HPLC front ends for quantitative bioanalysis will be discussed in detail. 

Ding J. and Neue U.D., 1999. A new approach to the effective preparation of plasma samples for rapid drug quantitation using online solid phase extraction mass spectrometry. Rapid Commun Mass Spectrom 13 2151. 

Ferrer I. and Barcelo, D., 1999. Simultaneous determination of antifouling herbicides in marina water samples by online solid-phase extraction followed by liquid chromatography-mass spectrometry. J Chromatogr A 854 197. 

Hernandez F. et al., 2001. Rapid direct determination of pesticides and metabolites in environmental water samples at sub-/tg/L level by online solid-phase extraction-liquid chromatography-electrospray tandem mass spectrometry. J Chromatogr A 939 1. 

Zimmer D. et al., 1999. Comparison of turbulent-flow chromatography with automated solid-phase extraction in 96-well plates and liquid-liquid extraction used as plasma sample preparation techniques for liquid chromatography-tandem mass spectrometry. J Chromatogr A 854 1999. 

MOR were comparable (10 ng mL4), whereas those for DHC and EMOR were about fourfold lower. Furthermore, glucuronides were shown to react like the corresponding free opioids. Validation with real urine samples was performed with identification of the peaks by capillary electrophoresis-ion-trap mass spectrometry (CE-MS) after solid-phase extraction. 

Recent studies, including the use of Microtox and ToxAlert test kits [55,56], were carried out for the determination of the toxicity of some non-ionic surfactants and other compounds (aromatic hydrocarbons, endocrine disruptors) before implementation on raw and treated wastewater, followed by the identification and quantification of polar organic cytotoxic substances for samples with more than 20% inhibition. Furthermore, the study of their contribution to the total toxicity was obtained using sequential solid-phase extraction (SSPE) before liquid chromatography-mass spectrometry (LC-MS) detection. This combined procedure allows one to focus only on samples containing toxic substances. 

Tabor and Barber examined the 2800 km reach of the Mississippi river for the occurrence and fate of LAS in waters and bottom sediments [3], Dissolved LAS was concentrated on reversed-phase (RP)-Cis solid-phase extraction (SPE) cartridges, while sediment-bound LAS was extracted with methanol in three 24-h cycles on a rotating mixer. After derivatisation of the extracts to yield the trifluoroethyl esters, analyses were performed by gas chromatography mass spectrometry (GC-MS). Upon enrichment of 900 mL samples, detection limits of 0.1p.gL 1 were achieved. LAS was identified in 21% of the water samples at concentrations ranging from 0.1 to 28 p,g L-1 and was detected at all of the Mississippi river sediment samples at concentrations ranging from 0.01 to 20 mg kg-1 with a mean value of 0.83 mg kg-1. The concentrations of LAS sorbed onto sediment particles generally did not correlate with... 

Rule G, Henion J. 1999. High-throughput sample preparation and analysis using 96-weU membrane solid-phase extraction and liquid chromatography—tandem mass spectrometry for the determination of steroids in human urine. J Am... 

When using PFT with a neutral selector, it is quite difficult to avoid any entrance of the chiral selector into the ionization source, particularly at a high pH, where EOF is important. The use of BGE at low pH and/or coated capillary to minimize EOF is therefore mandatory. However, the coaxial sheath gas, which generally assists the ionization process, leads to an aspirating phenomenon of the chiral selector in the MS direction. Javerfalk et al. were the first to apply PFT with a neutral methyl-/i-CD for the separation of racemic bupivacaine and ropivacaine with a polyacrylamide-coated capillary and an acidic pH buffer (pH 3). Cherkaoui et al. employed another neutral CD (HP-/1-CD) with a PVA-coated capillary for the analysis of amphetamines and their derivatives. To prevent a detrimental aspiration effect, analyses were carried out without nebulization pressure. Numerous other studies presented excellent results such as the enantioselective separation of adrenoreceptor antagonist drugs using tandem mass spectrometry (MS/MS) the separation of clenbuterol enantiomers after solid-phase extraction (SPE) of plasma samples or the use of CD dual system for the simultaneous chiral determination of amphetamine, methamphetamine, dimethamphetamine, and p-hydroxymethamphetamine in urine. 

Conventional radiochemical methods for the determination of long-lived radionuclides at low concentration levels require a careful chemical separation of the analyte, e.g., by liquid-liquid, solid phase extraction or ion chromatography. The chemical separation of the interferents from the long-lived radionuclide at the ultratrace level and its enrichment in order to achieve low detection limits is often very time consuming. Inorganic mass spectrometry is especially advantageous in comparison to radioanalytical techniques for the characterization of radionuclides with long half-lives (> 104 a) at the ultratrace level and very low radioactive environmental or waste samples. 

Truscott, J. B., Jones, P., Fairman, B. E., and Evans, E. H., Determination of actinide elements at femtogram per gram levels in environmental samples by on-line solid phase extraction and sector-field-inductively coupled plasma-mass spectrometry, Anal. Chim. Acta, 433, 245-253, 2001. 

D. Jahr, Determination of alkyl, chloro and mononitrophenols in water by sample-acetylation and automatic on-line solid phase extraction-gas chromatography-mass spectrometry , Chromatographia47 49-56 (1998). 

---