1
|
Fu Q, Dong W, Ge D, Ke Y, Jin Y. Supercritical fluid-based method for selective extraction and analysis of indole alkaloids from Uncaria rhynchophylla. J Chromatogr A 2023; 1710:464410. [PMID: 37776825 DOI: 10.1016/j.chroma.2023.464410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 09/02/2023] [Accepted: 09/21/2023] [Indexed: 10/02/2023]
Abstract
The development of an approach based on simultaneous supercritical fluid extraction-sample cleanup, followed by supercritical fluid chromatography/tandem mass spectrometry (SFE-SFC-MS/MS) was as a tool for the extraction, separation and characterization of indole alkaloids of Uncaria rhynchophylla. A two-step SFE method was designed. A mixture of the U. rhynchophylla sample and an adsorbent named C18SCX with the ratio of 1:1 (w/w) was placed into an extraction cell. The extraction temperature was 40 °C and the pressure was 25 Mpa. In the first step, 10 % EtOH as the co-solvent was used to extract for 60 min, which was considered as a cleanup process to remove non-alkaloid components. In the second step, 0.1 % DEA was added to 10 % EtOH and it extracted for 60 min to obtain the desired extract. By introducing an additional adsorbent, the specificity of SFE towards alkaloids was greatly improved. An SFC-MS/MS method was then utilized for analysis of the SFE extract. Using 2-EP as stationary phase with the gradient elution of 0-10 min, 5-25 % EtOH (+0.05 % DEA) in CO2, column temperature 40 °C, and back pressure 13.8 Mpa, 10 peaks were separated within 8 min. Further MS/MS analysis confirmed that nine of the 10 peaks in the SFE extract were indole alkaloids. This study developed a supercritical fluid-based method specifically towards extraction and analysis of alkaloids, which is helpful to the study of alkaline compounds in complex samples.
Collapse
Affiliation(s)
- Qing Fu
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Wenwen Dong
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Dandan Ge
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Yanxiong Ke
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China
| | - Yu Jin
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China.
| |
Collapse
|
2
|
A one-step sample pretreatment and loading method for complex sample separation with supercritical fluid chromatography. J Supercrit Fluids 2022. [DOI: 10.1016/j.supflu.2022.105516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
3
|
On-line supercritical fluid extraction-supercritical fluid chromatography (SFE-SFC) at a glance: A coupling story. Trends Analyt Chem 2021. [DOI: 10.1016/j.trac.2021.116433] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
4
|
A sensitive liquid chromatography-tandem mass spectrometric method for determination of five β-blockers after labeling with either hydrazonoyl chloride or dansyl chloride reagent. J Chromatogr B Analyt Technol Biomed Life Sci 2020; 1160:122383. [DOI: 10.1016/j.jchromb.2020.122383] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 09/01/2020] [Accepted: 09/08/2020] [Indexed: 12/26/2022]
|
5
|
Detection limit enhancement of antiarrhythmic drugs in human plasma using capillary electrophoresis with dispersive liquid–liquid microextraction and field-amplified sample stacking method. Bioanalysis 2015; 7:21-37. [DOI: 10.4155/bio.14.175] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Background: A new capillary zone electrophoresis (CZE) with ultraviolet detection method has been developed and validated for the analysis of four antiarrhythmic drugs in human plasma samples. Methods: In this study, a dispersive liquid–liquid microextraction (DLLME) coupled with field-amplified sample stacking (FASS) was employed for biological samples clean-up and sensitivity enhancement in CZE. Results: Under optimum DLLME-FASS-CZE conditions, enhancement factors were in the range of 157–314. The method was validated over the concentration range of 20–800 ng/ml in human plasma. Inter- and intra-day precision and the accuracy were less than 20%; the detection limits ranged from 2.5 to 4.7 ng/ml. Furthermore, the validated method was successfully applied to the detection of studied drugs in patients’ plasma samples.
Collapse
|
6
|
Salt-assisted LLE combined with field-amplified sample stacking in CE for improved determination of beta blocker drugs in human urine. Bioanalysis 2014; 6:319-34. [DOI: 10.4155/bio.13.303] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Background: A simple and sensitive CE method was developed and validated for the analysis of some beta blockers in human urine. Methods: In this study, salting-out assisted LLE combined with field-amplified sample stacking method was employed for biological sample clean-up and sensitivity enhancement in CE. Results: Under the optimal conditions good linearity (r2 ≥0.998) was obtained, within 0.025–1 µg/ml for propranolol and metoprolol, and within 0.05–1 µg/ml for carvedilol in urine samples. LODs and LLOQs ranged from 0.005 to 0.015 µg/ml, and from 0.025 to 0.05 µg/ml, respectively. The RSDs of intra- and inter-day analysis of examined compounds were less than 4.0%. The recoveries were in the range of 98–119%. Conclusion: The validated method is successfully applied to determine propranolol, metoprolol and carvedilol in human urine samples obtained from the patients who received these drugs.
Collapse
|
7
|
Xu L, Guo Q, Yu H, Huang J, You T. Simultaneous determination of three β-blockers at a carbon nanofiber paste electrode by capillary electrophoresis coupled with amperometric detection. Talanta 2012; 97:462-7. [DOI: 10.1016/j.talanta.2012.04.063] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 04/28/2012] [Accepted: 04/30/2012] [Indexed: 02/09/2023]
|
8
|
Gas chromatography–mass spectrometry determination of pharmacologically active substances in urine and blood samples by use of a continuous solid-phase extraction system and microwave-assisted derivatization. J Chromatogr B Analyt Technol Biomed Life Sci 2012; 891-892:12-9. [DOI: 10.1016/j.jchromb.2012.02.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Revised: 02/03/2012] [Accepted: 02/09/2012] [Indexed: 11/22/2022]
|
9
|
Umezawa H, Lee X, Arima Y, Hasegawa C, Izawa H, Kumazawa T, Sato K. Simultaneous determination ofβ‐blockers in human plasma using liquid chromatography–tandem mass spectrometry. Biomed Chromatogr 2008; 22:702-11. [DOI: 10.1002/bmc.987] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
10
|
Kang X, Pan C, Xu Q, Yao Y, Wang Y, Qi D, Gu Z. The investigation of electrospun polymer nanofibers as a solid-phase extraction sorbent for the determination of trazodone in human plasma. Anal Chim Acta 2007; 587:75-81. [DOI: 10.1016/j.aca.2007.01.021] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2006] [Revised: 01/06/2007] [Accepted: 01/10/2007] [Indexed: 10/23/2022]
|
11
|
Nevado JJB, Flores JR, Peñalvo GC, Bernardo FJG. Development and validation of a capillary zone electrophoresis method for the determination of propranolol and N-desisopropylpropranolol in human urine. Anal Chim Acta 2006. [DOI: 10.1016/j.aca.2005.11.070] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
12
|
Johnson RD, Lewis RJ. Quantitation of atenolol, metoprolol, and propranolol in postmortem human fluid and tissue specimens via LC/APCI-MS. Forensic Sci Int 2006; 156:106-17. [PMID: 16410160 DOI: 10.1016/j.forsciint.2005.01.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2004] [Revised: 01/04/2005] [Accepted: 01/05/2005] [Indexed: 11/20/2022]
Abstract
Hypertension is a growing medical concern in the United States. With the number of Americans suffering from hypertension increasing, the use of antihypertensives such as beta-blockers is increasing as well. In fact, three beta-blockers - atenolol, metoprolol and propranolol - were among the 200 most prescribed medications in the United States in 2003. Pilots that successfully manage their hypertension can remain certified to fly. The Federal Aviation Administration currently designates approximately 8% of active pilots as "hypertensive with medication". The Civil Aerospace Medical Institute (CAMI) performs toxicological evaluation on victims of fatal aviation accidents. At CAMI beta-blockers are analyzed using gas chromatography with mass spectrometric detection. We have, however, recently developed a liquid chromatography with mass spectrometric detection (LC/MS) method for the simultaneous quantitation of three commonly prescribed beta-blockers, atenolol, metoprolol and propranolol. One advantage of our LC/MS method is the specificity provided by an ion trap MS. Utilizing an ion trap MS, we were able to conduct MS/MS and MS/MS/MS on each analyte. This method also eliminates the time-consuming and costly derivitization step necessary during GC/MS analysis. Additionally, by utilizing this novel method, any concerns about beta-blocker metabolite and/or sample matrix interference are eliminated. The limits of detection for this method ranged from 0.39 to 0.78 ng/mL and the linear dynamic range was generally 1.6-3200 ng/mL. The extraction efficiencies for each analyte ranged from 58% to 82%. This method was successfully applied to postmortem fluid and tissue specimens obtained from victims of three separate aviation accidents.
Collapse
Affiliation(s)
- Robert D Johnson
- Civil Aerospace Medical Institute, Federal Aviation Administration, Analytical Toxicology and Accident Research Laboratory, AAM-610, CAMI Building, RM 205, 6500 S. Macarthur Blvd, Oklahoma City, OK 73169-6901, USA.
| | | |
Collapse
|
13
|
Li X, Zeng Z, Hu M, Mao M. High operationally stable sol-gel diglycidyloxycalix[4]arene fiber for solid-phase microextraction of propranolol in human urine. J Sep Sci 2005; 28:2489-500. [PMID: 16405179 DOI: 10.1002/jssc.200500029] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A simple, sensitive, and accurate method for the determination of propranolol in human urine has been developed based on solid-phase microextraction (SPME) followed by GC-flame ionization detection (FID). The sol-gel 5,11,17,23-tetra-tert-butyl-25,27-dihydroxy-26,28-diglycidyloxycalix[4]arene/hydroxy-terminated silicone oil (diglycidyloxy-C[4]/OH-TSO) fiber was prepared to accommodate to the harsh extraction conditions. It possesses excellent alkali-proof ability and retains its extraction characteristics intact even after treatment with highly alkaline (4 mol/L) NaOH solution. Direct chemical bonding of the coating to the fiber surface provides it with excellent solvent resistance and the introduction of calixarene enhances its thermal stability. The newly developed sol-gel calixarene coating was effectively used for the extraction of propranolol in human urine. No interference with the determination of propranolol was observed from the urine components. Standard curves were linear in the range 50-5000 microg/L for headspace-SPME (HS-SPME) and 25-25000 microg/L for direct-SPME (Dir-SPME) with correlation coefficients better than 0.9999. The detection limit was 0.275 microg/L for HS-SPME and 0.193 microg/L for Dir-SPME. The method was validated using standard addition methodology and recovery values were between 91.4 and 117% for both the sampling modes with the RSDs less than 6% at different concentration levels in the linear ranges. The results obtained by both the sampling modes were feasible, and no significant differences between them regarding accuracy, precision, and detection limits were seen.
Collapse
Affiliation(s)
- Xiujuan Li
- Department of Chemistry, Wuhan University, Wuhan, China
| | | | | | | |
Collapse
|
14
|
Bauza R, Ríos A, Valcárcel M. Enantioselective Supercritical Fluid Extraction from Racemic Mixtures by Use of Chiral Selectors. SEP SCI TECHNOL 2005. [DOI: 10.1081/ss-120027569] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
15
|
|
16
|
Murillo Pulgarín JA, Alañón Molina A, Fernández López P, Alañón Pardo MT. Fast determination of propranolol in urine and pharmaceutical preparations by stopped-flow and micellar-stabilized room-temperature phosphorescence: validation of the method. Anal Biochem 2003; 312:167-74. [PMID: 12531202 DOI: 10.1016/s0003-2697(02)00438-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The stopped-flow mixing technique has been used to study the kinetic determination of propranolol by means of micellar-stabilized room-temperature phosphorescence. This mixing system diminishes the time required for the deoxygenation of micellar medium by sodium sulfite, allowing a kinetic curve that levels off within only 7s to be obtained. The phosphorescence enhancers thallium (I) nitrate, sodium dodecyl sulfate, and sodium sulfite were optimized to obtain maximum sensitivity and selectivity. A pH value of 6.54 was selected as adequate for phosphorescence development. The kinetic curves of propranolol phosphorescence were scanned at lambda(ex)=290 nm and lambda(em)=524 nm. The calibration graphs were linear for the concentration range from 25 to 400 ng mL(-1). The phosphorescence lifetime of propranolol is approximately 1210 micros. The detection limit calculated as proposed clayton was 13.53 ng mL(-1) and by applying the error propagation theory, the detection limit was 8.37 ng mL(-1). The repeatability was studied using 10 solutions of 200 ng mL(-1) of propranolol; if error propagation theory is assumed, the relative error is 1.94%. The standard deviation for a replicate sample was 4.0 ng mL(-1). This method was successfully applied to the determination of propranolol in commercial formulations and in urine. Suitable recovery values were obtained.
Collapse
Affiliation(s)
- J A Murillo Pulgarín
- Department of Analytical Chemistry and Foods Technology, University of Castilla-La Mancha, Campus Universitario Avda Camilo Jose Cela, 10, Ciudad Real 13071, Spain.
| | | | | | | |
Collapse
|
17
|
Ruiz-Angel MJ, Fernández-López P, Murillo-Pulgarín JA, García-Alvarez-Coque MC. Control of propranolol intake by direct chromatographic detection of alpha-naphthoxylactic acid in urine. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 767:277-83. [PMID: 11885857 DOI: 10.1016/s1570-0232(01)00571-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A rapid chromatographic procedure with a C18 column, a mobile phase of 0.15 M sodium dodecyl sulfate (SDS)-10% (v/v) 1-propanol at pH 3 (0.01 M phosphate buffer), and fluorimetric detection, is reported for the control of propranolol (PPL) intake in urine samples, which are injected directly without any other treatment than filtration. The peak of PPL was only observed in samples taken a few hours after ingestion of the drug due to its extensive conjugation and metabolisation. The detection of several unconjugated PPL metabolites was therefore considered: desisopropylpropranolol (DIP), propranolol glycol (PPG), alpha-naphthoxylactic acid (NLT) and alpha-naphthoxyacetic acid (NAC). NLT showed the best characteristics: it eluted at a much shorter retention time than PPL, its concentration in urine samples was greater and it did not present any interference from endogeneous compounds in urine, common drugs or drugs administered in combination with PPL. The limit of quantification, measured as the concentration of analyte providing a relative standard deviation of 20%, was 24 ng/ml, and the day-to-day imprecision was below 4% for concentrations above 200 ng/ml. The procedure allows the routine control of PPL at therapeutic urine levels. Urinary excretion studies showed that the detection of NLT is possible at least up to 20-30 h after oral administration.
Collapse
Affiliation(s)
- M J Ruiz-Angel
- Departamento de Química Analítica, Facultad de Química, Universidad de Valencia, Burjasot, Spain
| | | | | | | |
Collapse
|
18
|
Klime J, Sochor J, Kríz J. A study of the conditions of the supercritical fluid extraction in the analysis of selected anti-inflammatory drugs in plasma. FARMACO (SOCIETA CHIMICA ITALIANA : 1989) 2002; 57:117-22. [PMID: 11902653 DOI: 10.1016/s0014-827x(01)01182-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Supercritical fluid extraction (SFE) was employed to analyze selected anti-inflammatory drugs in plasma. Evaluation of selected drugs (ibuprofen, indomethacin, and flufenamic acid) was performed using the HPLC method on columns with the reverse phase C-18 and detection in the UV region of the spectrum. A study of the conditions of SFE carried out for 30 min at 50 degrees C investigated the magnitude of the pressure of carbon dioxide suitable for drug extraction, the selection of the collecting solvent, and the modification of CO2 with an organic solvent. The results of the study made it possible to determine the optimal procedure for SFE of ibuprofen, indomethacin, and flufenamic acid from plasma, which renders their HPLC quantification possible.
Collapse
Affiliation(s)
- Jiri Klime
- Department of Pharmaceutical Chemistry and Drug Control, Faculty of Pharmacy, Charles University, Hradec Králové, Czech Republic.
| | | | | |
Collapse
|
19
|
van Hout MWJ, van Egmond WMA, Franke JP, de Zeeuw RA, de Jong GJ. Feasibility of the direct coupling of solid-phase extraction-pipette tips with a programmed-temperature vaporiser for gas chromatographic analysis of drugs in plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 766:37-45. [PMID: 11824396 DOI: 10.1016/s0378-4347(01)00431-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Solid-phase extraction-pipette tips (SPE-PTs) were used for micro solid-phase extraction of lidocaine and diazepam from plasma. Off-line extraction was followed by on-line desorption. On-line desorption was carried out by direct coupling of the SPE-PTs with the liner of the programmed-temperature vaporiser. This coupling only required shortening of the liner by maximally 16 mm, cutting the SPE-PT, and equipping the remaining part with two O-rings. Due to the heating of the injector the SPE-PTs were heated as well, which resulted in a significant amount of impurities. Pre-heating and pre-washing was performed prior to the extraction to reduce the impurity level. The internal coupling device was applied successfully for the analysis of plasma samples with gas chromatography (GC) and mass-selective detection. Detection limits of 0.75 ng/ml and 2.5 ng/ml were obtained for lidocaine and diazepam, respectively, using 200 microl plasma. Recoveries for both compounds were about 80%. Although it is possible, the internal coupling device was not developed to be used as such. The main goal of this coupling was to show the feasibility of the integration of SPE-PTs with GC and to realize an important step to new automated SPE-GC systems.
Collapse
Affiliation(s)
- M W J van Hout
- Department of Analytical Chemistry and Toxicology, University Centre for Pharmacy, Groningen, The Netherlands.
| | | | | | | | | |
Collapse
|
20
|
Bauza R, Rı́os A, Valcárcel M. Supercritical fluid extraction with in situ chiral derivatization for the enantiospecific determination of ibuprofen in urine samples. Anal Chim Acta 2001. [DOI: 10.1016/s0003-2670(01)01383-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
21
|
Shimmo M, Hyötyläinen T, Hartonen K, Riekkola ML. On-line coupled supercritical fluid extraction-liquid chromatography-gas chromatography-mass spectrometry for the analysis of organic acids. ACTA ACUST UNITED AC 2001. [DOI: 10.1002/mcs.1043] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
22
|
Wang SM, Giang YS, Ling YC. Simultaneous supercritical fluid extraction and chemical derivatization for the gas chromatographic-isotope dilution mass spectrometric determination of amphetamine and methamphetamine in urine. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 759:17-26. [PMID: 11499622 DOI: 10.1016/s0378-4347(01)00195-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
An in-situ supercritical fluid extraction (SFE) and chemical derivatization (ChD) procedure followed by gas chromatography-isotope dilution mass spectrometry (GC-MS) for the determination of amphetamines in urine is described and evaluated. While using celite as the SFE wet-support, the one-pot sample pretreatment procedure also employs ammonium water to alkalize the urine matrix that contains protonated amphetamine (AP) and methamphetamine (MA). The mean recoveries achieved by simultaneous SFE-ChD, i.e., 95% (RSD=3.8%) for AP and 89% (RSD=4.0%) for MA, are significantly better than the corresponding overall recoveries obtained upon stepwise SFE-ChD, suggesting the unreacted trifluoroacetic anhydride (TFA) in the former procedure has strengthened the extracting power of CO, fluid as has been evidenced by a control test. As to GC-MS analysis, the optimal qualitative ions and quantitative ions of the respective analytes were determined via a rigorous evaluation process. Thus, the regression calibration curves for AP and MA in urine are linear within 100 approximately 50,000 ng/ml, with correlation coefficients typically exceeding 0.999. The limits of detection determined by two methods for AP and MA vary from 19 to 50 ng/ml, and limits of quantitation from 21 to 100 ng/ml. Precisions calculated for the triplicate analyses of AP and MA in a 500-ng/ml spiked control, two real-case samples and two quasi real-case samples, respectively, using regression calibration are typically below 10%. The method is simple and reliable. It may serve as an alternative to the existing confirmatory protocol for forensic urine drug testing.
Collapse
Affiliation(s)
- S M Wang
- Department of Forensic Science, Central Police University, Kueishan, Taoyuan, Taiwan
| | | | | |
Collapse
|
23
|
Ohashi N, Yoshikawa M. Rapid and sensitive quantification of 8-isoprostaglandin F2alpha in human plasma and urine by liquid chromatography-electrospray ionization mass spectrometry. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 746:17-24. [PMID: 11048736 DOI: 10.1016/s0378-4347(00)00201-2] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The isoprostane, 8-isoprostaglandin F2alpha (8-iso-PGF2alpha), is produced non-enzymatically by direct oxidation of arachidonic acid on the cell surface by oxygen radicals. We developed a new assay method for 8-iso-PGF2alpha using 2H4-8-iso-PGF2alpha as the internal standard (I.S.) by high-performance liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS). For this assay, we established a very simple and rapid pretreatment method using a membrane filter-type solid-phase extraction column (Empore disk cartridge) for human urine extracts or intact plasma. LC-ESI-MS was performed in the selected ion monitoring (SIM) mode using target ions at m/z 353.24 (8-iso-PGF2alpha) and m/z 357.26 (I.S.) with a resolution of 1,500. The imprecision for this method was below 13.7%. Mean inaccuracy was 8.7% for added levels of 8-iso-PGF2alpha up to 5,000 pg/ml of urine and 500 pg/ml of plasma. Determination of plasma and urinary 8-iso-PGF2alpha concentrations in healthy subjects by the present method revealed that its urinary concentration in smokers tends to be higher than that in nonsmokers.
Collapse
Affiliation(s)
- N Ohashi
- Discovery Research Laboratory, Tanabe Seiyaku Company Limited, Toda-shi, Saitama, Japan.
| | | |
Collapse
|
24
|
van Hout MW, de Zeeuw RA, de Jong GJ. Coupling device for desorption of drugs from solid-phase extraction-pipette tips and on-line gas chromatographic analysis. J Chromatogr A 1999; 858:117-22. [PMID: 10544897 DOI: 10.1016/s0021-9673(99)00806-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Solid-phase extraction-pipette tips were used for micro solid-phase extraction of lidocaine and diazepam. Off-line desorption was done after in-vial collection for reference purposes, whereas with on-line desorption the eluate was directly introduced in the gas chromatograph. With both methods the total eluate (100 microl) was introduced into the GC system, which was equipped with a programmed-temperature vaporiser (PTV) for large volume injection. For on-line desorption a laboratory-made coupling device was developed to connect the pipette tips with the injector of the PTV. The coupling device was applied successfully since no leakage occurred at the connection of the coupling device and the pipette tip. No significant differences in recovery of lidocaine and diazepam and in presence of impurities were observed between chromatograms obtained with either off-line or on-line desorption. Preliminary experiments with standard solutions showed recoveries of about 75% for a concentration level of 1 microg/ml. The system seems particularly suitable for high-throughput analysis.
Collapse
Affiliation(s)
- M W van Hout
- Department of Analytical Chemistry and Toxicology, University Centre for pharmacy, Groningen, The Netherlands.
| | | | | |
Collapse
|
25
|
Segura J, Ventura R, Jurado C. Derivatization procedures for gas chromatographic-mass spectrometric determination of xenobiotics in biological samples, with special attention to drugs of abuse and doping agents. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 713:61-90. [PMID: 9700553 DOI: 10.1016/s0378-4347(98)00089-9] [Citation(s) in RCA: 162] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The development of low cost MS detectors in recent years has promoted an important increase in the applicability of GC-MS system to analyze for the presence of foreign substances in the human body. Drugs and toxic agents are in vivo metabolized in such a way that more polar compounds are usually formed. Derivatization of these metabolites is often an unavoidable requirement for gas chromatographic analysis. Application of derivatization methods in recent years has been relevant, especially for silylation, acylation, alkylation and the formation of cyclic or diastereomeric derivatives. Given the relevance of drug of abuse testing in modern toxicology, main derivatization procedures for opiates, cocaine, cannabis, amphetamines, benzodiazepines and LSD have been reviewed. Papers describing the analyses of drugs of abuse in matrixes other than blood, such as hair or sweat, have received special attention. Advances in derivatization for sports drug testing have been particularly relevant for anabolic steroids, diuretics and corticosteroids. Among the several methodologies applied, the formation of trimethylsilyl, perfluoroacyl or methylated derivatives have proved to be both versatile and extensively used. Further advances in derivatization for GC-MS applications in clinical and forensic toxicology will depend on the one hand on the degree of further use of GC-MS for routine applications and, on the other hand, on the alternative progress made for developments in LC-MS or CE-MS. Last but not least, the appearance of comprehensive libraries in which reference spectra for different derivatives of many drugs and their metabolites are collected will have an important impact on the expansion of derivatization in GC-MS for toxicological applications.
Collapse
Affiliation(s)
- J Segura
- Institut Municipal d'Investigació Mèdica IMIM, Drug Research Unit, Barcelona, Spain
| | | | | |
Collapse
|
26
|
Affiliation(s)
- T. L. Chester
- Miami Valley Laboratories, The Procter & Gamble Company, P.O. Box 538707, Cincinnati, Ohio 45253-8707
| | - J. D. Pinkston
- Miami Valley Laboratories, The Procter & Gamble Company, P.O. Box 538707, Cincinnati, Ohio 45253-8707
| | - D. E. Raynie
- Miami Valley Laboratories, The Procter & Gamble Company, P.O. Box 538707, Cincinnati, Ohio 45253-8707
| |
Collapse
|
27
|
Abstract
Coupling chemical derivatization reactions with supercritical fluid extraction for the determination of trace levels of organic and organometallic compounds in liquid and solid matrices is reviewed. Derivatization is used to increase the solubility of analytes in supercritical carbon dioxide, to increase analyte volatility for gas chromatographic analysis and to integrate sample preparation steps in order to reduce analysis time and costs. Reactions that are covered in this review derivatize analytes possessing carboxyl, hydroxyl, sulfonic and amino groups to their alkyl, acyl and silyl derivatives. Derivatization is also used to derivatize active matrix sites to facilitate the release of analytes. Approaches used to couple derivatization with supercritical fluid extraction include reactions conducted prior to extraction, under in-site supercritical fluid conditions, or off-line under injection port conditions. Examples of applications are given for organic and organometallic compounds in environmental, pharmaceutical and agricultural product samples.
Collapse
Affiliation(s)
- J A Field
- Department of Agricultural Chemistry, Oregon State University, Corvallis 97331, USA
| |
Collapse
|
28
|
|