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Colmsjö, Anders
Publications (10 of 22) Show all publications
Elmongy, H., Ahmed, H., Wahbi, A.-A., Amini, A., Colmsjö, A. & Abdel-Rehim, M. (2016). Determination of metoprolol enantiomers in human plasma and saliva samples utilizing microextraction by packed sorbent and liquid chromatography-tandem mass spectrometry. BMC Biomedical chromotography, 30(8), 1309-1317
Open this publication in new window or tab >>Determination of metoprolol enantiomers in human plasma and saliva samples utilizing microextraction by packed sorbent and liquid chromatography-tandem mass spectrometry
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2016 (English)In: BMC Biomedical chromotography, ISSN 0269-3879, E-ISSN 1099-0801, Vol. 30, no 8, p. 1309-1317Article in journal (Refereed) Published
Abstract [en]

A sensitive, accurate and reliable bioanalytical method for the enantioselective determination of metoprolol in plasma and saliva samples utilizing liquid chromatography-electrospray ionization tandem mass spectrometry was developed and validated. Human plasma and saliva samples were pretreated by microextraction by packed sorbent (MEPS) prior to analysis. A new MEPS syringe form with two inputs was used. Metoprolol enantiomers and internal standard pentycaine (IS) were eluted from MEPS sorbent using isopropanol after removal of matrix interferences using aliquots of 5% methanol in water. Complete separation of metoprolol enantiomers was achieved on a Cellulose-SB column (150x4.6mm, 5m) using isocratic elution with mobile phase 0.1% ammonium hydroxide in hexane-isopropanol (80:20, v/v) with a flow rate of 0.8mL/min. A post-column solvent-assisted ionization was applied to enhance metoprolol ionization signal in positive mode monitoring (+ES) using 0.5% formic acid in isopropanol at a flow rate of 0.2mL/min. The total chromatographic run time was 10min for each injection. The detection of metoprolol in plasma and saliva samples was performed using triple quadrupole tandem mass spectrometer in +ES under the following mass transitions: m/z 268.0872.09 for metoprolol and m/z 303.3154.3 for IS. The linearity range was 2.5-500ng/mL for both R- and S-metoprolol in plasma and saliva. The limits of detection and quantitation for both enantiomers were 0.5 and 2.5ng/mL respectively, in both matrices (plasma and saliva). The intra- and inter-day precisions were presented in terms of RSD values for replicate analysis of quality control samples and were <5%; the accuracy of determinations varied from 96 to 99%. The method was able to determine the therapeutic levels of metoprolol enantiomers in both human plasma and saliva samples successfully, which can aid in therapeutic drug monitoring in clinical laboratories.

Keywords
metoprolol enantiomers, chiral chromatography, tandem mass spectrometry, therapeutic drug monitoring, plasma, saliva
National Category
Chemical Sciences
Research subject
Analytical Chemistry
Identifiers
urn:nbn:se:su:diva-133381 (URN)10.1002/bmc.3685 (DOI)000379971200020 ()26766521 (PubMedID)
Available from: 2016-09-09 Created: 2016-09-06 Last updated: 2023-12-05Bibliographically approved
Iadaresta, F., Crescenzi, C., Amini, A., Colmsjö, A., Koyi, H. & Abdel-Rehim, M. (2015). Application of graphitic sorbent for online microextraction of drugs in human plasma samples. Journal of Chromatography A, 1422, 34-42
Open this publication in new window or tab >>Application of graphitic sorbent for online microextraction of drugs in human plasma samples
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2015 (English)In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1422, p. 34-42Article in journal (Refereed) Published
Abstract [en]

In the present work a new sorbent based on graphitized carbon (CarbonX (R) COA) was evaluated in microextraction by packed sorbent (MEPS) for extraction of lidocaine and ropivacaine from human plasma samples. The new graphitic sorbent showed high recoveries of lidocaine and ropivacaine compared to C18 sorbent In the present study the G-MEPS (syringe packed with graphitic sorbent) was connect online with liquid chromatography tandem mass spectrometry (LC-MS/MS). In order to obtain a fast and reliable method different factors affecting MEPS performance were investigated. The extraction efficiency of the graphitic sorbent was compared with silica-based sorbents used in MEPS. The G-MEPS was also evaluated for reuse (50-100 times). The recoveries of lidocaine and ropivacaine from plasma samples were 79% and 82%; respectively. The method was validated according to FDA (Food and Drug Administration) guideline for bioanalytical method validation. Linearity was assessed in the range 5-2000 nmol/L, with coefficient of determination r(2) > 0,995 (n=3) for lidocaine and r(2) > 0.997 (n=3) for ropivacaine. The lower limit of quantification (LLOQ) was 5 nmol/L and the limit of detection (LOD) was 1 nmol/L for studied analytes in plasma samples. For both analytes considered in this study the accuracy values in plasma samples were ranged from 86% to 113%. The Inter-day precisions, expressed as relative standard deviation (%RSD), at three different concentrations (QC-samples) ranged from 8% to 9% for lidocaine, and from 4% to 11% for ropivacaine.

Keywords
Graphitic sorbent, Microextraction by packed sorbent, Lidocaine, Ropivacaine, Carbon X COA, Plasma samples
National Category
Biological Sciences Chemical Sciences
Identifiers
urn:nbn:se:su:diva-124733 (URN)10.1016/j.chroma.2015.10.025 (DOI)000365368300005 ()26499973 (PubMedID)
Available from: 2016-01-12 Created: 2016-01-04 Last updated: 2023-12-05Bibliographically approved
Moein, M. M., Jabbar, D., Colmsjö, A. & Abdel-Rehim, M. (2014). A needle extraction utilizing a molecularly imprinted-sol-gel xerogel for on-line microextraction of the lung cancer biomarker bilirubin from plasma and urine samples. Journal of Chromatography A, 1366, 15-23
Open this publication in new window or tab >>A needle extraction utilizing a molecularly imprinted-sol-gel xerogel for on-line microextraction of the lung cancer biomarker bilirubin from plasma and urine samples
2014 (English)In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1366, p. 15-23Article in journal (Refereed) Published
Abstract [en]

In the present work, a needle trap utilizing a molecularly imprinted sal-gel xerogel was prepared for the on-line microextraction of bilirubin from plasma and urine samples. Each prepared needle could be used for approximately one hundred extractions before it was discarded. Imprinted and non-imprinted sol-gel xerogel were applied for the extraction of bilirubin from plasma and urine samples. The produced molecularly imprinted sol-gel xerogel polymer showed high binding capacity and fast adsorption/desorption kinetics for bilirubin in plasma and urine samples. The adsorption capacity of molecularly imprinted sal-gel xerogel polymer was approximately 60% higher than that of non-imprinted polymer. The effect of the conditioning, washing and elution solvents, pH, extraction time, adsorption capacity and imprinting factor were investigated. The limit of detection and the lower limit of quantification were set to 1.6 and 5 nmol L-1, respectively using plasma or urine samples. The standard calibration curves were obtained within the concentration range of 5-1000 nmol L-1 in both plasma and urine samples. The coefficients of determination values (R-2) were >= 0.998 for all runs. The extraction recovery was approximately 80% for BR in the human plasma and urine samples.

Keywords
Molecularly imprinted polymer, Sol-gel, Microextraction by packed sorbent, Bilirubin, Plasma, Urine
National Category
Chemical Sciences Biochemistry and Molecular Biology
Identifiers
urn:nbn:se:su:diva-109808 (URN)10.1016/j.chroma.2014.09.012 (DOI)000343630500002 ()
Note

AuthorCount:4;

Available from: 2015-01-27 Created: 2014-12-01 Last updated: 2023-12-05Bibliographically approved
Pereira, J., Camara, J. S., Colmsjö, A. & Abdel-Rehim, M. (2014). Microextraction by packed sorbent: an emerging, selective and high-throughput extraction technique in bioanalysis. BMC Biomedical chromotography, 28(6), 839-847
Open this publication in new window or tab >>Microextraction by packed sorbent: an emerging, selective and high-throughput extraction technique in bioanalysis
2014 (English)In: BMC Biomedical chromotography, ISSN 0269-3879, E-ISSN 1099-0801, Vol. 28, no 6, p. 839-847Article in journal (Refereed) Published
Abstract [en]

Sample preparation is an important analytical step regarding the isolation and concentration of desired components from complex matrices and greatly influences their reliable and accurate analysis and data quality. It is the most labor-intensive and error-prone process in analytical methodology and, therefore, may influence the analytical performance of the target analytes quantification. Many conventional sample preparation methods are relatively complicated, involving time-consuming procedures and requiring large volumes of organic solvents. Recent trends in sample preparation include miniaturization, automation, high-throughput performance, on-line coupling with analytical instruments and low-cost operation through extremely low volume or no solvent consumption. Micro-extraction techniques, such as micro-extraction by packed sorbent (MEPS), have these advantages over the traditional techniques. This paper gives an overview of MEPS technique, including the role of sample preparation in bioanalysis, the MEPS description namely MEPS formats (on- and off-line), sorbents, experimental and protocols, factors that affect the MEPS performance, and the major advantages and limitations of MEPS compared with other sample preparation techniques. We also summarize MEPS recent applications in bioanalysis.

Keywords
micro-extraction techniques (ET), micro-extraction by packed sorbent (MEPS), sorbents, applications, future trends
National Category
Analytical Chemistry
Identifiers
urn:nbn:se:su:diva-106077 (URN)10.1002/bmc.3156 (DOI)000337531900018 ()
Note

AuthorCount:4;

Available from: 2014-07-29 Created: 2014-07-21 Last updated: 2023-12-05Bibliographically approved
Daryanavard, S., Jeppsson-Dadoun, A., Andersson, L. I., Hashemi, M., Colmsjö, A. & Abdel-Rehim, M. (2013). Molecularly imprinted polymer in microextraction by packed sorbent for the simultaneous determination of local anesthetics: lidocaine, ropivacaine, mepivacaine and bupivacaine in plasma and urine samples. BMC Biomedical chromotography, 27(11), 1418-1488
Open this publication in new window or tab >>Molecularly imprinted polymer in microextraction by packed sorbent for the simultaneous determination of local anesthetics: lidocaine, ropivacaine, mepivacaine and bupivacaine in plasma and urine samples
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2013 (English)In: BMC Biomedical chromotography, ISSN 0269-3879, E-ISSN 1099-0801, Vol. 27, no 11, p. 1418-1488Article in journal (Refereed) Published
Abstract [en]

This study presents the use of molecularly imprinted polymer (MIP) as packing material for microextraction by packed syringe (MEPS) to achieve higher extraction selectivity. Pentycaine was used as template for MIP. Development and validation of the determination of lidocaine, ropivacaine, mepivacaine and bupivacaine in human plasma and urine samples utilizing MIP-MEPS and liquid chromatography–tandem mass spectrometry (LC-MS/MS) were carried out. The MEPS MIP-cartridge could be used for 100 extractions before it was discarded. The extraction recovery ranged from 60 to 80%. The correlation coefficients values were >0.999 for all assays using lidocaine, ropivacaine, mepivacaine and bupivacaine in the calibration range 5–2000 nmol/L. The accuracy of the studied compounds, given as a percentage variation from the nominal concentration values, ranged from -4.9 to 8.4% using plasma and urine samples. The between-batch precision, given as the relative standard deviation, at three different concentrations (quality control samples) was ranged from −4.7 to 14.0% and from 1.8 to 12.7% in plasma and urine, respectively. The lower limit of quantification and limit of detection of the studied substances were 5.0 and 1.0 nm, respectively

Place, publisher, year, edition, pages
Wiley-Blackwell, 2013
Keywords
MIP, MEPS, plasma and urine samples, local anesthetic drugs, LC-MS/MS
National Category
Analytical Chemistry Biochemistry and Molecular Biology Pharmacology and Toxicology
Identifiers
urn:nbn:se:su:diva-98958 (URN)10.1002/bmc.2946 (DOI)000328324100015 ()
Note

AuthorCount: 6

Available from: 2014-01-10 Created: 2014-01-10 Last updated: 2023-12-05Bibliographically approved
Holmgren, E., Ek, S. & Colmsjö, A. (2012). Extraction of explosives from soil followed by gas chromatography-mass spectrometry analysis with negative chemical ionization. Journal of Chromatography A, 1222, 109-115
Open this publication in new window or tab >>Extraction of explosives from soil followed by gas chromatography-mass spectrometry analysis with negative chemical ionization
2012 (English)In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1222, p. 109-115Article in journal (Refereed) Published
Abstract [en]

A new, simple and accurate method for extraction of explosives from soil was developed and validated. The method includes one hour gentle extraction of compounds from soil in acetonitrile:dichloromethane 50:50 at 30 degrees C. Further analysis was made with GC-MS using cool on-column injection and negative chemical ionization. The method increased the recovery of the more volatile products, generated higher accuracy and was extensively time-saving compared to the conventional EPA (US Environmental Protection Agency) 8330 method. Applications are demonstrated on commercial reference materials.

Keywords
Explosives, GC-MS, Extraction, Soil, Chemical ionization
National Category
Analytical Chemistry
Identifiers
urn:nbn:se:su:diva-76320 (URN)10.1016/j.chroma.2011.12.014 (DOI)000300115700013 ()
Note
3Available from: 2012-05-15 Created: 2012-05-10 Last updated: 2022-02-24Bibliographically approved
Larson, T., Östman, C. & Colmsjö, A. (2011). An automated multidimensional preparative gas chromatographic system for isolation and enrichment of trace amounts of xenon from ambient air. Analytical and Bioanalytical Chemistry, 400(2), 449-458
Open this publication in new window or tab >>An automated multidimensional preparative gas chromatographic system for isolation and enrichment of trace amounts of xenon from ambient air
2011 (English)In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 400, no 2, p. 449-458Article in journal (Refereed) Published
Abstract [en]

The monitoring of radioactive xenon isotopes is one of the principal methods for the detection of nuclear explosions in order to identify clandestine nuclear testing. In this work, a miniaturized, multiple-oven, six-column, preparative gas chromatograph was constructed in order to isolate trace quantities of radioactive xenon isotopes from ambient air, utilizing nitrogen as the carrier gas. The multidimensional chromatograph comprised preparative stainless steel columns packed with molecular sieves, activated carbon, and synthetic carbon adsorbents (e.g., AnasorbA (R)-747 and CarbosphereA (R)). A combination of purification techniques-ambient adsorption, thermal desorption, back-flushing, thermal focusing, and heart cutting-was selectively optimized to produce a well-defined xenon peak that facilitated reproducible heart cutting and accurate quantification. The chromatographic purification of a sample requires approximately 4 h and provides complete separation of xenon from potentially interfering components (such as water vapor, methane, carbon dioxide, and radon) with recovery and accuracy close to 100%. The preparative enrichment process isolates and concentrates a highly purified xenon gas fraction that is suitable for subsequent ultra-low-level gamma-, /gamma-spectroscopic or high-resolution mass spectrometric measurement (e.g., to monitor the gaseous fission products of nuclear explosions at remote locations). The Xenon Processing Unit is a free-standing, relatively lightweight, and transportable system that can be interfaced to a variety of sampling and detection systems. It has a relatively inexpensive, rugged, and compact modular (19-inch rack) design that provides easy access to all parts for maintenance and has a low power requirement.

Keywords
Preparative enrichment of xenon, Noble gas, Radioxenon, Stable xenon, Radon separation, Carbon adsorbents, CTBT, IMS, Nuclear safeguards
National Category
Chemical Sciences
Identifiers
urn:nbn:se:su:diva-69082 (URN)10.1007/s00216-011-4754-4 (DOI)000289000300018 ()
Note
authorCount :3Available from: 2012-01-10 Created: 2012-01-10 Last updated: 2022-02-24Bibliographically approved
Thewalim, Y., Sadiktsis, I. & Colmsjö, A. (2011). Comparing columns for gas chromatography with the two-parameter model for retention prediction. Journal of Chromatography A, 1218(31), 5305-5310
Open this publication in new window or tab >>Comparing columns for gas chromatography with the two-parameter model for retention prediction
2011 (English)In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1218, no 31, p. 5305-5310Article in journal (Refereed) Published
Abstract [en]

The retention times of selected compounds in temperature programmed gas chromatography were predicted using a two-parameter model, on the basis of thermodynamic data obtained from isothermal runs on seven capillary columns, primarily substituted with 5% diphenylsiloxane. The scope for using thermodynamic data obtained from isothermal runs on one column to optimize separation on a different column or a different instrument setup was investigated. Additionally, the predictive utility of thermodynamic data obtained using a DB-5 column that had been in use for three years was compared to that of a new column of the same model. It was found that satisfactory separation could be achieved on one capillary column or instrument setup on the basis of thermodynamic data obtained using a different column or instrument set-up.

Keywords
Gas chromatography, Prediction, Retention time, PCA score plot, Aged column, Thermodynamic properties
National Category
Natural Sciences
Identifiers
urn:nbn:se:su:diva-68295 (URN)10.1016/j.chroma.2011.05.082 (DOI)000293432200035 ()
Note

authorCount :3

Available from: 2012-01-15 Created: 2012-01-03 Last updated: 2022-02-24Bibliographically approved
Thewalim, Y., Bruno, O. & Colmsjö, A. (2011). Study of the chromatographic behaviour of selected alcohols and amines. Analytical and Bioanalytical Chemistry, 399(3), 1335-1345
Open this publication in new window or tab >>Study of the chromatographic behaviour of selected alcohols and amines
2011 (English)In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 399, no 3, p. 1335-1345Article in journal (Refereed) Published
Abstract [en]

The gas chromatographic behavior of selected linear and non-linear alcohols and amines was investigated using four capillary columns containing phenyl substitution levels of 0%, 5%, and 50% and 50% cyanopropyl substitution. In a previous study, the positions of specific compounds inside the capillary column were iteratively modeled using only two thermodynamic parameters (ΔH and ΔS). The present study addresses the validation of the two-parameter model for retention time prediction for selected alcohols and amines using thermodynamic data obtained from as few as two data points. The difference between predicted and observed retention times under different temperature conditions was generally less than 1% of the experimental value and the predicted order of elution was correct in the used model.

Keywords
Gas chromatography, Alcohols, Amines, Prediction, Retention time
National Category
Analytical Chemistry
Research subject
Analytical Chemistry
Identifiers
urn:nbn:se:su:diva-54987 (URN)10.1007/s00216-010-4418-9 (DOI)000286599100033 ()
Available from: 2011-02-23 Created: 2011-02-23 Last updated: 2022-02-24Bibliographically approved
Tollbäck, J., Isetun, S., Colmsjö, A. & Nilsson, U. (2010). Dynamic non-equilibrium SPME combined with GC, PICI, and ion trap MS for determination of organophosphate esters in air. Analytical and Bioanalytical Chemistry, 396(2), 839-844
Open this publication in new window or tab >>Dynamic non-equilibrium SPME combined with GC, PICI, and ion trap MS for determination of organophosphate esters in air
2010 (English)In: Analytical and Bioanalytical Chemistry, ISSN 1618-2642, E-ISSN 1618-2650, Vol. 396, no 2, p. 839-844Article in journal (Refereed) Published
Abstract [en]

Methodology for time-weighted average (TWA) air measurements of semivolatile organophosphate triesters, widely used flame-retardants and plasticizers, and common indoor pollutants is presented. Dynamic non-equilibrium solid-phase microextraction (SPME) for air sampling, in combination with GC/PICI and ion trap tandem MS, yields a fast, almost solvent-free method with low detection limits. Methanol was used as reagent gas for PICI, yielding stable protonated molecules and few fragments. A field sampler, in which a pumped airflow over three polydimethylsiloxane (PDMS) 100-μm fibers in series was applied, was constructed, evaluated, and used for the measurements. The method LODs were in the range 2–26 ng m−3 for a sampling period of 2 h. The uptake on the SPME fibers was shown to be about five times faster for triphenyl phosphate compared to the other investigated organophosphate esters, most likely due to more lipophilic properties of the aromatic compound. The boundary layer for triphenyl phosphate when using a 100-µm PDMS sorbent was determined to 0.08 mm at a linear air velocity of 34 cm s−1. Five different organophosphate triesters were detected in air from a laboratory and a lecture hall, at concentrations ranging from 7 ng m−3 up to 2.8 μg m−3.

Place, publisher, year, edition, pages
Berlin: Springer, 2010
Keywords
Organophosphate triesters, SPME, Non-equilibrium, Dynamic air sampling, PICI, GC/MS/MS
National Category
Natural Sciences
Identifiers
urn:nbn:se:su:diva-34673 (URN)10.1007/s00216-009-3221-y (DOI)
Available from: 2010-01-11 Created: 2010-01-11 Last updated: 2022-02-25Bibliographically approved
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