| 1. |
- Carlsson, Henrik, 1987-, et al.
(författare)
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Evaluation of polarity switching for untargeted lipidomics using liquid chromatography coupled to high resolution mass spectrometry
- 2022
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Ingår i: Journal of chromatography. B. - : Elsevier. - 1570-0232 .- 1873-376X. ; 1195
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Tidskriftsartikel (refereegranskat)abstract
- Untargeted lipidomics using liquid chromatography high-resolution mass spectrometry (LC-HRMS) was performed using polarity switching, and in positive and negative polarity separately on the same set of serum samples, and the performances of the methods were evaluated.& nbsp;Polarity switching causes an increase in the cycle time of the HRMS measurements (1.18 s/cycle vs 0.27 s/ cycle), resulting in fewer data points across chromatographic peaks. The coefficient of variation (CV) was on average lower for the added isotopically labelled standards in pooled samples (QC) and patient samples using separate polarities (QC = 5.6%, samples = 12.5%) compared to polarity switching (QC = 8.5%, samples = 13.4%), but the difference was not statistically significant. For the endogenous features measured in the QCs polarity switching resulted in on average significantly higher CVs (3.80 (p = 4.25e-30) and 3.3 percentage points (p = 6.84e-40), for positive and negative modes, respectively) however still acceptable for an untargeted method (mean CVs of 17.9% and 12.2% in positive and negative modes respectively). A slightly larger number of endogenous features were detected using the separate polarities, but the large majority of features (> 95%) were detected with both methodologies. The overlap of features detected in both positive and negative polarities was low (4.1%) demonstrating the importance of using both polarities for untargeted lipidomics. When investigating the effects of a treatment on multiple sclerosis patients it was found that both methodologies gave highly similar biological results, further confirming the applicability of polarity switching.
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| 2. |
- Claeson, Anna-Sara, 1974-, et al.
(författare)
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Feasibility and reliability of measures of bioactive lipids in human plasma and nasal mucosa
- 2022
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Ingår i: Journal of chromatography. B. - : Elsevier. - 1570-0232 .- 1873-376X. ; 1206
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Tidskriftsartikel (refereegranskat)abstract
- Analysis of bioactive lipids is increasingly useful in clinical studies, and there is a need for non-invasive and easy-to-use sampling methods that meet the demands of reliability. Samples that can be taken by a non-professional and that can be taken repeatedly so as to provide more detailed information about the inflammatory process are often desired. In this study, the feasibility of non-invasive sampling of nasal mucosa and saliva for the analysis of bioactive lipid mediators (e.g. oxylipins and endocannabinoids) was evaluated in a pilot study (n = 10). In a second study, the reliability (relative and absolute) of sampling of these lipid mediators derived from nasal mucosa and from plasma was assessed by calculation of the intraclass correlation coefficient and Bland–Altman’s limit of agreement. Samples were taken at the same time of day on two occasions from a cohort of individuals with and without building-related intolerance (n = 37). Nasal mucosa proved to be a suitable matrix for the analysis of bioactive lipids and was therefore included in the study on reliability together with the plasma samples. Relative reliability varied among the identified oxylipins and endocannabinoids. Arachidonic acid derivatives showed generally better reliability. Absolute reliability measures also varied indicating that only a subset of the oxylipins and endocannabinoids were suitable as biomarkers in either nasal mucosa or plasma and should therefore be used with caution for that purpose.
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| 3. |
- Hodek, Ondrej, et al.
(författare)
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Structural elucidation of 3-nitrophenylhydrazine derivatives of tricarboxylic acid cycle acids and optimization of their fragmentation to boost sensitivity in liquid chromatography-mass spectrometry
- 2023
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Ingår i: Journal of Chromatography B. - 1570-0232 .- 1873-376X. ; 1222
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Tidskriftsartikel (refereegranskat)abstract
- Carboxylic acids participate in many metabolic pathways including tricarboxylic acid (TCA) cycle. Therefore, there have been ongoing attempts to develop sensitive liquid chromatography-mass spectrometry methods over the last decades. Derivatization of the carboxylic acids with 3-nitrophenylhydrazine presents a well-established methodology, and yet the derivatized species of polycarboxylic acids and their fragmentation in collision-induced dissociation have not been fully studied before. In our study, we elucidated how annotation of most abundant 3-nitrophenylhydrazine derivatives and optimization of their fragmentation in multiple reaction monitoring can boost the sensitivity, especially for polycarboxylic acids. Finally, the optimized liquid chromatography-tandem mass spectrometry method allowed for low detection limits ranging from 10 pM for 2-oxoglutaric acid to 800 pM for pyruvic acid. All TCA carboxylates were quantified in 20 mu L of human plasma and the targeted method was validated in the same matrix. The same methodology with a modified gradient elution was also applied to untargeted screening of fatty acids by using high-resolution mass spectrometry enabling identification of 29 medium-to long-chain fatty acids in human plasma. The TCA carboxylates were also quantified in 105 of C2C12 mouse myuotube cells grown under different treatments to proof applicability of the methodology to biological studies in a wider sense. However, unfortunately all the TCA carboxylates were also found in the derivatized blanks in substantial amounts, which prevents from using the methodology for quan-tification of the carboxylates in less than 105 cells.
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| 4. |
- Jayantha, J. B. S. K., et al.
(författare)
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A fast ultra performance supercritical fluid chromatography-tandem mass spectrometric method for profiling of targeted phytosterols
- 2023
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Ingår i: Journal of chromatography. B. - : Elsevier. - 1570-0232 .- 1873-376X. ; 1225
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Tidskriftsartikel (refereegranskat)abstract
- Phytosterols are essential structural components of plant cell membranes and possess health-related benefits, including lowering blood cholesterol levels in humans. Numerous analytical methods are being used to profile plant and animal sterols. Chromatography hyphenated to tandem mass spectrometry, is a better option due to its specificity, selectivity, and sensitivity. An ultra-performance supercritical fluid chromatography hyphenated with atmospheric pressure chemical ionization (APCI) tandem mass spectrometric method was developed and eval-uated for fingerprint analysis of seven phytosterols. Mass spectrometry fragmentation behavior was used for phytosterol identification, and multiple reaction monitoring scanning was utilized for phytosterol confirmation, where APCI outperformed superiority in terms of ion intensity, particularly in the production of [M + H-H2O]+ ions rather than [M + H]+ ions. The chromatographic conditions were thoroughly evaluated, and the ionization parameters were optimized as well. In a 3 min. run, the seven phytosterols were separated concurrently. The calibration and repeatability tests were conducted to check the instrument's performance, and the results indicated that all of the phytosterols tested had correlation coefficients (r2) greater than 0.9911 over the con-centration range of 5-5000 ng/mL. The limit of quantification was below 20 ng/mL for all the tested analytes except for stigmasterol and campesterol. The partially validated method was applied for the evaluation of phytosterols in pure coconut oil and palm oil in order to demonstrate its applicability. Total sterols in coconut and palm oils were 126.77 ng/mL and 101.73 ng/mL, respectively. In comparison to earlier methods of phytosterol analysis, the novel method offers a far faster, more sensitive, and more selective analytical process.
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| 5. |
- Motwani, Hitesh V.
(författare)
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DNA as an in vitro trapping agent for detection of bulky genotoxic metabolites
- 2020
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Ingår i: Journal of chromatography. B. - : Elsevier BV. - 1570-0232 .- 1873-376X. ; 1152
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Tidskriftsartikel (refereegranskat)abstract
- The instability of electrophilic reactive metabolites in in vitro metabolism studies makes their accurate analysis challenging. To stabilise the reactive compounds prior to their analysis, different trapping agents, such as thiols, amines and cob(I)alamin, have earlier been tested depending on the metabolites to be analysed and the type of study. In the present work, DNA is introduced as a trapping agent for measuring the formation of bulky electrophilic metabolites. Benzo[a]pyrene (B[a]P), a polycyclic aromatic hydrocarbon (PAH), was used as a model compound in a rat liver S9 metabolic system. Under physiological incubation conditions, B[a]P metabolises to diol epoxide (BPDE) metabolites which were trapped by DNA resulting in the formation of covalently bound DNA adducts. The methodology for analysis of these adducts included extraction of the DNA from the metabolic system, digestion of the DNA to yield nucleosides and analysis of the BPDE-adduct to deoxyguanosine (BPDE-dG) by liquid chromatography coupled to high resolution mass spectrometry (HRMS). The chromatographic conditions in combination with the high mass accuracy data (±3 ppm) was useful in resolving BPDE-dG in its protonated form from the complex set of ions present in the metabolic matrix. The method was validated in terms of sensitivity, specificity, accuracy, precision and recovery, and applied to provide a preliminary estimate of BPDE-dG levels from the metabolism of B[a]P in rat S9. The use of DNA as a trapping agent for in vitro metabolites has a potential to aid in cancer risk assessment procedure of PAHs, for instance, in inter-species comparison of metabolism to reactive metabolites and can be adapted for screening of genotoxic metabolites, e.g., from emerging environmental contaminants.
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| 6. |
- Nassazzi, Winnie, et al.
(författare)
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A novel method for extraction, clean-up and analysis of per- and polyfluoroalkyl substances (PFAS) in different plant matrices using LC-MS/MS
- 2022
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Ingår i: Journal of Chromatography B. - : Elsevier BV. - 1570-0232 .- 1873-376X. ; 1212
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Tidskriftsartikel (refereegranskat)abstract
- Per- and polyfluoroalkyl substances (PFAS) are chemicals of concern due to their persistence, bioaccumulation, and toxic properties. PFAS accumulation in plants poses a risk of human and animal exposure due to consumption of the affected plants, but also allows plants to be used in remediation of PFAS-contaminated soils and groundwater. Therefore, effective extraction, cleanup, and analytical methods for measuring PFAS concentrations in plants are fundamental for research on animal and environmental health. PFAS analysis in plant matrices is complex, due to high matrix interference, and scarcity of methods for analyzing different classes of PFAS. In this study, a simple sample preparation method for PFAS analysis in various plant tissues (leaves, needles, twigs, stems, roots from 10 different species) was developed and validated. Instrumental analysis was performed using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method was optimized considering six different extraction conditions and three different cleanup techniques. Methanol as extraction solvent, combined with 1 g ENVI carb cartridges, showed best performance among all extraction conditions and cleanup techniques tested. Method validation showed good recovery (90–120%), high within-day and between-day precision (<20% relative standard deviation), and low method detection limit (0.04–4.8 ng g−1 dry weight (dw)) for different plant matrices. In tests of the method on soil and different plant tissues of silver birch (Betula pendula) and Norway spruce (Picea abies) at a PFAS-contaminated site, 16 of 24 target PFAS were detected in plants and 17 in soil. ƩPFAS concentration in soil was 43 ng g−1 dw. PFAS distribution in silver birch tissues ranged from 7.1 ng g−1 dw in roots to 64 ng g−1 dw in leaves, and in Norway spruce from 14 ng g−1 dw in roots to 16 ng g−1 dw in needles. This novel method for PFAS analysis in plants can be valuable in future monitoring, process understanding, remediation, and risk assessments.
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| 7. |
- Nilsson Broberg, Malin, et al.
(författare)
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A multivariate data analysis approach for the investigation of in vitro derived metabolites of ACP-105 in comparison with human in vivo metabolites
- 2023
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Ingår i: Journal of chromatography. B. - : Elsevier. - 1570-0232 .- 1873-376X. ; 1231
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Tidskriftsartikel (refereegranskat)abstract
- Selective androgen receptor modulators (SARMs) such as ACP-105 are prohibited in sports due to their anabolic properties. ACP-105 has in previous equine studies shown to undergo extensive metabolism, which makes its metabolite profile important to investigate in humans, since the metabolism is unknown in this species. The aims of the study were to systematically optimize in vitro microsome incubations for improved metabolite yield and to utilize a multivariate data analysis (MVDA) approach to aid the metabolite discovery. Microsomes together with S9 fractions were used at optimal conditions, both with and without phase II additives. Furthermore, the relevance of the in vitro derived metabolites was evaluated as analytical targets in doping control by comparison with results from a human post-administration urine sample collected after a single dose of 100 µg ACP-105. All samples were analyzed with liquid chromatography - Orbitrap mass spectrometry.The use of the systematical optimization and MVDA greatly simplified the search and a total of 18 in vitro metabolites were tentatively identified. The yield of the two main monohydroxylated isomers increased by 24 and 10 times, respectively. In the human urine sample, a total of seven metabolites of ACP-105, formed by a combination of hydroxylations and glucuronic acid conjugations, were tentatively identified. The main metabolites were two monohydroxylated forms that are suggested as analytical targets for human doping control after hydrolysis. All the in vivo metabolites could be detected with the MVDA approach on the in vitro models, demonstrating its usefulness for prediction of the in vivo metabolite profile.
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| 8. |
- Roseboom, Ignace C, et al.
(författare)
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Development and validation of a high-performance liquid chromatography tandem mass spectrometry method for the quantification of the antiparasitic and antifungal drug amphotericin B in human skin tissue.
- 2022
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Ingår i: Journal of chromatography. B. - : Elsevier BV. - 1570-0232 .- 1873-376X. ; 1206
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Tidskriftsartikel (refereegranskat)abstract
- Amphotericin B is an antifungal and antiparasitic drug used in first-line treatment of the parasitic neglected tropical disease leishmaniasis. Liposomal amphotericin B is currently studied for the treatment of cutaneous and post-kala-azar dermal leishmaniasis, where the dermis of the skin is infected with Leishmania parasites. For the optimization of known treatment regimens, accurate target-site concentrations of the drug are required. To date, no assay was available to assess human skin concentrations of amphotericin B. We here present a bioanalytical assay for the quantification of amphotericin B in 4-mm human skin biopsies. Human skin biopsies were homogenized by overnight digestion using collagenase A and were processed afterwards by simple protein precipitation using methanol. Separation and detection were achieved using a Gemini C18 column with slightly acidic chromatographic conditions and a quadrupole - linear ion trap mass spectrometer, respectively. The method was validated in digestion solution over a range of 10-2,000 ng/mL using natamycin as internal standard, with a correlation coefficient (r2) of at least 0.9974. The assay performance, accuracy and precision, were acceptable over the validated range, using international (EMA and FDA) acceptance criteria. In the skin tissue extracts, amphotericin B ion enhancement was observed, however, the internal standard (IS) corrected for this effect hence calibration standards in digestion solvent could be used as a surrogate matrix for the quantification in skin tissue. Sample preparation recoveries were low (around 27%) because of degradation of amphotericin B during digestion and sample preparation processes, albeit highly reproducible, without compromising the accuracy and precision of the method. Using this assay, amphotericin B could be detected and quantified in skin biopsies originating from treated Indian post-kala-azar dermal leishmaniasis patients.
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| 9. |
- Roseboom, Ignace C, et al.
(författare)
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Development and validation of an ultra-high performance liquid chromatography coupled to tandem mass spectrometry method for the quantification of the antileishmanial drug paromomycin in human skin tissue.
- 2022
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Ingår i: Journal of chromatography. B. - : Elsevier. - 1570-0232 .- 1873-376X. ; 1211
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Tidskriftsartikel (refereegranskat)abstract
- Bioanalytical assay development and validation procedures were performed to quantify antiprotozoal drug paromomycin in human skin tissue by ultra-high performance liquid chromatography coupled to tandem mass spectrometry. Paromomycin, an aminoglycoside drug, is administered intra-muscularly and used in the treatment of multiple clinical presentations of the neglected tropical disease leishmaniasis. It is currently studied in the treatment of post-kala-azar dermal leishmaniasis, a disease where the Leishmania parasites divide and reside in the skin. We present a target-site bioanalytical method to accurately quantify paromomycin in human skin tissue, with the clinical purpose of quantifying paromomycin in skin biopsies from post-kala-azar dermal leishmaniasis patients originating from Sudan. Enzymatic digestion using collagenase A incubated at 37 °C overnight was employed as homogenization method to produce skin tissue homogenates. Further sample preparation was performed by protein precipitation using trichloroacetic acid and a dilution step. Final extracts were injected onto a C18 analytical column and isocratic heptafluorobutyric acid ion-pair separation and elution were employed. The chromatography system was coupled to a triple quadrupole mass spectrometer for detection. The method was validated in digestion solution over a linear range from 5 to 1000 ng/mL (r2 ≥ 0.9967) with the assay performance of accuracy and precision within acceptable criteria values as stated by the EMA guidelines. Furthermore, matrix effects were observed in human skin tissue and were corrected by the multiple deuterated paromomycin internal standard. No substantial IS-normalized matrix effect was detected along with relatively high sample preparation recovery. Consequently, digestion solution matrix serving as the preparation of calibration standards can be used as surrogate matrix for human skin tissue, which is convenient given the limited availability of control matrix. Finally, paromomycin was accurately quantified in skin of post-kala-azar dermal leishmaniasis patients originating from clinical trials in Sudan.
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| 10. |
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| 11. |
- Tamburro, Davide, et al.
(författare)
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Analytical performance of a standardized kit for mass spectrometry-based measurements of human glycosaminoglycans
- 2021
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Ingår i: Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences. - : Elsevier BV. - 1570-0232 .- 1873-376X. ; 1177
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Tidskriftsartikel (refereegranskat)abstract
- Glycosaminoglycans (GAGs) are long linear sulfated polysaccharides implicated in processes linked to disease development such as mucopolysaccharidosis, respiratory failure, cancer, and viral infections, thereby serving as potential biomarkers. A successful clinical translation of GAGs as biomarkers depends on the availability of standardized GAG measurements. However, owing to the analytical complexity associated with the quantification of GAG concentration and structural composition, a standardized method to simultaneously measure multiple GAGs is missing. In this study, we sought to characterize the analytical performance of a ultra-high-performance liquid chromatography coupled with triple-quadrupole tandem mass spectrometry (UHPLC-MS/MS)-based kit for the quantification of 17 free GAG disaccharides. The kit showed acceptable linearity, selectivity and specificity, accuracy and precision, and analyte stability in the absolute quantification of 15 disaccharides. In native human samples, here using urine as a reference matrix, the analytical performance of the kit was acceptable for the quantification of CS disaccharides. Intra- and inter-laboratory tests performed in an external laboratory demonstrated robust reproducibility of GAG measurements showing that the kit was acceptably standardized. In conclusion, these results indicated that the UHPLC-MS/MS kit was standardized for the simultaneous measurement of free GAG disaccharides allowing for comparability of measurements and enabling translational research.
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| 12. |
- Truver, Michael, et al.
(författare)
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A sensitive LC-MS/MS method for the quantitation of oxycodone, noroxycodone, 6 alpha-oxycodol, 6 beta-oxycodol, oxymorphone, and noroxymorphone in human blood
- 2021
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Ingår i: Journal of chromatography. B. - : Elsevier. - 1570-0232 .- 1873-376X. ; 1171
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Tidskriftsartikel (refereegranskat)abstract
- The objective of this study was to develop and validate a highly sensitive method for the detection of oxycodone, noroxycodone, 6?-oxycodol, 6?-oxycodol, oxymorphone, and noroxymorphone in blood by liquid chromatography tandem mass spectrometry. The analytes were extracted from blood (0.5 mL) using Bond Elut Certify Solid Phase Extraction columns, evaporated to dryness and reconstituted before analysis was performed on an Acquity UPLC? I-class coupled to a Waters Xevo TQD. Academy Standards Board Standard Practices for Method Development in Forensic Toxicology were used for the validation of this method. The limit of quantitation for all analytes was established at 0.5 ng/mL. Calibration range for noroxymorphone, oxymorphone, 6?-oxycodol and 6?-oxycodol was 0.5?25 ng/mL and 0.5?100 ng/mL for noroxycodone and oxycodone. Precision (2.90?17.3%) and bias studies resulted in a ?15% deviation. There were no interferences observed from internal standard, matrix, or common drugs of abuse. Stability of all analytes at two concentrations at 24, 48, and 72 h in the autosampler did not exceed ?20% difference from the initial T0. Dilution integrity at a ten-fold dilution was acceptable as analyte concentrations ranged between (?18%) of the target concentration. Once validated, the method was used in a pilot dosing study of one male subject after taking a 10 mg immediate release tablet of oxycodone. Blood samples were collected at 0.25, 0.50, 0.75, 1.0, 1.5, 2, 3, 4, 5, 6, 8, 9, and 24 h after ingestion. Oxycodone and noroxycodone both reached Tmax at 1.5 h and had Cmax values of 25.9 and 12.8 ng/mL, respectively. Oxycodone, 6?-oxycodol, and 6?-oxycodol were detectable up to 9 h, while noroxymorphone and noroxycodone were still detected at 24 h.
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| 13. |
- Wegler, Christine, et al.
(författare)
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Simple and rapid quantification of cetirizine, venlafaxine, and O-desmethylvenlafaxine in human breast milk, and metformin in human milk and plasma with UHPLC-MS/MS
- 2022
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Ingår i: Journal of chromatography. B. - : Elsevier. - 1570-0232 .- 1873-376X. ; 1205
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Tidskriftsartikel (refereegranskat)abstract
- The majority of women have health problems that require medication after giving birth. Complications such as allergies, postpartum depression, and diabetes are often treated with drugs such as cetirizine, venlafaxine, and metformin, respectively. These treatments are considered safe during lactation, but information of the transfer of drugs to breast milk and possible effects on the infant is scarce. Therefore, this needs to be systematically investigated in larger populations. To enable the determination of drug transfer, we here describe the validation of two rapid, sensitive, and high-throughput analysis methods for 1) simultaneous quantification of cetirizine, venlafaxine, and O-desmethylvenlafaxine in human breast milk, and 2) metformin in human breast milk and plasma. In both methods, a simple protein precipitation protocol with acetonitrile and benchtop-centrifugation was used prior to compound analysis with liquid-chromatography tandem mass spectrometry. The methods had linear ranges between 0.39 - 194.5 ng/mL for cetirizine, 0.28 - 138.7 ng/mL for venlafaxine, 0.26 - 131.7 ng/mL for O-desmethylvenlafaxine, in milk, and 0.65 - 193.7 ng/mL for metformin in both milk and plasma. Intra-run and inter-run precision and accuracy were < 9% for cetirizine, venlafaxine, and O-desmethylvenlafaxine in milk, and < 7% for metformin in milk and plasma. Cetirizine was measured to median milk concentrations of 13 ng/ mL (range: 0.65 - 65 ng/mL) in 228 donor samples from breast-feeding women.
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| 14. |
- Zheng, Xubin, et al.
(författare)
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Development and validation of a simple LC-MS/MS method for simultaneous determination of moxifloxacin, levofloxacin, prothionamide, pyrazinamide and ethambutol in human plasma
- 2020
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Ingår i: Journal of chromatography. B. - : ELSEVIER. - 1570-0232 .- 1873-376X. ; 1158
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Tidskriftsartikel (refereegranskat)abstract
- Treatment of multidrug-resistant tuberculosis (MDR-TB) is challenging due to high treatment failure rate and adverse drug events. This study aimed to develop and validate a simple LC-MS/MS method for simultaneous measurement of five TB drugs in human plasma and to facilitate therapeutic drug monitoring (TDM) in MDR-TB treatment to increase efficacy and reduce toxicity. Moxifloxacin, levofloxacin, prothionamide, pyrazinamide and ethambutol were prepared in blank plasma from healthy volunteers and extracted using protein precipitation reagent containing trichloroacetic acid. Separation was achieved on an Atlantis T3 column with gradient of 0.1% formic acid in water and acetonitrile. Drug concentrations were determined by dynamic multiple reaction monitoring in positive ion mode on a LC-MS/MS system. The method was validated according to the United States Food and Drug Administration (FDA) guideline for bioanalytical method validation. The calibration curves for moxifloxacin, levofloxacin, prothionamide, pyrazinamide and ethambutol were linear, with the correlation coefficient values above 0.993, over a range of 0.1-5, 0.4-40, 0.2-10, 2-100 and 0.2-10 mg/L, respectively. Validation showed the method to be accurate and precise with bias from 6.5% to 18.3% for lower limit of quantification and -5.8% to 14.6% for LOW, medium (MED) and HIGH drug levels, and with coefficient of variations within 11.4% for all levels. Regarding dilution integrity, the bias was within 7.2% and the coefficient of variation was within 14.9%. Matrix effect (95.7%-112.5%) and recovery (91.4%-109.7%) for all drugs could be well compensated by their isotope-labelled internal standards. A benchtop stability test showed that the degradation of prothionamide was over 15% after placement at room temperature for 72 h. Clinical samples (n = 224) from a cohort study were analyzed and all concentrations were within the analytical range. The signal of prothionamide was suppressed in samples with hemolysis which was solved by sample dilution. As the method is robust and sample preparation is simple, it can easily be implemented to facilitate TDM in programmatic MDR-TB treatment.
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