| 1. |
- Abdel-Rehim, Abbi, et al.
(författare)
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Dried saliva spot as a sampling technique for saliva samples
- 2014
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Ingår i: BMC Biomedical chromotography. - : Wiley. - 0269-3879 .- 1099-0801. ; 28:6, s. 875-877
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Tidskriftsartikel (refereegranskat)abstract
- For the first time, dried saliva spot (DSS) was used as a sampling technique for saliva samples. In the DSS technique 50 L of saliva was collected on filter paper and the saliva was then extracted with an organic solvent. The local anesthetic lidocaine was used as a model compound, which was determined in the DSS using liquid chromatography and mass spectrometry. The results obtained for the determination of lidocaine in saliva using DSS were compared with those from a previous study using a microextraction by packed sorbent syringe as the sampling method for saliva. This study shows that DSS can be used for the analysis of saliva samples. The method is promising and very easy in terms of sampling and extraction procedures. The results from this study are in good agreement with those from our previous work on the determination of lidocaine in saliva. DSS can open a new dimension in the saliva handling process in terms of sampling, storing and transport.
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| 2. |
- Abdel-Rehim, Abbi, et al.
(författare)
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Evaluation of microextraction by packed sorbent and micro-liquid chromatography-tandem mass spectrometry as a green approach in bioanalysis
- 2013
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Ingår i: BMC Biomedical chromotography. - : Wiley. - 0269-3879 .- 1099-0801. ; 27:10, s. 1225-1233
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Tidskriftsartikel (refereegranskat)abstract
- In this study the use of micro-liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was investigated in routine bioanalysis application for separation and quantification of pro-drug AZD6319 (developed for aldezheimer treatment). Microextraction by packed sorbent (MEPS) was used as sample clean-up method. The focus of this study was put on the evaluation of the usability of smaller column diameters such as 1.0 and 0.3mm instead of 2.1mm in bioanalysis application to reduce solvent consumption and sample volumes. Solvent consumption was reduced by 80% when a 1.0mm column was used compared with 2.1mm column. Robustness of the micro-columns in terms of accuracy and precision was investigated. The application of LC-MS/MS for the quantitative analysis of AZD6319 in plasma samples showed good selectivity, accuracy and precision. The coefficients of determination (R-2) were >0.998 for all runs using plasma samples on the studied micro-columns. The inter-day accuracy values for quality control samples ranged from 99 to 103% and from 96 to 105% for 0.3x50mm and 1.0x50mm columns, respectively. The inter-day precision values ranged from 4.0 to 9.0% and from 4.0 to 8.0% for 0.3x50 and 1.0x50mm columns, respectively. In addition the sensitivity was increased by three times using a 1.0mm column compared with 2.1mm. Furthermore, robustness of the micro-columns from different manufacturers was investigated.
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| 3. |
- Abdel Rehim, Abbi, et al.
(författare)
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Screening and determination of drugs in human saliva utilizing microextraction by packed sorbent and liquid chromatography-tandem mass spectrometry
- 2013
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Ingår i: BMC Biomedical chromotography. - : Wiley. - 0269-3879 .- 1099-0801. ; 27:9, s. 1188-1191
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Tidskriftsartikel (refereegranskat)abstract
- This study presents a new method for collecting and handling saliva samples using an automated analytical microsyringe and microextraction by packed syringe (MEPS). The screening and determination of lidocaine in human saliva samples utilizing MEPS and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were carried out. An exact volume of saliva could be collected. The MEPS C-8-cartridge could be used for 50 extractions before it was discarded. The extraction recovery was about 60%. The pharmacokinetic curve of lidocaine in saliva using MEPS-LC-MS/MS is reported.
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| 4. |
- Abohalaka, Reshed, et al.
(författare)
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The effects of systemic and local fatty acid amide hydrolase and monoacylglycerol lipase inhibitor treatments on the metabolomic profile of lungs.
- 2022
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Ingår i: Biomedical chromatography : BMC. - : Wiley. - 1099-0801 .- 0269-3879. ; 36:1
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Tidskriftsartikel (refereegranskat)abstract
- The contribution of the endocannabinoid system to both physiology and pathological processes in the respiratory system makes it a promising target for inflammatory airway diseases. Previously, we have shown that increasing the tissue endocannabinoid levels by fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) inhibitors can prevent airway inflammation and hyperreactivity. In this study, the changes in the levels of major metabolites of endocannabinoids by systemic and local FAAH or MAGL inhibitor treatments were evaluated. Mice were treated with either the FAAH inhibitor URB597 or the MAGL inhibitor JZL184 by local (intranasal) or systemic (intraperitoneal) application. Bronchoalveolar lavage (BAL) fluids and lungs were isolated afterward in order to perform histopathological and metabolomic analyses. There were no significant histopathological changes in the lungs and neutrophil, and macrophage and lymphocyte numbers in BAL fluid were not altered after local and systemic treatments. However, GC-MS-based metabolomics profile allowed us to identify 102 metabolites in lung samples, among which levels of 75 metabolites were significantly different from the control. The metabolites whose levels were changed by treatments were mostly related to the endocannabinoid system and energy metabolism. Therefore, these changes may contribute to the anti-inflammatory effects of URB597 and JZL184 treatments in mice.
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| 5. |
- Alizadeh, R., et al.
(författare)
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Synthesis of Depo-Medrol-chitosan hydrogel as new drug slow-release appliance and investigation of release kinetics by high-performance liquid chromatography
- 2016
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Ingår i: Biomedical Chromatography. - : Wiley. - 1099-0801 .- 0269-3879. ; 30:9, s. 1346-1353
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Tidskriftsartikel (refereegranskat)abstract
- The present study deals with preparation and optimization of a novel chitosan hydrogel-based matrix by suspension cross-linking method for controlled release of Depo-Medrol. The controlled release of Depo-Medrol for effective Rheumatoid arthritis disease has become an imperative field in the drug delivery system. In this context, it was intended to optimize loading circumstances by experimental design and also study the release kinetics of Depo-Medrol entrapped in the chitosan matrix in order to obtain maximal efficiency for drug loading. The optimum concentrations of chitosan (2.5g), glutaraldehyde (3.05L) and Depo-Medrol (0.1mg) were set up to achieve the highest value of drug loaded and the most sustained release from the chitosan matrix. In vitro monitoring of drug release kinetic using high-performance liquid chromatography showed that 73% of the Depo-Medrol was released within 120min, whereas remained drug was released during the next 67h. High correlation between first-order and Higuchi's kinetic models indicates a controlled diffusion of Depo-Medrol through the surrounding media. Moreover, recovery capacity >82% and entrapment efficiency of 58-88% were achieved under optimal conditions. Therefore, the new synthesized Depo Medrol-chitosan is an applicable appliance for therapy by slow release mechanism.
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| 6. |
- Ashri, Nadia Y., et al.
(författare)
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micMicroextraction by packed sorbent and liquid chromatography-tandem mass spectrometry as a tool for quantification of peptides in plasma samples : determination of sensory neuron-specific receptors agonist BAM8-22 and antagonist BAM22-8 in plasma samples
- 2013
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Ingår i: BMC Biomedical chromotography. - : Wiley. - 0269-3879 .- 1099-0801. ; 27:3, s. 396-403
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Tidskriftsartikel (refereegranskat)abstract
- Microextraction by packed sorbent (MEPS) is a miniaturized, solid-phase extraction (SPE) technique that works online with gas chromatography (GC) and liquid chromatography (LC). Not only is the automation process with MEPS advantageous, but the much smaller volumes of the samples, solvents and dead space in the system also provide other significant advantages such as the speed and the simplicity of the sample preparation process. In this study MEPS has been evaluated for quantification of sensory neuron-specific receptors agonist (BAM8-22). Owing to the instability of BAMs, the focus was on fast extraction and determination of the peptide online using LC-MS/MS. Sorbents such as C2, C8 and ENV+ (hydroxylated polystyrenedivinylbenzene copolymer) were investigated in the present study. MEPS-C8 gave the best results compared with C2 and ENV and it was used for the method validation. The calibration curve was obtained within the concentration range of 20.03045nmol/L in plasma. The regression correlation coefficients for plasma samples were 0.99 for all runs (n=6). The between-batch accuracy and precision for BAM8-22 ranged from 13 to 2.0% and from 4.0 to 14%, respectively. Additionally, the accuracy and precision for BAM22-8 ranged from 13 to 7.0% and from 3.0 to 12%, respectively. The present method was used for pharmacokinetic studies for BAMs in plasma samples.
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| 7. |
- Aslıyüce, Sevgi, et al.
(författare)
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Combined protein A imprinting and cryogelation for production of spherical affinity material
- 2019
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Ingår i: Biomedical Chromatography. - : Wiley. - 0269-3879 .- 1099-0801. ; 33:10
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Tidskriftsartikel (refereegranskat)abstract
- Cryogels have been demonstrated to be efficient when applied for protein isolation. Owing to their macroporous structure, cryogels can also be used for treating particle-containing material, e.g. cell homogenates. Another challenging development in protein purification technology is the use of molecularly imprinted polymers (MIPs). These MIPs are robust and can be used repeatedly. The paper presents a new technology that combine the formation of cryogel beads concomitantly with making imprints of a protein. Protein A was chosen as the print molecule which was also be the target in the purification step. The present paper describes a new method to produce protein-imprinted cryogel beads. The protein-imprinted material was characterized and the separation properties were evaluated with regard to both the target protein and whole cells with target protein exposed on the cell surface. The maximum protein A adsorption was 18.1 mg/g of wet cryogel beads. The selectivity coefficient of protein A-imprinted cryogel beads for protein A was 5.44 and 12.56 times greater than for the Fc fragment of IgG and protein G, respectively.
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| 8. |
- Bienvenu, Emile, et al.
(författare)
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A rapid and selective HPLC-UV method for the quantitation of efavirenz in plasma from patients on concurrent HIV/AIDS and tuberculosis treatments.
- 2013
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Ingår i: Biomedical chromatography : BMC. - : Wiley. - 1099-0801 .- 0269-3879. ; 27:11, s. 1554-9
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Tidskriftsartikel (refereegranskat)abstract
- Owing to heterogeneity in therapeutic response, efavirenz is of research and clinical interest. There is a need to quantitate it using noncostly and selective methods. A method for efavirenz quantitation in plasma containing HIV and tuberculosis drugs was developed. Chromatographic separation was carried out using a C18 column. The mobile phase consisted of 0.1% formic acid and acetonitrile, and was pumped at a flow rate of 0.3 mL/min. Efavirenz and ritonavir (internal standard) were monitored at 247 nm. Plasma proteins were precipitated by centrifugation. The analysis time was 6 min. The response was linear (r=0.9997). The accuracy ranged between 98 and 115% (intraday) and between 99 and 117% (interday). The precision ranged from 1.670 to 4.087% (intraday) and from 3.447 to 13.347% (interday). Recovery ranged from 98 to 132%. Stability ranged between 99 and 123%. The selectivity was proven by analysis of drugs used for the management of HIV/AIDS and tuberculosis. Plasma sample analysis showed an efavirenz retention time of 5.57 min and a peak plasma concentration of 2.4 µg/mL occurring at 2 h. This method is rapid and selective, and thus suitable for monitoring efavirenz in patients with HIV/AIDS alone or co-infected with tuberculosis in a less resourced setting.
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| 9. |
- Daryanavard, S. M., et al.
(författare)
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Recent applications of microextraction sample preparation techniques in biological samples analysis
- 2021
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Ingår i: BMC Biomedical chromotography. - : Wiley. - 0269-3879 .- 1099-0801. ; 35:7
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Tidskriftsartikel (refereegranskat)abstract
- Analysis of biological samples is affected by interfering substances with chemical properties similar to those of the target analytes, such as drugs. Biological samples such as whole blood, plasma, serum, urine and saliva must be properly processed for separation, purification, enrichment and chemical modification to meet the requirements of the analytical instruments. This causes the sample preparation stage to be of undeniable importance in the analysis of such samples through methods such as microextraction techniques. The scope of this review will cover a comprehensive summary of available literature data on microextraction techniques playing a key role for analytical purposes, methods of their implementation in common biological samples, and finally, the most recent examples of application of microextraction techniques in preconcentration of analytes from urine, blood and saliva samples. The objectives and merits of each microextration technique are carefully described in detail with respect to the nature of the biological samples. This review presents the most recent and innovative work published on microextraction application in common biological samples, mostly focused on original studies reported from 2017 to date. The main sections of this review comprise an introduction to the microextraction techniques supported by recent application studies involving quantitative and qualitative results and summaries of the most significant, recently published applications of microextracion methods in biological samples. This article considers recent applications of several microextraction techniques in the field of sample preparation for biological samples including urine, blood and saliva, with consideration for extraction techniques, sample preparation and instrumental detection systems.
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| 10. |
- Daryanavard, Seyed, et al.
(författare)
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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
- 2013
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Ingår i: BMC Biomedical chromotography. - : Wiley-Blackwell. - 0269-3879 .- 1099-0801. ; 27:11, s. 1418-1488
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Tidskriftsartikel (refereegranskat)abstract
- 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
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