TY  - JOUR
AU  - Kumrić, Ksenija
AU  - Vladisavljević, Goran T.
AU  - Đorđević, Jelena S.
AU  - Jonsson, Jan Ake
AU  - Trtić-Petrović, Tatjana M.
PY  - 2012
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/5044
AB  - In this study, the mass transport resistance in liquid-phase microextraction (LPME) in a single hollow fiber was investigated. A mathematical model has been developed for the determination of the overall mass transfer coefficient based on the acceptor phase in an unsteady state. The overall mass transfer coefficient in LPME in a single hollow fiber has been estimated from time-dependent concentration of extracted analyte in the acceptor phase while maintaining a constant analyte concentration in the donor phase. It can be achieved either using a high volume of donor to acceptor phase ratio or tuning the extraction conditions to obtain a low-enrichment factor, so that the analyte concentration in the sample is not significantly influenced by the mass transfer. Two extraction systems have been used to test experimentally the developed model: the extraction of Lu(III) from a buffer solution and the extraction of three local anesthetics from a buffer or plasma solution. The mass transfer resistance, defined as a reciprocal values of the mass transfer coefficient, was found to be 1.2 x 103 cm-1 min for Lu(III) under optimal conditions and from 1.96 to 3.3 x 103 cm-1 min for the local anesthetics depending on the acceptor pH and the hydrophobicity of the drug.
T2  - Journal of Separation Science
T1  - Mass transfer resistance in a liquid-phase microextraction employing a single hollow fiber under unsteady-state conditions
VL  - 35
IS  - 18
SP  - 2390
EP  - 2398
DO  - 10.1002/jssc.201200497
ER  - 

@article{
author = "Kumrić, Ksenija and Vladisavljević, Goran T. and Đorđević, Jelena S. and Jonsson, Jan Ake and Trtić-Petrović, Tatjana M.",
year = "2012",
abstract = "In this study, the mass transport resistance in liquid-phase microextraction (LPME) in a single hollow fiber was investigated. A mathematical model has been developed for the determination of the overall mass transfer coefficient based on the acceptor phase in an unsteady state. The overall mass transfer coefficient in LPME in a single hollow fiber has been estimated from time-dependent concentration of extracted analyte in the acceptor phase while maintaining a constant analyte concentration in the donor phase. It can be achieved either using a high volume of donor to acceptor phase ratio or tuning the extraction conditions to obtain a low-enrichment factor, so that the analyte concentration in the sample is not significantly influenced by the mass transfer. Two extraction systems have been used to test experimentally the developed model: the extraction of Lu(III) from a buffer solution and the extraction of three local anesthetics from a buffer or plasma solution. The mass transfer resistance, defined as a reciprocal values of the mass transfer coefficient, was found to be 1.2 x 103 cm-1 min for Lu(III) under optimal conditions and from 1.96 to 3.3 x 103 cm-1 min for the local anesthetics depending on the acceptor pH and the hydrophobicity of the drug.",
journal = "Journal of Separation Science",
title = "Mass transfer resistance in a liquid-phase microextraction employing a single hollow fiber under unsteady-state conditions",
volume = "35",
number = "18",
pages = "2390-2398",
doi = "10.1002/jssc.201200497"
}

Kumrić, K., Vladisavljević, G. T., Đorđević, J. S., Jonsson, J. A.,& Trtić-Petrović, T. M.. (2012). Mass transfer resistance in a liquid-phase microextraction employing a single hollow fiber under unsteady-state conditions. in Journal of Separation Science, 35(18), 2390-2398.
https://doi.org/10.1002/jssc.201200497

Kumrić K, Vladisavljević GT, Đorđević JS, Jonsson JA, Trtić-Petrović TM. Mass transfer resistance in a liquid-phase microextraction employing a single hollow fiber under unsteady-state conditions. in Journal of Separation Science. 2012;35(18):2390-2398.
doi:10.1002/jssc.201200497 .

Kumrić, Ksenija, Vladisavljević, Goran T., Đorđević, Jelena S., Jonsson, Jan Ake, Trtić-Petrović, Tatjana M., "Mass transfer resistance in a liquid-phase microextraction employing a single hollow fiber under unsteady-state conditions" in Journal of Separation Science, 35, no. 18 (2012):2390-2398,
https://doi.org/10.1002/jssc.201200497 . .

TY  - JOUR
AU  - Barri, Thaer
AU  - Trtić-Petrović, Tatjana M.
AU  - Karlsson, Michael
AU  - Jonsson, Jan Ake
PY  - 2008
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/3525
AB  - The technique equilibrium sampling through membrane (ESTM) was extended to measuring the free drug concentration in solutions of drug and protein. Bjerrum and Scatchard plots were employed for characterizing individual drug binding to pure human blood proteins. Four drugs were investigated as a model system: fluvoxamine and ropivacaine which dominantly bind to alpha-acid glycoprotein (AGP), and R,S-ibuprofen and S-ketoprofen which highly bind to human serum albumin (HSA). The level of drug binding to AGP and HSA relied on drug and protein concentrations. Bjerrum and Scatchard plots revealed high affinity constants (K-a) at low protein concentration. Both Bjerrum and Scatchard plots of fluvoxamine and ne binding to AGP showed one specific binding site (n(1) = 1) with ropivacaine K-a value close to 5 ropivacaine K-a value close to 5 times higher than the K-a of fluvoxamine at 22.9 mu M AGP concentration. Bjerrum plots of ketoprofen and ibuprofen gave total number of binding sites or bound molecules of 6-7, which did not depend on the drug or protein concentration. Scatchard plots of ketoprofen and ibuprofen exhibited two binding sites (n(1) and n(2)) at 0.15 mu M and 0.75 mu M HSA concentrations. On one hand, at 0.15 mu M HSA, ketoprofen and ibuprofen were bound to site I at n(1) = 1.2 and n(1) = 1.0, respectively. However, at 0.75 mu M HSA, ketoprofen and ibuprofen were bound to site I at n(1) = 1.2 and n(1) = 1.9, respectively. On the other hand, site 11, at 0.15 mu M HSA, interacted with ketoprofen and ibuprofen at n(2) = 5.6 and 6.7, respectively. However, at 0.75 mu M HSA, site II interacted with ketoprofen at n(2) = 7.4 and ibuprofen at n(2) = 6.2. It would be concluded that, upon mixing ketoprofen and ibuprofen in a HSA solution, a ketoprofen-ibuprofen interaction would most likely occur at site II in HSA. (c) 2008 Elsevier B.V. All rights reserved.
T2  - Journal of Pharmaceutical and Biomedical Analysis
T1  - Characterization of drug-protein binding process by employing equilibrium sampling through hollow-fiber supported liquid membrane and Bjerrum and Scatchard plots
VL  - 48
IS  - 1
SP  - 49
EP  - 56
DO  - 10.1016/j.jpba.2008.04.030
ER  - 

@article{
author = "Barri, Thaer and Trtić-Petrović, Tatjana M. and Karlsson, Michael and Jonsson, Jan Ake",
year = "2008",
abstract = "The technique equilibrium sampling through membrane (ESTM) was extended to measuring the free drug concentration in solutions of drug and protein. Bjerrum and Scatchard plots were employed for characterizing individual drug binding to pure human blood proteins. Four drugs were investigated as a model system: fluvoxamine and ropivacaine which dominantly bind to alpha-acid glycoprotein (AGP), and R,S-ibuprofen and S-ketoprofen which highly bind to human serum albumin (HSA). The level of drug binding to AGP and HSA relied on drug and protein concentrations. Bjerrum and Scatchard plots revealed high affinity constants (K-a) at low protein concentration. Both Bjerrum and Scatchard plots of fluvoxamine and ne binding to AGP showed one specific binding site (n(1) = 1) with ropivacaine K-a value close to 5 ropivacaine K-a value close to 5 times higher than the K-a of fluvoxamine at 22.9 mu M AGP concentration. Bjerrum plots of ketoprofen and ibuprofen gave total number of binding sites or bound molecules of 6-7, which did not depend on the drug or protein concentration. Scatchard plots of ketoprofen and ibuprofen exhibited two binding sites (n(1) and n(2)) at 0.15 mu M and 0.75 mu M HSA concentrations. On one hand, at 0.15 mu M HSA, ketoprofen and ibuprofen were bound to site I at n(1) = 1.2 and n(1) = 1.0, respectively. However, at 0.75 mu M HSA, ketoprofen and ibuprofen were bound to site I at n(1) = 1.2 and n(1) = 1.9, respectively. On the other hand, site 11, at 0.15 mu M HSA, interacted with ketoprofen and ibuprofen at n(2) = 5.6 and 6.7, respectively. However, at 0.75 mu M HSA, site II interacted with ketoprofen at n(2) = 7.4 and ibuprofen at n(2) = 6.2. It would be concluded that, upon mixing ketoprofen and ibuprofen in a HSA solution, a ketoprofen-ibuprofen interaction would most likely occur at site II in HSA. (c) 2008 Elsevier B.V. All rights reserved.",
journal = "Journal of Pharmaceutical and Biomedical Analysis",
title = "Characterization of drug-protein binding process by employing equilibrium sampling through hollow-fiber supported liquid membrane and Bjerrum and Scatchard plots",
volume = "48",
number = "1",
pages = "49-56",
doi = "10.1016/j.jpba.2008.04.030"
}

Barri, T., Trtić-Petrović, T. M., Karlsson, M.,& Jonsson, J. A.. (2008). Characterization of drug-protein binding process by employing equilibrium sampling through hollow-fiber supported liquid membrane and Bjerrum and Scatchard plots. in Journal of Pharmaceutical and Biomedical Analysis, 48(1), 49-56.
https://doi.org/10.1016/j.jpba.2008.04.030

Barri T, Trtić-Petrović TM, Karlsson M, Jonsson JA. Characterization of drug-protein binding process by employing equilibrium sampling through hollow-fiber supported liquid membrane and Bjerrum and Scatchard plots. in Journal of Pharmaceutical and Biomedical Analysis. 2008;48(1):49-56.
doi:10.1016/j.jpba.2008.04.030 .

Barri, Thaer, Trtić-Petrović, Tatjana M., Karlsson, Michael, Jonsson, Jan Ake, "Characterization of drug-protein binding process by employing equilibrium sampling through hollow-fiber supported liquid membrane and Bjerrum and Scatchard plots" in Journal of Pharmaceutical and Biomedical Analysis, 48, no. 1 (2008):49-56,
https://doi.org/10.1016/j.jpba.2008.04.030 . .