Application of RP-18 TLC retention data to prediction of transdermal absorption of drugs

Endothelial cell (EC) seeding is postulated as a mechanism of improving patency in small caliber vascular grafts. However the majority of seeded EC are lost within 24 hours of restoration of blood flow in previous canine studies . We postulate that the cells have insufficient time to fully develop their attachment to the graft surface prior to exposure to hemodynamic stress. We allowed EC to incubate on fibronectin-coated ePTFE grafts for four different time periods after seeding and measured EC retention after perfusion in a canine ex vivo shunt circuit.Autologous canine EC, were enzymatically harvested, grown to confluence, and labeled with 30 μCi 111 Indium-oxine/80 cm 2 flask. Four groups of 5 cm x 4 mm ID ePTFE vascular prostheses were coated with 1.5 μg/cm.2 human fibronectin, and seeded with 1.5 x 105 EC/ cm.2. After seeding grafts in Group 1 were incubated in complete growth medium for 90 minutes, Group 2 were incubated for 24 hours, Group 3 for 72 hours and Group 4 for 6 days. Grafts were then placed in the canine ex vivo circuit, constructed between femoral artery and vein, and subjected to blood flow of 75 ml per minute for 6 hours. Continuous counting of γ-activity was made possible by placing the seeded graft inside the γ-counter detection crystal for the duration of perfusion. EC retention data after 30 minutes, 2 hours and 6 hours of flow are shown in the table.

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Theoretical Interpretation of High-Performance Chromatographic Data for a Heterogeneous Series of Compounds

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19920033 ◽

1992 ◽

Vol 57 (1) ◽

pp. 33-45

Author(s):

Vladimír Jakuš

Keyword(s):

Experimental Data ◽

High Performance ◽

Theoretical Interpretation ◽

Retention Data ◽

Theoretical Evaluation ◽

New Approach ◽

Free Energy Of Solvation ◽

Rp Hplc ◽

Mobile Phases ◽

Reversed Phases

A new approach to theoretical evaluation of the Gibbs free energy of solvation was applied for estimation of retention data in high-performance liquid chromatography on reversed phases (RP-HPLC). Simple and improved models of stationary and mobile phases in RP-HPLC were employed. Statistically significant correlations between the calculated and experimental data were obtained for a heterogeneous series of twelve compounds.

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Correlations between retention data of polycyclic aromatic hydrocarbons in micellar liquid chromatography and several molecular descriptors

Fresenius Journal of Analytical Chemistry ◽

10.1007/bf00323003 ◽

1993 ◽

Vol 345 (12) ◽

pp. 748-752 ◽

Cited By ~ 16

Author(s):

M. A. Rodr�guez-Delgado ◽

M. J. S�nchez ◽

V. Gonz�lez ◽

F. Garc�a-Montelongo

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Liquid Chromatography ◽

Aromatic Hydrocarbons ◽

Molecular Descriptors ◽

Micellar Liquid Chromatography ◽

Retention Data ◽

Polycyclic Aromatic

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Transdermal absorption of active substances from cosmetic vehicles

Journal of Cosmetic Dermatology ◽

10.1111/jocd.12873 ◽

2019 ◽

Vol 18 (5) ◽

pp. 1410-1415 ◽

Cited By ~ 1

Author(s):

Jana Pavlačková ◽

Pavlína Egner ◽

Jana Polašková ◽

Jarmila Hojerová ◽

Lucie Pinďáková ◽

...

Keyword(s):

Transdermal Absorption ◽

Active Substances

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Prediction of retention data when using incremental multiple development techniques

Chromatographia ◽

10.1007/bf02505586 ◽

1997 ◽

Vol 45 (1) ◽

pp. 369-372 ◽

Cited By ~ 8

Author(s):

B. Szabady ◽

M. Ruszinkó ◽

Sz. Nyiredy

Keyword(s):

Retention Data ◽

Prediction Of Retention

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Gradient HPLC in the determination of drug lipophilicity and acidity

Pure and Applied Chemistry ◽

10.1351/pac200173091465 ◽

2001 ◽

Vol 73 (9) ◽

pp. 1465-1475 ◽

Cited By ~ 31

Author(s):

Roman Kaliszan ◽

Piotr Haber ◽

Tomasz Baczek ◽

Danuta Siluk

Keyword(s):

Mobile Phase ◽

High Performance ◽

Standard Procedure ◽

Gradient Elution ◽

Log P ◽

Retention Data ◽

Organic Modifier ◽

Wide Range ◽

Aqueous Component ◽

Initial Ph

The linear-solvent strength (LSS) model of gradient elution in high-performance liquid chromatography (HPLC) has been demonstrated to provide parameters of lipophilicity and acidity of analytes. pKa and log kw values are determined in three gradient runs. The first two experiments use an aqueous buffered eluent with a wide-range organic modifier gradient at pH of buffer, providing suppression of ionization of the analyte. That experiment allows an estimate of contents of the organic modifier in the mobile phase (%B), producing requested retention coefficient, k, for the nonionized form of the analyte. The next experiment is carried out with the latter %B and a pH-gradient of the aqueous component of the eluent that is sufficient to overlap possible pKa value of the analyte. The initial pH of the buffer used to make the mobile phase is selected to insure that the analyte is in nonionized form. The resulting retention time allows an estimate of pKa in a solvent of the given %B.The log kw parameter obtained correlated well with the corresponding value obtained by the standard procedure of extrapolation of retention data determined in a series of isocratic measurements. The correlation between log kw and the reference parameter of lipophilicity, log P, was very good for a series of test analytes. The values of pKa were found to correlate with the literature pKa data determined in water for a set of aniline derivatives studied.

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Development and Validation of Retention Models in Supercritical Fluid Chromatography for Impregnation Process Design

Applied Sciences ◽

10.3390/app11157106 ◽

2021 ◽

Vol 11 (15) ◽

pp. 7106

Author(s):

Miaotian Sun ◽

Zeynep Ülker ◽

Zhixing Chen ◽

Sivaraman Deeptanshu ◽

Monika Johannsen ◽

...

Keyword(s):

Supercritical Fluid ◽

Supercritical Fluid Chromatography ◽

Stationary Phases ◽

Retention Factor ◽

Retention Mechanism ◽

Retention Data ◽

Retention Models ◽

Retention Factors ◽

Polar Solutes ◽

Porous Matrices

The retention factor is the key quantity for the thermodynamic analysis of the retention mechanism in chromatographic experiments. In this work, we measure retention factors for moderately polar solutes on four silica-based porous matrices as stationary phases by supercritical fluid chromatography. Elution of the solutes is only possible with binary mixtures of supercritical carbon dioxide (sc-CO2) and modifier (methanol) due to the low polarity of pure sc-CO2. The addition of modifiers makes the retention mechanism more complex and masks interactions between solute and stationary phase. In this work, we develop and validate several retention models that allow the obtaining of retention factors in modifier-free sc-CO2. Such models pave the way for quantifying adsorption interactions between polar solutes and non-swellable porous matrices in pure sc-CO2 based on retention data obtained in sc-CO2/modifier mixtures. The obtained information will thereby facilitate the understanding and design of impregnation processes, which are often performed in modifier-free conditions.

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