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HPLC-fluorescence detection for assay of tramadol binary mixtures with ibuprofen or chlorzoxazone in tablets and plasma : analytical Eco-Scale and GAPI tools for green assessment

Hamdy Mohamed M.A., Abdel Moneim Mona M.

Acta Chromatographica

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2022

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Vol. 34, no. 2

185--196

EN

Tramadol, a strong pain killer known for its addictive problems is either co-administrated or co-formulated with other analgesics or muscle relaxants. The power of fluorescence detection in HPLC is tested to resolve such mixtures in plasma matrix to reach the required sensitivity with simple sample treatment using just protein precipitation. The aim of this work was to develop an eco-friendly and sensitive HPLC method with fluorimetric detection for analysis of Tramadol in its two binary mixtures with Ibuprofen (mixture 1) and Chlorzoxazone (mixture 2) in two combined dosage forms and spiked plasma. Separation was done using a C18 column with mobile phase of acetonitrile and water (pH 3.5) in gradient elution and 1 mL/min flow rate. Detection was carried out with λ excitation/λ emission of 220 and 307 nm, respectively. The method was applied to detect the two binary mixtures in real plasma samples after invivo application to rats, to assure that the drugs’ metabolites do not affect the sensitivity or selectivity of the assay. Evaluation of greenness of the proposed method was done using semi-quantitative Eco‐Scale and new Green Analytical Procedure Index which showed that this method can be a greener alternative with higher sensitivity for analysis of both mixtures. The method (15 min-assay) was linear over concentrations of 0.1–10 μg/mL and 0.1–33 μg/mL in plasma. In addition, the proposed method was validated per ICH as well as FDA bioanalytical methods’ validation guidelines.

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Limitations of FEM modelling of chloride diffusion when considering different parameters of binary and ternary concrete mixtures

Lehner Petr, Hornakova Marie, Konecny Petr

Budownictwo o Zoptymalizowanym Potencjale Energetycznym

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2020

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Vol. 9 Nr 2

61--69

EN

The numerical modelling of chloride diffusion in concrete structures requires an appropriate description of input parameters. The main inputs for the model are the diffusion coefficient of concrete and derived aging factor. The model itself can be susceptible to the values of these parameters because of the size of the finite elements and size of the time step. Due to the potential use in probabilistic calculations, which requires millions of simulations, it is desirable to create a highly optimized model. It is important to pay attention to the accuracy of the calculation, but also to its calculation time. The presented results show the possible limits of the finite element model of the diffusion in a concrete structure. This is demonstrated on the reference ordinary Portland cement mixture and 32 various binary and ternary concrete mixtures, which show a significant effect of different diffusion coefficients and aging factors on the overall convergence. This study provides guidance on which extreme material parameters, out of the potential range, may adversely affect model results.

3

Electrostatic separation of binary mixtures of some biodegradable polymers and poly(vinyl chloride) or poly(ethylene terephthalate)

Żenkiewicz M., Żuk T., Pietraszek J., Rytlewski P., Moraczewski K., Stepczyńska M.

Polimery

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2016

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T. 61, nr 11-12

835--843

EN

There are presented results of investigation of electrostatic separation of binary mixtures containing a biodegradable polymer {polylactide (PLA), polycaprolactone (PCL), or poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3,4HB)]} and a commonly used polymer [poly(vinyl chloride) (PVC) or poly(ethylene terephthalate) (PET)]. It was found that the binary mixtures of these polymers could be efficiently separated. The electrostatic separation process of the P(3,4HB)/PET mixture appeared to be most successful. It is indicated that the share of a biodegradable component in the mixture essentially influences the separation effects. Therefore, suitable choice of necessary conditions is needed to perform the separation process, which includes appropriate separator settings, depending on fractions of individual components in the mixture being separated.

PL

W artykule przedstawiono wyniki badań procesu separacji elektrostatycznej mieszanin dwuskładnikowych zawierających polimery biodegradowalne {polilaktyd (PLA), polikaprolakton (PCL) lub poli(3-hydroksymaślan-co-4-hydroksymaślan) [P(3,4HB)]} i polimery powszechnego użytku [poli(chlorek winylu) (PVC) lub poli(tereftalan etylenu) (PET)]. Stwierdzono, że mieszaniny tych polimerów mogą być skutecznie rozdzielane w tym procesie. Najbardziej efektywna okazała się separacja mieszaniny P(3,4HB)/PET. Z badań wynika również, że najistotniejszym czynnikiem wpływającym na skuteczność tej separacji jest udział masowy składnika biodegradowalnego w danej mieszaninie. Z tych względów wymagany jest odpowiedni dobór warunków prowadzenia separacji elektrostatycznej, w tym nastaw separatora w zależności od udziału poszczególnych składników mieszaniny rozdzielanej.

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Study on thermodynamic properties of binary mixtures of diethyl carbonate with benzonitrile, benzaldehyde at different temperatures

Sudhamsa B., Babu M. S., Narendra K.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 19, iss. 1

1--7

EN

The speed of sound and density in binary liquid mixture of diethyl carbonate + benzonitrile, + benzaldehyde have been determined at temperatures 298.15, 308.15 and 318.15 K over the whole composition range. The data have been utilized to estimate the excess adiabatic compressibility (βE), excess intermolecular free length (Lf E), excess speed of sound (uE) at the above temperatures. The excess values have been found to be useful in estimating the strength of the interactions in the liquid mixtures.

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Acoustical studies on binary liquid mixtures of some 1,3,4-oxadiazole derivatives with acetone at 303.15 K

Alamelumangai G., Santhi N.

International Letters of Chemistry, Physics and Astronomy

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2014

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Vol. 5

124--133

EN

The wide spread use of 1,3,4-oxadiazoles as a scaffold in medicinal chemistry establishes this moiety as an important bioactive class of heterocycles. In the present study ultrasonic velocity (u), density (ρ) and viscosity (η) have been measured at frequency 2 MHz in the binary mixtures of 1,3,4-oxadiazole derivatives in acetone at 303.15 K using ultrasonic interferometer technique. The measured value of ultrasonic velocity, density and viscosity have been used to estimate the acoustical parameters namely adiabatic compressibility (βad), relaxation time (τ), acoustic impedance (Zi), free length (Lf), free volume (Vf) and internal pressure (πi), with a view to investigate the nature and strength of molecular interactions. The obtained result support the occurrence of molecular association through hydrogen bonding in the binary liquid mixtures.

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Analiza modeli kinetycznych stosowanych w opisie biofiltracji dwuskładnikowych mieszanin lotnych związków organicznych

Karcz J., Szyszka D.

Inżynieria i Aparatura Chemiczna

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2006

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Nr 5s

55-58

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Effent of Temperature on Speed of Utrasound Ind Adiabatic Comressibility of Binary Moxtures of 1,2-Ethanediol+1-Pentanol

Zorębski E.

Molecular and Quantum Acoustics

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2004

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Vol. 25

291-296

EN

The excess values of the molar adiabatic compressibility as well as adiabatic compressibility coefficeint were estimated for binary mixtures of 1,2-ethanediol+1-pentanol at the temperatures (293.15, 303.15, 308.15 and 313.15) K. Alsko deviations of the ultrasonic speed from the chosen additivity rules were determinated. Together with the previous result for T = 298.15K (E. Zorębski, Mol.Quant Acoust.,24 261-270 (2003)), the effect of temperature on speed of ultrasound and adiabatic compressibility is studied. It appears that both excesses decrease with increasing temprature whereas deviations of ultrasonic speed have opposite temperature dependencies.

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Speeds of Ultrasound and Adiabatic Compressibilities of Binary Mixtures of 1,2-Ethanediol+1-Pentanol At 298.15k

Zorębski E.

Molecular and Quantum Acoustics

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2003

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Vol. 24

261-270

EN

The excess values of the molar adiabatic compressibility as well as adiabatic compressibility coefficient were estimated for binariy mixtires of 1,2-ethanediol+1-pentanol at 298.15K. Also deviations of the ultrasonic speed from the chosen additivity rules were determined. Both the excess quantities as well as the speed of ultrasound are expressed by the Redlich-Kister polynomials and discussed in terms of molecular interactions

9

Excess Volumes and Adiabatic Cmpressibilities of Binary Mixtures of Cyclohexanol + Glycerol at 298.15h

Zorębski E.

Molecular and Quantum Acoustics

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2002

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Vol. 23

463-472

EN

The excess values of the molar volume and molar adiabatic compressibility as well as adiabatic compressibility coefficient were estimated for binariey mixtures of cyclohexanol + glycerol at 298.15K. Also deviations of the ultrasonic speed from the chosen additivity rules were determined. Both the excess quantities as well as the speed of ultrasound deviations are expressed by the Redlich-Kister polynomials and aisscused in term of molecular interactions.

10

Hydrogen bonded complexes of coumarin 153

Królicki R., Jarzęba W., Soroushian B., Lampre I., Mostafavi M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 4

435-449

EN

Detailed studies of the hydrogen-bonded complexes of coumarin 153 (C153) have been carried out. It has been shown that nonlinear shifts of the steady-state absorption and fluorescence spectra taken in toluene-methanol solvent mixtures are caused by the formation of hydrogen bonded complexes between C153 and methanol, while preferential solvation plays a minor role only. IR measurements confirmed the ability of C153 to form hydrogen-bonded complexes with methanol and phenol. The stoichiometry of the formed complexes and relevant equilibrium constants have been estimated. Femtosecond solvation dynamics measurements of C153 in the toluene-methanol mixture (xMeOH = 0.2) showed that the average solvation time is higher than that in the pure solvents indicating slower relaxation of methanol in the mixture. The slow component of solvation dynamics (ok 20ps) can be attributed to translational diffusion of methanol to the first solvation shell of C153 and to the relatively slow reorientational motion of methanol involved in formation of hydrogen bond with the excited C153.

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Kink conditions for isobars in binary v-x-phase diagrams induced by the second low

Bauer W., Muschik W.

Archives of Thermodynamics

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1998

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Vol. 19, no 3/4

59-83

EN

Conditions describing the behaviour of the kink of the isobars at the dew line in v-x-phase diagrams of binary mixtures are proved using the second low. These conditions are tested using a generalized Bender equation of state with mixture rules of Tsai and Shuy. The complete set of formulas of such a type of equation is worked out for being useful in programming or modification of other equations of state or mixture rules.