Explore the vast range of titles available.

A static method is employed to determine the solubilities of verapamil in supercritical carbon dioxide (SC-CO 2 ) at temperatures between 308 and 338 K and pressures between 12 and 30 MPa. The solubility of verapamil in SC-CO 2 expressed as mole fraction are in the range of 3.6 × 10 –6 to 7.14 × 10 –5 . Using four semi-empirical density-based models, the solubility data are correlated: Chrastil, Bartle, Kumar–Johnston (K–J), and Mendez-Santiago and Teja (MST), two equations of state (SRK and PC-SAFT EoS), expanded liquid models (modified Wilson's models), and regular solution model. The obtained results indicated that the regular solution and PC-SAFT models showed the most noteworthy exactness with AARD% of 1.68 and 7.45, respectively. The total heat, vaporization heat, and solvation heat of verapamil are calculated at 39.62, 60.03, and − 20.41 kJ/mol, respectively. Regarding the poor solubility of verapamil in SC-CO 2 , supercritical anti-solvent methods can be an appropriate choice to produce fine particles of this drug.

Oil from seeds of Diospyros lotus was extracted using a conventional method with two different solvents: hexane and petroleum ether. A central composite design with response surface methodology were used to optimize the process. A second-order polynomial equation was employed, and ANOVA was applied to evaluate the impact of various operating parameters including extraction temperature ( x 1 ; 44.9–70.1 °C), extraction time ( x 2 ; 5.0–10.0 h) and solvent to solid ratio ( x 3 ; 11.6–28.4 mL g −1 ), on oil yield. Experiments to validate the model showed decent conformity between predicted and actual values. Extraction conditions for optimal oil yield were 61 °C, 8.75 h extraction duration and 19.25 mL g −1 solvent to solid ratio. Under these conditions, the oil yield was predicted to be 5.1340%. Oil samples obtained were then analyzed using gas chromatography. The fatty acid composition revealed the major fatty acids to be oleic acid (C18:1) and linoleic acid (C18:2). The analysis of oil also demonstrated a decent ratio between omega-3 and omega-6 fatty acids. The structure of seeds was imaged using scanning electron microscopy. Oil quality was analyzed thermogravimetrically and by Fourier transform infrared spectroscopy. The assigned nutritional features of the D. lotus oil suggested that it can be used as an edible oil in pharmaceutical and food industry in the future.

In this research, the extraction with supercritical carbon dioxide (SC-CO2) and the subsequent impregnation of the extracted bioactive compounds from Zataria multiflora Boiss (Z. multiflora) into polylactic acid (PLA) films was investigated. The effects of temperature (318 and 338 K), pressure (15 and 25 MPa) and cosolvent presence (0 and 3 mol%) on the extraction yield were studied. The SC-CO2 assisted impregnation runs were carried out in a discontinuous mode at different pressure (15 and 25 MPa), temperature (318 and 328 K), and time (2 and 8 h) values, using 0.5 MPa min−1 as a constant value of depressurization rate. ANOVA results confirmed that pressure, temperature, and time influenced the extraction yield. Moreover, antioxidant activities of extracts of Z. multiflora were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. In addition, the antibacterial activities of the extracts were screened against standard strains of Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The results of this investigation indicated that extracts obtained from the aerial parts of Z. multiflora possessed antioxidant and antibacterial properties. The impregnated samples presented strong antibacterial activity against the selected microorganisms.

Supercritical gas antisolvent (GAS) process is an efficient method for nanoparticles production, in which accurate selection of operational condition is essential. Thermodynamic models can be applied for evaluation the phase equilibrium behavior and determination the required precipitation pressure of GAS process. In this research, thermodynamic behavior of (CO 2 —dimethyl sulfoxide (DMSO)) binary system and both of (CO 2 –DMSO-anthraquinone Violet 3RN (AV3RN)) and (CO 2 –DMSO-solvent Yellow 33 (SY33)) ternary systems in the GAS process were studied at different temperatures (308, 318, 328 and 338) K and pressures (1.0–14.0) MPa, using Peng–Robinson equation of state (PR-EoS). The minimum precipitation pressure of AV3RN and SY33 at 308, 318, 328 and 338 K were 7.80, 8.57, 9.78 and 11 MPa and 8, 8.63, 9.5 and 10.77 MPa, respectively. Also, the mole fraction of substances in liquid phase of ternary systems were determined by PR-EoS, at 328 K versus pressure. The accuracy of the obtained results were investigated using the experimental data reported in the literatures.

Evaluating the solubility of various drugs in supercritical CO 2 is a fundamental step in developing a supercritical process for formulating new pharmaceuticals. Atorvastatin, Lovastatin, and Simvastatin are statin drugs with limited solubility and low bioavailability. Their solubility in supercritical CO 2 has already been experimentally measured. This study provides a thorough theoretical analysis of this topic using novel advanced empirical models, fugacity coefficient-based and liquid thermodynamic models, and various machine learning techniques. Finally, the accuracy of the employed models is validated by comparing their outputs with the experimental data. For all the drugs studied, the empirical models proposed by Bian et al., Si-Moussa et al., Belghait et al., Pitchaiah et al., and Trishen Reddy et al. exhibit the highest accuracy, with AARD values below 10% and R adj values above 0.99, indicating the least deviation from the experimental data and the best fit. Moreover, both the PC-SAFT and Wilson thermodynamic models demonstrate satisfactory performance in correlating the experimental solubility data for all drugs, with a mean AARD of 6–8% and a R adj ranging from 0.97 to 0.995. Furthermore, the machine learning model based on an artificial neural network (ANN) showed high accuracy in estimating the solubility of the selected drugs in supercritical CO 2 .

Synthetic dye wastewater is a significant environmental concern, particularly due to its extensive usage in industries such as textiles, printing, and dyeing. Traditional methods for treating wastewater with synthetic dyes are often seen as costly and inefficient, primarily because of the dyes’ robust chemical nature. In light of these challenges, there has been a growing interest in recent years in the use of biodegradation. This method utilizes specific microorganisms capable of breaking down these stubborn pollutants, offering a more sustainable and effective solution for their removal. Given the limited detailed studies on the bacterial decolorization of oil-soluble (solvent-soluble) azo dyes, there is a significant need to address this issue. The ability of salt-tolerant bacteria named Halomonas strain A3 to decolorize an oil soluble azo dye, Toluidine Red was investigated. Decolorization conditions, including initial dye concentration, pH, NaCl percent (w/v), and incubation temperature, were optimized using the one-factor-at-a-time method with dye as the sole carbon and energy source. The ultraviolet-visible spectrophotometric method, high-performance liquid chromatography, and gas chromatography mass spectrometry analyses were used to investigate the decolorization mechanism at optimum condition, including 25 ppm dye concentration, 5% (w/v) NaCl, pH 6.5, and incubation temperature of 35 °C. Compared to the parent dye, the ultraviolet-visible scan of the supernatant suggested that the degradation mechanism was the main reason for color removal rather than inactive surface adsorption. HPLC analysis confirmed this conclusion. The final compounds produced from TR degradation were identified as benzene diazonium (m/z 105 ± 1) and 3-Phenyl-acrylic acid (m/z 149 ± 1). According to the results, Halomonas strain A3 is a practical alternative for degrading effluents containing oil-soluble azo dyes in salty conditions. A pathway for dye degradation was predicted based on the obtained intermediate and final products.

The solubility of an anti-hyperglycemic agent drug, (R)-4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro [1,2,4] triazolo[4,3-a] pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl) butan-2-amine (also known as Sitagliptin phosphate ) in supercritical carbon dioxide (scCO 2 ) was determined by ananalytical and dynamic technique at different temperatures (308, 318, 328 and 338 K) and pressure (12–30 MPa) values. The measured solubilities were in the range of 3.02 × 10 –5 to 5.17 × 10 –5 , 2.71 × 10 –5 to 5.83 × 10 –5 , 2.39 × 10 –5 to 6.51 × 10 –5 and 2.07 × 10 –5 to 6.98 × 10 −5 in mole fraction at (308, 318, 328 and 338) K, respectively. The solubility data were correlated with existing density models and with a new association model.

This study investigated the solubility of chlordiazepoxide in supercritical carbon dioxide (SCCO₂) at pressures ranging from 12 to 30 (MPa) and temperatures ranging from 308 to 338 (K). The measured solubilities ranged from 19.8 to 576 parts per million (ppm), or mole fractions of 0.0198 × 10⁻³ to 0.576 × 10⁻³. We used two equations of state (SRK and ECM-PR), enlarged liquid models, and semi-empirical analysis to assess the experimental data. Applying these models to the experimental solubility data of the chlordiazepoxide-SCCO₂ system revealed that Chrastil’s empirical models best aligned with the two sets of data. An important step in understanding the system’s behavior was applying the SRK and UNIQUAC models to the drug’s solubility data. Density-dependent empirical models, particularly the Chrastil correlation (AARD% = 5.30, R² = 0.996) and the UNIQUAC model (AARD% = 6.12), provided the highest predictive accuracy for chlordiazepoxide solubility in SCCO₂. In contrast, cubic EoS models (SRK and ECM-PR) exhibited significant deviations, with AARD% values approaching 20%, suggesting their limited reliability for this system. The UNIQUAC model indicated excellent accuracy, with AARD% of 6.12 and R 2 of 0.981 in correlating solubility data of this binary system.

In order to provide the facilities to design the supercritical fluid (SCF) processes for micro or nanosizing of solid solute compounds such as drugs, it is essential to obtain their solubility in green solvents like pressurized CO . This important role is the first stage for assessing each SCF technology. A statistical method was developed for the first time and employed to determine 5-fluorouracil (5-Fu) solubility. The measurements were performed at different pressures (120-270 bar) and temperatures (308-338 K) through UV-vis spectrophotometry, for the first time. The solubility was obtained between 0.0024 and 0.0176 g/L. The 5-Fu mole fraction at constant temperature, increases with an increase in pressure. Whereas, a crossover point has been seen. Three models with different approaches were applied to correlate and model the experimental data set: (i) seven density-based models, (ii) PR equations of state (vdW2 mixing rule), and (iii) machine learning-based models, namely non-linear regressions, Random Forest, Gradient Boosting, Decision Tree, and Kernel Ridge. All tested models successfully correlate and model the solubility data within an acceptable accuracy. Meanwhile, the empirical model suggested by Sodeifian model 2, is superior with the lowest AARD% (AARD = 4.12%). Finally, total, solvation, and vaporization enthalpies of the drug/Sc-CO binary system were determined using semi-empirical correlations, for the first time.

The supercritical fluid extraction of essential oil from rosemary leaves and its subsequent impregnation in linear low-density polyethylene (LLDPE) films were studied. The effects of temperature (318 and 338 K), pressure (15 and 25 MPa) and rosemary particle size (0.9 and 0.15 mm) on the extraction yield were investigated. Impregnation assays were developed at two different values of pressure (12 and 20 MPa), temperature (308 and 328 K), and impregnation time (1 and 5 h). The extraction yield of rosemary essential oil was increased by increasing pressure and decreasing particle size and temperature. ANOVA results showed that temperature, pressure, and time significantly impacted the essential oil impregnation yield in LLDPE films. The maximum impregnation yield (1.87 wt. %) was obtained at 12 MPa, 328 K, and 5 h. The antioxidant activity and the physical-mechanical properties of impregnated films were analyzed. The IC50 values for all the impregnated LLDPE samples were close to the IC50 value of the extract showing that the impregnated films have a significant antioxidant activity.