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The solubility of loxoprofen as a nonsteroidal anti-inflammatory drug (NSAID) is measured at various temperatures (308, 318, 328, and 338 K) and pressures (12, 16, 20, 24, 28, 32, 36, and 40 MPa) i...

In the current investigation, the solubility of fenoprofen as a nonsteroidal anti-inflammatory drug in supercritical CO2 (SC-CO2) is measured by employing a motorized PVT (pressure–volume–temperatu...

Carbonated brine (CB) injection, known as one of the effective enhanced oil recovery processes, is highly dependent on the reservoir conditions (i.e. temperature and pressure) as well as the type of dissolved salt in aqueous solution. This study is aimed to investigate the influential parameters on the swelling of crude oil as the most important mechanism during CB injection. The swelling of crude oil in the presence of different CB solutions consisted of different salts such as KCl, NaCl, CaCl2 and MgCl2 with constant concentration of 15,000 ppm is studied using a high-pressure, high-temperature visual cell which measures the volume of drop using image processing software based on Young-Laplace method. Also, the Δ Bond number of crude oil is examined to more reliably find out the mechanisms. According to the results, it can be concluded that the solubility of CO2 in aqueous phase is not the only parameter affecting the swelling behavior, and that the crude oil and ion type as well as temperature have remarkable effect on the mobility of CO2 molecules and their partitioning from aqueous phase toward oil phase.

Unfortunately, malaria still remains a major problem in tropical areas, and it takes thousands of lives each year and causes millions of infected cases. Besides, on December 2019, a new virus known as coronavirus appeared, that its rapid prevalence caused the World Health Organization (WHO) to consider it a pandemic. As a potential drug for controlling or treating these two undesired diseases at the cellular level, chloroquine and its derivatives are being investigated, although they possess side effects, which must be reduced for effective and safe treatments. With respect to the importance of this medicine, the current research aimed to calculate the solubility of chloroquine in supercritical carbon dioxide, and evaluated effect of pressure and temperature on the solubility. The pressure varied between 120 and 400 bar, and temperatures between 308 and 338 K were set for the measurements. The experimental results revealed that the solubility of chloroquine lies between 1.64 × 10−5 to 8.92 × 10−4 (mole fraction) with different functionality to temperature and pressure. Although the solubility was indicated to be strong function of pressure and temperature, the effect of temperature was more profound and complicated. A crossover pressure point was found in the solubility measurements, which indicated similar behaviour to an inflection point. For the pressures higher than the crossover point, the temperature indicated direct effect on the solubility of chloroquine. On the other hand, for pressures less than the crossover point, temperature enhancement led to a reduction in the solubility of chloroquine. Moreover, the obtained solubility results were correlated via semi-empirical density-based thermodynamic correlations. Five correlations were studied including: Kumar & Johnston, Mendez-Santiago-Teja, Chrastil, Bartle et al., and Garlapati & Madras. The best performance was obtained for Mendez-Santiago-Teja's correlation in terms of average absolute relative deviation percent (12.0%), while the other examined models showed almost the same performance for prediction of chloroquine solubility., Highlights • Measuring solubility of chloroquine in supercritical CO2 • Thermodynamic modeling of chloroquine solubility at different conditions • Solubility of chloroquine lies between 1.64 × 10−5 to 8.92 × 10−4 (mole fraction).

Design and development of efficient processes for continuous manufacturing of solid dosage oral formulations is of crucial importance for pharmaceutical industry in order to implement the Quality-by-Design paradigm. Supercritical solvent-based manufacturing can be utilized in pharmaceutical processing owing to its inherent operational advantages. However, in order to evaluate the possibility of supercritical processing for a particular medicine, solubility measurement needs to be carried out prior to process design. The current work reports a systematic solubility analysis on decitabine as an anti-cancer medicine. The solvent is supercritical carbon dioxide at different conditions (temperatures and pressures), while gravimetric technique is used to obtain the solubility data for decitabine. The results indicated that the solubility of decitabine varies between 2.84 × 10–05 and 1.07 × 10–03 mol fraction depending on the temperature and pressure. In the experiments, temperature and pressure varied between 308–338 K and 12–40 MPa, respectively. The solubility of decitabine was plotted against temperature and pressure, and it turned out that the solubility had direct relation with the pressure due to the effect of pressure on solvating power of solvent. The effect of temperature on solubility was shown to be dependent on the cross-over pressure. Below the cross-over pressure, there is a reverse relation between temperature and solubility, while a direct relation was observed above the cross-over pressure (16 MPa). Theoretical study was carried out to correlate the solubility data using several thermodynamic-based models. The fitting and model calibration indicated that the examined models were of linear nature and capable to predict the measured decitabine solubilities with the highest average absolute relative deviation percent (AARD %) of 8.9%.

One of the effective medications for Glioblastoma Multiforme is Temozolomide (TMZ) which is taken as a treatment for some brain cancers. With respect to the importance of this drug in cancer therapy, the solubility of this medicine was analyzed under various ranges of pressure and temperature in supercritical carbon dioxide (SC-CO2) to evaluate the possibility of drug micronization for reducing its undesired side effects. The measurements were conducted using gravimetric method and revealed that the solubility of the drug is between 4.30 × 10−4 to 5.28 × 10−3 based on mole fraction. The results demonstrated the strong dependency of the TMZ solubility to pressure and temperature, while the effect of pressure is more profound at higher temperatures. Besides, the calculated solubility data was correlated employing five popular semi-empirical density-based correlations including Bartle et al., Chrastil, Kumar and Johnston, Mendez-Santiago-Teja, and Garlapati & Madras models. The obtained outcomes illustrated that among the tested models, KJ led to the best correlative ability with average absolute relative deviation percent (AARD %) of 8.39%, while Garlapati and Madras led to the worst modeling results with AARD % of 15.20%.

Particle size and morphology are among the most important parameters which must be precisely controlled in pharmaceutical industries to enhance the effectiveness of the solid dosage oral formulations. One of the most interesting methods for controlling these two quality attributes is supercritical fluid based technologies by which the drug solubility in supercritical (SC) solvent, commonly carbon dioxide, dictates whether the used method is applicable for suitable particle production or not. In this work, solubility of an anti-cancer drug namely tamoxifen in supercritical CO2 was measured under different conditions. The measurements were carried out between 120 and 400 bar pressure, and 308–338 K temperature. The measurements revealed the solubility of about 1.88 × 10−5 to 9.89 × 10−4 (mole fraction basis) for tamoxifen with strong functionality to pressure and complicated functionality to temperature. In details, pressure showed to have a direct effect on solubility, while the effect of temperature depends on existence of cross-over pressure that is about 200 bar for the case of tamoxifen. It was revealed that for the pressures greater than the cross-over point, increasing temperature led to enhancement of the tamoxifen solubility due to sublimation pressure dominanacy, while for pressures lower than cross-over point, density reduction (solvating power reduction) is the dominant mechanism as the temperature enhances. Besides the experimental measurements, the possibility of correlating and extrapolating the measured solubility of tamoxifen as a function of temperature and pressure was investigated using five well-known semi-empirical density-based models including Kumar-Johnston (K-J), Garlapati-Madras, Chrastil, Mendez-Santiago and Teja (MST), and Bartle et al., among which KJ model showed the lowest average absolute relative deviation percent of about 8.26%.

Elimination of carbon dioxide from gas mixtures is a common commercial step in natural gas refineries. Nowadays, room-temperature ionic liquids, which are a relatively novel type of compounds have gained attention in recent years and have potential to be considered as a substitution for conventional volatile organic solvents in reaction and separation processes. No flammability, high thermal stability, a wide liquid range, and electric conductivity are some properties of ILs, which make them interesting more and more. Information about the solubility and the rate of solubility is a crucial factor for consideration of ILs for potential industrial processes. Because of some difficulties associated with experimental measurements and expenses spent on ILs, developing predictive methods for prognostication of the phase behavior of such types of systems are more favorable. Thermodynamic models are relatively complex and require complicated mathematical operations. Due to such difficulties there is a need to develop general models capable to predict phase behavior of systems such as CO2 with various kinds of ILs. In this study, four different methods based on artificial intelligence are proposed to predict CO2 solubility in different ionic liquids. The results showed that the predicted values are in great agreement with the experimental data and the maximum absolute error deviation for the best predictor is no more than 3.5%. A comparison between developed models and previously published ones reveals the superiority of the proposed models in this study.

In the current study, the solubility of busulfan which is a chemotherapy drug for treating chronic myelogenous leukemia (CML) is measured in supercritical carbon dioxide (SC-CO2) at pressures between 120 and 400 bar, and temperatures between 308 and 338 K. It was indicated that the solubility of this drug via a static solubility measurement technique coupled with a gravimetric approach was between 3.27 × 10−5 to 8.65 × 10−4 (mole fraction). The measured solubility data reveled the direct effect of pressure on the solubility data, while the temperature has a dual effect of both increasing and decreasing effect considering the shifting point known as cross-over pressure which was measured to be around 160 bar for busulfan. Moreover, a theoretical approach was implemented to predict the solubility data using thermodynamic models. Indeed, five widely used semi-empirical density based correlations namely Kumar-Johnston (KJ), Bartle et al., Mendez-Santiago and Teja (MST), Garlapati and Madras and Chrastil models were used to model solubility data using only pressure, temperature and density of mixture as input parameters. The modeling as well as curve fitting results demonstrated that among the examined models, KJ model introduced more accurate correlative capability with AARD of about 7.57%.

The tunable nature of the solubility of various compounds, including molecules of pharmaceutical and biological interest, in supercritical fluids (SCFs) makes SCF extraction technology attractive for many separation and purification processes. Among the different influencing parameters, the most important one in the supercritical based processes is the knowledge of solubility of model solute. But, experimental measurement of the solubility of all pharmaceuticals in wide ranges of temperature and pressure is not only cost effective but also impossible in some cases. Regarding this fact, during the past decades, several approaches are proposed to model the solubility of the compounds in the supercritical fluids especially carbon dioxide. In this way, in the current investigation, two different approaches including five semi-empirical density based correlations (Mendez-Santiago and Teja (MST), Bartle et al., Chrastil, Kumar and Johnston (KJ) and Hezave et al.) and Peng-Robinson equation of state are used to find if it is possible to correlate the solubility of cetirizine with acceptable deviation as a function of temperature and pressure. The results reveal that among the examined approaches Hezave and Lashkarbolooki model leads to better overall correlative capability with average absolute relative deviation of 5.04% although Peng-Robinson EoS leads to lower AARD % of 3.85 % in 338 K isotherm.

During the past decades, producing micro- and nano-particles of drugs is gaining attention since it is possible to modify the solubility of insoluble drugs in the gastronical fluids significantly. Respect to this fact, in the current investigation, rapid e...

In recent years, using supercritical carbon dioxide for different chemical processes in particular particle micronization has been surprisingly increased. Knowing the substance solubility in supercritical solvent is a critical parameter during the particle size reduction processes. In this direction, solubility of cephalexin was measured in the supercritical carbon dioxide by changing the temperature and pressure between 308.15 K to 338.15 K and 16 Mpa to 40 MPa, respectively. The measured solubility of cephalexin in supercritical carbon dioxide was in the range of 1.13×10-5 to 4.89 ×10-3 based on the mole fraction at the different operational condition. Besides the experimentally measurement of cephalexin solubility, modeling of the results using four commonly used correlations namely Mendez-Santiago and Teja (MST), Bartle, Kumar and Johnston and Chrastil models were performed. The results revealed that the Chrastil model is the most accurate used semi-empirical correlation in the present study with the lowest average absolute relative deviation percent of (AARD %) of 9.43 %.

Solubility of chlorpheniramine maleate in supercritical carbon dioxide at different temperatures (308–338 K) and pressures (160–400 bar) is measured using static method coupled with gravimetric method. The measured solubility data demonstrated that the solubility of chlorpheniramine maleate was changed between 1.54 × 10−5 and 4.26 × 10−4 based on the mole fraction as the temperature and pressure are changed. The general trend of measured solubility data shows a direct effect of pressure and temperature on the solubility of chlorpheniramine maleate. Finally, the obtained solubilities correlated using four semi-empirical density-based correlations including Mendez Santiago–Teja (MST), Kumar and Johnston (KJ), Bartle et al., and Chrastil models. Although the results of modeling showed that the KJ model leads to the average absolute relative deviation percent (AARD %) of 8.1% which is the lowest AARD %, deviation of other utilized correlations are rather the same.

Solubility of solute in supercritical fluids at different pressures and temperatures is one of the most important parameters necessary for design of any supercritical fluid-based processes. Among different supercritical fluids, carbon dioxide is one of the most widely used solvents due to its useful and green characteristics. In this work, with the assist of supercritical carbon dioxide as the solvent, solubility of cyproheptadine in different temperatures (308–338 K) and pressures (160–400 bar) are measured using static method. The obtained results demonstrated that solubility of cyproheptadine ranged between 3.35 × 10−5 and 3.09 × 10−3 based on mole fraction. A closer examination of measured solubility data show that not only solubility of cyproheptadine increases by increasing pressure but also experiences a cross over pressure about 200 bar. At last, the measured solubility data are correlated using four widely used density based correlations namely Mendez Santiago–Teja (MST), Kumar and Johnston (KJ), Bartle et al., and Chrastil models. The obtained results demonstrated that the best correlative capability was observed for KJ model leads to the average absolute relative deviation percent (AARD %) of 6.3%.

This study was aimed to measure the solubility of carvedilol in the temperature and pressure ranges of 308⿿338 K and 160 bar to 400 bar, respectively. In this direction, a homemade high pressure visual equilibrium cell was used to measure the solubility of carvedilol using a static method coupled with gravimetric technique. The results revealed that the carvedilol solubility was ranged between 1.12 y 10⿿5 and 5.01 y 10⿿3 based on the mole fraction (mole of carvedilol/mole of carvedilol + mole of CO2) in this study as the temperature and pressure was changed. Finally, the results were correlated using four density-based semi-empirical correlations including Chrastil, Mendez⿿Santiago⿿Teja (MST), Bartle et al., and Kumar and Johnston (K-J) models. Results revealed that although the K-J model leads to the lowest average absolute relative deviation percent (AARD %) of 6.27%, but it could not be considered as the most accurate correlation since all the used four correlations introduces AARD % of about 6⿿10% which may be in the same range as the experimental error.

Since the knowledge of pharmaceutical solubilities in the supercritical carbon dioxide is one of the first essential necessities for designing the supercritical carbon dioxide-based processes, solubility of piroxicam a non-steroidal anti-inflammatory drug was experimentally measured. In this regard, a static method coupled with gravimetric method was used to measure the solubility of piroxicam in the supercritical carbon dioxide in temperature and pressure range of 308.15–338.15 K and 16–40 MPa, respectively. The obtained solubility data were in the range of 1.17 × 10 −5 and 5.12 × 10 −4 based on the mole fraction (mole piroxicam/(mole piroxicam + mole CO 2 )) then modeled using four different density based correlations namely Bartle et al., Mendez-Santiago-Teja, Chrastil and Kumar and Johnston models. The results of error analysis revealed that the used correlations were potential to correlate the solubility of piroxicam with minimum and maximum average absolute relative deviation percents (AARD%) of 14.4% and 15.2%, respectively.

The purpose of this study was to measure the solubility of gabapentin in supercritical carbon dioxide at different pressures and temperatures of 16–40 MPa and 308–338 K, respectively. The measured solubility data revealed that solubility of gabapentin was 8.97 × 10 −5 –7.36 × 10 −3 based on the mole fraction in supercritical carbon dioxide at the aforementioned operational conditions. At last, the obtained results were correlated using four density based semi-empirical correlations namely Bartle et al., Mendez-Santiago and Teja (MST), Chrastil and Kumar and Johnston (K–J). The results revealed that according to the obtained average absolute relative deviations (AARD) for the used density based correlations of MST (AARD % = 9.88%), Chrastil (AARD % = 9.47%), K–J (AARD % = 11.5%) and Bartle et al. (AARD % = 9.29%), none of the correlations can be considered as the most accurate one. In other words, all the examined semi-empirical correlations are in the same level of accuracy.

Phenylephrine is used as a decongestant sold as an oral medicine, as a nasal spray, or as eye drops. Phenylephrine is now the most common over-the-counter decongestant in the United States. In this regard, measuring the solubility of phenylephrine hydrochloride seems applicable in supercritical carbon dioxide-based processes dealing with this drug. The obtained solubility data obtained by a static method coupled with gravimetric method were in the range of 1.01 × 10 −4 to 2.89 × 10 −3 based on the mole fraction at the different temperature and pressure ranges of 308.15–338.15 K and 160–400 bar, respectively. In addition, the solubility data were used to obtain the adjusting parameters of semi-empirical correlations namely Kumar and Johnston, Bartle et al., Chrastil and Mendez-Santiago-Teja using a simple data regression.

In the pharmaceutical industry where the supercritical fluid-based technologies are utilized it is very important and vital to know the accurate value of the equilibrium solubility of solids required for the engineers to determine the size of the equipments. According to this requirement, the purpose of this study was measuring the solubility of fluoxetine hydrochloride with IUPAC name of 3-phenyl-3-[4-(trifluoromethyl)phenoxy]propan-1-amine hydrochloride using a static method coupled with gravimetric method. The measured solubility data at the temperature and pressure range of 308.15–338.15 K and 16–40 MPa was ranged between 2.65 × 10 −5 and 8.12 × 10 −4 based on the mole fraction. The results revealed that the solubility was increased when the pressure was increased while the effect of the temperature was more complex. Finally, the measured solubility data were correlated using three different correlations namely Bartle et al., Mendez-Santiago–Teja and Kumar and Johnston. The results of modeling revealed that the Bartle et al. model leads to the lowest average absolute relative deviation (AARD %) of 9.48.

During the past 20 years, an increase through measuring, correlating, and calculating solid solubilities especially pharmaceuticals in supercritical fluids for processes such as purification, extraction, and size reduction processes have been observed. In this direction, the solubility of amoxicillin with the International Union of Pure and Applied Chemistry (IUPAC) name of (2S,5R,6R)-6-{[(2R)-2-amino-2-(4-hydroxyphenyl)-acetyl]amino}-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0] heptane-2-carboxylic acid in the pressure and temperature ranges of 16 MPa to 40 MPa and 308.15 K to 338.15 K, respectively, has been measured. For this purpose, a simple gravimetric-based method was utilized to obtain the amoxicillin solubility in supercritical carbon dioxide. During the measurements it was found that the amoxicillin solubility was in the range of 1.08·10–5 and 7.23·10–3 based on the mole fraction. Besides, due to a vast number of efforts have been performed on the solubility correlation by several researchers, ...

Solubility measurements of solids in supercritical fluids have been increasingly performed during the past three decades, and semi-empirical models are utilizing as one of the best methods to fit this type of data. For the proper design of supercritical fluid drug process, it is essential to have a sufficient knowledge of the drug solubilities in supercritical fluids particularly carbon dioxide because of its green characterization. In this regards, the solubility of sulindac with IUPAC name of {(1Z)-5-fluoro-2-methyl-1-[4-(methylsulfinyl)benzylidene]-1H-indene-3-yl}acetic acid were examined in the wide ranges of temperature and pressure of 308.15–338.15 K and 160–400 bar, respectively, in supercritical carbon dioxide. The obtained results show the sulindac solubility was in the range of 3.65 × 10−5 to 8.69 × 10−3 mole fraction and additionally was correlated with four density based semi-empirical correlations namely, Mendez-Santiago–Teja, Bartle, Chrastile and Kumar and Johnston methods.

The equilibrium solubility of the diclofenac acid in supercritical carbon dioxide was determined with a static method. The measurements were performed at pressures ranging from (120 to 400) bar and temperatures from (308.15 to 338.15) K. The results show that diclofenac acid solubility was increased by increasing pressure. The experimental solubility data were well correlated with enhanced density-based models including the Chrastil model, Mendez-Santiago and Teja model, Kumar and Johnston model, and the Bartle and co-workers model with an average absolute relative deviation (AARD) of 8.7 %, 6.6 %, 7.2 %, and 9.7 %, respectively. In addition, the solubility data satisfied the self-consistency test, proposed by Mendez-Santiago and Teja.

The main goal of this study was to measure the solubility of mefenamic acid in supercritical carbon dioxide (SC-CO2) at pressures and temperatures range of 16–40 MPa and 308.15, 318.15, 328.15 and 338.15 K, respectively. The obtained results revealed that the mole fractions were varied in the range of 8.31 × 10−5–5.98 × 10−3 under the different conditions. The obtained results were correlated with four empirical correlations including Chrastil, Mendez-Santiago–Teja (MST), Bartle and Kumar and Johnston (K–J) models. The optimized parameters of these correlations were obtained by the graphical regression. The calculated results show a good consistency between the measured and calculated solubilities for Chrastil, MST, Bartle and Kumar and Johnston models with average absolute relative deviation percent (AARD%) of 5.84%, 3.93%, 4.79%, and 5.20%, respectively. In addition, experimental results were modeled with two equations of state including the Esmaeilzadeh–Roshanfekr (ER) and Peng–Robinson (PR) EoSs which their binary interaction parameters, kij and lij, were optimized by the differential evolution (DE) method. DE is a very simple population based stochastic function minimizer which is very powerful at the same time. The estimated solubilities show maximum AARD% of 21.25% and 30.56% and minimum AARD% of 3.54% and 6.81% were found for the ER and PR-EOS's, respectively.

A simple static technique was used to obtain the solubility of cetirizine in supercritical carbon dioxide. The solubility measurements were performed at temperatures and pressures ranging from 308.15 to 338.15 K and 160 to 400 bar, respectively; resulting in mole fractions in the 1.05 × 10 −5 to 4.92 × 10 −3 range. The Chrastil, Bartle, Kumar & Johnston and the Mendez-Santiago and Teja (MST) models were used to correlate the experimental data. The calculated solubilities showed good agreement with the experimental data in the temperature and pressure ranges studied.

In pharmaceutical industry, many drugs exhibit poor solubility in biological fluid. Solubility of drugs affects on the rate of dissolution and bioavailability in biological fluids. The bioavailability of drugs can be enhanced by decreasing the drug particle size. In this study, sulindac was micronized via rapid expansion of supercritical solution (RESS) where CO2 was used as a solvent. The experiments were conducted to investigate the effect of the extraction pressure and temperature (140–230 bar and 40–60 °C), collection distance (1–10 cm), effective nozzle diameter (450–1700 μm) and nozzle length (2–15 mm) on the size and morphology of the sulindac particles. The size and morphology of the precipitated particles were monitored by scanning electron microscopy (SEM). The particle size of intact sulindac particles was about 33.03 μm, while the average particle size of the micronized sulindac particles was between 0.76 and 8.02 μm based on different experimental conditions. Additionally, the different morphology of the micronized particles was observed like needle, rectangular, quasi spherical and irregular form while the morphology of the intact particles of sulindac was rectangular and irregular.

During the past 20 years, supercritical fluid (SCF) based technologies have been gaining an increasing attention through the academic and industrial communities due to its advantages. One of the most important parameter for any supercritical-based technologies is the knowledge of the solute solubility at different pressures and temperatures. But, due to several concerns e.g. time and expense, measuring the solubility of all compounds in wide ranges of temperature and pressure is not possible. Respect to this, a new empirical correlation with four fitting parameters has been proposed to correlate the solubility of pharmaceuticals in different temperatures and pressures. The obtained results compared with four widely used density based correlations including Mendez-Santiago and Teja (MST), Bartle et al., Chrastil, Kumar and Johnston (KJ) revealed rather good capability of the proposed simple correlation for predicting the solubility of solutes in supercritical carbon dioxide (SC- CO 2). At last, the obtained results compared with the results of three Equations of State (EoS's) with three different mixing rules.