Thermodynamic Assessment of Triclocarban Dissolution Process in N-Methyl-2-pyrrolidone + Water Cosolvent Mixtures.

Solubility is one of the most important physicochemical properties due to its involvement in physiological (bioavailability), industrial (design) and environmental (biotoxicity) processes, and in this regard, cosolvency is one of the best strategies to increase the solubility of poorly soluble drugs in aqueous systems. Thus, the aim of this research is to thermodynamically evaluate the dissolution process of triclocarban (TCC) in cosolvent mixtures of {N-methyl-2-pyrrolidone (NMP) + water (W)} at seven temperatures (288.15, 293.15, 298.15, 303.15, 308.15, 313.15 and 318.15 K). Solubility is determined by UV/vis spectrophotometry using the flask-shaking method. The dissolution process of the TCC is endothermic and strongly dependent on the cosolvent composition, achieving the minimum solubility in pure water and the maximum solubility in NMP. The activity coefficient decreases from pure water to NMP, reaching values less than one, demonstrating the excellent positive cosolvent effect of NMP, which is corroborated by the negative values of the Gibbs energy of transfer. In general terms, the dissolution process is endothermic, and the increase in TCC solubility may be due to the affinity of TCC with NMP, in addition to the water de-structuring capacity of NMP generating a higher number of free water molecules.

Nanoformulations of curcumin and quercetin with silver nanoparticles for inactivation of bacteria.

Antibiotic resistance in pathogenic bacteria to various types of antibiotics has resulted in the necessity of new effective strategies to get around this problem. In recent investigations, metal or metal oxide nanoparticles specifically silver nanoparticles (AgNPs) have been employed successfully to hinder antibiotic-resistant Gram-negative and Gram-positive bacteria. However, AgNPs at high concentrations have cytotoxicity for eukaryotic cells which, application of other biocompatible materials particularly plant secondary metabolites of curcumin and quercetin to reduce cytotoxicity is a critical affair. These compounds may be used directly or indirectly to produce AgNPs. In this regard, modified NPs by curcumin and quercetin have shown an increased therapeutic effect and biocompatibility and biodegredibility properties. Therefore, here, recent advances and challenges about antibacterial and biocompatibility properties of nanoformulation of AgNPs with curcumin and quercetin are presented.

Thermodynamic Analysis of the Solubility of Isoniazid in (PEG 200 + Water) Cosolvent Mixtures from 278.15 K to 318.15 K.

The solubility of drugs in cosolvent systems of pharmaceutical interest is of great importance for understanding and optimizing a large number of processes. Here, we report the solubility of isoniazid in nine (PEG 200 + water) cosolvent mixtures at nine temperatures (278.15, 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, and 318.15 K) determined by UV-vis spectrophotometry. From the solubility data, the thermodynamic solution, mixing, and transfer functions were calculated in addition to performing the enthalpy-entropy compensation analysis. The solubility of isoniazid depends on the concentration of PEG 200 (positive cosolvent effect) and temperature (endothermic process) reaching its maximum solubility in pure PEG 200 at 318.15 K and the lowest solubility in pure water at 278.15 K. The solution process is favored by the solution entropy and according to the enthalpy-entropy compensation analysis it is driven by entropy in mixtures rich in water and by enthalpy in mixtures rich in PEG 200.

Solubility of Sulfamethazine in the Binary Mixture of Acetonitrile + Methanol from 278.15 to 318.15 K: Measurement, Dissolution Thermodynamics, Preferential Solvation, and Correlation.

Solubility of sulfamethazine (SMT) in acetonitrile (MeCN) + methanol (MeOH) cosolvents was determined at nine temperatures between 278.15 and 318.15 K. From the solubility data expressed in molar fraction, the thermodynamic functions of solution, transfer and mixing were calculated using the Gibbs and van 't Hoff equations; on the other hand, the solubility data were modeled according to the Wilson models and NRTL. The solubility of SMT is thermo-dependent and is influenced by the solubility parameter of the cosolvent mixtures. In this case, the maximum solubility was achieved in the cosolvent mixture w0.40 at 318.15 K and the minimum in pure MeOH at 278.15 K. According to the thermodynamic functions, the SMT solution process is endothermic in addition to being favored by the entropic factor, and as for the preferential solvation parameter, SMT tends to be preferentially solvated by MeOH in all cosolvent systems; however, δx3,1<0.01, so the results are not conclusive. Finally, according to mean relative deviations (MRD%), the two models could be very useful tools for calculating the solubility of SMT in cosolvent mixtures and temperatures different from those reported in this research.

Solubility of codeine phosphate in carbitol + 2-propanol mixture at different temperatures.

The solubility profile of codeine phosphate in the carbitol and 2-propanol mixtures at 293.2-313.2 K are determined and correlated with some developed cosolvency models. Moreover, the density values of codeine phosphate saturated solutions are also determined and fitted with the Jouyban-Acree model. The model accuracy is investigated by calculating the mean relative deviations (MRDs%). The thermodynamic parameters of codeine phosphate dissolution in the non-aqueous mixtures of carbitol and 2-propanol are also computed by using van't Hoff and Gibbs equations.

Effect of Tetrabutylammonium Bromide-Based Deep Eutectic Solvents on the Aqueous Solubility of Indomethacin at Various Temperatures: Measurement, Modeling, and Prediction with Three-Dimensional Hansen Solubility Parameters.

Deep eutectic solvents (DESs) have recently been getting a great deal of attention in many fields of science and technology. The objective of this study was to peruse the solubility of indomethacin (IMC) as sparingly soluble drug in some tetrabutylammonium bromide (TBAB)-based DESs (TBAB/ethylene glycol and TBAB/glycerol). The shake flask method has been employed in this study at temperature ranges T = (298.15-313.15) K and atmospheric pressure (pP = 86.6 kPa). The results showed that the solubility of IMC in TBAB/ethylene glycol system was obtained approximately 17,000-fold more than its solubility in water. The solubility data were accurately correlated by the famous local composition activity coefficient models including e-NRTL and UNIQUAC. It was also our aim to evaluate Hansen solubility parameters in IMC solubility prediction. These parameters can help to predict the solvent performance during the manufacturing processes and will be useful in guessing solvent behavior in many other fields of effort. The experimental and the Hansen solubility parameters results are very well matched. In addition, the apparent thermodynamic properties of dissolution and mixing were studied in these solutions based on Van't Hoff and Gibbs equations.

The Effect of Extraction by Pressing at Different Temperatures on Sesame Oil Quality Characteristics.

Sesame oil has been widely used in the daily diet due to its high nutritional value. Sesame oil is extracted at industrial scales and also in small scale by cold pressing at different temperatures. In this research, sesame oil was extracted by pressing at four temperatures, namely, 30 (control sample), 60, 90 and 120 °C, to evaluate its effects on the quality of extracted oils. Oil extraction yields were increased from 38 to 51% by increasing the pressing temperature. The highest amount of peroxide and acid values were related to the oil extracted at 120 °C. Tocopherols and total phenol content were reduced by the increasing the pressing temperature, and the highest amounts of these bioactive components were related to the control sample. The results of the fatty acids profile showed that the composition of oils extracted at different temperatures did not differ significantly (p > 0.05). The results of the present study give a clear picture about the effects of different pressing temperatures on the sesame oil quality and extraction yield, and can be useful in the extraction unit optimization.

Relationship between the solution thermodynamic properties of naproxen in organic solvents and its release profiles from PLGA microspheres.

Naproxen (NPX)-loaded poly-(D,L-lactic-co-glycolic acid) (PLGA) microparticles were prepared by the emulsion-solvent evaporation method. The different organic solvents used significantly affects the properties of the microparticles obtained. These microparticles exhibited a controlled release profile that extends up to 15 days depending on the organic solvent used. The formulations did not exhibit zero- or first-order release kinetics and no agreement with Higuchi or Korsmeyer-Peppas models was obtained. In all cases, the dissolution profiles were fitted to the model proposed by Gallagher and Corrigan for PLGA systems. It was found that this model fully describes the dissolution processes. An interesting relationship between the NPX solubility in the organic solvents studied and some parameters obtained for the dissolution model of the microparticles prepared with the same solvents is thus obtained. Accordingly, it can be proposed that the drug solubility in organic solvents is relevant to estimate the physical characteristics of microparticles other than its dissolution profiles.

Measurement and correlation of solubility data for deferiprone in propylene glycol and 2-propanol at different temperatures.

This investigation dealt with the thermodynamic properties, saturated solubility values, and solvation behavior of deferiprone as an oral iron chelator agent in non-aqueous mixtures of propylene glycol and 2-propanol using experimental measurements and mathematical correlations. The solubility of deferiprone demonstrated a positive correlation with both temperature and propylene glycol mass fraction. Four mathematical models were employed to correlate the solid-liquid equilibrium data, and the low mean relative deviation values of less than 3.6% illustrate the good agreement of computed data with the experimental data. The apparent thermodynamic behavior of deferiprone dissolution was also investigated according to van't Hoff and Gibbs equation.

Preferential Solvation Study of Rosuvastatin in the {PEG400 (1) + Water (2)} Cosolvent Mixture and GastroPlus Software-Based In Vivo Predictions.

Rosuvastatin (RST) is a poorly water-soluble drug responsible for limited in vivo dissolution and subsequently low oral systemic absorption (poor bioavailability). The mole fraction solubility values of RST in various ratios of binary mixtures "{PEG400 (1) + water (2)}" at 298.15 K were employed to investigate the preferential solvation (PS) of RST (3) by the binary components. Moreover, the GastroPlus program predicted the drug dissolution/absorption rates, plasma drug concentration, and compartmental regional drug absorbed from a conventional tablet as compared to the RST-loaded (PEG400 + water) mixture (at x 1 = 0.5) in healthy subjects (considering the fast condition). Fedors' method was adopted to estimate the values of molar volume (314.8 cm3·mol-1) and Hildebrand solubility parameter (28.08 MPa1/2) of RST. The results of inverse Kirkwood-Buff integrals showed the PS of RST by PEG400 as observed in all studied ratios of the binary mixture. The highest PS value (δx 1,3 = 1.65 × 10-2) for RST by PEG400 was attained at x 1 = 0.5. Finally, the GastroPlus program predicted the maximum dissolution rate [20 mg within 15 min as compared to pure RST (1.5 mg within 15 min)]. Moreover, the program predicted increased in vivo oral absorption (1.2 µg/mL) and enhanced regional absorption (95.3%) of RST from upper segments of the gastrointestinal tract for the RST-loaded PEG400 + water mixture in humans as compared to conventional tablets (87.5% as total regional absorption and 0.88 µg/mL as in vivo absorption). Hence, the present binary system ferrying RST can be a promising strategy to control systemic dyslipidemia after oral or subcutaneous administration.

Study of Mesalazine Solubility in Ternary Mixtures of Ethanol, Propylene Glycol, and Water at Various Temperatures.

Mesalazine is a low-permeable and low-soluble drug, which makes it a class IV drug in the Biopharmaceutics Classification System. Hence, its solubilization can be helpful for various stages of formulation development. The purpose of this study was to investigate the solubilization manner and thermodynamics of mesalazine in ternary solvent combinations of {ethanol (1) + propylene glycol (2) + water (3)} using the shake-flask technique at (298.2-313.2) K. In the following, the mathematical representation of the acquired solubility data using some popular models was evaluated. The accuracies of the applied models were described by percentages of mean relative deviation (MRD%). Based on obtained results (MRD% < 10.0), it can be concluded that the trained models can adequately predict the solubility of mesalazine in the investigated ternary solvent combinations. The findings also revealed that the solution composition and temperatures greatly influence the solubility of mesalazine. In addition, the thermodynamic characteristics of the mesalazine dissolution process indicate that the mesalazine dissolution process is endothermic and entropy-driven. The generating data in the current work also expands the available solubility database for mesalazine in the solvent mixtures.

A review on anticancer, antibacterial and photo catalytic activity of various nanoparticles synthesized by probiotics.

Probiotics are beneficial bacteria that have a significant effect on host health and they are widely used in preventing and treating diseases. Nowadays probiotics are present in food, drug and several commercial complement products. In recent years the use of probiotics in the nanotechnology area, especially in nanoparticle synthesis, has significantly been increased. In this review, after some introduction about probiotic and their advantages, all the nanoparticles produced by probiotics are reviewed and discussed. Furthermore, biosynthetic mechanisms of nanoparticles and its applications in cancer therapy, antibacterial and photo catalytic activities, are also discussed.

Effect of N-Methyl-pyrrolidone (NMP) on the Equilibrium Solubility of Meloxicam in Aqueous Media: Correlation, Dissolution Thermodynamics, and Preferential Solvation.

Meloxicam is an analgesic and anti-inflammatory drug widely prescribed in current therapeutics that exhibits very low solubility in water. Thus, this physicochemical property has been studied in N-methyl-pyrrolidone (NMP)-aqueous mixtures at several temperatures to expand the solubility database about pharmaceutical compounds in aqueous-mixed solvents. The flask-shake method and UV-vis spectrophotometry were used for meloxicam solubility determination as a function of temperature and mixture composition. Several cosolvency models, including the Jouyban-Acree model, were challenged for equilibrium solubility correlation and/or prediction. The van't Hoff and Gibbs equations were employed here to calculate the apparent standard thermodynamic quantities for the dissolution and mixing processes of this drug in these aqueous mixtures. Inverse Kirkwood-Buff integrals were employed to calculate the preferential solvation parameters of meloxicam by NMP in all mixtures. Meloxicam equilibrium solubility increased with increasing temperature, and maximal solubilities were observed in neat NMP at all temperatures. The mole fraction solubility of meloxicam increased from 1.137 × 10-6 in neat water to 3.639 × 10-3 in neat NMP at 298.15 K. The Jouyban-Acree model correlated the meloxicam solubility in these mixtures very well. Dissolution processes were endothermic and entropy-driven in all cases, except in neat water, where nonenthalpy- nor entropy-driven was observed. Apparent Gibbs energies of dissolution varied from 34.35 kJ·mol-1 in pure water to 7.99 kJ·mol-1 in pure NMP at a mean harmonic temperature of 303.0 K. A nonlinear enthalpy-entropy relationship was observed in the plot of dissolution enthalpy vs dissolution Gibbs energy. Meloxicam is preferentially hydrated in water-rich mixtures but preferentially solvated by NMP in the composition interval of 0.16 < x 1 < 1.00.

Preferential Solvation Study of the Synthesized Aldose Reductase Inhibitor (SE415) in the {PEG 400 (1) + Water (2)} Cosolvent Mixture and GastroPlus-Based Prediction.

(Z)-N-Benzyl-2-{2,4-dioxo-5-(4-prop-2-yl-1-yloxyl)benzylidene)thiazolin-3-yl)}acetamide (SE415) is a novel aldose reductase inhibitor used in the management of diabetes mellitus (DM) and associated complications. Herein, the drug was solubilized (mole fraction solubility) in a "PEG 400 (polyethylene glycol 400) + water" mixture of various ratios at 298.15 K. We reported the preferential solvation of SE415 by PEG 400 using Kirkwood-Buff integrals, the thermodynamic functional parameter, in vitro dissolution, and GastroPlus-based predictions for in vivo performance. The result of Hansen solubility parameter analysis suggested PEG 400 as a suitable solvent for SE415 solubilization at 298.0 K, followed by prediction of several physicochemical properties. In the preferential solvation study, the molar volume, Hildebrand solubility parameters, and the molecular radius of SE415 were estimated as 258.4 cm3·mol-1, 27.62 MPa1/2, and 0.468 nm, respectively, using Fedors' method. The inverse Kirkwood-Buff integrals indicated that the preferential solvation of SE415 by PEG 400 occurred in all studied ratios of the (PEG 400 + water) mixtures. The maximum value (δx 1,3 = 1.21 × 10-2) of the preferential solvation of SE415 by PEG 400 was achieved at x 1 = 0.15. Then, using GastroPlus software, the maximum dissolution, improved in vivo oral absorption, and high regional compartmental absorption (total 99.0%) of SE415 in humans were predicted. Finally, the solubility data were correlated/predicted using various cosolvency models with satisfactory results. Thus, the binary cosolvent system can be a promising approach for enhanced oral absorption in controlling DM and associated complications in humans.

Eudragit S100 microparticles containing Spodoptera frugiperda nucleopolyehedrovirus: physicochemical characterization, photostability and in vitro virus release.

The aim of this study was to encapsulate the occlusion bodies (OBs) of Spodoptera frugiperda nucleopolyhedrovirus (SfNPV) in Eudragit S100 microparticles (MPs), considering this technique as a possible alternative to protect them from deleterious environmental conditions. The MPs were prepared by oil-in-oil emulsion (O/O) solvent evaporation method. Experimental conditions were established according to a previous multi-level experimental design involving the core/polymer ratio as independent variable. The effects of these parameters on particle size and process yield were investigated observing that polymer concentration had a significant effect on particle size. After adequate conditions for MPs formation were determined, virus was encapsulated. The virus microparticles presented a particle size between 50-300 microm and concentration was 2.62 x 10(9) OBs g(-1). Microencapsulation efficiency was 53.43% and virus release adjusted to Higuchi model suggesting diffusion as the release mechanism. Evaluated microencapsulation process protected viral particles of UV-inactivation, suggesting its potential for a biopesticide development.

Study of naproxen in some aqueous solutions of choline-based deep eutectic solvents: Solubility measurements, volumetric and compressibility properties.

Naproxen (NAP) is a widely used drug for the treatment of pain and inflammatory conditions. However, there is not the physicochemical information about this drug such as solubility, volumetric and compressibility properties in the presence of deep eutectic solvents (DES) as a new class of green solvents to overcome the low solubility of drugs. In this work, the solubility of NAP is studied in the solutions containing some choline chloride (ChCl) based DES at temperature ranges (298.15-313.15) K. The results indicate that the solubility increases with increasing the concentration of DES and temperature and DES containing malonic acid is the proper co-solvent. The experimental solubility values were correlated by the e-NRTL, Wilson and UNIQUAC models. In addition, the complex interactions between the components in the systems should be elucidated, therefore, the thermodynamic properties including volumetric and compressibility properties have been investigated using density and speed of sound measurements at T = 298.15 K. According to calculated thermodynamic parameters, strong interactions between NAP and DESs are observed which is in agreement with obtained solubility data.

Thermodynamic study of the transfer of acetanilide and phenacetin from water to different organic solvents.

The molar (K(C)(o/w)) and rational (K(X)(o/w)) partition coefficients in the octanol/buffer, i-propyl myristate/buffer, chloroform/buffer, and cyclohexane/buffer systems were determined for acetanilide and phenacetin at 25.0, 30.0, 35.0, and 40.0 degrees C. In all cases except for cyclohexane, the K(C)(o/w) and K(X)(o/w) values were greater than unity. This demonstrates that these two drugs have predominantly lipophilic behavior. Gibbs and van't Hoff thermodynamic analyses have revealed that the transfer of these drugs from water to organic solvents is spontaneous and that it is mainly driven enthalpically for i-propyl myristate and chloroform, and entropy-driven for octanol and cyclohexane.

Solubility of Naproxen in Polyethylene Glycol 200 + Water Mixtures at Various Temperatures.

The solubility of naproxen in binary mixtures of polyethylene glycol 200 (PEG 200) + water at the temperature range from 298.0 K to 318.0 K were reported. The combinations of Jouyban-Acree model + van't Hoff and Jouyban-Acree model + partial solubility parameters were used to predict the solubility of naproxen in PEG 200 + water mixtures at different temperatures. Combination of Jouyban-Acree model with van't Hoff equation can be used to predict solubility in PEG 200 + water with only four solubility data in mono-solvents. The obtained solubility calculation errors vary from ~ 17 % up to 35 % depend on the number of required input data. Non-linear enthalpy-entropy compensation was found for naproxen in the investigated solvent system and the Jouyban-Acree model provides reasonably accurate mathematical descriptions of the thermodynamic data of naproxen in the investigated binary solvent systems.