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An air sanitizer was evaluated using an aerobiology protocol, compliant with the U.S. Environmental Protection Agency's Air Sanitizer Guidelines, for virucidal activity against bacteriophages Phi6 and MS2 (used as surrogates for enveloped and non-enveloped human pathogenic viruses). The phages were suspended in a medium containing a tripartite soil load simulating body fluids and aerosolized using a six-jet Collison nebulizer in an enclosed 25 m³ aerobiology chamber at 22 ± 2°C and 50 ± 10% relative humidity. The air sanitizer was sprayed into the chamber for 30 s. Viable phages in the air were captured directly, in real time, on host bacterial lawns using a slit-to-agar sampler. Reductions in viable phage concentration ≥3.0 log10 (99.9%) were observed after a mean exposure of 3.6 min for Phi6, suggesting efficacy against enveloped viruses (e.g., SARS-CoV-2, influenza, and RSV), and ~10.6 min for MS2, suggesting virucidal efficacy for non-enveloped viruses (e.g., noroviruses and rhinoviruses). This targeted air sanitization approach represents an important non-pharmaceutical public health intervention with virucidal efficacy against airborne viral pathogens. [ABSTRACT FROM AUTHOR]

Air sanitization is an important non-pharmaceutical intervention for mitigating the risk of indoor pathogen spreading. A dipropylene glycol-containing air sanitizer was tested against aerosolized Staphylococcus aureus and Klebsiella pneumoniae. The bacteria, suspended in a soil load, were aerosolized using a six-jet Collison nebulizer with pressurized air. The 25-m3 (~900 ft3) aerobiology chamber was maintained at 22 ± 2 °C and 50 ± 5% relative humidity per the U.S. Environmental Protection Agency's 2012 Guidelines on air sanitizers. An initial 2-min air sample was collected from the chamber using a slit-to-agar sampler containing 150-mm Petri plates, with Trypticase soy agar (TSA) containing neutralizers to quench the microbicidal activity of the air sanitizer, to determine the initial bacterial challenge in the air. The air sanitizer was sprayed into the chamber from pressurized cans. Additional air samples were collected from the chamber over 10 min to detect surviving bacteria. The TSA plates were then incubated aerobically at 36 ± 1 °C for 90 ± 4 h and scored for bacterial colony-forming units. A 30-s spray of the air sanitizer reduced infectious S. aureus and K. pneumoniae titers by 3.0 log10 (99.9%) in 3.2 ± 0.3 min and 1.2 ± 0.0 min, respectively. Based on these findings, the EPA granted registration of the air sanitizer as the first product of its kind for indoor air sanitization. [ABSTRACT FROM AUTHOR]

Ethanol is one of the most utilized additives in gasoline, and its obtaining and separation from regenerable resources is of great interest. Despite the enormous energy consumption, extractive and azeotropic distillation is still preferred for ethanol anhydrization. This work studies the utilization of dipropylene glycol (DPG) as an extractive agent. The vapor–liquid equilibrium (VLE) data for the ethanol + DPG binary system was experimentally determined and the VLE data obtained were regressed using Non-Random Two Liquid (NRTL) and Universal Quasi Chemical (UNIQUAC) thermodynamic models in PRO/II 2020 simulation software. The binary interaction parameters obtained from regression were used to simulate the water + ethanol separation by extractive distillation with DPG. There were realized a series of several simulations, using different solvent/feed ratios in the extractive distillation column, starting from two basic variants: variant A, where no heat recovery is considered, and variant B, where the heat of the hot streams in the process flow diagram (PFD) is recovered in three heat exchangers. The specific energy consumption (SEC) expressed as MJ/kg of anhydrous ethanol were calculated for each variant. It was found that the most economical is variant B which for the SEC is 7.53 MJ/kg of anhydrous ethanol. The SEC calculated for the best variant in this study is lower than the SEC calculated by other researchers for similar processes. [ABSTRACT FROM AUTHOR]

Air sanitization is an important non-pharmaceutical intervention for mitigating the risk of indoor pathogen spreading. A dipropylene glycol-containing air sanitizer was tested against aerosolized Staphylococcus aureus and Klebsiella pneumoniae. The bacteria, suspended in a soil load, were aerosolized using a six-jet Collison nebulizer with pressurized air. The 25-m3 (~900 ft3) aerobiology chamber was maintained at 22 ± 2 °C and 50 ± 5% relative humidity per the U.S. Environmental Protection Agency’s 2012 Guidelines on air sanitizers. An initial 2-min air sample was collected from the chamber using a slit-to-agar sampler containing 150-mm Petri plates, with Trypticase soy agar (TSA) containing neutralizers to quench the microbicidal activity of the air sanitizer, to determine the initial bacterial challenge in the air. The air sanitizer was sprayed into the chamber from pressurized cans. Additional air samples were collected from the chamber over 10 min to detect surviving bacteria. The TSA plates were then incubated aerobically at 36 ± 1 °C for 90 ± 4 h and scored for bacterial colony-forming units. A 30-s spray of the air sanitizer reduced infectious S. aureus and K. pneumoniae titers by 3.0 log10 (99.9%) in 3.2 ± 0.3 min and 1.2 ± 0.0 min, respectively. Based on these findings, the EPA granted registration of the air sanitizer as the first product of its kind for indoor air sanitization.

Despite many efforts to improve the transdermal permeability of drugs, most of them are blocked by the skin barrier. Niacinamide (NAC) is a Biopharmaceutics Classification System class I drug with high aqueous solubility and intestinal permeability. Due to the high solubility and intestinal permeability of NAC, the development of new formulations is insufficient as transdermal, injection etc. Thus, this study aimed to develop the novel NAC formulation with improved skin permeability and secured stability. The NAC formulation approach is to first select a solvent that improves skin permeability, and then select a second penetration enhancer to determine the final formulation. All formulations were evaluated for skin permeability using an artificial membrane (Strat-M®). The optimal formulation (non-ionic formulations (NF1) consisted of NAC/Tween®80 = 1:1 wt ratio in dipropylene glycol [DPG]) showed the highest permeability in all formulations in PBS buffer (pH 7.4). The thermal properties of NF1 were altered. Moreover, NF1 maintained a stable drug content, appearance, and pH value for 12 months. In conclusion, DPG had an excellent effect in increasing the NAC permeation, and Tween®80 played a boosting role. Through this study, an innovative NAC formulation was developed, and good results are expected for human transdermal research.

Despite many efforts to improve the transdermal permeability of drugs, most of them are blocked by the skin barrier. Niacinamide (NAC) is a Biopharmaceutics Classification System class I drug with high aqueous solubility and intestinal permeability. Due to the high solubility and intestinal permeability of NAC, the development of new formulations is insufficient as transdermal, injection etc. Thus, this study aimed to develop the novel NAC formulation with improved skin permeability and secured stability. The NAC formulation approach is to first select a solvent that improves skin permeability, and then select a second penetration enhancer to determine the final formulation. All formulations were evaluated for skin permeability using an artificial membrane (Strat-M®). The optimal formulation (non-ionic formulations (NF1) consisted of NAC/Tween®80 = 1:1 wt ratio in dipropylene glycol [DPG]) showed the highest permeability in all formulations in PBS buffer (pH 7.4). The thermal properties of NF1 were altered. Moreover, NF1 maintained a stable drug content, appearance, and pH value for 12 months. In conclusion, DPG had an excellent effect in increasing the NAC permeation, and Tween®80 played a boosting role. Through this study, an innovative NAC formulation was developed, and good results are expected for human transdermal research. [ABSTRACT FROM AUTHOR]

Case report, contact dermatitis, CAS 106-62-7, CAS 108-61-2, CAS 110-98-5, CAS 25265-71-8, dipropylene glycol, propylene glycol DPG may contain 0.24% to 1.0% PG.1 Both molecules are glycols (compound with two hydroxyl groups attached to carbon atoms) and diols (compound with two hydroxyl groups). Keywords: CAS 106-62-7; CAS 108-61-2; CAS 110-98-5; CAS 25265-71-8; case report; contact dermatitis; dipropylene glycol; propylene glycol EN CAS 106-62-7 CAS 108-61-2 CAS 110-98-5 CAS 25265-71-8 case report contact dermatitis dipropylene glycol propylene glycol 112 114 3 06/14/22 20220701 NES 220701 CASE REPORT A 66-year-old female presented with a 5-month history of intermittent axillary/arm/chest/abdomen/thigh dermatitis. [Extracted from the article]

We control the aggregation of short-side-chain (SSC) perfluorinated sulfonic acid (PFSA) ionomers for catalyst-layer (CL) inks by using a dispersion solvent of dipropylene glycol (DPG) and water. By increasing the fraction of PFSA backbone preferable DPG content in a dispersion solvent, the size of SSC-PFSA aggregates decreases exponentially from microscale to nanoscale, affecting the catalyst-ionomer agglomerates' size and distribution in the CL inks. The surface morphology and porosity properties of the resulting CL are investigated, and the fuel cell performances are studied at two different humidity conditions (50 and 100% RH). Compared to the previous study with long-side-chain (LSC) PFSA ionomers, the SSC-PFSA ionomers show the optimized performance at higher DPG content, where the solvating power is intermediate for SSC-PFSA ionomers having shorter hydrophilic side chain than LSC-PFSA ionomers. • The size of SSC-PFSA aggregations was tuned in binary solvents of DPG and water. • The size of ionomers and Pt/C-ionomers was investigated by DLS. • The morphology of CLs is presented by DPG content in the catalyst inks. • Total oxygen transport resistance of the CLs with the DPG contents was investigated. [ABSTRACT FROM AUTHOR]

• Tadalafil transdermal formulation with HDTMA-Br in dipropylene glycol (DPG) was successfully prepared. • All formulations were evaluated for in vitro transdermal permeability through artificial membrane (Strat-M®). • TDF-TD F1 increased TDF in vitro transdermal permeability by 1169.8- and 2.4-fold compared to those of B1 (DW) and B4 (DPG) formulations, respectively. • TDF-TD F1 is maintained the stability for 12 months. Tadalafil (TDF) has low water solubility, high intestinal permeability and belongs to the Biopharmaceutics Classification System (BCS) Class II. Due to high intestinal permeability, only oral administration (tablets) and oral thin film formulations have been developed. Therefore, it is necessary to develop various formulations, such as external formulations and transdermal absorption formulations requested by patients. The purpose of this study is to improve the solubility and skin permeability of TDF, and to develop a novel transdermal formulation with secured stability over time. The research strategy is to determine solvents that will improve TDF solubility and to screen substances that will enhance TDF permeability. Skin penetration tests were simulated by using a Strat-M® membrane in Franz diffusion cell systems. The optimal formulation (F1, consisting of TDF/HDTMA-Br at a ratio of 1:10 [weight/weight] in DPG) observed the highest permeability compared to all formulations in PBS (pH 7.4). Changes in thermal property of F1 formulation was observed and maintained its stability over 12 months including drug content (μg/mL), appearance, pH, and permeation (μg/cm2). In conclusion, DPG played a supported role in improving both TDF solubilization and permeability, whereas HDTMA-Br played a key role in enhancing permeability. It is thought that these results will be supplemented in the future to conduct research and experiments on humans. [Display omitted] [ABSTRACT FROM AUTHOR]

The kinetics of the hydration of propylene oxide was studied using a pressurized batch reactor for both uncatalyzed and heterogeneously catalyzed reactions. Lewatit MonoPlus M500/HCO3 - was used as heterogeneous catalyst, which showed better performance than Dowex Marathon A/HCO3 -. The effects of the parameters, namely internal and external diffusion resistances, temperature, catalyst loading and mole ratios of reactants, on the reaction rate were studied. The uncatalyzed and heterogeneously catalyzed reactions were proven to follow a series-parallel irreversible homogeneous mechanism. The temperature dependencies of the rate constants appearing in the rate expressions were determined.

Hypothesis The behavior/properties of micellar solutions are governed by Coulombic interactions that are influenced by the polarity of the surfactant head groups, hydrophobic tails, and solvent molecules. The addition of co-solvent should have a direct impact on solvent polarity and the size of the micelles are expected to decrease accordingly. Experiments In this study, a mixed surfactant system is studied composed of a common anionic surfactant, sodium laureth sulfate-1, modified by a zwitterionic surfactant, cocamidopropyl betaine in deuterated water. In this system, worm-like micelles (WLMs) are formed. The influence of a co-solvent, dipropylene glycol (DPG) in the present of high salt content, is investigated. DPG primarily modifies the dielectric constant of the solvent. Findings It was found that the addition of DPG slightly decreased the micelle radius, but dramatically reduced the persistence length as well as the contour length of the micelles. The relative dependence of contour length on salt concentration is not significantly changed. Thus, it is shown that the self-assembled structure can be tuned by adjusting solvent polarity without affecting the relative tunability of the WLM/ellipsoidal structure through counter ion concentration. [ABSTRACT FROM AUTHOR]

The density ( ρ ) and viscosity ( η ) data were measured on the binary system of dipropylene glycol (DPG) + 1,2-ethanediamine (EDA) with the different mole fractions at (293.15, 298.15, 303.15, 308.15, 313.15, and 318.15) K under atmospheric pressure. On the basis of the experimental ρ and η data, the excess molar volumes ( V m E ) and dynamic viscosity deviations (Δ ν ) were calculated. Meanwhile, the Redlich-Kister type function was employed to calculate the coefficients and evaluate the standard deviation between the experimental and calculated data by using V m E and Δ ν values. After that, the intermolecular interactions between EDA and DPG was discussed according to FTIR and UV–vis spectral results. [ABSTRACT FROM AUTHOR]

Solvent properties, solvation power and selectivity, are calculated for dipropylene glycol (DPG). Additionally, the performances realized by DPG in extraction columns were evaluated by simulating in PRO/II software the extraction of aromatic hydrocarbon from a fraction of Catalytic Reforming naphtha based on the binary interaction parameters obtained from liquid–liquid and vapor–liquid equilibrium experimental data for the binary mixtures of DPG with representative aromatic and non-aromatic hydrocarbons with six up to eight carbon atoms, as determined in previous works. The simulation of the extraction columns was achieved for different operating conditions: solvent mass ratios from 1:1 up to 4:1 and different numbers of theoretical trays in simple columns, solvent mass ratios from 1:1 up to 4:1 and different reflux ratios in columns operated with reflux of extract, and in columns operated with reflux of raffinate. The results show that DPG has a good solvation power, and its utilization in extraction ensures a pure raffinate is obtained. [ABSTRACT FROM AUTHOR]

In this present work, new experimental data for density and vapour pressure of the mixed-solvent desiccant systems containing {40 wt% glycol (propylene or dipropylene or tripropylene) + (4 or 9 or 16 wt%) magnesium chloride salt + water} were reported for temperatures up to 343.15 K at normal atmospheric condition. The density and vapour pressure data obtained are presented as a function of temperature and composition. An empirical equation was used to correlate the temperature and compositional dependence of the density values. A model based on the mean spherical approximation for aqueous electrolyte solutions incorporating the pseudo-solvent approach was used to represent the vapour pressure as a function of temperature and composition. Satisfactory results were obtained for both density and vapour pressure calculations. [ABSTRACT FROM AUTHOR]

Vapor–liquid equilibrium (VLE) data are reported for five binary systems involving propylene glycols. VLE data have been measured in the temperature range of 350.15–510.15 K and pressure up to 34.374 kPa for the binary systems: 1,2-propanediol (monopropylene glycol, MPG) + 2-[2-(2-hydroxypropoxy) propoxy]propan-1-ol (tripropylene glycol, TPG), MPG + 2-(2-[2-(2 hydroxypropoxy) propoxy]propoxy) propan-1-ol (tetrapropylene glycol, TePG), 1-(2-hydroxypropoxy) propan-2-ol (dipropylene glycol, DPG) + TPG, DPG + TePG and TPG + TePG. These experimental data are obtained using an equilibrium apparatus build in our laboratory. For the binary system MPG + DPG there are VLE data available in literature. The experimental data obtained were correlated using the NRTL model. These VLE data are essential for the process design in order to separate propylene glycols mixtures by distillation. [ABSTRACT FROM AUTHOR]

Abstract: Vapor–liquid equilibrium data was determined by using a static method for the binary mixtures of dipropylene glycol (4-oxa-2,6-heptanediol) with benzene, toluene, ethylbenzene, o-xylene, m-xylene, and p-xylene at temperatures within 293.15K–481.15K. The p–T–x experimental data obtained was regressed with NRTL and UNIQUAC thermodynamic models in order to obtain the binary interaction parameters of the models, specific to each mixture. Furthermore, the T–x–y diagrams were determined based on these parameters and then compared with the diagrams calculated using the UNIFAC predictive model. We observed differences between the T–x curves calculated with the two models mentioned above and the UNIFAC predictive model. [Copyright &y& Elsevier]

Abstract: In this present work, a thermophysical property characterization of aqueous ternary system containing n-tris-[hydroxymethyl]methyl-3-aminopropanesulfonic acid (TAPS) and glycol was done. Thermophysical properties, including refractive index, density, and electrolytic conductivity, measurements were considered. The glycols considered are propylene glycol (PG), dipropylene glycol (DPG), and tripropylene glycol (TPG). The measurements were done over a temperature range of 298.15K to 343.15K and at normal atmospheric pressure. Different concentrations (4% to 16% by weight TAPS or 56% to 44% water, in a fixed amount of glycol – 40%) were used. The effects of temperature and compositions on the measured properties were discussed and then correlated based on the equation proposed for aqueous salt–glycol systems. Calculation results show that the applied model was satisfactory in representing the measured properties in the aqueous ternary systems containing TAPS and considered glycols. [Copyright &y& Elsevier]

The toxicological profiles of monopropylene glycol (MPG), dipropylene glycol (DPG), tripropylene glycol (TPG) and polypropylene glycols (PPG; including tetra-rich oligomers) are collectively reviewed, and assessed considering regulatory toxicology endpoints. The review confirms a rich data set for these compounds, covering all of the major toxicological endpoints of interest. The metabolism of these compounds share common pathways, and a consistent profile of toxicity is observed. The common metabolism provides scientific justification for adopting a read-across approach to describing expected hazard potential from data gaps that may exist for specific oligomers. None of the glycols reviewed presented evidence of carcinogenic, mutagenic or reproductive/developmental toxicity potential to humans. The pathologies reported in some animal studies either occurred at doses that exceeded experimental guidelines, or involved mechanisms that are likely irrelevant to human physiology and therefore are not pertinent to the exposures experienced by consumers or workers. At very high chronic doses, MPG causes a transient, slight decrease in hemoglobin in dogs and at somewhat lower doses causes Heinz bodies to form in cats in the absence of any clinical signs of anemia. Some evidence for rare, idiosyncratic skin reactions exists for MPG. However, the larger data set indicates that these compounds have low sensitization potential in animal studies, and therefore are unlikely to represent human allergens. The existing safety evaluations of the FDA, USEPA, NTP and ATSDR for these compounds are consistent and point to the conclusion that the propylene glycols present a very low risk to human health. [ABSTRACT FROM AUTHOR]

Abstract: The dermal penetration of undiluted monopropylene glycol (MPG) and dipropylene glycol (DPG) has been measured in vitro using human abdominal skin under conditions of infinite dose application, and the results compared with predictions from the SKINPERM QSAR model (). The measured steady-state penetration rates (Jss ) for MPG and DPG were 97.6 and 39.3μg/cm2/h, respectively, and the permeability coefficients (Kp ) were 9.48×10−5 cm/h for MPG and 3.85×10−5 cm/h for DPG. In comparison, the SKINPERM model slightly over-predicted Jss and Kp for MPG and DPG by between 2.6- and 5.1-fold, respectively. The model predictions of 254μg/cm2/h and 24.6×10−5 cm/h for MPG, and 202μg/cm2/h and 19.8×10−5 cm/h for DPG were in fairly good agreement with the measured values. Further, the model predicted a Jss of 101μg/cm2/h and a Kp of 9.9×10−5 cm/h for the homologue tripropylene glycol. Assuming that the measured Jss was the same under conditions of finite dose application (taken to be 10μL/cm2) and was maintained over a 24-h period (both conservative assumptions), the relative dermal absorption of the applied dose was estimated to be 23% (0.96%/h) for MPG and 9% (0.39%/h) for DPG. However, the extrapolation for MPG may be further overestimated due to possible residence in the stratum corneum under infinite conditions of exposure that would not be applicable to a finite loading dose. [Copyright &y& Elsevier]

A method that allows direct identification and quantitative determination of dipropylene glycol (DPG) using 13C NMR spectroscopy was developed. The quantitative procedure was checked and validated with commercially available DPG, controlled with two DPG-added essential oils, and then applied to commercial 'Extraits de parfum' (perfume extracts). [ABSTRACT FROM AUTHOR]

Abstract: Binary mutual diffusion coefficient data for aqueous solutions of propylene and dipropylene glycols were measured using the Taylor dispersion technique for each aqueous binary system at different concentrations (x 1 =0.2–0.80) and temperatures (303.2–323.2K). The measured data were fit to different empirical and semi-theoretical models and compared with the values predicted from such models. The measured mutual diffusion coefficient data are well represented by either rough hard-sphere or UNIDIF model. On the side, the infinite dilution diffusion coefficient has been found greater at lower glycol molecular weight, an observation that corroborates with the property''s dependence on free volume. [Copyright &y& Elsevier]

Abstract: The synthesis of propylene glycol (PG) and dipropylene glycol (DPG) was carried out by the hydrolysis of propylene oxide over solid base catalysts. Among them, sol–gel derived Na2O–ZrO2 showed the excellent performance. It was found that Na2O–ZrO2 had a mesoporous framework in which Na2O nanoparticles were homogeneously dispersed. Such a structure led to the strong basicity and then the excellent performance in the hydrolysis of propylene oxide. As a result, one-pot synthesis of propylene glycol (PG) and dipropylene glycol (DPG) could take place at a low H2O/PO ratio of 3 without any condensation reactions. [Copyright &y& Elsevier]