Propylene Glycol Research Articles

Rapid Determination of Trace Ethylene Glycol and Diethylene Glycol in Propylene Glycol-Contained Syrups by Ultrahigh-Performance Supercritical Fluid Chromatography-Mass Spectrometry after Precolumn Derivatization

Ethylene glycol (EG) and diethylene glycol (DEG) are two contaminants known to cause a variety of human health problems, when ingested in certain amounts, they can cause adverse effects such as nephrotoxicity, neurotoxicity and even death. They are widely found in propylene glycol, which is commonly used as a base for pharmaceutical syrups. The aim of this study was to develop an analytical method for the evaluation of EG and DEG in commercially available pediatric syrups. In this study, a fast, simple and reliable ultrahigh performance supercritical fluid chromatography-electrospray ionization-mass spectrometry (UHPSFC-ESI-MS) method was developed. The work involved the evaluation of three derivatization reagents for UHPSFC-ESI-MS. Benzoyl chloride was finally selected as the optimal derivatization reagent. Compared with an approach without derivatization, the present method achieved the separation and detection of EG and DEG efficiently, sensitively and rapidly, and analysis of EG and DEG in syrup formulations was realized within 7 min. The linear determination coefficients of EG and DEG in the concentration range of 0.25–25.0 μg/mL were greater than 0.999. The limits of detection for EG and DEG were 0.02 μg/mL and 0.07 μg/mL, respectively, and the limits of quantification were 0.09 μg/mL and 0.25 μg/mL, respectively. The recovery rates of DEG and EG ranged from 85.5%–108.1% and 86.7%–117.2%, respectively. The absolute values of the matrix effects in the three types of syrups considered were all less than 10%. Meanwhile, a gas chromatography-hydrogen flame ionization detection method was established for cross-testing of the analytical results. In 10 batches of syrup formulations, DEG was not detected by either method. The presence of EG was detected by UHPSFC-ESI-MS in only three batches, none of which exceeded 90.23 parts per million (ppm), with a mean absolute error of 5.95 ppm between the two sets of results. The developed UHPSFC-ESI-MS method was rapid, simple, efficient, sensitive and accurate for the determination of EG and DEG in genuine syrup formulations.

Topical delivery of baricitinib-impregnated nanoemulgel: a promising platform for inhibition of JAK -STAT pathway for the effective management of atopic dermatitis.

Baricitinib, an inhibitor of Janus kinase 1/2 receptors majorly involved in the dysregulation of immune responses in atopic dermatitis, is currently approved for managing atopic dermatitis in Europe. The delivery of baricitinib through oral route is associated to several adverse effects due to off-target effects. Therefore, the current study is aimed at formulation of baricitinib loaded nanoemulgel for evaluation of topical delivery potential in the treatment of atopic dermatitis. The baricitinib-loaded nanoemulsions (0.05 and 0.1% w/w) revealed an average globule size of 162.86 ± 0.37 and 173.66 ± 4.88nm respectively with narrow PDI. The optimized batch of baricitinib nanoemulsion was converted to nanoemulgel by the addition of the mixture of gel bases SEPINEO™ DERM and SEPINEO™ P 600 along with propylene glycol, resulting in pseudoplastic shear thinning behaviour. The optimized nanoemulgels have shown prominent retention of baricitinib in the skin along with permeation. The skin distribution study of coumarin-6 loaded nanoemulgel demonstrated high fluorescence in the epidermal layer. The western blot analysis revealed significant inhibition of phosphorylated signal transducers and activators of transcriptions 1 (##p < 0.01) and 3 (#p < 0.05) by application of 0.05 and 0.1% baricitinib nanoemulgel. The baricitinib nanoemulgels have shown anti-inflammatory activity by significantly reducing expressions of various inflammatory markers. Histopathological analysis of skin tissues treated with baricitinib nanoemulgel has demonstrated a marked reduction in acanthosis, hyperkeratosis, and intact outer epidermis. These results supported the potential role of baricitinib-loaded nanoemulgel in reducing the inflammation and disease severity associated with atopic dermatitis.

Towards value-added chemicals: Technical and environmental life cycle assessment evaluation of different glycerol valorisation pathways

Biodiesel is acknowledged as the most appropriate biofuel to decarbonise the transport sector and combat climate change. The ever-increasing biodiesel production via transesterification results in large amount of glycerol (e.g., 10 kg of glycerol for every 100 kg of biodiesel). Converting glycerol into value-added goods is perceived to be a viable way to lower the high cost of producing biodiesel and expand its market share. The current study examines the technical and environmental aspects of bio-hydrogen, bio-syngas, acrolein, propylene glycol, epichlorohydrin, bio-methanol and bio-ethanol synthesis. CHEMCAD process simulation software was used to perform the modelling and simulation aspects considering a glycerol flowrate of 100 kg/h. The environmental study is based on primary and secondary data and is carried out using the Life Cycle Assessment methodology and the LCA for Experts software, using ReCiPe as the impact assessment method. The technical evaluation points towards glycerol conversion to propylene glycol and bio-methanol production as the best approaches given the relatively low energy requirements, increased purity (>97 wt%) and steadily growing product market. Bio-methanol exhibits the best environmental performance among all examined scenarios, providing the lowest impact in eight out of eleven categories studied while placing second in terms of FETP impact. Glycerol conversion towards propylene glycol seems as the second-best conversion route as it generates the lowest score in regards to GWP impact (0.31 kg CO2 eq./ kgproduct). Ultimately, the most effective methods for valorizing glycerol and improving the production of biodiesel by lowering the expenses related to its manufacturing are glycerol reforming toward bio-methanol and propylene glycol.

Self-microemulsifying drug delivery system-based gastroretentive in situ raft of pazopanib with enhanced solubility and bioavailability.

Pazopanib hydrochloride (PZH) is a Biopharmaceutics Classification System class II drug that faces challenges at the formulation forefront including low aqueous solubility (0.043 mg/mL) and poor oral bioavailability (14-39%). The present investigation aimed to develop a self-microemulsifying drug delivery system (SMEDDS) of PZH using a blend of Capryol® 90, Labrasol®, and propylene glycol to improve its solubility. Furthermore, a sustained-release SMEDDS-based gastroretentive floating system was developed and optimized using the Central Composite Design approach of DoE. The optimized SMEDDS-based in situ gelling raft, R-SM-PZH, exhibited minimal floating lag time (3.09 ± 0.8 s), optimal viscosity (1229.4 ± 20.9 cP) and density (0.327 ± 0.15 g/mL) as compared to other formulations under study. Additionally, R-SM-PZH was evaluated for its in vitro dissolution in FaSSGF and FeSSGF, pharmacokinetic profile, and MTT assay (against NCI-H460 lung cancer cells) compared to pure PZH. A 12 h sustained release, three-fold augmentation in dissolution rate and bioavailability, and 15-fold enhancement in cytotoxicity were observed in comparison to pure PZH. Thus, the SMEDDS-based in situ gelling raft presents a promising approach to advancing the developability potential of PZH.

Biological Response after 14-Day Cannabidiol and Propylene Glycol Inhalation in Sprague-Dawley Rats.

Objective: Cannabidiol (CBD), a phytocannabinoid of increasing interest for its purported therapeutic effects, is primarily consumed via ingestion and inhalation. While the toxicology of orally administered CBD has been reported, little is known about the effects of CBD inhalation. Doses selected for the present analysis allowed for evaluation of dose-response at concentrations >100-fold higher than typical human consumption levels. Materials and Methods: CBD (98.89% pure) was formulated in propylene glycol (PG) and aerosolized by nebulization to evaluate biological response after nose-only inhalation. Sprague Dawley rats (n = 35 males, 30 females) were exposed to 1.0 and 1.3 mg/L nominal concentrations of CBD and PG, respectively, for 12-180 min. Resulting average daily presented dose ranges were 8.9-138.5 mg/kg CBD and 11.3-176.0 mg/kg PG. Aerosols of 1.4 µm median diameter were achieved. Biological response indicators included clinical signs, clinical chemistry, hematology, body/organ weights, and pulmonary/systemic histopathology. Results: Inflammatory and necrotic responses were observed in the nose at the highest doses of CBD. Limited findings in the larynx and lung were mainly observed at higher doses. There were no histological findings in extrapulmonary organs. Dosimetry modeling differentiated the no observable adverse effect level between the nasal region and lungs to be 2.8 and 10.6 mg/kg CBD, respectively. Conclusions: Dose-depending findings of histological changes in the respiratory tract are observed at high doses. At lower doses consistent with typical over-the-counter vape products there appears to be substantial safety margin in the present study (93- and 353-fold lower for nose and lung, respectively).

Permeability and Toxicity of Cryoprotective Agents in Silkworm Embryos: Impact on Cryopreservation

The permeation of cryoprotectants into insect embryos is critical for successful cryopreservation. However, the permeability of silkworm embryos to cryoprotectants and the effects of cryopreservation remain poorly studied. In this study, we evaluated the permeability and toxicity of four cryoprotective agents (CPAs) as well as the vitrification effect on the viability of silkworm embryos. Among the four CPAs, propylene glycol (PG) showed the best permeability. Ethylene glycol (EG) and PG were the least toxic CPAs, but glycerol (GLY) and dimethyl sulfoxide (DMSO) were more toxic. Moreover, we examined several factors including the kind and the concentration of CPAs, exposure time, embryonic stage, and silkworm strains. Embryos at the earlier phases of stage 25 were more tolerant to vitrification using EG. We found that over 21% of embryos treated with EG at the early 2 phase of stage 25: 163 h after egg laying (AEL) developed and progressed to serosa ingestion after vitrification and rewarming. The result was the same in other strains as well. Our results are valuable for the development of new cryopreservation protocols of silkworm embryos.

The effect of the composition of hepatoprotective action on biochemical and morphostructural changes in the body of laying hens under thermal stress

To reduce the negative effects of hyperthermia on the body of farm animals and poultry, various drugs and feed additives are currently used. Which do not have sufficiently adaptogenic and antitoxic properties. We studied the effect of a hepatoprotective composition consisting of dried live yeast, amorphous silicon dioxide, propylene glycol, calcium propionate, ascorbic acid, manganese, copper and zinc chelates, methionine and choline chloride on the variability of biochemical and morphological parameters of the body of laying hens under temperature stress. It was simulated by increasing the air temperature in a building where laying hens were kept from 18.0 ± 1.0 °C to 28.0 ± 1.0 °C for 48 hours. Due to hyperthermia, changes in biochemical and morphofunctional parameters were observed in the tissues and organs of birds. The obtained values of the biochemical parameters of blood serum in the birds of the control group indicated the intensity of the adaptive capabilities of their body. A complex of morphological changes confirmed a violation of protein metabolism and the regenerative-compensatory process. Pathological changes in the structure of the duodenum, characteristic of catarrhal-necrotic duodenitis, were identified. The stress reaction was also reflected in the condition of the heart muscle, in which an inflammatory process developed against the background of granular dystrophy of cardiomyocytes. The results of biochemical studies of blood serum in birds of the experimental group indicated an increase in the anti-stress response to a temperature stimulus under the influence of the studied composition (tendency to increase glucose and calcium, increase alkaline phosphatase activity by 47.4 %). The introduction of a hepatoprotective composition into the diet of laying hens during periods of temperature stress did not lead to disruption of the structure of tissues and organs, preserving cellular metabolic mechanisms. The

Impact of carbon sources in airport de-icing compounds on the growth of Sphaerotilus natans

Airport de-icing has been linked with the growth of undesirable river biofilms (URBs, formerly “sewage fungus”), a manifestation of organic pollution causing long-term ecological damage to watercourses. URBs are a polymicrobial community, with one key taxon standing out in literature: Sphaerotilus natans, a filamentous bacterium also found in sewage treatment and activated sludges. An industry often implicated in causing URBs is airport de-icing, with large biofilms often developing downstream of airport discharges in winter months. However, it is not yet clear which de-icers may cause URBs and how they influence growth. Therefore, specific objectives were to (i) determine which freeze-point depressants (FPDs) can be utilized by S. natans; (ii) examine differences in the growth kinetics between FPDs; and (iii) compare pure-FPDs to commercial airport de-icers (CADs) as carbon sources, to determine impacts of additives. This study employed a turbidimetric micro-batch culture design to conduct microbial growth experiments, using S. natans and a minimal medium supplemented with airport de-icer as the carbon source. Equimolar carbon concentrations were used to compare the effects of common FPDs and CADs – each containing a specific FPD. Growth was assessed via optical density (OD600) measurements, from which time-to-detection, maximum rate of change, and maximum optical density were derived and kinetics inferred. S. natans was found to grow effectively on all FPDs tested, although the microbial yield was heavily dependent on the carbon concentration for all FPDs and CADs. Sodium acetate generated the quickest growth, with the lowest TTD (lag-time) for all but the lowest concentrations tested. Propylene glycol produced the greatest maxOD (total growth), whereas ethylene glycol had a higher limiting concentration for maxROC (growth rate). The mixture of compounds and additives in commercial products did not significantly impact the growth of S. natans. This research provides evidence from controlled laboratory experiments that airport de-icers support the growth of S. natans. The differences in growth kinetics observed for the FPDs and CADs could inform improved mitigation or treatment to reduce the incidence and ecological impacts of URBs.

Solid-State Lithium Batteries with In Situ Polymerized Acrylate-Based Electrolytes Capable of Electrochemically Stable Operation at 100 °C.

Solid polymer electrolytes (SPEs) typically consist of salts with mobile anions that could cause instabilities and parasitic side reactions in solid-state lithium (Li) batteries. To address this challenge, single-Li-ion conducting (SLIC) SPEs, where anions of Li salts are covalently attached to the polymer backbone, have been utilized to reduce the number of mobile anions. This approach improves the cationic transference number but is accompanied by a loss of ionic conductivity. In this work, we investigate a synergetic approach of using both a polymerizable SLIC salt and a conventional Li salt in a polymer matrix by in situ polymerization of the poly(propylene glycol) acrylate (PPGA) monomer. The synthesized hybrid SPEs show a high ionic conductivity of up to ∼2 × 10-4 S cm-1 and a relatively high Li-ion transference number of ∼0.4. With a significantly reduced fraction of mobile anions in the combined salt SPE, in situ polymerized SPE cells with a LiFePO4 (LFP) cathode achieve a stable performance for over 100 cycles at temperatures as high as 100 °C, which is unattainable with conventional Li salts or electrolytes. Furthermore, solid-state nuclear magnetic resonance spectra provide additional insights into differences in Li nucleus environments and emphasize a reduction in activation energy for hybrid SPEs due to their more open structure. This study opens the path for the fabrication of high-performance solid polymer Li batteries capable of operating at high temperatures using commercial battery fabrication equipment, as in situ polymerized acrylate-based polymers provide drop-in compatibility with conventional battery production, ease of acrylate polymerization, and inexpensive, facile SPE chemistry. We expect that further tuning of the acrylate-based SPE composition may allow further increases in its conductivity without sacrificing its electrochemical stability or mechanical properties.

Liquid vortex surface deformation probed by light reflection

Abstract We propose a method that combines an optical system with image processing techniques to scrutinize the dependence of liquid vortex deformation on varying angular velocity based on light reflection on liquid surfaces due to dynamic wettability. In our experiment, a broadened and collimated laser beam is directed onto curved surfaces, providing information on the vortex parameters through the analysis of the reflected beam profile. Additionally, the physical model of the liquid surface in a rotating cylinder before dewetting is examined. We investigate the liquid vortex forms of a saline solution and propylene glycol across various angular velocities, comparing them to the ideal parabolic vortex surface shape. The results show that, under the same experimental conditions, the vortex profiles of both solutions are equivalent. The vortex surface shape at certain angular velocity values, as determined by fitting plots, closely resembles a parabola, with R2 &gt; 99%. The proposed method introduces a new approach for characterizing the dynamics of liquids as well as monitoring natural phenomena.

Modelling Analysis of Propylene Glycol as a Cooling Media for Battery Thermal Management System in Electric Vehicles

Modelling Analysis of Propylene Glycol as a Cooling Media for Battery Thermal Management System in Electric Vehicles

Exploring the Impact of Developmental Clearance Saturation on Propylene Glycol Exposure in Adults and Term Neonates Using Physiologically Based Pharmacokinetic Modeling.

Propylene glycol (PG) is a pharmaceutical excipient which is generally regarded as safe (GRAS), though clinical toxicity has been reported. PG toxicity has been attributed to accumulation due to saturation of the alcohol dehydrogenase (ADH)-mediated clearance pathway. This study aims to explore the impact of the saturation of ADH-mediated PG metabolism on its developmental clearance in adults and neonates and assess the impact of a range of doses on PG clearance saturation and toxicity. Physiologically based pharmacokinetic (PBPK) models for PG in adults and term neonates were developed using maximum velocity (Vmax) and Michaelis-Menten's constant (Km) of ADH-mediated metabolism determined in vitro in human liver cytosol, published physicochemical, drug-related and ADH ontogeny parameters. The models were validated and used to determine the impact of dosing regimen on PG clearance saturation and toxicity in adults and neonates. The Vmax and Km of PG in human liver cytosol were 1.57 nmol/min/mg protein and 25.1 mM, respectively. The PG PBPK model adequately described PG PK profiles in adults and neonates. The PG dosing regimens associated with saturation and toxicity were dependent on both dose amount and cumulative in standard dosing frequencies. Doses resulting in saturation were higher than those associated with clinically observed toxicity. In individuals without impaired clearance or when PG exposure is through formulations that contain excipients with possible interaction with PG, a total daily dose of 100-200 mg/kg/day in adults and 25-50 mg/kg/day in neonates is unlikely to result in toxic PG levels or PG clearance saturation.

FORMULATION OF SELF-NANO EMULSIFYING SYSTEM (SNES) CONTAINING SNAKEHEAD FISH EXTRACT PROTEIN INCORPORATED INTO CORN OIL BY HYDROPHOBIC ION PAIRING METHOD

Objective: The purpose of this study was to determine whether the protein complexation of snakehead fish extract using the hydrophobic ion pairing method with Sodium Dodecyl Sulfate (SDS) as a complexing ligand could be loaded into the corn oil component of the SNES and to explore the ratio of oil, surfactant, and cosurfactant in the Self-Nanoemulsifying System (SNES) formula that can produce good SNES characteristics. Methods: Snakehead fish proteins were extracted using pressurized hot water and then complexed with SDS at acidic pH. The SDS-protein complex was loaded into the oil component of the SNES and then combined with the surfactant component (Tween 80) and cosurfactant (propylene glycol) in a ratio of 1:9:1, which, based on the preliminary miscibility screening, has the best miscibility among other screening results. Results: The results of the study were as follows. The binding efficiency of the SDS-protein-complex was 31.74% and the loading efficiency into SNES was 83.17%. The nanoemulsion formed had visible light transmittance of 100.4%, particle size 72.7 nm, zeta potential-53.03 mV, and emulsification time 71.67 seconds. The nanoemulsion was stable at storage and 100 and 1000 times dilution challenges using aqueous media, Simulated Gastric Fluid (SGF), and Simulated Intestinal Fluid (SIF). Conclusion: The hydrophobic ion-pair complexation of snakehead fish protein extract with SDS as the complexing ligand was able to load the protein into the oil component of SNES and the ratio of oil, surfactant, and cosurfactant in the SNES formula that produce good SNES characteristics was corn oil, Tween 80, and propylene glycol at a ratio of 1:9:1

A rare and underestimated cause of anion gap metabolic acidosis in a pediatric patient

Abstract Recognized causes of anion gap metabolic acidosis include methanol, uremia, diabetic ketoacidosis, propylene glycol, isoniazid, iron, lactic acidosis, ethylene glycol, and salicylates, which is taught as the mnemonic, MUDPILES. While this mnemonic can be a useful learning tool, it is important to consider other, atypical causes. Here, we present the case of a 9-year-old male patient with a complex medical history, including trisomy 21 and Lennox-Gastaut syndrome who presented to the emergency department (ED) in hypotensive shock. Upon admission, he was noted to have a distended abdomen, evidence of acute pancreatitis and possible sepsis. Of note, his initial labs revealed an anion gap of 30.1 mmol/L, a whole blood lactate of 4.4 mmol/L, a pH of 7.2, and a normal pCO2, indicting an anion gap metabolic acidosis. Importantly, methanol, ethylene glycol, ketones, and salicylates were not detected, and renal function was normal. However, he did have an extensive medication history, including several antiepileptic drugs (AEDs). Over the coming weeks, he recovered from the acute pancreatitis, but developed fluid overload, electrolyte derangements (hypernatremia and hypokalemia), a worsening metabolic acidosis with an anion gap up to 54.6 mmol/L, and hyperammonemia (plasma NH3 of 232 μmol/L). At this point, the metabolism team was contacted for concerns regarding the rising ammonia levels, which subsequently responded to a combination of lactulose and Rifaximin. An inborn error of metabolism (IEM) was considered, and plasma amino acid analysis was performed (Waters Acquity MassTrak AAA solution) but was not diagnostic. Notably, the patient developed a significantly elevated gamma glutamyl transpeptidase (GGT) up to 4088 U/L, suggesting glutathione depletion, however, transaminases and alkaline phosphatase were normal. The laboratory was contacted by the metabolism providers for other possible causes of metabolic acidosis and it was suggested that the patient undergo urine organic acid testing. Urine specimens were analyzed using gas chromatography/mass spectrometry (GC/MS) (Aligent system). The results were notable for marked excretion of pyroglutamic acid (5-oxoproline), which is typically associated with acetaminophen, however, the patient’s acetaminophen levels were less than 5 μg/mL, indicating another, atypical cause of increased pyroglutamic acid. In this case, vigabatrin, an anticonvulsant known to cause glutathione depletion and secondary pyroglutamic aciduria was suspected, and subsequently withdrawn. The patient was also started on a trial of N-acetylcysteine (NAC) to replenish glutathione, which resolved the pyroglutamic aciduria and anion gap, and corrected the metabolic acidosis. This case highlights the importance of recognizing pyroglutamic acid as a rare cause of anion gap metabolic acidosis, even in the setting of normal acetaminophen levels, and the importance of organic acid testing in the work-up of such patients. Wider use of the mnemonic GOLD MARK, where the “O” stands for oxoproline, may help in the differential diagnosis of anion gap metabolic acidosis.

OPTIMIZATION ULTRASOUND-ASSISTED EXTRACTION USING CHOLINE CHLORIDE-BASED NATURAL DEEP EUTECTIC SOLVENT TO INCREASE PHENOLIC COMPOUNDS AND ANTIOXIDANTS FROM RHODOMYRTUS TOMENTOSA LEAVES

Objective: The main purpose of this study is to give recommendations for the ideal extraction conditions for improving the extraction yield and antioxidant activity of R. tomentosa leaves. Methods: First, the extraction total phenolic yields of five choline chloride-based Natural Deep Eutectic Solvents (NADES) were evaluated. Then, Box Behnken designs of Response Surface Methodology (RSM) were conducted in order to optimize the extraction condition. The extraction variables investigated were extraction time, water content in NADES, and solid-to-liquid ratio. Meanwhile, total phenolic and 2,2′-azinbis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) free radicals scavenging activity were used as responses. Results: NADES with combination of choline chloride and propylene glycol with a molar ratio of 1:1 was found to be the best solvent for extracting phenolic compound. The total phenolic compound obtained was 29.6351 mg GAE/g dried leaves with ABTS scavenging activity about 96.84% under the optimum extraction condition (extraction time of 60 min, 25% water content in NADES, and solid-to-liquid ratio of 0.02 g/ml). Better results were shown compared to extracts with conventional solvents. Conclusion: In sum, the use of choline chloride-based NADES as extraction solvent under optimum condition was proven to be effective in increasing the extraction efficiency of phenolic compounds and antioxidant activity from R. tomentosa leaves.

A Total Internal Reflection Microscopy (TIRM)-Based Approach for Direct Characterization of Polymer Brush Conformational Change in Aqueous Solution.

This study presents a novel approach utilizing total internal reflection microscopy (TIRM) to effectively characterize the swelling and collapse of polymer brushes in aqueous solutions. Zwitterionic poly(carboxybetaine methacrylate) (PCBMA) and nonionic poly[oligo(ethylene glycol) methyl ether methacrylate] (POEGMA) brushes are chosen as model systems. By investigation of an intriguing theory-experiment discrepancy observed during the measurement of near-wall hindered diffusion, valuable insights into the compressibility of polymer brushes are obtained, revealing their conformational information in aqueous solution. The results demonstrate that zwitterionic PCBMA brushes exhibit minimal antipolyelectrolyte effects in 0.1-10 mM NaCl solution but undergo significant swelling with increasing pH. On the other hand, nonionic POEGMA brushes exhibit similar responses to ionic strength as weak polyelectrolyte brushes. These unexpected findings enhance our understanding of polymer brushes beyond classical theories. The TIRM-based approach proves to be effective for characterizing polymer brushes and other soft nanomaterials.

Poly(lactide) Upcycling Approach through Transesterification for Stereolithography 3D Printing.

The legislature determines the recycled and waste contents in fabrication processes to ensure more sustainable production. PLA's mechanical recycling and reuse are limited due to the performance decrease caused by thermal or hydrolytic instability. Our concept introduces an upcycling route involving PLA depolymerization using propylene glycol as a reactant, followed by the methacrylation, assuring the liquid systems' curability provided by radical polymerization. PLA-containing curable systems were studied from a rheological and thermomechanical viewpoint. The viscosity levels varied from 33 to 3911 mPa·s at 30 °C, giving a wide capability potential. The best system reached 2240 MPa storage modulus, 164.1 °C glass-transition temperature, and 145.6 °C heat-resistant index, competitive values to commercial systems. The printability was verified for all of the systems. Eventually, our concept led to SLA resin production containing PLA waste content up to 51 wt %.

Isoorientin Improves Excisional Skin Wound Healing in Mice

Background/Objectives: Wound healing relies on a coordinated process with the participation of different mediators. Natural products are a source of active compounds with healing potential. Isoorientin is a natural flavone recognized as having several pharmacological properties, such as anti-inflammatory effects, making it a potential treatment for wounds. We investigated the effect of isoorientin on the healing of excisional skin wounds. Methods: Male Swiss mice were subjected to the induction of excisional skin wounds (6 mm diameter) and treated with a vehicle (2% dimethyl sulfoxide in propylene glycol) or 2.5% isoorientin applied topically once a day for 14 days. The wound area was measured on days 0, 3, 7, and 14. Histopathological analyses were performed on the cicatricial tissue after 14 days. The myeloperoxidase activity and the interleukin-1β, tumoral necrosis factor (TNF)-α, and interleukin-6 concentrations were determined on the third day. Results: We observed that 3 days after the topical application of isoorientin, the lesion area was significantly smaller when compared to those of the vehicle (p &lt; 0.01) and control (p &lt; 0.05) groups. No difference was observed after 7 and 14 days of induction. Despite this, on day 14, histological analysis of cicatricial tissue from the animals treated with isoorientin showed reduced epidermal thickness (p &lt; 0.001) and increased collagen deposition (p &lt; 0.001). These effects were accompanied by decreased myeloperoxidase activity and interleukin-1β concentration on the third day of induction, without alteration in TNF-α and interleukin-6. Conclusions: The treatment with isoorientin promoted better tissue repair in excisional wounds in mice, which may be linked to the modulation of the early inflammatory response.

Simulation and optimization of DMC synthesis process based on conventional and advanced exergy analyses

Dimethyl carbonate has received more and more attentions as an organic solvent in electrolytes. Aiming at the problem of high energy consumption in the process of dimethyl carbonate (DMC) production, the root of the problem was analyzed by using exergy analysis, which provides a theoretical basis for the construction of energy-saving process. Firstly, the overall process of DMC production was constructed, including propylene carbonate (PC) synthesis, DMC synthesis, azeotrope separation and propylene glycol (PG) purification processes. Secondly, the conventional and advanced exergy analyses of the four proposed processes were carried out. The distributions of exergy and exergy destruction were obtained through conventional exergy analysis. The exergy destructions were further divided through advanced exergy analysis, and the avoidable parts were focused on. Based on the above analyses, the corresponding heat integration processes were proposed. Finally, the conventional processes and the heat integration processes were evaluated with the performance indicators of the exergy destruction, total annual cost (TAC), total energy consumption (TEC) and CO2 emissions.

Synthesis of vitamin D3 loaded ethosomes gel to cure chronic immune-mediated inflammatory skin disease: physical characterization, in vitro and ex vivo studies

The purpose of the current work was to develop and characterize ethosomes of vitamin D3 gel that could more effectively work against psoriasis. Psoriasis is a chronic immune-mediated inflammatory skin disease. Due to vitamin D3 role in proliferation and maturation of keratinocytes, it has become an important local therapeutic option in the treatment of psoriasis. In this research we have initiated worked on ethosomes gels containing vitamin D3 to treat psoriasis. Soya lecithin 1–8% (w/v), propylene glycol and ethanol were used to create the formulations, which were then tested for vesicle size, shape, surface morphology, entrapment effectiveness, and in vitro drug permeation. The drug encapsulation efficiency of ethosomes was 96.25% ± 0.3. The particle sizes of the optimized ethosomes was 148 and 657 nm, and the PDI value was 0.770 ± 0.12 along with negative charge − 14 ± 3. Fourier transform infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC) along with thermogravimetric analysis (TGA) studies confirmed the absence of interactions between vitamin D3 and other ingredients. It was determined that the total amount of medication that penetrated the membrane was 95.34% ± 3. Percentage lysis was very negligible for all strengths which were found less than 15%. Based on our research, ethosomes appear to be safe for use. The vitamin D3 ethosomal gel order, description, pH, and viscosity were all within the specified ranges, according to the findings of a 6-month investigation into the stability profile of the completed system. In this research, we successfully prepared ethosomes loaded with vitamin D3 and then converted it into gel for patients’ easy applications.