Effects of Ionic Liquids on the Cylindrical Self-Assemblies Formed by Poly(ethylene oxide)-Poly(propylene oxide)-Poly(ethylene oxide) Block Copolymers in Water

Aiming at the fundamental understanding of solvent effects in amphiphilic polymer systems, we considered poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) block copolymers in water mixed with an ionic liquid-ethylammonium nitrate (EAN), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6), or 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4)-and we investigated the hexagonal lyotropic liquid crystal structures by means of small-angle X-ray scattering (SAXS). At 50% polymer, the hexagonal structure (cylinders of self-assembled block copolymer) was maintained across the solvent mixing ratio. The effects of the ionic liquids were reflected in the characteristic length scales of the hexagonal structure and were interpreted in terms of the location of the ionic liquid in the self-assembled block copolymer domains. The protic ionic liquid EAN was evenly distributed within the aqueous domains and showed no affinity for the interface, whereas BMIMPF6 preferred to swell PEO and was located at the interface so as to reduce contact with water. BMIMBF4 was also interfacially active, but to a lesser extent.

A Survey of the Union of European Neonatal and Perinatal Societies on Neonatal Respiratory Care in Neonatal Intensive Care Units

(1) Background: Our survey aimed to gather information on respiratory care in Neonatal Intensive Care Units (NICUs) in the European and Mediterranean region. (2) Methods: Cross-sectional electronic survey. An 89-item questionnaire focusing on the current modes, devices, and strategies employed in neonatal units in the domain of respiratory care was sent to directors/heads of 528 NICUs. The adherence to the "European consensus guidelines on the management of respiratory distress syndrome" was assessed for comparison. (3) Results: The response rate was 75% (397/528 units). In most Delivery Rooms (DRs), full resuscitation is given from 22 to 23 weeks gestational age. A T-piece device with facial masks or short binasal prongs are commonly used for respiratory stabilization. Initial FiO2 is set as per guidelines. Most units use heated humidified gases to prevent heat loss. SpO2 and ECG monitoring are largely performed. Surfactant in the DR is preferentially given through Intubation-Surfactant-Extubation (INSURE) or Less-Invasive-Surfactant-Administration (LISA) techniques. DR caffeine is widespread. In the NICUs, most of the non-invasive modes used are nasal CPAP and nasal intermittent positive-pressure ventilation. Volume-targeted, synchronized intermittent positive-pressure ventilation is the preferred invasive mode to treat acute respiratory distress. Pulmonary recruitment maneuvers are common approaches. During NICU stay, surfactant administration is primarily guided by FiO2 and SpO2/FiO2 ratio, and it is mostly performed through LISA or INSURE. Steroids are used to facilitate extubation and prevent bronchopulmonary dysplasia. (4) Conclusions: Overall, clinical practices are in line with the 2022 European Guidelines, but there are some divergences. These data will allow stakeholders to make comparisons and to identify opportunities for improvement.

Dr. Tetsuro Fujiwara-My Memories from the Early Days of Dr. Fujiwara's Research

This brief commentary honors Dr. Tesuro Fujiwara, the first person to treat infants with respiratory distress syndrome by instilling surfactant into their trachea. In the 1960s, mortality from RDS, which could only be treated with oxygen, was about 50 percent. Based on the physiology Fujiwara learned that lung immaturity could be treated with doses of surfactant from animals in sheep models. He then made a surfactant from cow lungs called Servanta and treated 10 infants with RDS, who all had a large improvement in oxygenation. Other new therapies, such as continuous positive airway pressure and newer infant ventilators-in combination with surfactant therapy have decreased infant mortality to less than 1% from RDS in the most recent US infant death statistics.

Fabricating Polymer/Surfactant/Cyclodextrin Hybrid Particles for Possible Nose-to-Brain Delivery of Ropinirole Hydrochloride: In Vitro and Ex Vivo Evaluation

Ropinirole is a non-ergolinic dopamine agonist used to manage Parkinson's disease and it is characterized by poor oral bioavailability. This study aimed to design and develop advanced drug delivery systems composed of poloxamer 407, a non-ionic surfactant (Tween 80), and cyclodextrins (methyl-β-CD or hydroxy-propyl-β-CD) for possible brain targeting of ropinirole after nasal administration for the treatment of Parkinson's disease. The hybrid systems were formed by the thin-film hydration method, followed by an extensive physicochemical and morphological characterization. The in vitro cytotoxicity of the systems on HEK293 cell lines was also tested. In vitro release and ex vivo mucosal permeation of ropinirole were assessed using Franz cells at 34 °C and with phosphate buffer solution at pH 5.6 in the donor compartment, simulating the conditions of the nasal cavity. The results indicated that the diffusion-controlled drug release exhibited a progressive increase throughout the experiment, while a proof-of-concept experiment on ex vivo permeation through rabbit nasal mucosa revealed a better performance of the prepared hybrid systems in comparison to ropinirole solution. The encouraging results in drug release and mucosal permeation indicate that these hybrid systems can serve as attractive platforms for effective and targeted nose-to-brain delivery of ropinirole with a possible application in Parkinson's disease. Further ex vivo and in vivo studies to support the results of the present work are ongoing.

Study on the Performance Mechanism of Polyformaldehyde Glycol Ether Polymer for Crude Oil Recovery Enhancement

The demand for energy continues to increase as the global economy continues to grow. The role of oilfield chemicals in the process of oil and gas exploration, development, and production is becoming more and more important, and the demand is rising year by year. The support of national policies and the formulation of environmental protection regulations have put forward higher requirements for oilfield chemical products, which has promoted the innovative research and development and market application of oilfield chemicals. Polyformaldehyde glycol ether polymer (PGEP) is simple to synthesize, easily biodegradable, green and environmentally friendly, and in line with the development trend of chemicals used in oil and gas development. The interfacial tension performance of PGEP after compounding with different surfactants can reach as low as 0.00034 mN/m, which meets the requirements of the oilfield (interfacial tension ≤ 5 × 10-3 mN/m). The best oil washing efficiency performance of PGEP compounded with different surfactants reached 78.2%, which meets the requirements of the oilfield (oil washing efficiency ≥ 40%). The fracturing fluid drainage efficiency of PGEP after compounding with different surfactants reaches 22%, which meets the requirements of the oilfield (drainage efficiency ≥ 15%). The surface interfacial tension of the system remains constant after the concentration exceeds 0.2% and decreases with lower concentrations. The drainage efficiency increases with increasing concentrations in the range below 0.6%. It was determined that PGEP can be used as a surfactant instead of fatty-alcohol ethoxylates (FAE) in oilfield development.

The Electrical and Mechanical Characteristics of Conductive PVA/PEDOT:PSS Hydrogel Foams for Soft Strain Sensors

Conductive hydrogels are of interest for highly flexible sensor elements. We compare conductive hydrogels and hydrogel foams in view of strain-sensing applications. Polyvinyl alcool (PVA) and poly(3,4-ethylenedioxythiophene (PEDOT:PSS) are used for the formulation of conductive hydrogels. For hydrogel foaming, we have investigated the influence of dodecylbenzenesulfonate (DBSA) as foaming agent, as well as the influence of air incorporation at various mixing speeds. We showed that DBSA acting as a surfactant, already at a concentration of 1.12wt%, efficiently stabilizes air bubbles, allowing for the formulation of conductive PVA and PVA/PEDOT:PSS hydrogel foams with low density (<400 kg/m3) and high water uptake capacity (swelling ratio > 1500%). The resulting Young moduli depend on the air-bubble incorporation from mixing, and are affected by freeze-drying/rehydration. Using dielectric broadband spectroscopy under mechanical load, we demonstrate that PVA/PEDOT:PSS hydrogel foams exhibit a significant decrease in conductivity under mechanical compression, compared to dense hydrogels. The frequency-dependent conductivity of the hydrogels exhibits two plateaus, one in the low frequency range, and one in the high frequency range. We find that the conductivity of the PVA/PEDOT:PSS hydrogels decreases linearly as a function of pressure in each of the frequency regions, which makes the hydrogel foams highly interesting in view of compressive strain-sensing applications.

Exploring the behavior of Candida antarctica lipase B in aqueous mixtures of an imidazolium ionic liquid and its surfactant analogue

The performance of Candida antarctica lipase B (CALB) has been evaluated in 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4)/water mixtures in a wide range of molar fractions (χ B M I M B F 4 ) with and without 1-dodecyl-3-methylimidazolium tetrafluoroborate (C12-MIMBF4), a surfactant derived from BMIMBF4. The main aim of this work is to evaluate the influence of χ B M I M B F 4 over micellar aggregates to assess the activity of enzymatic reactions. The investigated reaction corresponds to the hydrolysis of the substrate p-nitrophenyl laureate in each χ B M I M B F 4 . The kinetic study for χ B M I M B F 4 at around 0.2 proved to be a border point in enzymatic activity. At χ B M I M B F 4 = 0.1, the lipase activity increases in the presence of C12-MIMBF4. However, at higher concentrations, BMIMBF4 has a negligible effect over the lipase activity. These results suggest specific interactions between water and BMIMBF4 molecules in relation to CALB. This research highlights the superactivity phenomenon driven by the reaction media and the micelle interface. In this interfacial interaction, BMIMBF4 acts directly on the changes induced on the enzyme upon its interaction with the micellar interface. This study opens a green perspective toward the biocatalysis field.

Fabrication of Oleophilic Polypeptide Nanoparticle from Complexing of Cross-Linked Epsilon-poly-l-lysine with Docusate Sodium for Preparation of Bactericidal Thermoplastic Polyurethanes

Thermoplastic polyurethanes (TPUs) are extensively utilized in the biomedical field due to their exceptional mechanical properties and biocompatibility. However, the lack of antibacterial activity limits their application ranges. Nanoscopic particle-based additives with inherent antibacterial characteristics are regarded as promising strategies to prevent biomaterials-associated infection. Herein, a novel polymeric nanoparticle is prepared, which integrates chemically cross-linked epsilon-poly-l-lysine (CPL) and anionic surfactant-docusate sodium (DS). The cross-linked epsilon-poly-l-lysine/docusate sodium (CPL/DS) nanoparticle can be well dispersed in organic solvent and a polymer matrix, which is beneficial to endowing TPUs with synergistic miscibility and antibacterial properties. An antibacterial test showed that the CPL/DS nanoparticles have strong antibacterial activity against S. aureus. Moreover, the results of antibacterial experiments in vitro revealed that almost 100% of S. aureus could be killed by CPL/DS nanoparticle-embedded TPU film with a content of 0.5 wt %. In addition, all of the CPL/DS modified TPU films showed good cytocompatibility in vitro. Consequently, this kind of CPL/DS nanoplatform has great potential to serve as a safe and high-efficient bactericidal agent for endowing biomedical devices with bactericidal property.

Less Invasive Surfactant Administration (LISA) Versus INSURE Method in Preterm Infants: a Retrospective Study

Background

Respiratory distress syndrome (RDS) is a major cause of morbidity and mortality in preterm infants. Early nasal CPAP and selective administration of surfactant via the endotracheal tube are widely used in the treatment of RDS in preterm infants.

Objective

The aim of this study was to compare the need for intubation and mechanical ventilation after surfactant delivery between LISA-treated and INSURE-treated premature infants with respiratory distress syndrome (RDS).

Methods

Retrospective registry-based cohort study enrolled 36 newborns admitted to the neonatal intensive care unit of the "Santa Maria" Hospital of Terni between 2016 and 2023. As a primary outcome, we followed the need for intubation and mechanical ventilation within 72 hours of life, while the secondary outcomes were major neonatal morbidities and death before discharge.

Results

The LISA group and the INSURE group included 13 and 23 newborns respectively. Demographic features showed no significant differences between the two groups. The need for mechanical ventilation in the first 72 hours of life was similar in both groups (p >0.99). There were no significant differences in morbidities.

Conclusion

LISA and INSURE are equally effective modalities for surfactant administration for the treatment of RDS in preterm infants.

Lipid Nanocapsule: A Novel Approach to Drug Delivery System Formulation Development

Nanocapsules are polymeric nanoparticles encased in a polymeric coating composed of a predominantly non-ionic surfactant, macromolecules, phospholipids, and an oil core. Lipophilic drugs have been entrapped using various nanocarriers, including lipid cores, likely lipid nanocapsules, solid lipid nanoparticles, and others. A phase inversion temperature approach is used to create lipid nanocapsules. The PEG (polyethyleneglycol) is primarily utilised to produce nanocapsules and is a critical parameter influencing capsule residence time. With their broad drug-loading features, lipid nanocapsules have a distinct advantage in drug delivery systems, such as the capacity to encapsulate hydrophilic or lipophilic pharmaceuticals. Lipid nanocapsules, as detailed in this review, are surface modified, contain target-specific patterns, and have stable physical and chemical properties. Furthermore, lipid nanocapsules have target-specific delivery and are commonly employed as a marker in the diagnosis of numerous illnesses. This review focuses on nanocapsule synthesis, characterisation, and application, which will help understand the unique features of nanocapsules and their application in drug delivery systems.

Correlation between Hydration States and Self-assembly Structures of Phospholipid and Surfactant Studied by Terahertz Spectroscopy

Phospholipids and surfactants form membranes and other self-assembled structures in water. However, it is not fully understood how the surrounding water (hydration water) is involved in their structure formation. In this paper, I summarize the results of our investigation of the long-range hydration state of phospholipids and surfactants at their surfaces by means of terahertz spectroscopy. By observing the collective rotational dynamics of water in the picosecond time scale, this technique allows us to observe not only the water directly bound to the solute, but also the weakly affected water outside of it. For example, PC phospholipids inhibit water dynamics over long distances, whereas PE phospholipids make water more mobile than bulk water. The causes of this difference in hydration and how it is involved in the structural formation of the membrane are reviewed.

Analysis of Cleaning Power Using New Cleaning Kinetics and Interfacial Science Studies on Aquatic Toxicity of Surfactants

Studies devised through the fusion of cleaning and environmental sciences can be summarized as follows: new cleaning kinetics applying a probability density function and a surface chemical approach to the aquatic toxicity of surfactants. Cleaning power analysis using the probability density functional method combines conventional cleaning kinetics using a first-order reaction equation with a risk analysis method using a probability density function. It is possible to analyze the cleaning mechanism from the obtained parameter values. It is also possible to determine whether the interaction between two different cleaning elements corresponds to a synergistic, additive, or offsetting effect. Studies on the aquatic toxicity of surfactants have focused on the surface tension at which surfactants exhibit toxicity, changes in toxicity due to water quality, and biodegradation, and the presence of adsorbed substances have been identified.

Adhesive properties of Aphrophoridae spittlebug foam

Aphrophora alni spittlebug nymphs produce a wet foam from anal excrement fluid, covering and protecting themselves against numerous impacts. Foam fluid contact angles on normal (26°) and silanized glass (37°) suggest that the foam wets various substrates, including plant and arthropod surfaces. The pull-off force depends on the hydration state and is higher the more dry the fluid. Because the foam desiccates as fast as water, predators once captured struggle to free from drying foam, becoming stickier. The present study confirms that adhesion is one of the numerous foam characteristics resulting in multifunctional effects, which promote spittlebugs' survival and render the foam a smart, biocompatible material of biological, biomimetic and biomedical interest. The sustainable 'reuse' of large amounts of excrement for foam production and protection of the thin nymph integument suggests energetic and evolutionary advantages. Probably, that is why foam nests have evolved in different groups of organisms, such as spittlebugs, frogs and fish.

Surfactant administration methods for premature newborns: LISA vs. INSURE comparative analysis

INTRODUCTION

Respiratory Distress Syndrome (RDS) is the most common respiratory disorder among premature infants. The use of surfactant has significantly reduced respiratory complications and mortality. There are two conventional methods for administering surfactant: Intubate-Surfactant-Extubate (INSURE) and Less Invasive Surfactant Administration (LISA). This study aims to compare the effects of surfactant administration using these two methods on the treatment outcomes of premature newborns.

MATERIALS AND METHODS

In this retrospective cohort study, we included 100 premature newborns with RDS and spontaneous breathing who were admitted to the Neonatal Intensive Care Unit of Besat Hospital in Sanandaj city in 2021. Exclusion criteria comprised congenital anomalies and the needing for intubation for resuscitation at birth. The outcomes of epmericaly trated with two methods were compared: the LISA (50 neonates) and the INSURE (50 neonates). Our interesting outcomes were needing for mechanical ventilation, duration of ventilation, pneumothorax, pulmonary hemorrhage, severe retinopathy, CPAP duration, and bronchopulmonary dysplasia. Finally, we entered the data into STATA-14 statistical software and analyzed it using chi-square and t-tests.

RESULTS

In this study, 69% of the neonates were boys. The LISA group exhibited significantly lower rates of need for mechanical ventilation (P = 0.003) and ventilation duration (P < 0.001) compared to the INSURE group. Conversely, there were no significant differences between the two groups (P > 0.05) in terms of pneumothorax, pulmonary hemorrhage, severe retinopathy, CPAP duration, and bronchopulmonary dysplasia rates.

CONCLUSION

The results of this study suggest that the LISA method is a safe and non-invasive approach for surfactant administration. Notably, it resulted in a reduced need for mechanical ventilation and decreased ventilation duration compared to the INSURE method.

Accelerated Recombination of Lophyl Radicals in Micelles: Rapid Controlled Self-Assembly of Micelles Formed by Amphiphilic Lophine Dimers and Release of Solubilized Substance by Photoirradiation

Controlling the morphology of molecular assemblies formed by surfactants by photoirradiation enables the controlled release of incorporated substances, which can be applied to delivery systems for drugs and active ingredients. On the other hand, conventional photoresponsive surfactants and molecular assemblies have a slow response speed, making it difficult to control their functions at the desired time. In this review, I discuss our recent progress in the accelerated control of functions of photoresponsive molecular assemblies by using lophine dimer as a photochromic compound. The lophine dimer derivative dissociates into a pair of lophyl radicals that upon ultraviolet (UV) light irradiation, and these radical species thermally recombine although the recombination reaction is extremely slow due to the diffusion of lophyl radicals. By using the confined inner space of micelles formed by surfactants, the recombination reaction was extremely accelerated. With UV light irradiation, rapid morphological changes in micelles, formed by amphiphilic lophine dimers were observed by using in situ small-angle neutron scattering (in situ SANS) system. Moreover, the rapid controlled release of calcein as a model drug was achieved by UV light irradiation using the photoresponsive micelles. This rapid system can realize the controlled release of drugs truly at the desired time, developing an efficient and precise drug delivery system (DDS). Furthermore, it can be applied in a wide range of fields such as release control of active ingredients, efficient heat exchange control, and actuating systems.

Neutron Activation Analysis of Rare Earth Element Extraction from Solution through a Surfactant-Assisted Dispersion of Carbon Nanotubes

We report the preparation of surfactant-assisted carbon nanotube dispersions using gum arabic, Triton X-100, and graphene oxide as dispersing agents for removing rare earth elements in an aqueous solution. The analytical tools, including (a) scanning electron microscopy and (b) neutron activation analysis, were utilized for qualitative and quantitative examinations, respectively. Neutron activation analysis was employed to quantitatively determine the percent of extraction of nuclides onto the carbon structure, while the images produced from the scanning electron microscope allowed the morphological structure of the surfactant-CNT complex to be analyzed. This report tested the effects responsible for nuclide removal onto CNTs, including the adsorbent to target mass ratio, the CNT concentration and manufacturing process, the pH, and the ionic radius. Observable trends in nuclide extraction were found for each parameter change, with the degree of dispersion displaying high dependency.

Photoluminescent Layered Crystal Consisting of Anderson-Type Polyoxometalate and Surfactant toward a Potential Inorganic-Organic Hybrid Laser

The hybridization of inorganic and organic components is a promising strategy to build functional materials. Among several functions, luminescence is an important function which should be considered for practical usage. Inorganic-organic hybrid luminescent materials have been investigated as phosphors, sensors, and lasers. Organic luminescent centers such as dye molecules have often been hybridized with inorganic matrices. Polyoxometalate anions (POMs) are effective inorganic luminescent centers due to their luminescent properties and structural designability. However, most luminescent POM components are limited to lanthanide-based POMs. In this report, a photoluminescent inorganic-organic hybrid crystal based on a non-lanthanide POM was successfully synthesized as a single crystal. Anderson-type hexamolybdochromate ([CrMo6O18(OH)6]3-, CrMo6) anion exhibiting emission derived from Cr3+ was utilized with n-dodecylammonium ([C12H25NH3]+, C12NH3) surfactant cation to obtain a photoluminescent hybrid crystal. The grown single crystal of C12NH3-CrMo6 comprised a distinct layered structure consisting of inorganic CrMo6 layers and interdigitated C12NH3 layers. In the CrMo6 layers, the CrMo6 anions were associated with water molecules by hydrogen bonding to form a densely packed two-dimensional network. Steady-state and time-resolved photoluminescence spectroscopy revealed that the C12NH3-CrMo6 hybrid crystal exhibited characteristic emission from the CrMo6 anion. Preliminary lasing properties were also observed for C12NH3-CrMo6, which shows the possibility of using the C12NH3-CrMo6 hybrid crystal as an inorganic-organic hybrid laser.

Study on the Curing and Foaming of Surfactant-Modified Geopolymer Gels Based on Ash and Slag Waste from Coal Combustion

This study explores the influence of temperature-time conditions, surfactants, and varied waste compositions on the curing of geopolymer gels, a foam formation with the properties of porous geopolymers. Findings reveal that a 6 h curing period leads to a density of 435 kg/m3 and strength of 0.66 MPa, with notable improvements at 12 h. Comparing 12 to 24 h curing, differences in characteristics remain within 5%, highlighting the 12 h period as more energy-efficient. Sodium stearate-based samples exhibit excellent properties, significantly boosting strength while maintaining overall properties. Microwave curing achieves the lowest density (291 kg/m3) and closely parallels properties of samples cured conventionally for 12 h. However, it leads to complete destruction in sodium stearate-modified gels due to the Dumas reaction, making it unsuitable above 200 °C. Optimal properties emerge from compositions using sodium stearate and oven curing, achieving densities of 334 kg/m3 and strengths of 1.08 MPa (Severodvinsk CHPP-1) and 373 kg/m3 and 1.17 MPa (Novocherkassk SDPP). Although microwave curing allows for high energy efficiency, its high temperature demands necessitate careful material selection. This study offers insight into enhancing geopolymer properties while emphasizing the importance of tailored curing methods for sustainable material development.

Characterization of Nanoprecipitated PET Nanoplastics by 1H NMR and Impact of Residual Ionic Surfactant on Viability of Human Primary Mononuclear Cells and Hemolysis of Erythrocytes

Manufactured nanoplastic particles (NPs) are indispensable for in vitro and in vivo testing and a health risk assessment of this emerging environmental contaminant is needed. The high surface area and inherent hydrophobicity of plastic materials makes the production of NPs devoid of any contaminants very challenging. In this study, we produced nanoprecipitated polyethylene terephthalate (PET) NPs (300 nm hydrodynamic diameter) with an overall yield of 0.76%. The presence of the ionic surfactant sodium dodecyl sulfate (SDS) was characterized by 1H NMR, where the relative ratio of NP/surfactant was monitored on the basis of the chemical shifts characteristic of PET and SDS. For a wide range of surfactant/NP ratios (17:100 to 1.2:100), the measured zeta potential changed from -42.10 to -34.93 mV, but with an NP concentration up to 100 μg/mL, no clear differences were observed in the cellular assays performed in protein-rich media on primary human cells. The remaining impurities contributed to the outcome of the biological assays applied in protein-free buffers, such as human red blood cell hemolysis. The presence of SDS increased the NP-induced hemolysis by 1.5% in protein-rich buffer and by 7.5% in protein-free buffer. As the size, shape, zeta potential, and contaminants of NPs may all be relevant parameters for the biological effects of NPs, the relative quantification of impurities exemplified in our work by the application of 1H NMR for PET NPs and the ionic surfactant SDS could be a valuable auxiliary method in the quality control of manufactured NPs.

Synergistic Stabilization of Nanoemulsion Using Nonionic Surfactants and Salt-Sensitive Cellulose Nanocrystals

Soybean stover is a lignocellulose biomass that is rich in cellulose. In the present study, soybean cellulose nanocrystals (CNCs) were prepared from soybean stover by alkaline treatment, bleaching treatment, acid hydrolysis, dialysis and ultrasonication. The as-prepared soybean CNC was characterized by transmission electron microscopy (TEM), zetasizer and rheometer. The effects of NaCl on the particle size, zeta potential, and viscosity of soybean CNC was studied. Soybean CNC was explored as an emulsion stabilizer for lemongrass-essential-oil-loaded emulsions. Soybean CNCs could stabilize the oil-in-water emulsion against coalescence but not flocculation. The addition of NaCl reduced the creaming index and enhanced the encapsulation efficiency and freeze-thaw stability of the CNC-stabilized emulsion. Salted CNC (i.e., CNC in the presence of NaCl) enhanced the thermodynamic stability (i.e., heating-cooling and freeze-thaw stability) of Tween 80 stabilized emulsion, while unsalted CNC did not. Synergistic effects existed between Tween 80 and salted CNC in stabilizing oil-in-water emulsions. The nanoemulsion stabilized with Tween 80 and salted CNC had a mean particle size of ~70 nm, and it was stable against all thermodynamic stability tests. This is the first study to report the synergistic interaction between salted CNC and small molecular weight surfactants (e.g., Tween 80) to improve the thermodynamic stability of nanoemulsion.

Power-Up for Mucoadhesiveness: Two Generations of Thiolated Surfactants for Enhanced Sticky Nanoemulsions

Nanoemulsions can be tuned toward enhanced gastro-intestinal retention time by incorporating thiolated surfactants into their surface. Tailoring the chemical reactivity of the thiol headgroup has major influence on mucoadhesive features of the nanoemulsion. Two generations of thiolated surfactants were synthetically derived from PEG-40-stearate featuring either a free thiol group or an S-protected thiol group. The surfactants were characterized regarding critical micelle concentration (CMC), hemolytic activity, and cytotoxicity. Subsequently, they were incorporated into nanoemulsions and the resulting nanoemulsions were characterized regarding particle size, polydispersity index (PDI), zeta potential, and time-dependent stability. Afterward, mucosal interactions as well as mucoadhesion on porcine intestinal mucosa were investigated. Successful synthesis of Cysteine-PEG-40-stearate (CYS-PEG-40-stearate) and MNA-Cysteine-PEG-40-stearate (MNA-CYS-PEG-40-stearate) was confirmed by 1H NMR spectroscopy. Both chemical modifications led to slightly elevated CMC values while preserving low cytotoxicity and hemotoxicity. Incorporation into nanoemulsions had minor influence on overall physical particle characteristics, while interactions with mucus and mucoadhesiveness of the nanoemulsions were drastically improved resulting in the rank order PEG-40-stearate < CYS-PEG-40-stearate < MNA-CYS-PEG-40-stearate. Accordingly, thiolated surfactants, especially S-protected derivatives, are versatile tools to generate highly mucoadhesive nanoemulsions.

Colloidal gas aphrons for biotechnology applications: a mini review

Colloidal gas aphrons (CGAs) are highly stable, spherical, micrometer-sized bubbles encapsulated by surfactant multilayers. They have several intriguing properties, including: high stability, large interfacial area, and the ability to maintain the same charge as their parent molecules. The physical properties of CGAs make them ideal for biotechnological applications such as the recovery of a variety of: biomolecules, particularly proteins, yeast, enzymes, and microalgae. In this review, the bio-application of CGAs for the recovery of natural components is presented, as well as: experimental results, technical challenges, and critical research directions for the future. Experimental results from the literature showed that the recovery of biomolecules was mainly determined by electrostatic or hydrophobic interactions between polyphenols and proteins (lysozyme, β-casein, β-lactoglobulin, etc.), yeast, biological molecules (gallic acid and norbixin), and microalgae with CGAs. Knowledge transfer is essential for commercializing CGA-based bio-product recovery, which will be recognized as a viable technology in the future.

Drug Release from Surfactant-Containing Amorphous Solid Dispersions: Mechanism and Role of Surfactant in Release Enhancement

PURPOSE

To understand how surfactants affect drug release from ternary amorphous solid dispersions (ASDs), and to investigate different mechanisms of release enhancement.

METHODS

Ternary ASDs containing ritonavir (RTV), polyvinylpyrrolidone/vinyl acetate (PVPVA) and a surfactant (sodium dodecyl sulfate (SDS), Tween 80, Span 20 or Span 85) were prepared with rotary evaporation. Release profiles of ternary ASDs were measured with surface normalized dissolution. Phase separation morphologies of ASD compacts during hydration/dissolution were examined in real-time with a newly developed confocal fluorescence microscopy method. The water ingress rate of different formulations was measured with dynamic vapor sorption. Microscopy was employed to check for matrix crystallization during release studies.

RESULTS

All surfactants improved drug release at 30% DL, while only SDS and Tween 80 improved drug release at higher DLs, although SDS promoted matrix crystallization. The dissolution rate of neat polymer increased when SDS and Tween 80 were present. The water ingress rate also increased in the presence of all surfactants. Surfactant-incorporation affected both the kinetic and thermodynamics factors governing phase separation of RTV-PVPVA-water system, modifying the phase morphology during ASD dissolution. Importantly, SDS increased the miscibility of RTV-PVPVA-water system, whereas other surfactants mainly affected the phase separation kinetics/drug-rich barrier persistence.

CONCLUSION

Incorporation of surfactants enhanced drug release from RTV-PVPVA ASDs compared to the binary system. Increased drug-polymer-water miscibility and disruption of the drug-rich barrier at the gel-solvent interface via plasticization are highlighted as two key mechanisms underlying surfactant impacts based on direct visualization of the phase separation process upon hydration and release.

Dissolvable shower gel tablets with enhanced skin benefits

OBJECTIVE

The excessive use of plastic packaging, even though it is possible to recycle it, is one of the main causes of global warming. In this study, dissolvable shower gel tablets for multiple uses have been developed in order to reduce the use of fresh plastic packaging.

METHODS

The appropriate ratio of two surfactants, cocoyl glutamic acid (CGA) and sodium coco sulphate (SCS), was optimized using design of experiments. Additionally, skin hydration of the emollient either omega oil or glycerine was taken into account when determining its concentration. After that, powdered shower gel formulations were made and tested for their properties, including cleaning power, and foamability. On 30 human volunteers, the effects of reconstituted shower gel on skin redness, cleaning effectiveness and overall satisfaction were evaluated.

RESULTS

The study found that, when cleaning power and foam height were taken into account, the proper surfactant ratio was 7.5:0 (SCS:CGA). The 5% glycerine shower gel formula demonstrated significantly greater skin hydration than other formulas. The in vivo study's findings demonstrated that there was no statistically significant difference between selected formulas (5% glycerine and 2.5% omega oil) in terms of cleaning ability. Comparing both formulas to the control, neither showed any skin redness. Additionally, it was discovered that the developed products were much more effective at cleaning and easier to use when washing for the volunteers than regular liquid soap. Overall satisfaction and the moisturizing feel were not significantly different among all products.

CONCLUSION

The formula with 7.5% SCS and 5% glycerine is said to be the best one for both cleaning ability and moisturizing effect. These findings suggest that dissolvable shower gel tablets with enhanced skin benefits could offer a promising innovation in the personal care industry.