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1.
J Chem Phys ; 161(1)2024 Jul 07.
Article in English | MEDLINE | ID: mdl-38949588

ABSTRACT

Investigating the influence of the ambient chemical environment on molecular behaviors in liposomes is crucial for understanding and manipulating cellular vitality as well as the capabilities of lipid drug carriers in various environments. Here, we designed and synthesized a second harmonic generation (SHG) and fluorescence probe molecule called Pyr-Py+-N+ (PPN), which possesses membrane-targeting capability. We employed PPN to investigate the response of lipid vesicles composed of cardiolipin to the presence of exogenous salt. The kinetic behaviors, including the adsorption and embedding of PPN on the surface of small unilamellar vesicles (SUVs) composed of cardiolipin, were analyzed. The response of the SUVs to the addition of NaCl was also monitored. A rapid decrease in vesicle size can be evidenced through the rapid drop in SHG emission originating from PPN located on the vesicle surface.


Subject(s)
Cardiolipins , Fluorescent Dyes , Unilamellar Liposomes , Cardiolipins/chemistry , Fluorescent Dyes/chemistry , Unilamellar Liposomes/chemistry , Surface Properties , Liposomes/chemistry , Sodium Chloride/chemistry , Surface-Active Agents/chemistry , Molecular Structure
2.
Wound Manag Prev ; 70(2)2024 Jun.
Article in English | MEDLINE | ID: mdl-38959343

ABSTRACT

BACKGROUND: CSG dressing is water-soluble and helps to hydrate the wound, control exudate, and provide gentle debridement by virtue of a high concentration of surfactant micelles. The primary objective of this retrospective case series is to report on the feasibility of CSG use in pediatric wounds and its mechanism of action. The secondary aim was to measure pain during application and removal of CSG. METHODS: Eight pediatric patients ranging in age from newborn to a few months old with wounds requiring medical intervention were treated with CSG. The CSG dressing was applied twice daily at initiation of treatment in some patients, but mostly once daily. NIPS was utilized for pain measurements. RESULTS: Near-complete healing of wounds was observed by the end of treatment duration, which was only a few days. The calm temperament of these patients during dressing changes and objective NIPS suggested minimal to no pain. None of the patients experienced any adverse events related to the use of this dressing. CONCLUSION: The CSG dressing could be the dressing of choice in this population to enhance debridement and maintain moist healing and support granulation, either proactively or if other treatments fail.


Subject(s)
Bandages , Surface-Active Agents , Wound Healing , Humans , Wound Healing/drug effects , Infant , Retrospective Studies , Male , Female , Bandages/standards , Bandages/statistics & numerical data , Surface-Active Agents/therapeutic use , Surface-Active Agents/pharmacology , Infant, Newborn , Gels/therapeutic use , Wounds and Injuries/therapy , Wounds and Injuries/drug therapy
3.
Sci Rep ; 14(1): 15106, 2024 07 02.
Article in English | MEDLINE | ID: mdl-38956156

ABSTRACT

We applied computing-as-a-service to the unattended system-agnostic miscibility prediction of the pharmaceutical surfactants, Vitamin E TPGS and Tween 80, with Copovidone VA64 polymer at temperature relevant for the pharmaceutical hot melt extrusion process. The computations were performed in lieu of running exhaustive hot melt extrusion experiments to identify surfactant-polymer miscibility limits. The computing scheme involved a massively parallelized architecture for molecular dynamics and free energy perturbation from which binodal, spinodal, and mechanical mixture critical points were detected on molar Gibbs free energy profiles at 180 °C. We established tight agreement between the computed stability (miscibility) limits of 9.0 and 10.0 wt% vs. the experimental 7 and 9 wt% for the Vitamin E TPGS and Tween 80 systems, respectively, and identified different destabilizing mechanisms applicable to each system. This paradigm supports that computational stability prediction may serve as a physically meaningful, resource-efficient, and operationally sensible digital twin to experimental screening tests of pharmaceutical systems. This approach is also relevant to amorphous solid dispersion drug delivery systems, as it can identify critical stability points of active pharmaceutical ingredient/excipient mixtures.


Subject(s)
Excipients , Polysorbates , Excipients/chemistry , Polysorbates/chemistry , Vitamin E/chemistry , Surface-Active Agents/chemistry , Pyrrolidines/chemistry , Molecular Dynamics Simulation , Thermodynamics , Hot Melt Extrusion Technology/methods , Vinyl Compounds
4.
Mol Pharm ; 21(7): 3540-3552, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38900044

ABSTRACT

Molecular dynamics (MD) simulations of linear amylose fragments containing 10 to 40 glucose units were used to study the complexation of the prototypical compound, 3-pentadecylphenol (PDP)─a natural product with surfactant-like properties─in aqueous solution. The amylose-PDP binding leverages mainly hydrophobic interactions together with excluded volume effects. It was found that while the most stable complexes contained PDP inside the helical structure of the amylose in the expected guest-host (inclusion) complexation manner, at higher temperatures, the commonly observed PDP-amylose complexes often involved more nonspecific interactions than inclusion complexation. In the case where a stoichiometric excess of PDP was added to the simulation box, self-aggregation of the small molecule precluded its ability to enter the internal helical part of the oligosaccharide, and as a result, inclusion complexation became ineffective. MD simulation trajectories were analyzed preliminarily using cluster analysis (CA), followed by more rigorous solvent accessible surface area (SASA) determination over the temperature range spanning from 277 to 433 K. It was found that using the SASA of PDP corrected for its intrinsic conformational changes, together with a generic hidden Markov model (HMM), an adequate quantification of the different types of PDP-amylose aggregates was obtained to allow further analysis. The enthalpy change associated with the guest-host binding equilibrium constant (Kgh) in aqueous solution was estimated to be -75 kJ/mol, which is about twice as high as one might expect based on experimentally measured values of similar complexes in the solid state where the (unsolvated) helical structure of amylose remains rigid. On the other hand, the nonspecific binding (Kns) enthalpy change associated with PDP-amylose interactions in the same solution environment was found to be about half of the inclusion complexation value.


Subject(s)
Amylose , Molecular Dynamics Simulation , Phenols , Amylose/chemistry , Phenols/chemistry , Water/chemistry , Hydrophobic and Hydrophilic Interactions , Surface-Active Agents/chemistry , Temperature , Thermodynamics
5.
J Phys Chem Lett ; 15(25): 6611-6620, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38888261

ABSTRACT

Amphiphilic peptides show great potential for exfoliating graphite and functionalizing graphene. However, the variety of amino acids complicates our understanding of the underlying mechanisms. In this study, we designed four peptides (C6W1, C6W2, C6W4, and C6W6) with different amounts of aromatic tryptophan amino acids and two additional peptides (C6F4 and C6Y4) by substituting tryptophan with aromatic phenylalanine or tyrosine. This allowed us to investigate the processes and mechanisms of graphite exfoliation and graphene functionalization. Using experimental and computational methods, we discovered that peptides containing tryptophan demonstrated higher exfoliation efficiency and increased tryptophan content further improved this efficiency, resulting in more peptide-functionalized graphene layers. Significantly, the primary driving force for the surface-assisted assembly of peptides on graphite is the π-π stacking interaction between the aromatic ring contributed by aromatic amino acids and the hexagonal rings of the graphite surface. This interaction leads to a layer-by-layer exfoliation mechanism. Our research offers valuable insights into peptide design strategies for one-step graphite exfoliation and graphene functionalization in aqueous environments.


Subject(s)
Amino Acids, Aromatic , Graphite , Peptides , Surface Properties , Graphite/chemistry , Peptides/chemistry , Amino Acids, Aromatic/chemistry , Tryptophan/chemistry , Surface-Active Agents/chemistry
6.
Sci Rep ; 14(1): 13201, 2024 06 08.
Article in English | MEDLINE | ID: mdl-38851845

ABSTRACT

Sugar esters display surface-active properties, wetting, emulsifying, and other physicochemical phenomena following their amphipathic nature and recognize distinct biological activity. The development of nutritional pharmaceuticals and other applications remains of great interest. Herein, three novel homologous series of several N-mono-fatty acyl amino acid glucosyl esters were synthesized, and their physicochemical properties and biological activities were evaluated. The design and preparation of these esters were chemically performed via the reaction of glucose with different fatty acyl amino acids as renewable starting materials, with the suggestion that they would acquire functional characteristics superior and competitive to certain conventional surfactants. The synthesized products are characterized using FTIR, 1H-NMR, and 13C-NMR spectroscopy. Further, their physicochemical properties, such as HLB, CMC, Γmax, γCMC, and Amin, were determined. Additionally, their antimicrobial and anticancer efficiency were assessed. The results indicate that the esters' molecular structure, including the acyl chain length and the type of amino acid, significantly influences their properties. The measured HLB ranged from 8.84 to 12.27, suggesting their use as oil/water emulsifiers, wetting, and cleansing agents. All esters demonstrate promising surface-active characteristics, with moderate to high foam production with good stability. Notably, compounds 6-O-(N-dodecanoyl, tetradecanoyl cysteine)-glucopyranose (34, 35), respectively and 6-O-(N-12-hydroxy-9-octadecenoyl cysteine)-glucopyranose (38) display superior foamability. Wetting efficiency increased with decreasing the chain length of the acyl group. The storage results reveal that increasing the fatty acyl hydrophobe length enhances the derived emulsion's stability for up to 63 days. Particularly, including cysteine in these glucosyl esters improves wetting, foaming, and emulsifying potentialities. Furthermore, the esters exhibit antibacterial activity against several tested Gram-positive and Gram-negative bacteria and fungi. On the other hand, they show significant antiproliferative effects on some liver tumor cell lines. For instance, compounds 6-O-(N-12-hydroxy-9-octadecenoylglycine)-glucopyranose (28), 6-O-(N-dodecanoyl, hexadecanoyl, 9-octadecenoyl and 12-hydroxy-9-octadecenoylvaline)- glucopyranose (29, 31, 32 and 33), respectively in addition to the dodecanoyl, hexadecanoyl, 9-octadecenoyl and 12-hydroxy-9-octadecenoyl cysteine glucopyranose (34, 36, 37 and 38), respectively significantly inhibit the examined cancer cells.


Subject(s)
Anti-Infective Agents , Antineoplastic Agents , Surface-Active Agents , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Surface-Active Agents/chemistry , Surface-Active Agents/chemical synthesis , Surface-Active Agents/pharmacology , Humans , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/chemical synthesis , Structure-Activity Relationship , Microbial Sensitivity Tests , Esters/chemistry , Esters/pharmacology , Esters/chemical synthesis , Cell Line, Tumor , Amino Acids/chemistry
7.
Chem Commun (Camb) ; 60(52): 6683-6686, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38860957

ABSTRACT

This study introduces boronic ester-based ROS-responsive amphiphilic copolymers for antioxidant drug delivery. Tuning the hydrophobic/hydrophilic balance optimized the size, curcumin encapsulation, ROS-triggered release, cellular uptake, and intracellular ROS scavenging. The lead P1b formulation self-assembled into stable 10 nm micelles enabling rapid ROS-triggered curcumin release and preferential cellular internalization. P1b eliminated over 90% of pathogenic intracellular ROS within 10 minutes, demonstrating a rapid antioxidant therapy.


Subject(s)
Boronic Acids , Curcumin , Esters , Polymers , Reactive Oxygen Species , Reactive Oxygen Species/metabolism , Esters/chemistry , Esters/pharmacology , Humans , Boronic Acids/chemistry , Curcumin/chemistry , Curcumin/pharmacology , Polymers/chemistry , Micelles , Hydrophobic and Hydrophilic Interactions , Antioxidants/chemistry , Antioxidants/pharmacology , Drug Carriers/chemistry , Surface-Active Agents/chemistry , Surface-Active Agents/chemical synthesis , Drug Liberation , Drug Delivery Systems , Cell Survival/drug effects , Molecular Structure
8.
J Hazard Mater ; 475: 134915, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38878443

ABSTRACT

Various exogenous contaminants typically coexist in waste activated sludge (WAS), and the long-term impacts of these co-occurring contaminants on WAS anaerobic fermentation and associated mechanisms remain largely unknown. This study reveals that the co-occurrence of surfactants and nanoparticles (NPs, i.e., Fe2O3 and CeO2, frequently detected in sludge) exhibited time-dependent impacts on the volatile fatty acids (VFAs) biosynthesis. Surfactants triggered WAS decomposition and enhanced NPs dispersion, leading to increased exposure of functional anaerobes to NPs toxicity, negatively affecting them. Consequently, key fermentation processes, acidogenic bacterial abundance, and metabolic functions were inhibited in co-occurrence reactors compared to those containing only surfactants in the early stage (before 56 d). Surprisingly, the fermentation systems containing surfactants collapsed subsequently, with VFAs yield at 72 d decreasing by 48.59-71.27 % compared to 56 d. The keystone microbes (i.e., Acidobacteria (16 d) vs Patescibacteria (56 d)) were reshaped, and metabolic traits (i.e., proB involved in intracellular metabolism) were downregulated by 0.05-78.02 % due to reduced microbial adaptive capacity (i.e., quorum sensing (QS)). Partial least squares path modeling (PLS-PM) analysis suggests that the microbial community was the predominant factor influencing VFAs generation. This study provides new insights into the long-term effects of co-contaminants on the biological treatment of WAS.


Subject(s)
Cerium , Fatty Acids, Volatile , Fermentation , Sewage , Surface-Active Agents , Sewage/microbiology , Fatty Acids, Volatile/metabolism , Surface-Active Agents/metabolism , Surface-Active Agents/chemistry , Cerium/metabolism , Cerium/chemistry , Bioreactors , Ferric Compounds/chemistry , Bacteria/metabolism , Bacteria/drug effects , Nanoparticles/chemistry
9.
World J Microbiol Biotechnol ; 40(8): 253, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38914906

ABSTRACT

Liamocins, a group of high-density glycolipids, are only produced by certain strains of the yeast-like fungi in the genus Aureobasidium. Until now, few studies have focused on the surfactant properties of liamocins produced from the highly diverse tropical strains of Aureobasidium. Therefore, the aims of this research were to screen the liamocin production from tropical strains of Aureobasidium spp. and to characterize their surfactant properties. A total of 41 strains of Thai Aureobasidium spp. were screened for their ability to produce liamocins, and the products were detected using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and thin-layer chromatography. Of those strains, 30 strains of Aureobasidium spp. tested were found to produce liamocins with yields ranging from 0.53 to 10.60 g/l. The nature of all crude liamocins was heterogeneous, with different compositions and ratios depending on the yeast strain. These liamocins exhibited relatively high emulsifying activity against vegetable oils tested, with an emulsification index of around 40-50%; the emulsion stability of some liamocins was up to 30 days. The obtained critical micelle concentration values were varied, with those ​​of liamocins produced from A. pullulans, A. melanogenum and A. thailandense falling in ranges from 7.70 to 119.78, 10.73 to > 1,000, and 68.56 to > 1,000 mg/l, respectively. The emulsification activity of liamocins was higher than that of the analytical grade rhamnolipids. These compounds showed strong surface tension reduction in a sodium chloride concentration range of 2-12% (w/v), pH values between 3 and 7, and temperatures between 4 and 121 °C. This is the first report of liamocins produced by A. thailandense.


Subject(s)
Aureobasidium , Glycolipids , Glycolipids/metabolism , Glycolipids/biosynthesis , Glycolipids/chemistry , Aureobasidium/metabolism , Surface-Active Agents/metabolism , Surface-Active Agents/pharmacology , Surface-Active Agents/chemistry , Thailand , Chromatography, Thin Layer , Plant Oils/metabolism , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Emulsifying Agents/metabolism , Emulsifying Agents/chemistry , Emulsions
10.
Methods Mol Biol ; 2817: 85-96, 2024.
Article in English | MEDLINE | ID: mdl-38907149

ABSTRACT

With advanced mass spectrometry (MS)-based proteomics, genome-scale proteome coverage can be achieved from bulk cells. However, such bulk measurement obscures cell-to-cell heterogeneity, precluding proteome profiling of single cells and small numbers of cells of interest. To address this issue, in the recent 5 years, there has been a surge of small sample preparation methods developed for robust and effective collection and processing of single cells and small numbers of cells for in-depth MS-based proteome profiling. Based on their broad accessibility, they can be categorized into two types: methods based on specific devices and those based on standard PCR tubes or multi-well plates. In this chapter, we describe the detailed protocol of our recently developed, easily adoptable, Surfactant-assisted One-Pot (SOP) sample preparation coupled with MS method termed SOP-MS for label-free single-cell and nanoscale proteomics. SOP-MS capitalizes on the combination of an MS-compatible surfactant, n-dodecyl-ß-D-maltoside (DDM), and standard low-bind PCR tube or multi-well plate for "all-in-one" one-pot sample preparation without sample transfer. With its robust and convenient features, SOP-MS can be readily implemented in any MS laboratory for single-cell and nanoscale proteomics. With further improvements in MS detection sensitivity and sample throughput, we believe that SOP-MS could open an avenue for single-cell proteomics with broad applicability in biological and biomedical research.


Subject(s)
Proteomics , Single-Cell Analysis , Surface-Active Agents , Proteomics/methods , Surface-Active Agents/chemistry , Single-Cell Analysis/methods , Humans , Mass Spectrometry/methods , Proteome/analysis , Nanotechnology/methods , Glucosides
11.
ACS Appl Mater Interfaces ; 16(26): 34409-34418, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38889207

ABSTRACT

Nanosizing drug crystals has emerged as a successful approach to enabling oral bioavailability, as increasing drug crystal surface area improves dissolution kinetics and effective solubility. Recently, bottom-up methods have been developed to directly assemble nanosized crystals by leveraging polymer and surfactant excipients during crystallization to control crystal size, morphology, and structure. However, while significant research has investigated how polymers and other single additives inhibit or promote crystallization in pharmaceutical systems, there is little work studying the mechanistic interactions of multiple excipients on drug crystal structure and the extent of crystallinity, which can influence formulation performance. This study explores how the structure and crystallinity of a model hydrophobic drug crystal, fenofibrate, change as a result of competitive interfacial chemisorption between common nonionic surfactants (polysorbate 80 and sorbitan monooleate) and a surface-active polymer excipient (methylcellulose). Classical molecular dynamics simulations highlight how key intermolecular interactions, including surfactant-polymer complexation and surfactant screening of the crystal surface, modify the resulting crystal structure. In parallel, experiments generating drug nanocrystals in hydrogel thin films validate that drug crystallinity increases with an increasing weight fraction of surfactant. Simulation results reveal a connection between accelerated dynamics in the bulk crystal and the experimentally measured extent of crystallinity. To our knowledge, these are the first simulations that directly characterize structural changes in a drug crystal as a result of excipient surface composition and relate the experimental extent of crystallinity to structural changes in the molecular crystal. Our approach provides a mechanistic understanding of crystallinity in nanocrystallization, which can expand the range of orally deliverable small molecule therapies.


Subject(s)
Crystallization , Fenofibrate , Molecular Dynamics Simulation , Nanoparticles , Surface-Active Agents , Surface-Active Agents/chemistry , Nanoparticles/chemistry , Fenofibrate/chemistry , Hexoses/chemistry , Polysorbates/chemistry , Methylcellulose/chemistry , Surface Properties , Hydrophobic and Hydrophilic Interactions , Polymers/chemistry
12.
J Oleo Sci ; 73(7): 921-941, 2024.
Article in English | MEDLINE | ID: mdl-38945922

ABSTRACT

This comprehensive review offers a chemical analysis of cutting fluids, delving into both their formulation and deformulation processes. The study covers a wide spectrum of cutting fluid formulations, ranging from simple compositions predominantly comprising oils, whether mineral or vegetable, to emulsions. The latter involves the integration of surfactants, encompassing both nonionic and anionic types, along with a diverse array of additives. Concerning oils, the current trend leans towards the use of vegetable oils instead of mineral oils for environmental reasons. As vegetable oils are more prone to oxidation, chemical alterations, the addition of antioxidant may be necessary. The chemical aspects of the different compounds are scrutinized, in order to understand the role of each component and its impact on the fluid's lubricating, cooling, anti-wear, and anti-corrosion properties. Furthermore, the review explores the deformulation methodologies employed to dissect cutting fluids. This process involves a two-step approach: separating the aqueous and organic phases of the emulsions by physical or chemical treatments, and subsequently conducting a detailed analysis of each to identify the compounds. Several analytical techniques, including spectrometric or chromatographic, can be employed simultaneously to reveal the chemical structures of samples. This review aims to contribute to the improvement of waste treatment stemming from cutting fluids. By gathering extensive information about the formulation, deformulation, and chemistry of the ingredients, there is a potential to enhance the waste management and disposal effectively.


Subject(s)
Emulsions , Surface-Active Agents , Emulsions/chemistry , Surface-Active Agents/chemistry , Plant Oils/chemistry , Mineral Oil/chemistry , Antioxidants/chemistry , Antioxidants/analysis , Oxidation-Reduction , Lubrication , Lubricants/chemistry , Chemical Phenomena
13.
J Oleo Sci ; 73(7): 953-961, 2024.
Article in English | MEDLINE | ID: mdl-38945924

ABSTRACT

Handwashing represents an important personal hygiene measure for preventing infection. Herein, we report the persistence of antibacterial and antiviral effects after handwashing with fatty acid salt-based hand soap. To this end, we developed a new in vitro test method to measure persistence, utilizing coacervation formed by anionic surfactants and cationic polymers to retain highly effective soap components against each bacterium and virus on the skin. Coacervation with fatty acid salts and poly diallyldimethylammonium chloride (PDADMAC) as a cationic polymer allowed the persistence of antibacterial and antiviral effects against E. coli, S. aureus, and influenza virus even 4 h after handwashing. Furthermore, we confirmed an increase in the number of residual components effective against each bacterium and virus on the skin. In summary, the current findings describe an effective approach for enhancing the protective effects of handwashing.


Subject(s)
Anti-Bacterial Agents , Antiviral Agents , Escherichia coli , Hand Disinfection , Polyethylenes , Quaternary Ammonium Compounds , Skin , Soaps , Staphylococcus aureus , Surface-Active Agents , Soaps/pharmacology , Escherichia coli/drug effects , Hand Disinfection/methods , Quaternary Ammonium Compounds/pharmacology , Anti-Bacterial Agents/pharmacology , Staphylococcus aureus/drug effects , Antiviral Agents/pharmacology , Skin/drug effects , Skin/microbiology , Surface-Active Agents/pharmacology , Humans , Fatty Acids/pharmacology , Fatty Acids/analysis , Time Factors , Orthomyxoviridae/drug effects
14.
J Colloid Interface Sci ; 672: 244-255, 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-38838632

ABSTRACT

HYPOTHESIS: Nonionic surfactants can counter the deleterious effect that anionic surfactants have on proteins, where the folded states are retrieved from a previously unfolded state. However, further studies are required to refine our understanding of the underlying mechanism of the refolding process. While interactions between nonionic surfactants and tightly folded proteins are not anticipated, we hypothesized that intermediate stages of surfactant-induced unfolding could define new interaction mechanisms by which nonionic surfactants can further alter protein conformation. EXPERIMENTS: In this work, the behavior of three model proteins (human growth hormone, bovine serum albumin, and ß-lactoglobulin) was investigated in the presence of the anionic surfactant sodium dodecylsulfate, the nonionic surfactant ß-dodecylmaltoside, and mixtures of both surfactants. The transitions occurring to the proteins were determined using intrinsic fluorescence spectroscopy and far-UV circular dichroism. Based on these results, we developed a detailed interaction model for human growth hormone. Using nuclear magnetic resonance and contrast-variation small-angle neutron scattering, we studied the amino acid environment and the conformational state of the protein. FINDINGS: The results demonstrate the key role of surfactant cooperation in defining the conformational state of the proteins, which can shift away or toward the folded state depending on the nonionic-to-ionic surfactant ratio. Dodecylmaltoside, initially a non-interacting surfactant, can unexpectedly associate with sodium dodecylsulfate-unfolded proteins to further impact their conformation at low nonionic-to-ionic surfactant ratio. When this ratio increases, the protein begins to retrieve the folded state. However, the native conformation cannot be fully recovered due to remnant surfactant molecules still adsorbed to the protein. This study demonstrates that the conformational landscape of the protein depends on a delicate interplay between the surfactants, ultimately controlled by the ratio between them, resulting in unpredictable changes in the protein conformation.


Subject(s)
Lactoglobulins , Protein Unfolding , Serum Albumin, Bovine , Sodium Dodecyl Sulfate , Surface-Active Agents , Surface-Active Agents/chemistry , Humans , Lactoglobulins/chemistry , Protein Unfolding/drug effects , Sodium Dodecyl Sulfate/chemistry , Cattle , Serum Albumin, Bovine/chemistry , Animals , Human Growth Hormone/chemistry , Anions/chemistry , Protein Refolding/drug effects , Protein Conformation , Glucosides
15.
J Colloid Interface Sci ; 672: 209-223, 2024 Oct 15.
Article in English | MEDLINE | ID: mdl-38838629

ABSTRACT

Multidrug resistance (MDR) is a rising threat to global health because the number of essential antibiotics used for treating MDR infections is increasingly compromised. In this work we report a group of new amphiphilic peptides (AMPs) derived from the well-studied G3 (G(IIKK)3I-NH2) to fight infections from Gram-positive bacteria including susceptible Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA), focusing on membrane interactions. Time-dependent killing experiments revealed that substitutions of II by WW (GWK), II by FF (GFK) and KK by RR (GIR) resulted in improved bactericidal efficiencies compared to G3 (GIK) on both S. aureus and MRSA, with the order of GWK > GIR > GFK > GIK. Electronic microscopy imaging revealed structural disruptions of AMP binding to bacterial cell walls. Fluorescence assays including AMP binding to anionic lipoteichoic acids (LTA) in cell-free and cell systems indicated concentration and time-dependent membrane destabilization associated with bacterial killing. Furthermore, AMP's binding to anionic plasma membrane via similar fluorescence assays revealed a different extent of membrane depolarization and leakage. These observations were supported by the penetration of AMPs into the LTA barrier and the subsequent structural compromise to the cytoplasmic membrane as revealed from SANS (small angle neutron scattering). Both experiments and molecular dynamics (MD) simulations revealed that GWK and GIR could make the membrane more rigid but less effective in diffusive efficiency than GIK and GFK through forming intramembrane peptide nanoaggregates associated with hydrophobic mismatch and formation of fluidic and rigid patches. The reported peptide-aggregate-induced phase-separation emerged as a crucial factor in accelerated membrane disintegration and fast bacterial killing. This work has demonstrated the importance of membrane interactions to the development of more effective AMPs and the relevance of the approaches as reported in assisting this area of research.


Subject(s)
Anti-Bacterial Agents , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Methicillin-Resistant Staphylococcus aureus/drug effects , Staphylococcus aureus/drug effects , Antimicrobial Cationic Peptides/chemistry , Antimicrobial Cationic Peptides/pharmacology , Cations/chemistry , Surface-Active Agents/chemistry , Surface-Active Agents/pharmacology , Molecular Dynamics Simulation
16.
Bull Exp Biol Med ; 176(6): 709-715, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38888647

ABSTRACT

The review presents the results of the blood substitute development based on perfluororganic compounds (PFC). The limitations of PFC due to which their further development was suspended are described. The presented data allows us to imagine a possible way to create optimal drugs based on PFC. Chemically inactive perfluorocomponents should be used - perfluorinated hydrocarbons and tertiary perfluorinated amines. However, in order to emulsify and stabilize the emulsion, other types of effective and chemically indifferent surfactants that do not interact with oxygen and other components of the drug are needed.


Subject(s)
Blood Substitutes , Fluorocarbons , Fluorocarbons/chemistry , Humans , Surface-Active Agents/chemistry , Surface-Active Agents/pharmacology , Emulsions/chemistry , Oxygen/chemistry , Animals
17.
Environ Sci Pollut Res Int ; 31(30): 43262-43280, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38902440

ABSTRACT

This study investigated the elaboration of novel porous absorbent granules by mixing powdered hydroxyapatite, metakaolin, sodium metasilicate, polyethylene glycol, and sodium dodecyl sulfate (SDS), an anionic surfactant. The effect of sodium dodecyl sulfate (SDS) was then studied by introducing it as a powder to the powdered mixture or dissolved into the granulation fluid. Characterization of the granules indicated that the incorporation of SDS dissolved in the granulation fluid into the G-PEG granules improved their specific surface area (97.9 m2/g) and porosity, resulting in a synergistic increase in the adsorption of crystal violet and methylene blue dyes compared to G-PEG granules and hydroxyapatite or metakaolin geopolymer alone. Moreover, the granules exhibited satisfactory compressive strength of 0.81 MPa, making them suitable for large-scale adsorption columns. Finally, the regeneratiοn prοcess οf the granules was modeled and optimized by using surface response methodology based on Box-Behnken design. The granules cοuld be regenerated fοr eight cycles under οptimum cοnditiοns οf acetic acid cοncentratiοn οf 0.72 mοl/L, a temperature οf 323 K, and a cοntact time οf 173.22 min, withοut a significant lοss in the adsοrptiοn capacity οr degradatiοn οf the granules. These results suggest that the pοrοus granules prepared in this study have pοtential tο be used in industrial wastewater treatment.


Subject(s)
Sodium Dodecyl Sulfate , Surface-Active Agents , Surface-Active Agents/chemistry , Sodium Dodecyl Sulfate/chemistry , Adsorption , Durapatite/chemistry
18.
Mol Pharm ; 21(7): 3674-3683, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38838194

ABSTRACT

The efficacy of nanostructured lipid carriers (NLC) for drug delivery strongly depends on their stability and cell uptake. Both properties are governed by their compositions and internal structure. To test the effect of the lipid composition of NLC on cell uptake and stability, three kinds of liquid lipids with different degrees of unsaturation are employed. After ensuring homogeneous size distributions, the thermodynamic characteristics, stability, and mixing properties of NLC are characterized. Then the rates and predominant pathways of cell uptake are determined. Although the same surfactant is used in all cases, different uptake rates are observed. This finding contradicts the view that the surface properties of NLC are dominated by the surfactant. Instead, the uptake rates are explained by the structure of the nanocarrier. Depending on the mixing properties, some liquid lipids remain inside the nanocarrier, while other liquid lipids are present on the surface. Nanocarriers with liquid lipids on the surface are taken up more readily by the cells. This shows that the engineering of efficient lipid nanocarriers requires a delicate balance of interactions between all components of the nanocarrier on the molecular level.


Subject(s)
Drug Carriers , Drug Delivery Systems , Lipids , Nanostructures , Lipids/chemistry , Drug Carriers/chemistry , Nanostructures/chemistry , Drug Delivery Systems/methods , Humans , Surface-Active Agents/chemistry , Nanoparticles/chemistry , Thermodynamics , Particle Size , Surface Properties
19.
Environ Sci Pollut Res Int ; 31(30): 43080-43095, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38888824

ABSTRACT

Foaming agents as a combination of several components are usually used as soil conditioning during earth pressure balance shield (EPBS) tunnelling. These residues in waste EPBS muck lead to a series of new challenges for in-situ recycling, i.e., foams overflow flocculation tank. This study investigates the effects of residual foaming agent components and defoamers on defoaming-flocculation-filterpress characteristics of EPBS muck using an improved flocculation and filterpress system. Residual foam height (Hf), defoaming ratio (DFR), antifoaming ratio (AFR), total suspended substance (TSS), turbidity, moisture content (MC), and zeta potential (ZP) were selected as characterization indices. The microstructure of filterpress cakes was analyzed using a scanning electron microscope. Results demonstrate that an enhancement within 0.0-1.0wt.% for sodium fatty alcohol polyoxyethylene ether sulfate (AES) and alpha olefin sulfonate (AOS) significantly reduces DFR and AFR. The MC and ZP decline, while the Hf and turbidity enhance. The combinations of nonionic surfactants alkyl polyglycoside (APG) and fatty alcohol-polyoxyethylene ether (AEO) in a concentration range of 0.0-1.0wt.% with 0.2wt.% AES causes the Hf, DFR, AFR, turbidity, and ZP to exhibit absolutely different variations. The MC with the growth in both APG and AEO presents a trend of first decreasing and then increasing. By increasing foam stabilizers sodium carboxymethyl cellulose (CMC) and guar gum (GG) within 0.02-0.10wt.%, the AFR, TSS, and ZP enhance in varying degrees, while the Hf, DFR, and MC gradually reduce. With the increase of defoamers hydroxyl silicone oil-glycerol polyoxypropylene ether (H-G) and dimethyl silicone oil-glycerol polyoxypropylene ether (D-G) within 0.002-0.010wt.%, the DFR and AFR are significantly improved, while the TSS, turbidity, MC, and ZP display varying degrees of reduction. Moreover, defoaming-flocculation-filterpress mechanisms of EPBS muck are explored to provide a useful reference for actual in-situ recycling projects.


Subject(s)
Flocculation , Pressure , Soil/chemistry , Surface-Active Agents/chemistry
20.
Int J Biol Macromol ; 273(Pt 1): 132966, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38851620

ABSTRACT

The multifunctionality of advanced laundry detergents primarily relies on the inclusion of functional solid particles, such as pearlescent powder, enzymes, and perfume microcapsules. However, the high-content surfactants in these detergents can render most existing suspending rheology modifiers ineffective, making it challenging to achieve uniform suspension of these functional particles. This compromises the overall functionality of laundry products. To address this, we have developed a binary rheology modifier comprising cellulose microgel and HPMC (hydroxypropyl methylcellulose), acting as the "island" and "chain," respectively. Together, they form an interconnected dynamic network that effectively "encapsulates" the functional particles. Furthermore, the cellulose microgel/HPMC rheology modifier demonstrates versatility, proving effective with various surfactants. Despite its potential, the suspension mechanism of cellulose microgel/HPMC remains elusive. Therefore, we conducted a comprehensive investigation, fabricating cellulose microgels with varying nanofabrication degrees and surface charges through TEMPO oxidation. Our findings highlight the critical role of the surficial structure of T-Microgel, specifically its nanofabrication degree, in influencing the dynamic network's fabrication, thereby impacting yield and thixotropic properties. The surface charge of T-microgel does not significantly influence the process. This research not only elucidates the intricate dynamics of cellulose microgel/HPMC interaction but also provides fundamental insights essential for the development of innovative rheology modifiers tailored for high-content surfactant applications.


Subject(s)
Cellulose , Microgels , Rheology , Cellulose/chemistry , Microgels/chemistry , Surface-Active Agents/chemistry , Hypromellose Derivatives/chemistry , Cyclic N-Oxides/chemistry
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