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1.
Pediatr Dent ; 46(3): 204-208, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38822497

ABSTRACT

Purpose: The purpose of this study was to investigate the microleakage of atraumatic glass ionomer restorations with and without silver diammine fluoride (SDF) application. Restorations with SDF are termed silver-modified atraumatic restorations (SMART). Methods: Sixty carious extracted permanent teeth were randomly allocated to two SMART groups and two control groups (n equals 15 per group) for a total of four groups. After selective caries removal, test specimens were treated with 38 percent SDF and polyacrylic acid conditioner was applied and rinsed; teeth were restored with Fuji IX GP® glass ionomer (n equals 15) or with SMART Advantage™ glass ionomer (SAGI; n equals 15). For control groups, specimens were restored with their respective GI material after selective caries removal, both without SDF. Restored teeth were placed in Dulbecco's Phosphate-Buffered Saline solution at 37 degrees Celsius for 24 hours. Teeth were thermocycled between five and 55 degrees Celsius for 1,000 cycles, stained with two percent basic fuchsin, sectioned, and visually inspected for microleakage utilizing stereomicroscopy on a four-point scale. Data were statistically analyzed using Kruskal-Wallis one-way analysis of variance on ranks using Dunn's method (P<0.05). Results: Microleakage between the two SMART restoration groups was insignificant. SAGI alone demonstrated significantly more microleakage than all other groups. There was no statistical significance between the Fuji IX GP® control group and the two SMART restoration groups. Conclusions: This in vitro study indicated that silver diammine fluoride placed before glass ionomer restoration does not increase microleakage. Polyacrylic acid may be used after SDF placement without increasing microleakage.


Subject(s)
Dental Atraumatic Restorative Treatment , Dental Caries , Dental Leakage , Fluorides, Topical , Glass Ionomer Cements , Silver Compounds , Dental Leakage/prevention & control , Humans , Silver Compounds/chemistry , Glass Ionomer Cements/chemistry , Dental Atraumatic Restorative Treatment/methods , Fluorides, Topical/chemistry , Dental Caries/prevention & control , Cariostatic Agents/chemistry , Quaternary Ammonium Compounds/chemistry , Viscosity , Acrylic Resins/chemistry , Dental Restoration, Permanent/methods
2.
Pediatr Dent ; 46(3): 192-198, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38822501

ABSTRACT

Purpose: The purposes of this study were to evaluate the effect of silver diammine fluoride (SDF) on the shear bond strength (SBS) of pink opaquer (PO) compared to resin-modified glass ionomer (RMGI) and conventional composite (COMP) on demineralized dentin, and also to investigate the mode of failure (MOF). Methods: Sixty extracted third molars were prepared, demineralized for 14 days, and divided into four groups: (1) COMP; (2) SDF+PO; (3) SDF+RMGI; and (4) SDF+COMP (restoration size: two by two mm). SBS, MOF, modified adhesive remnant index (MARI), and remnant adhesive volume (RAV) were evaluated using an Instron® machine, light microscopy, 3D digital scanner ( 3Shape©), and GeoMagic Wrap© software. Results: There was no significant difference in SBS (MPa) among the COMP mean??standard deviation (2.5±1.59), SDF+COMP (2.28±1.05), SDF+PO (3.31±2.63), and SDF+RMGI groups (3.74±2.34). There was no significant difference in MOF and MARI among the four groups (P>0.05). There was no significant difference in RAV (mm3) among the COMP (0.5±0.33), SDF+COMP (0.39±0.44), SDF+PO (0.42±0.38), and SDF+RMGI groups (0.42±0.38; P>0.05). A significant correlation existed between MOF and RAV (R equals 0.721; P<0.001). MOF, MARI, and RAV did not show any correlations with SBS (P>0.05). Conclusions: Silver diammine fluoride does not affect shear bond strength between carious dentinal surface and tooth color restorative materials. The amount of material left on the interface is not related to the amount of shear force needed to break the restoration.


Subject(s)
Composite Resins , Dental Bonding , Dentin , Fluorides, Topical , Shear Strength , Silver Compounds , Humans , Silver Compounds/chemistry , Dentin/drug effects , Composite Resins/chemistry , Glass Ionomer Cements/chemistry , Quaternary Ammonium Compounds/chemistry , Materials Testing , Dental Restoration, Permanent/methods , Dental Materials/chemistry , Dental Stress Analysis , Tooth Demineralization/prevention & control , In Vitro Techniques , Acrylic Resins/chemistry , Color
3.
ACS Appl Mater Interfaces ; 16(23): 29867-29875, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38825754

ABSTRACT

Antimicrobial surfaces limit the spread of infectious diseases. To date, there is no antimicrobial coating that has widespread use because of short-lived and limited spectrum efficacy, poor resistance to organic material, and/or cost. Here, we present a paint based on waterborne latex particles that is supramolecularly associated with quaternary ammonium compounds (QACs). The optimal supramolecular pairing was first determined by immobilizing selected ions on self-assembled monolayers exposing different groups. The QAC surface loading density was then increased by using polymer brushes. These concepts were adopted to develop inexpensive paints to be applied on many different surfaces. The paint could be employed for healthcare and food production applications. Its slow release of QAC allows for long-lasting antimicrobial action, even in the presence of organic material. Its efficacy lasts for more than 90 washes, and importantly, once lost, it can readily be restored by spraying an aqueous solution of the QAC. We mainly tested cetyltrimethylammonium as QAC as it is already used in consumer care products. Our antimicrobial paint is broad spectrum as it showed excellent antimicrobial efficiency against four bacteria and four viruses.


Subject(s)
Quaternary Ammonium Compounds , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/pharmacology , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Paint , Surface Properties , Latex/chemistry , Latex/pharmacology , Microbial Sensitivity Tests , Bacteria/drug effects
4.
Proc Natl Acad Sci U S A ; 121(25): e2403273121, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38865266

ABSTRACT

In secondary active transporters, a relatively limited set of protein folds have evolved diverse solute transport functions. Because of the conformational changes inherent to transport, altering substrate specificity typically involves remodeling the entire structural landscape, limiting our understanding of how novel substrate specificities evolve. In the current work, we examine a structurally minimalist family of model transport proteins, the small multidrug resistance (SMR) transporters, to understand the molecular basis for the emergence of a novel substrate specificity. We engineer a selective SMR protein to promiscuously export quaternary ammonium antiseptics, similar to the activity of a clade of multidrug exporters in this family. Using combinatorial mutagenesis and deep sequencing, we identify the necessary and sufficient molecular determinants of this engineered activity. Using X-ray crystallography, solid-supported membrane electrophysiology, binding assays, and a proteoliposome-based quaternary ammonium antiseptic transport assay that we developed, we dissect the mechanistic contributions of these residues to substrate polyspecificity. We find that substrate preference changes not through modification of the residues that directly interact with the substrate but through mutations peripheral to the binding pocket. Our work provides molecular insight into substrate promiscuity among the SMRs and can be applied to understand multidrug export and the evolution of novel transport functions more generally.


Subject(s)
Quaternary Ammonium Compounds , Substrate Specificity , Quaternary Ammonium Compounds/metabolism , Quaternary Ammonium Compounds/chemistry , Crystallography, X-Ray , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/chemistry , Biological Transport , Membrane Transport Proteins/metabolism , Membrane Transport Proteins/chemistry , Membrane Transport Proteins/genetics , Drug Resistance, Multiple, Bacterial/genetics , Anti-Infective Agents, Local/metabolism , Anti-Infective Agents, Local/pharmacology , Anti-Infective Agents, Local/chemistry , Models, Molecular
5.
J Chromatogr A ; 1726: 464965, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38733925

ABSTRACT

Aristolochic acids (AAs) naturally occurring in the herbal genus Aristolochia are associated with a high risk of kidney failure, multiple tumors and cancers. However, approaches with high selectivity and rapidity for measuring AAs in biological samples are still inadequate. Inspired by the mechanism of AAs-induced nephrotoxicity, we designed a hybrid magnetic polymer-porous agarose (denoted as MNs@SiO2M@DNV-A), mimicking the effect of basic and aromatic residues of organic anion transporter 1 (OAT1) for efficient enriching aristolochic acid I (AA I) and aristolochic acid II (AA II) in the plasma. The monomers of vinylbenzyl trimethylammonium chloride (VBTAC), N-vinyl-2-pyrrolidinone (NVP) and divinylbenzene (DVB) were employed to construct the polymer layer, which provided a selective adsorption for AAs by multiple interactions. The porous agarose shell contributed to remove interfering proteins in the plasma samples. A magnetic solid-phase extraction (MSPE) based on the proposed composite enhanced the selectivity toward AA I and AA II in the plasma samples. In combination of HPLC analysis, the proposed method was proved to be applicable to fast and specific quantification of AAs in blood samples, which was characterized by a good linearity, high sensitivity, acceptable recovery, excellent repeatability and satisfactory reusability.


Subject(s)
Aristolochic Acids , Quaternary Ammonium Compounds , Sepharose , Solid Phase Extraction , Aristolochic Acids/chemistry , Aristolochic Acids/isolation & purification , Aristolochic Acids/blood , Sepharose/chemistry , Solid Phase Extraction/methods , Quaternary Ammonium Compounds/chemistry , Chromatography, High Pressure Liquid/methods , Porosity , Limit of Detection , Animals , Humans , Polymers/chemistry , Adsorption , Reproducibility of Results
6.
Int J Nanomedicine ; 19: 4235-4251, 2024.
Article in English | MEDLINE | ID: mdl-38766661

ABSTRACT

Purpose: In recent years, microfluidic technologies have become mainstream in producing gene therapy nanomedicines (NMeds) following the Covid-19 vaccine; however, extensive optimizations are needed for each NMed type and genetic material. This article strives to improve LNPs for pDNA loading, protection, and delivery, while minimizing toxicity. Methods: The microfluidic technique was optimized to form cationic or neutral LNPs to load pDNA. Classical "post-formulation" DNA addition vs "pre" addition in the aqueous phase were compared. All formulations were characterized (size, homogeneity, zeta potential, morphology, weight yield, and stability), then tested for loading efficiency, nuclease protection, toxicity, and cell uptake. Results: Optimized LNPs formulated with DPPC: Chol:DOTAP 1:1:0.1 molar ratio and 10 µg of DOPE-Rhod, had a size of 160 nm and good homogeneity. The chemico-physical characteristics of cationic LNPs worsened when adding 15 µg/mL of pDNA with the "post" method, while maintaining their characteristics up to 100 µg/mL of pDNA with the "pre" addition remaining stable for 30 days. Interestingly, neutral LNPs formulated with the same method loaded up to 50% of the DNA. Both particles could protect the DNA from nucleases even after one month of storage, and low cell toxicity was found up to 40 µg/mL LNPs. Cell uptake occurred within 2 hours for both formulations with the DNA intact in the cytoplasm, outside of the lysosomes. Conclusion: In this study, the upcoming microfluidic technique was applied to two strategies to generate pDNA-LNPs. Cationic LNPs could load 10x the amount of DNA as the classical approach, while neutral LNPs, which also loaded and protected DNA, showed lower toxicity and good DNA protection. This is a big step forward at minimizing doses and toxicity of LNP-based gene therapy.


Subject(s)
Cations , DNA , Plasmids , Plasmids/administration & dosage , Plasmids/chemistry , Humans , Cations/chemistry , DNA/chemistry , DNA/administration & dosage , Genetic Therapy/methods , Microfluidics/methods , Particle Size , Nanomedicine , COVID-19/prevention & control , Liposomes/chemistry , Transfection/methods , Nanoparticles/chemistry , SARS-CoV-2 , COVID-19 Vaccines/administration & dosage , COVID-19 Vaccines/chemistry , Quaternary Ammonium Compounds/chemistry , Fatty Acids, Monounsaturated
7.
Sci Rep ; 14(1): 12496, 2024 05 31.
Article in English | MEDLINE | ID: mdl-38821995

ABSTRACT

Designing materials capable of disinfecting water without releasing harmful by-products is an ongoing challenge. Here, we report a novel polycationic sponge material synthesized from chitosan derivatives and cellulose fibers, exhibiting antibacterial properties. The design of such material is based on three key principles. First, the formation of a highly porous structure through cryogelation for an extensive surface area. Second, the incorporation of cationic quaternary ammonium moieties onto chitosan to enhance bacterial adsorption and antibacterial activity. Lastly, the reinforcement of mechanical properties through integration of cellulose fibers. The presented sponge materials exhibit up to a 4-log (99.99%) reduction within 6 h against both gram-positive B. subtilis and gram-negative E. coli. Notably, QCHI90/Cell, with the highest surface charge, exhibits a 2-4.5 log reduction within 1 h of incubation time. The eco-friendly synthesis from water and readily available biomaterials, along with cost-effectiveness and simplicity, underscores its versatility and feasibility of upscaling. Together with its outstanding antibacterial activity, this macroporous biomaterial emerges as a promising candidate for water disinfection applications.


Subject(s)
Anti-Bacterial Agents , Biocompatible Materials , Cellulose , Chitosan , Escherichia coli , Water Purification , Escherichia coli/drug effects , Biocompatible Materials/chemistry , Cellulose/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Water Purification/methods , Chitosan/chemistry , Water Microbiology , Bacillus subtilis/drug effects , Porosity , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/pharmacology , Adsorption
8.
Molecules ; 29(9)2024 May 03.
Article in English | MEDLINE | ID: mdl-38731617

ABSTRACT

In this study, a library of 3,7-di(hetero)aryl-substituted 10-(3-trimethylammoniumpropyl)10H-phenothiazine salts is prepared. These title compounds and their precursors are reversible redox systems with tunable potentials. The Hammett correlation gives a very good correlation of the first oxidation potentials with σp parameters. Furthermore, the title compounds and their precursors are blue to green-blue emissive. Screening of the salts reveals for some derivatives a distinct inhibition of several pathogenic bacterial strains (Mycobacterium tuberculosis, Staphylococcus aureus, Escherichia coli, Aconetobacter baumannii, and Klebsiella pneumoniae) in the lower micromolar range.


Subject(s)
Anti-Bacterial Agents , Microbial Sensitivity Tests , Phenothiazines , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Phenothiazines/pharmacology , Phenothiazines/chemistry , Phenothiazines/chemical synthesis , Salts/chemistry , Salts/pharmacology , Staphylococcus aureus/drug effects , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/pharmacology , Quaternary Ammonium Compounds/chemical synthesis , Escherichia coli/drug effects , Oxidation-Reduction , Bacteria/drug effects , Molecular Structure , Structure-Activity Relationship
9.
J Chromatogr A ; 1727: 465011, 2024 Jul 19.
Article in English | MEDLINE | ID: mdl-38776604

ABSTRACT

Chiral enantiomers, especially the enantiomers of chiral drugs often exhibit different pharmacological activity, metabolism and toxicity, thus it is of great research significance to scientifically and reasonably develop single chiral drugs with low toxicity and high efficiency. Among them, high performance liquid chromatographic techniques based on chiral stationary phases (CSPs) has become one of the most attractive methods used to evaluate the enantiomeric purity of single-enantiomers compound of pharmacological relevance. In this work, pillar[5]arene functionalized with L- and D-histidine, respectively, were modified on the surface of mesoporous silica as novel chiral stationary phases called L/DHis-BP5-Sil. Notably, L/D-histidine had the characteristics of low steric hindrance and easy derivatization. Although the π-π interaction of imidazole group was weaker than that of benzene ring, the benzene ring bonding imidazole-conjugated ring in the structure produced better enantioseparation effect. The results showed that L/DHis-BP5-Sil can separate a variety of complex structural enantiomers with excellent reproducibility, thermal stability and separation performance. Hence, the unique advantage of the highly selective separation of L/DHis-BP5-Sil provides new insights into the enantioseparation field.


Subject(s)
Calixarenes , Histidine , Silicon Dioxide , Stereoisomerism , Silicon Dioxide/chemistry , Calixarenes/chemistry , Histidine/chemistry , Chromatography, High Pressure Liquid/methods , Porosity , Reproducibility of Results , Quaternary Ammonium Compounds/chemistry
10.
Org Biomol Chem ; 22(20): 4135-4144, 2024 05 22.
Article in English | MEDLINE | ID: mdl-38712466

ABSTRACT

Herein, we present an innovative synthetic approach for producing a diverse set of biobased oligomers. This method begins with olive oil and employs a wide variety of commercially available amino acids (AAs) as bio-organocatalysts, in addition to tetrabutylammonium iodide (TBAI) as a cocatalyst, to synthesize various biobased oligomers. These biobased oligomers were strategically prepared starting from epoxidized olive oil (EOO) and a variety of cyclic anhydrides (phthalic, PA; maleic, MA; succinic, SA; and glutaric, GA). Among the amino acids tested as bio-organocatalysts, L-glutamic acid (L-Glu) showed the best performance for the synthesis of both poly(EOO-co-PA) and poly(EOO-co-MA), exhibiting 100% conversion at 80 °C in 2 hours, whereas the formation of poly(EOO-co-SA) and poly(EOO-co-GA) required more extreme reaction conditions (72 hours under toluene reflux conditions). Likewise, we have succeeded in obtaining the trans isomer exclusively for the MA based-oligomer within the same synthetic framework. The obtained oligomers were extensively characterized using techniques including NMR, FT-IR, GPC and TGA. A series of computational simulations based on density functional theory (DFT) and post-Hartree Fock (post-HF) methods were performed to corroborate our experimental findings and to obtain an understanding of the reaction mechanisms.


Subject(s)
Amino Acids , Polymerization , Catalysis , Amino Acids/chemistry , Amino Acids/chemical synthesis , Green Chemistry Technology , Plant Oils/chemistry , Polymers/chemistry , Polymers/chemical synthesis , Molecular Structure , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/chemical synthesis
11.
Int J Biol Macromol ; 269(Pt 2): 132153, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38729494

ABSTRACT

Hollow vesicles are promising in water treatment due to their unique structure of the membrane and inner cavity. However, the adsorption capacity needs to be improved for targeted pollutants. Herein, millimeter-scale hollow vesicles were prepared with a one-step process of sequential stirring and grafting using chitosan, diallyldimethylammonium chloride, and sodium alginate as raw materials with the purpose of efficient removal of anionic dyes from wastewater. The composite vesicles were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. The hollow vesicles showed the structure of the cationic membrane and the inner cavity, facilitating the dye adsorption. The adsorption capacity for the anionic dye Reactive Black 5 reached 698.1 mg/g, more than twice that of the binary composite vesicles without graft. The adsorption kinetics and isotherm data coincided with the pseudo-second-order and Langmuir models, respectively, and the adsorption mechanism was monolayer chemisorption. Moreover, the vesicles worked well in wide ranges of environment pH, temperature, and co-existing pollutants. They also possessed excellent cyclic regeneration performance, in which 93 % of the initial adsorption capacity was maintained after four cycles. These results indicate that the millimeter-scale hollow vesicles exhibit broad application prospects for wastewater purification.


Subject(s)
Alginates , Chitosan , Coloring Agents , Quaternary Ammonium Compounds , Water Pollutants, Chemical , Water Purification , Chitosan/chemistry , Alginates/chemistry , Adsorption , Quaternary Ammonium Compounds/chemistry , Water Pollutants, Chemical/chemistry , Coloring Agents/chemistry , Water Purification/methods , Kinetics , Anions/chemistry , Hydrogen-Ion Concentration , Wastewater/chemistry , Naphthalenesulfonates/chemistry , Allyl Compounds
12.
Int J Mol Sci ; 25(9)2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38731869

ABSTRACT

This review provides a comprehensive overview of recent advancements in the design and synthesis of biologically active quaternary ammonium compounds (QACs). The covered scope extends beyond commonly reviewed antimicrobial derivatives to include synthetic agents with antifungal, anticancer, and antiviral properties. Additionally, this review highlights examples of quaternary ammonium compounds exhibiting activity against protozoa and herbicidal effects, as well as analgesic and anesthetic derivatives. The article also embraces the quaternary-ammonium-containing cholinesterase inhibitors and muscle relaxants. QACs, marked by their inherent permanent charge, also find widespread usage across diverse domains such as fabric softeners, hair conditioners, detergents, and disinfectants. The effectiveness of QACs hinges greatly on finding the right equilibrium between hydrophilicity and lipophilicity. The ideal length of the alkyl chain varies according to the unique structure of each QAC and its biological settings. It is expected that this review will provide comprehensive data for medicinal and industrial chemists to design and develop novel QAC-based products.


Subject(s)
Quaternary Ammonium Compounds , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/chemical synthesis , Quaternary Ammonium Compounds/pharmacology , Humans , Animals , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/chemistry , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/pharmacology , Cholinesterase Inhibitors/chemistry
13.
Colloids Surf B Biointerfaces ; 239: 113932, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38749165

ABSTRACT

Quaternary ammonium salts (QAS) are widely used in medicine, industry and agriculture as disinfectants, biocides, and fungicides. QAS have the ability to coat various surfaces, prevent adhesion of microorganisms to them and inhibit the formation of biofilm. A group of surfactants derived from benzoic acid with different chemical structures was tested: monomeric QAS with different alkyl chain lengths (C12, C14, C16), gemini QAS containing 12-carbon alkyl chains and linkers of various lengths (3,4,6 methylene groups), as well as multifunctional QAS. Among the tested surfactants, monomeric QAS showed the highest bactericidal and fungicidal activity. All three groups of tested compounds inhibited the filamentation of C. albicans. The best antimicrobial activity was demonstrated by the monomeric surfactant C12AA, while the multifunctional equivalent (2xC12AA) was characterized by good anti-adhesive activity. All tested compounds are non-mutagenic and cause low hemolysis of sheep erythrocytes. Multifunctional and gemini surfactants are also non-toxic.


Subject(s)
Candida albicans , Hemolysis , Microbial Sensitivity Tests , Surface-Active Agents , Surface-Active Agents/pharmacology , Surface-Active Agents/chemistry , Surface-Active Agents/chemical synthesis , Sheep , Animals , Candida albicans/drug effects , Hemolysis/drug effects , Erythrocytes/drug effects , Biofilms/drug effects , Anti-Infective Agents/pharmacology , Anti-Infective Agents/chemistry , Anti-Infective Agents/chemical synthesis , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/pharmacology , Quaternary Ammonium Compounds/chemical synthesis , Antifungal Agents/pharmacology , Antifungal Agents/chemical synthesis , Antifungal Agents/chemistry
14.
ACS Nano ; 18(20): 12905-12916, 2024 May 21.
Article in English | MEDLINE | ID: mdl-38721835

ABSTRACT

For most frequent respiratory viruses, there is an urgent need for a universal influenza vaccine to provide cross-protection against intra- and heterosubtypes. We previously developed an Escherichia coli fusion protein expressed extracellular domain of matrix 2 (M2e) and nucleoprotein, named NM2e, and then combined it with an aluminum adjuvant, forming a universal vaccine. Although NM2e has demonstrated a protective effect against the influenza virus in mice to some extent, further improvement is still needed for the induction of immune responses ensuring adequate cross-protection against influenza. Herein, we fabricated a cationic solid lipid nanoadjuvant using poly(lactic acid) (PLA) and dimethyl-dioctadecyl-ammonium bromide (DDAB) and loaded NM2e to generate an NM2e@DDAB/PLA nanovaccine (Nv). In vitro experiments suggested that bone marrow-derived dendritic cells incubated with Nv exhibited ∼4-fold higher antigen (Ag) uptake than NM2e at 16 h along with efficient activation by NM2e@DDAB/PLA Nv. In vivo experiments revealed that Ag of the Nv group stayed in lymph nodes (LNs) for more than 14 days after initial immunization and DCs in LNs were evidently activated and matured. Furthermore, the Nv primed T and B cells for robust humoral and cellular immune responses after immunization. It also induced a ratio of IgG2a/IgG1 higher than that of NM2e to a considerable extent. Moreover, NM2e@DDAB/PLA Nv quickly restored body weight and improved survival of homo- and heterosubtype influenza challenged mice, and the cross-protection efficiency was over 90%. Collectively, our study demonstrated that NM2e@DDAB/PLA Nv could offer notable protection against homo- and heterosubtype influenza virus challenges, offering the potential for the development of a universal influenza vaccine.


Subject(s)
Adjuvants, Immunologic , Influenza Vaccines , Polyesters , Quaternary Ammonium Compounds , Influenza Vaccines/immunology , Influenza Vaccines/chemistry , Influenza Vaccines/administration & dosage , Animals , Mice , Polyesters/chemistry , Adjuvants, Immunologic/chemistry , Adjuvants, Immunologic/pharmacology , Quaternary Ammonium Compounds/chemistry , Female , Mice, Inbred BALB C , Orthomyxoviridae Infections/prevention & control , Orthomyxoviridae Infections/immunology , Nanoparticles/chemistry , Cross Protection/immunology , Adjuvants, Vaccine/chemistry , Viral Matrix Proteins/immunology
15.
Carbohydr Polym ; 337: 122188, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38710565

ABSTRACT

Growing plants in karst areas tends to be difficult due to the easy loss of water and soil. To enhance soil agglomeration, water retention, and soil fertility, this study developed a physically and chemically crosslinked hydrogel prepared from quaternary ammonium guar gum and humic acid. The results showed that non-covalent dynamic bonds between the two components delayed humic acid release into the soil, with a release rate of only 35 % after 240 h. The presence of four hydrophilic groups (quaternary ammonium, hydroxyl, carboxyl, and carbonyl) in the hydrogel more than doubled the soil's water retention capacity. The interaction between hydrogel and soil minerals (especially carbonate and silica) promoted hydrogel-soil and soil­carbonate adhesion, and the adhesion strength between soil particles was enhanced by 650 %. Moreover, compared with direct fertilization, this degradable hydrogel not only increased the germination rate (100 %) and growth status of mung beans but also reduced the negative effects of excessive fertilization on plant roots. The study provides an eco-friendly, low-cost, and intelligent system for soil improvement in karst areas. It further proves the considerable application potential of hydrogels in agriculture.


Subject(s)
Galactans , Humic Substances , Hydrogels , Mannans , Plant Gums , Quaternary Ammonium Compounds , Soil , Plant Gums/chemistry , Galactans/chemistry , Mannans/chemistry , Hydrogels/chemistry , Soil/chemistry , Quaternary Ammonium Compounds/chemistry , Fertilizers , Delayed-Action Preparations/chemistry , Germination/drug effects , Water/chemistry
16.
Biomacromolecules ; 25(6): 3731-3740, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38712827

ABSTRACT

Interface engineering is essential for cellulosic fiber-reinforced polymer composites to achieve high strength and toughness. In this study, carboxymethyl cellulose (CMC) functionalized with hydrophobic quaternary ammonium ions (QAs) were utilized to modify the interface between holocellulose fibers (HF) and acrylic resin. The wet HF/CMC papers were prepared by vacuum filtration, akin to papermaking, followed by cationic ion exchange with different hydrophobic QAs. Subsequently, the modified papers were dried, impregnated with an acrylic resin monomer, and cured to produce transparent composite films. The effect of the hydrophobic QA moieties on the structure and optical and mechanical properties of the HF/CMC/acrylic resin composites were investigated. The composite film with cetyltrimethylammonium (CTA)-functionalized CMC showed high optical transmittance (87%) with low haze (43%), while the composite film with phenyltrimethylammonium (PTMA)-functionalized CMC demonstrated high Young's modulus of 7.6 GPa and high tensile strength of 180 MPa. These properties are higher than those of the composites prepared through covalent interfacial modification strategies. The results highlighted the crucial role of hydrophobic functionalized CMCs in facilitating homogeneous resin impregnation in the HF fiber network, producing a composite with enhanced interfacial adhesion strength, increased optical transparency, and mechanical strength. This facile use of hydrophobic CMCs as interfacial compatibilizers provides an energy-efficient route for preparing transparent, thin, and flexible composite films favorable in optoelectronic applications.


Subject(s)
Acrylic Resins , Carboxymethylcellulose Sodium , Hydrophobic and Hydrophilic Interactions , Tensile Strength , Carboxymethylcellulose Sodium/chemistry , Acrylic Resins/chemistry , Quaternary Ammonium Compounds/chemistry , Cellulose/chemistry , Elastic Modulus
17.
Talanta ; 276: 126290, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38805755

ABSTRACT

A very sensitive electrochemical biosensor, with haemoglobin (Hb) as its basis, has been created to quantify hydrogen peroxide (H2O2), an essential marker in environmental monitoring, food safety, and medical diagnosis. The sensor uses a simple, eco-friendly preparation method. Hb was immobilised on manganese dioxide nanostructure/gold nanoparticles/poly-diallydimethylammonium chloride-functionalised multiwalled carbon nanotubes (PDDA-MWCNT/AuNP/MnO2), characterised using various techniques: amperometry, voltammetry, X-ray diffraction (XRD), and transmission electron microscopy (TEM). Nafion was used as a binder membrane to preserve the biological and electrochemical properties of the protein on the modified electrode. In comparison to earlier research, the novel biosensor had a lower detection limit (1.83 µM) and a limit of quantification (6.11 µM) (S/N = 3) for H2O2. It also exhibited notable reproducibility, long-term stability, and repeatability. It was effectively used to measure the amount of H2O2 in cow milk and orange juice, yielding recoveries in the order of 98.90-99.53 % with RSDs less than 5.0 %, which makes it a promising biosensor for food control.


Subject(s)
Biosensing Techniques , Electrochemical Techniques , Gold , Hemoglobins , Hydrogen Peroxide , Manganese Compounds , Metal Nanoparticles , Milk , Nanotubes, Carbon , Oxides , Quaternary Ammonium Compounds , Hydrogen Peroxide/chemistry , Hydrogen Peroxide/analysis , Gold/chemistry , Hemoglobins/analysis , Hemoglobins/chemistry , Biosensing Techniques/methods , Manganese Compounds/chemistry , Metal Nanoparticles/chemistry , Quaternary Ammonium Compounds/chemistry , Nanotubes, Carbon/chemistry , Oxides/chemistry , Electrochemical Techniques/methods , Milk/chemistry , Animals , Polyethylenes/chemistry , Cattle , Fruit and Vegetable Juices/analysis , Limit of Detection , Electrodes
18.
Anal Methods ; 16(19): 3030-3038, 2024 May 16.
Article in English | MEDLINE | ID: mdl-38682263

ABSTRACT

In this work, a sensitive colorimetric bioassay method based on a poly(adenine) aptamer (polyA apt) and gold nanoparticles (AuNPs) was developed for the determination of aflatoxin B1 (AFB1). The polyA apt, adsorbed on the AuNPs, especially can bind to the analyte while deterring non-specific interactions. This nano aptasensor uses cationic polymer poly(diallyl dimethyl ammonium chloride) (PDDA), as an aggregating agent, to aggregate gold nanoparticles. PolyA apt-decorated gold nanoparticles (AuNPs/polyA apt) show resistance to PDDA-induced aggregation and maintains their dispersed state (red color) with the optical absorbance signal at λ = 520 nm. However, in the presence of AFB1 in the assay solution, the specific aptamer reacts with high affinity and folds into its three-dimensional form. Aggregation of AuNPs induced by PDDA caused their optical signal shift to λ = 620 nm (blue color). AFB1 concentration in the bioassay solution determines the amount of optical signal shift. Therefore, optical density ratio in two wavelengths (A620/520) can be used as a sturdy colorimetric signal to detect the concentration of aflatoxin B1. AFB1 was linearly detected between 0.5 and 20 ng mL-1, with a detection limit of 0.09 ng mL-1 (S/N = 3). The fabricated aptasensor was applied to the detection of AFB1 in real corn samples.


Subject(s)
Aflatoxin B1 , Aptamers, Nucleotide , Colorimetry , Gold , Metal Nanoparticles , Zea mays , Aflatoxin B1/analysis , Aflatoxin B1/chemistry , Gold/chemistry , Colorimetry/methods , Zea mays/chemistry , Metal Nanoparticles/chemistry , Aptamers, Nucleotide/chemistry , Biosensing Techniques/methods , Poly A/chemistry , Limit of Detection , Food Contamination/analysis , Quaternary Ammonium Compounds/chemistry , Polyethylenes
19.
Water Res ; 256: 121539, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38583335

ABSTRACT

Inorganic coagulants such as poly aluminum ferric chloride (Al/Fe) are applied conventionally to sewage sludge dewatering and can be retained in the sludge cake, causing its conductivity to increase and generate secondary pollution. To reduce these disadvantages, there is a need to develop alternative, more sustainable chemicals as substitutes for conventional inorganic coagulants. In the present investigation, the application of a polymeric chitosan quaternary ammonium salt (CQAS) is explored as a complete, or partial, replacement for Al/Fe in the context of sludge dewatering processes. Laboratory experiments using digested sewage sludge showed that CQAS could effectively substitute for over 80 % of the Al/Fe inorganic coagulant in the sludge dewatering process. This substitution resulted in a reduction of sludge cake conductivity by more than 50 %. Simulation of sludge dewatering curves and imaging of the sludge surface indicated that the addition of CQAS led to an increase in nanosized pores, and a decrease in the specific resistance of the sludge filter cake as the dosage of Al/Fe decreased to around 30 %. The variations of fluorescence emission, quantum yield and carboxylic and amino groups, suggested that the chelating of Al/Fe decreased due to the bridging effects of CQAS. The CQAS had different flocculation bridging effects on various EPS fractions, which varied the amount of protein chelated with Al/Fe in each fraction. This study provides new information about the benefits of replacing conventional inorganic coagulants with natural organic polymers for sewage sludge dewatering, in terms of reduced sludge cake conductivity and greater dry solids content.


Subject(s)
Chitosan , Ferric Compounds , Sewage , Sewage/chemistry , Chitosan/chemistry , Ferric Compounds/chemistry , Quaternary Ammonium Compounds/chemistry , Flocculation , Chlorides/chemistry , Waste Disposal, Fluid/methods , Aluminum/chemistry
20.
Colloids Surf B Biointerfaces ; 238: 113914, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38663310

ABSTRACT

Combining with various antibacterial mechanisms is the preferred strategy to fabricate coatings with effective antibacterial performance. Herein, Cu2O nanoparticles and dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride, a kind of quaternary ammonium salt (QAS), were simultaneously incorporated into a moisture-curable acrylic resin in order to achieve both contact-killing and release-killing abilities for antibacterial coatings. The surface morphology, surface composition and basic properties of the coatings were thoroughly characterized. The antibacterial performance of the coatings was determined by in-vitro bacteriostatic test. Under the constant total mass fraction of antibacterial agents, both Cu2O and QAS content possessed the highest value on the coating surface at Cu2O/QAS mass ratio of 1:1, and correspondingly, the coatings reached sterilizing rate above 99 % against both E. coli and S. loihica, indicating the existence of synergistic effect between Cu2O and QAS. The synergistic antibacterial mechanism of the coatings involved two aspects. Firstly, the combination of contact-killing and release-killing biocides resulted in high bactericidal and antibiofilm activity against different bacteria. Further, the grafting of QAS molecules on the surface of Cu2O particles brought about the spontaneous migration of nanoparticles to the coating surface. The interaction between Cu2O and QAS also inhibited the phase separation of QAS and prolonged the release of Cu2+ at the same time. The coatings, therefore, exhibited stable antibacterial performance at varied service conditions.


Subject(s)
Anti-Bacterial Agents , Copper , Escherichia coli , Microbial Sensitivity Tests , Quaternary Ammonium Compounds , Surface Properties , Copper/chemistry , Copper/pharmacology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Quaternary Ammonium Compounds/chemistry , Quaternary Ammonium Compounds/pharmacology , Escherichia coli/drug effects , Particle Size , Nanoparticles/chemistry , Metal Nanoparticles/chemistry , Acrylic Resins/chemistry , Acrylic Resins/pharmacology , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/pharmacology
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