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1.
Virulence ; 15(1): 2397503, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39282885

RESUMEN

Cationic biocides (CBs), which include quaternary ammonium compounds (QACs), are employed to mitigate the spread of infectious bacteria, but resistance to such surface disinfectants is rising. CB exposure can have profound phenotypic implications that extend beyond allowing microorganisms to persist on surfaces. Pseudomonas aeruginosa is a deadly bacterial pathogen that is intrinsically tolerant to a wide variety of antimicrobials and is commonly spread in healthcare settings. In this study, we pursued resistance selection assays to the QAC benzalkonium chloride and quaternary phosphonium compound P6P-10,10 to assess the phenotypic effects of CB exposure in P. aeruginosa PAO1 and four genetically diverse, drug-resistant clinical isolates. In particular, we sought to examine how CB exposure affects defensive strategies and the virulence-associated "offensive" strategies in P. aeruginosa. We demonstrated that development of resistance to BAC is associated with increased production of virulence-associated pigments and alginate as well as pellicle formation. In an in vivo infection model, CB-resistant PAO1 exhibited a decreased level of virulence compared to wild type, potentially due to an observed fitness cost in these strains. Taken together, these results illustrate the significant consequence CB resistance exerts on the virulence-associated phenotypes of P. aeruginosa.


Asunto(s)
Desinfectantes , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Factores de Virulencia , Pseudomonas aeruginosa/patogenicidad , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/genética , Desinfectantes/farmacología , Virulencia , Factores de Virulencia/genética , Infecciones por Pseudomonas/microbiología , Animales , Compuestos de Benzalconio/farmacología , Farmacorresistencia Bacteriana , Ratones , Compuestos de Amonio Cuaternario/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Adaptación Fisiológica , Cationes/farmacología
2.
Commun Biol ; 7(1): 1158, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39284859

RESUMEN

Diseases caused by S. pneumoniae are the leading cause of child mortality. As antibiotic resistance of S. pneumoniae is rising, vaccination remains the most recommended solution. However, the existing pneumococcal polysaccharides vaccine (Pneumovax® 23) proved only to induce T-independent immunity, and strict cold chain dependence of the protein conjugate vaccine impedes its promotion in developing countries, where infections are most problematic. Affordable and efficient vaccines against pneumococcus are therefore in high demand. Here, we present an intranasal vaccine Lipo+CPS12F&αGC, containing the capsular polysaccharides of S. pneumoniae 12F and the iNKT agonist α-galactosylceramide in cationic liposomes. In BALB/cJRj mice, the vaccine effectively activates iNKT cells and promotes B cells maturation, stimulates affinity-matured IgA and IgG production in both the respiratory tract and systemic blood, and displays sufficient protection both in vivo and in vitro. The designed vaccine is a promising, cost-effective solution against pneumococcus, which can be expanded to cover more serotypes and pathogens.


Asunto(s)
Administración Intranasal , Inmunidad Humoral , Liposomas , Ratones Endogámicos BALB C , Infecciones Neumocócicas , Vacunas Neumococicas , Streptococcus pneumoniae , Animales , Streptococcus pneumoniae/inmunología , Ratones , Vacunas Neumococicas/inmunología , Vacunas Neumococicas/administración & dosificación , Inmunidad Humoral/efectos de los fármacos , Infecciones Neumocócicas/prevención & control , Infecciones Neumocócicas/inmunología , Femenino , Anticuerpos Antibacterianos/sangre , Polisacáridos Bacterianos/inmunología , Polisacáridos Bacterianos/administración & dosificación , Cationes
3.
ACS Appl Mater Interfaces ; 16(38): 51318-51332, 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39276181

RESUMEN

The development of intelligent multifunctional nanopesticides featuring enhanced foliage affinity and hierarchical target release is increasingly pivotal in modern agriculture. In this study, a novel cationic amphiphilic comb-shaped polymer, termed PEI-TA, was prepared via a one-step Michael addition between low-molecular-weight biodegradable polyethylenimine (PEI) and tetradecyl acrylate (TA), followed by neutralization with acetic acid. Using the emulsifier PEI-TA, a positively charged avermectin (AVM) nanoemulsion was prepared via a phase inversion emulsification process. Under optimal formulation, the obtained AVM nanoemulsion (defined as AVM@PEI-TA) demonstrated exceptional properties, including small size (as low as 67.6 nm), high encapsulation efficiency (up to 87.96%), and high stability toward shearing, storage, dilution, and UV irradiation. The emulsifier endowed AVM@PEI-TA with a pronounced thixotropy, so that the droplets exhibited no splash and bounce when they were sprayed on the cabbage leaf. Owing to the electrostatic attraction between the emulsifier and the leaf, AVM@PEI-TA showed improved leaf adhesion, better deposition, and higher washing resistance in contrast to both its negatively charged counterpart and AVM emulsifiable concentrate (AVM-EC). Compared to the large-sized particles, the small-sized particles of the AVM nanoemulsion more effectively traveled long distances through the vascular system of veins after entering the leaf apoplast. Moreover, the nanoparticles lost stability when exposed to multidimensional stimuli, including pH, temperature, esterase, and ursolic acid individually or simultaneously, thereby promoting the release of AVM. The release mechanisms were discussed for understanding the important role of the emulsifier in nanopesticides.


Asunto(s)
Emulsionantes , Emulsiones , Ivermectina , Ivermectina/análogos & derivados , Ivermectina/química , Ivermectina/farmacología , Emulsiones/química , Emulsionantes/química , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacología , Hojas de la Planta/química , Polietileneimina/química , Nanopartículas/química , Brassica/química , Liberación de Fármacos , Tamaño de la Partícula , Acrilatos/química , Cationes/química , Polímeros/química
4.
J Biomed Mater Res B Appl Biomater ; 112(10): e35487, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39318330

RESUMEN

Long double-stranded (ds)RNA, a potent stimulator of type I interferon and the innate immune response. In the present study, we demonstrated, for the first time, the efficacy of cationic polystyrene latex nanostructures (clNPs) as a dsRNA carrier, improving cellular delivery and robustly potentiating the immunostimulatory capacity of dsRNA in the ovarian cancer cell line SKOV3. The clNPs complexed with an in vitro transcribed dsRNA molecule, were bound by SKOV3 cells, and had increased cellular association compared to uncomplexed clNPs. clNPs complexed with dsRNA induced a more robust innate immune response compared to dsRNA alone. Transcript expression of two interferon-stimulated genes, were increased 47- and 108-fold over dsRNA and induced a significant antiviral state against vesicular-stomatitis virus, resulting in a 3.3-fold improvement on the efficacy of dsRNA. These data highlight the potential of polystyrene latex nanostructures as dsRNA carriers for anticancer immunotherapies, improving the uptake and efficacy of the nucleic acid.


Asunto(s)
Neoplasias Ováricas , Poliestirenos , ARN Bicatenario , Femenino , Poliestirenos/química , Poliestirenos/farmacología , Humanos , Neoplasias Ováricas/patología , Línea Celular Tumoral , ARN Bicatenario/química , Látex/química , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Cationes/química , Nanopartículas/química
5.
J Chem Phys ; 161(12)2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39319660

RESUMEN

As a precursor to various reactive nitrogen species formed in biological systems, nitric oxide (•NO) participates in numerous processes, including enhancing DNA radiosensitivity in ionizing radiation-based radiotherapy. Forming guanine radical cations is another common DNA lesion resulting from ionization and oxidation damage. As such, the interaction of •NO with guanine radical cations (G•+) may contribute to the radiosensitization of •NO. An intriguing aspect of this process is the participation of multiple spin configurations in the reaction, including open-shell singlet 1,OS[G•+(↑)⋯(↓)•NO], closed-shell singlet 1,CS[G(↑↓)⋯NO+], and triplet 3[G•+(↑)⋯(↑)•NO]. In this study, the reactions of •NO with both unsubstituted guanine radical cations (in the 9HG•+ conformation) and 9-methylguanine radical cations (9MG•+, a guanosine-mimicking model compound) were investigated in the absence and presence of monohydration of radical cations. Kinetic-energy dependent reaction product ions and cross sections were measured using an electrospray ionization guided-ion beam tandem mass spectrometer. The reaction mechanisms, kinetics, and dynamics were comprehended by interpreting the reaction potential energy surface using spin-projected density functional theory, coupled cluster theory, and multiconfiguration complete active space second-order perturbation theory, followed by RRKM kinetics modeling. The combined experimental and computational findings revealed closed-shell singlet 1,CS[7-NO-9MG]+ as the major, exothermic product and triplet 3[8-NO-9MG]+ as the minor, endothermic product. Singlet biradical products were not detected due to high reaction endothermicities, activation barriers, and inherent instability.


Asunto(s)
Cationes , Electrones , Guanina , Óxido Nítrico , Guanina/química , Guanina/análogos & derivados , Óxido Nítrico/química , Cinética , Radicales Libres/química , Cationes/química , Teoría Funcional de la Densidad
6.
Carbohydr Polym ; 345: 122581, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39227110

RESUMEN

High methyl-esterified citrus pectin (HMCP) is often used as a thickness in food products and is considered a poor emulsifier, especially in neutral pH solutions. Our previous findings show that the emulsifying capacity of HMCP could be significantly enhanced by calcium cations. Besides, the pH of the solution decreased in the presence of calcium cations. However, the impact of solution pH on HMCP emulsifying capacity in the presence of calcium cations is unclear. In this study, the pH of the HMCP solution was adjusted from 3.00 to 8.00 before adding calcium cations. The solution properties and emulsifying properties were analyzed in light of the existence of calcium cations. The results showed that the pH of the HMCP solutions decreased after bringing calcium cations into them. Calcium cations could change the solution rheological properties, particle size distributions and morphologies, and the particle microenvironmental hydrophobic areas in HMCP solutions while increasing the pH of HMCP solutions, contributing to improving the emulsifying capacity of HMCP. HMCP had the best emulsifying ability when the pH of the HMCP solutions was kept at a neutral level. This research gives us new ideas to adjust the emulsifying property of HMCP.


Asunto(s)
Calcio , Emulsionantes , Pectinas , Pectinas/química , Concentración de Iones de Hidrógeno , Calcio/química , Emulsionantes/química , Reología , Emulsiones/química , Tamaño de la Partícula , Cationes/química , Interacciones Hidrofóbicas e Hidrofílicas , Esterificación , Citrus/química
7.
AAPS PharmSciTech ; 25(7): 213, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39266895

RESUMEN

To overcome the challenges associated with the co-delivery of AuNPs (gold nanoparticles) and miRNA as an anti-breast cancer combination therapy, niosomal systems were developed using Span 60, cholesterol, and a cationic lipid (CTAB), and the formulations were optimized using Box-Behnken experimental design. The niosomal formulations with the smallest size were selected for further optimization of size, surface charge, entrapment efficiency, and stability. To achieve this, AuNPs and DSPE-PEG2000 (2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000)were added to the formulation. The optimized niosomal formulation could effectively encapsulate AuNPs with an entrapment efficiency of 34.49% ± 0.84 and a spherical particle size of 153.6 ± 4.62 nm. The incorporation of PEG and CTAB led to notable enhancements in the overall characteristics of the delivery system. To evaluate the effectiveness of the combination therapy, various assessments such as cytotoxicity, apoptosis, and gene expression properties were conducted. The results demonstrated that the combination delivery using the new C-PEG-Nio-AuNPs (cationic pegylated niosomal gold nanoparticles) system and miRNA had the lowest IC50, the highest apoptosis rate, and the most significant upregulation of miRNA and BAX/BCL2 expression in MCF-7 cell growth. In conclusion, this innovative co-delivery approach represents a promising breakthrough in the development of therapeutic agents for breast cancer treatment. By combining multiple therapeutic agents within a single delivery system, this method has the potential to enhance treatment efficacy, reduce side effects, and improve patient outcomes.


Asunto(s)
Neoplasias de la Mama , Oro , Liposomas , Nanopartículas del Metal , MicroARNs , Tamaño de la Partícula , Polietilenglicoles , Oro/química , Humanos , MicroARNs/administración & dosificación , Células MCF-7 , Polietilenglicoles/química , Nanopartículas del Metal/química , Liposomas/química , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Cationes/química , Apoptosis/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Supervivencia Celular/efectos de los fármacos , Fosfatidiletanolaminas/química
8.
ACS Appl Bio Mater ; 7(9): 5784-5794, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39226406

RESUMEN

Hydrated dispersions containing equimolar mixtures of cationic and anionic amphiphiles, referred to as catanionic systems, exhibit synergistic physicochemical properties, and mixing single-chain cationic and anionic lipids can lead to the spontaneous formation of vesicles as well as other phase structures. In the present work, we have characterized two catanionic systems prepared by mixing N-acyltaurines (NATs) and sarcosine alkyl esters (SAEs) bearing 11 and 12 C atoms in the acyl/alkyl chains. Turbidimetric and isothermal titration calorimetric studies revealed that both NATs form equimolar complexes with SAEs having matching acyl/alkyl chains. The three-dimensional structure of the sarcosine lauryl ester (lauryl sarcosinate, LS)-N-lauroyltaurine (NLT) equimolar complex has been determined by single-crystal X-ray diffraction. The LS-NLT equimolar complex is stabilized by electrostatic attraction and multiple hydrogen bonds, including classical, strong N-H···O hydrogen bonds as well as several C-H···O hydrogen bonds between the two amphiphiles. DSC studies showed that both equimolar complexes show single sharp phase transitions. Transmission electron microscopy and dynamic light scattering studies have demonstrated that the LS-NLT catanionic complex assemblies yield stable medium-sized vesicles (diameter 280-350 nm). These liposomes were disrupted at high pH, suggesting that the designed catanionic complexes can be used to develop base-labile drug delivery systems. In vitro studies with these catanionic liposomes showed efficient entrapment (73% loading) and release of the anticancer drug 5-fluorouracil in the physiologically relevant pH range of 6.0-8.0. The release rate was highest at pH 8.0, reaching about 78%, 90%, and 100% drug release at 2, 6, and 12 h, respectively. These observations indicate that LS-NLT catanionic vesicles will be useful for designing drug delivery systems, particularly for targeting organs such as the colon, which are inherently at basic pH.


Asunto(s)
Materiales Biocompatibles , Fluorouracilo , Tamaño de la Partícula , Fluorouracilo/química , Estructura Molecular , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Ensayo de Materiales , Cationes/química , Sarcosina/química , Sarcosina/análogos & derivados , Ésteres/química , Humanos , Liposomas/química
9.
Anal Chim Acta ; 1328: 343162, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39266194

RESUMEN

BACKGROUND: Capillary zone electrophoresis-tandem mass spectrometry (CZE-MS/MS) has become a valuable analytical technique in top-down proteomics (TDP). CZE-MS/MS-based TDP typically employs separation capillaries with neutral coatings (i.e., linear polyacrylamide, LPA). However, issues related to separation resolution and reproducibility remain with the LPA-coated capillaries due to the unavoidable non-specific protein adsorption onto the capillary wall. Cationic coatings can be critical alternatives to LPA coating for CZE-MS/MS-based TDP due to the electrostatic repulsion between the positively charged capillary inner wall and proteoform molecules in the acidic separation buffer. Unfortunately, there are only very few studies using cationic coating-based CZE-MS/MS for TDP studies. RESULTS: In this work, we aimed to develop a simple and efficient approach for preparing separation capillaries with a cationic coating, i.e., poly (acrylamide-co-(3-acrylamidopropyl) trimethylammonium chloride [PAMAPTAC]) for CZE-MS/MS-based TDP. The PAMAPTAC coating-based CZE-MS produced significantly better separation resolution of proteoforms compared to the traditionally used LPA-coated approach. It achieved reproducible separation and measurement of a simple proteoform mixture and a complex proteome sample (i.e., a yeast cell lysate) regarding migration time, proteoform intensity, and the number of proteoform identifications. The PAMAPTAC coating-based CZE-MS enabled the detection of large proteoforms (≥30 kDa) from the yeast cell lysate reproducibly without any size-based prefractionation. Interestingly, the mobility of proteoforms using the PAMAPTAC coating can be predicted accurately using a simple semi-empirical model. SIGNIFICANCE: The results render the PAMAPTAC coating as a valuable alternative to the LPA coating to advance CZE-MS-based TDP towards high-resolution separation and highly reproducible measurement of proteoforms in complex samples.


Asunto(s)
Cationes , Electroósmosis , Electroforesis Capilar , Proteómica , Electroforesis Capilar/métodos , Proteómica/métodos , Cationes/química , Espectrometría de Masas en Tándem/métodos , Saccharomyces cerevisiae/química
10.
J Phys Chem B ; 128(36): 8687-8700, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39223472

RESUMEN

Aromatic residues can participate in various biomolecular interactions, such as π-π, cation-π, and CH-π interactions, which are essential for protein structure and function. Here, we re-evaluate the geometry and energetics of these interactions using quantum mechanical (QM) calculations, focusing on pairwise interactions involving the aromatic amino acids Phe, Tyr, and Trp and the cationic amino acids Arg and Lys. Our findings reveal that π-π interactions, while energetically favorable, are less abundant in structured proteins than commonly assumed and are often overshadowed by previously underappreciated, yet prevalent, CH-π interactions. Cation-π interactions, particularly those involving Arg, show strong binding energies and a specific geometric preference toward stacked conformations, despite the global QM minimum, suggesting that a rather perpendicular T-shape conformation should be more favorable. Our results support a more nuanced understanding of protein stabilization via interactions involving aromatic residues. On the one hand, our results challenge the traditional emphasis on π-π interactions in structured proteins by showing that CH-π and cation-π interactions contribute significantly to their structure. On the other hand, π-π interactions appear to be key stabilizers in solvated regions and thus may be particularly important to the stabilization of intrinsically disordered proteins.


Asunto(s)
Aminoácidos Aromáticos , Cationes , Proteínas , Teoría Cuántica , Proteínas/química , Aminoácidos Aromáticos/química , Cationes/química , Termodinámica , Modelos Moleculares , Conformación Proteica
11.
Nat Commun ; 15(1): 7901, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256374

RESUMEN

Poly(ADP-ribose) (PAR), a non-canonical nucleic acid, is essential for DNA/RNA metabolism and protein condensation, and its dysregulation is linked to cancer and neurodegeneration. However, key structural insights into PAR's functions remain largely uncharacterized, hindered by the challenges in synthesizing and characterizing PAR, which are attributed to its length heterogeneity. A central issue is how PAR, comprised solely of ADP-ribose units, attains specificity in its binding and condensing proteins based on chain length. Here, we integrate molecular dynamics simulations with small-angle X-ray scattering to analyze PAR structures. We identify diverse structural ensembles of PAR that fall into distinct subclasses and reveal distinct compaction of two different lengths of PAR upon the addition of small amounts of Mg2+ ions. Unlike PAR15, PAR22 forms ADP-ribose bundles via local intramolecular coil-to-globule transitions. Understanding these length-dependent structural changes could be central to deciphering the specific biological functions of PAR.


Asunto(s)
Simulación de Dinámica Molecular , Poli Adenosina Difosfato Ribosa , Dispersión del Ángulo Pequeño , Poli Adenosina Difosfato Ribosa/metabolismo , Poli Adenosina Difosfato Ribosa/química , Magnesio/química , Cationes/química , Difracción de Rayos X , Humanos
12.
Commun Biol ; 7(1): 1148, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39278937

RESUMEN

The formation of nuclear biomolecular condensates is often associated with local accumulation of proteins at a site of DNA damage. The key role in the formation of DNA repair foci belongs to PARP1, which is a sensor of DNA damage and catalyzes the synthesis of poly(ADP-ribose) attracting repair factors. We show here that biogenic cations such as Mg2+, Ca2+, Mn2+, spermidine3+, or spermine4+ can induce liquid-like assembly of poly(ADP-ribosyl)ated [PARylated] PARP1 into multimolecular associates (hereafter: self-assembly). The self-assembly of PARylated PARP1 affects the level of its automodification and hydrolysis of poly(ADP-ribose) by poly(ADP-ribose) glycohydrolase (PARG). Furthermore, association of PARylated PARP1 with repair proteins strongly stimulates strand displacement DNA synthesis by DNA polymerase ß (Pol ß) but has no noticeable effect on DNA ligase III activity. Thus, liquid-like self-assembly of PARylated PARP1 may play a critical part in the regulation of i) its own activity, ii) PARG-dependent hydrolysis of poly(ADP-ribose), and iii) Pol ß-mediated DNA synthesis. The latter can be considered an additional factor influencing the choice between long-patch and short-patch DNA synthesis during repair.


Asunto(s)
Poli(ADP-Ribosa) Polimerasa-1 , Poli ADP Ribosilación , Poli(ADP-Ribosa) Polimerasa-1/metabolismo , Poli(ADP-Ribosa) Polimerasa-1/genética , Humanos , Poli Adenosina Difosfato Ribosa/metabolismo , Glicósido Hidrolasas/metabolismo , Glicósido Hidrolasas/genética , Cationes Bivalentes/metabolismo , Reparación del ADN , ADN Polimerasa beta/metabolismo , Cationes/metabolismo , Daño del ADN
13.
Top Curr Chem (Cham) ; 382(3): 29, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39237745

RESUMEN

This review provides an in-depth examination of recent progress in the development of chemosensors, with a particular emphasis on colorimetric and fluorescent probes. It systematically explores various sensing mechanisms, including metal-to-ligand charge transfer (MLCT), ligand-to-metal charge transfer (LMCT), photoinduced electron transfer (PET), intramolecular charge transfer (ICT), and fluorescence resonance energy transfer (FRET), and elucidates the mechanism of action for cation and anion chemosensors. Special attention is given to phenothiazine-based fluorescence probes, highlighting their exceptional sensitivity and rapid detection abilities for a broad spectrum of analytes, including cations, anions, and small molecules. Phenothiazine chemosensors have emerged as versatile tools widely employed in a multitude of applications, spanning environmental and biomedical fields. Furthermore, it addresses existing challenges and offers insights into future research directions, aiming to facilitate the continued advancement of phenothiazine-based fluorescent probes.


Asunto(s)
Aniones , Cationes , Colorantes Fluorescentes , Fenotiazinas , Fenotiazinas/química , Colorantes Fluorescentes/química , Aniones/análisis , Aniones/química , Cationes/análisis , Cationes/química , Colorimetría , Transferencia Resonante de Energía de Fluorescencia
14.
Int J Mol Sci ; 25(17)2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39273279

RESUMEN

The rapid detection of contaminants in water resources is vital for safeguarding the environment, where the use of eco-friendly materials for water monitoring technologies has become increasingly prioritized. In this context, the role of biocomposites in the development of a SERS sensor is reported in this study. Grafted chitosan was employed as a matrix support for Ag nanoparticles (NPs) for the surface-enhanced Raman spectroscopy (SERS). Chitosan (CS) was decorated with thiol and carboxylic acid groups by incorporating S-acetyl mercaptosuccinic anhydride (SAMSA) to yield CS-SAMSA. Then, Ag NPs were immobilized onto the CS-SAMSA (Ag@CS-SAMSA) and characterized by spectral methods (IR, Raman, NIR, solid state 13C NMR with CP-MAS, XPS, and TEM). Ag@CS-SAMSA was evaluated as a substrate for SERS, where methylene blue (MB) was used as a model dye adsorbate. The Ag@CS-SAMSA sensor demonstrated a high sensitivity (with an enhancement factor ca. 108) and reusability over three cycles, with acceptable reproducibility and storage stability. The Raman imaging revealed a large SERS effect, whereas the MB detection varied from 1-100 µM. The limits of detection (LOD) and quantitation (LOQ) of the biocomposite sensor were characterized, revealing properties that rival current state-of-the-art systems. The dye adsorption profiles were studied via SERS by fitting the isotherm results with the Hill model to yield the ΔG°ads for the adsorption process. This research demonstrates a sustainable dual-function biocomposite with tailored adsorption and sensing properties suitable for potential utility in advanced water treatment technology and environmental monitoring applications.


Asunto(s)
Quitosano , Nanopartículas del Metal , Plata , Espectrometría Raman , Quitosano/química , Espectrometría Raman/métodos , Plata/química , Nanopartículas del Metal/química , Límite de Detección , Colorantes/química , Colorantes/análisis , Cationes/análisis , Contaminantes Químicos del Agua/análisis , Azul de Metileno/química
15.
J Mater Chem B ; 12(36): 8952-8965, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39171401

RESUMEN

Targeted and efficient gene delivery systems hold tremendous potential for the improvement of cancer therapy by enabling appropriate modification of biological processes. Herein, we report the design and synthesis of a novel cationic di-block copolypeptide, incorporating homoarginine (HAG) and shikimoyl (LSA) functionalities (HDA-b-PHAGm-b-PLSAn), tailored for enhanced gene transfection specifically in cancer cells. The di-block copolypeptide was synthesized via sequential N-carboxyanhydride (NCA) ring-opening polymerization (ROP) techniques and its physicochemical properties were characterized, including molecular weight, dispersity, secondary conformation, size, morphology, and surface charge. In contrast to the cationic poly-L-homoarginine, we observed a significantly reduced cytotoxic effect of this di-block copolypeptide due to the inclusion of the shikimoyl glyco-polypeptide block, which also added selectivity in internalizing particular cells. This di-block copolypeptide was internalized via mannose-receptor-mediated endocytosis, which was investigated by competitive receptor blocking with mannan. We evaluated the transfection efficiency of the copolypeptide in HEK 293T (noncancerous cells), MDA-MB-231 (breast cancer cells), and RAW 264.7 (dendritic cells) and compared it with commonly employed transfection agents (Lipofectamine). Our findings demonstrate that the homoarginine and shikimoyl-functionalized cationic di-block copolypeptide exhibits potent gene transfection capabilities with minimal cytotoxic effects, particularly in cancer cells, while it is ineffective for normal cells, indicative of its potential as a promising platform for cancer cell-specific gene delivery systems. To evaluate this, we delivered an artificially designed miRNA-plasmid against Hsp90 (amiR-Hsp90) which upon successful transfection depleted the Hsp90 (a chaperone protein responsible for tumour growth) level specifically in cancerous cells and enforced apoptosis. This innovative approach offers a new avenue for the development of targeted therapeutics with an improved efficacy and safety profile in cancer treatment.


Asunto(s)
Péptidos , Transfección , Humanos , Péptidos/química , Péptidos/farmacología , Péptidos/síntesis química , Cationes/química , Células HEK293 , Ratones , Animales , Tamaño de la Partícula , Estructura Molecular , Supervivencia Celular/efectos de los fármacos , Diseño de Fármacos , Línea Celular Tumoral
16.
J Org Chem ; 89(17): 12547-12558, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39137335

RESUMEN

Synthesis of an antigenic tetrasaccharide repeating unit of the O-polysaccharide of Salmonella enteritidis lipopolysaccharide has been accomplished. Those four monosaccharides were assembled stereoselectively by employing our recently developed cationic gold(I)-catalyzed glycosylation methodology involving various glycosyl N-1,1-dimethylpropargyl carbamate donors. The newly formed α-anomeric stereochemical configuration was controlled by the axial C2-OBz of the glycosyl donors via anchimeric assistance.


Asunto(s)
Carbamatos , Oro , Oligosacáridos , Salmonella enteritidis , Oro/química , Glicosilación , Carbamatos/química , Salmonella enteritidis/química , Catálisis , Oligosacáridos/química , Oligosacáridos/síntesis química , Cationes/química , Antígenos O/química , Estereoisomerismo
17.
Sci Rep ; 14(1): 19423, 2024 08 21.
Artículo en Inglés | MEDLINE | ID: mdl-39169091

RESUMEN

Wastewater from the food industry is considered harmful to human health and aquatic life, as well as polluting water and soil. This research is centered around finding an affordable and easy physicochemical method for dealing with waste generated by the food industry. To accomplish this goal, a new bio-based flocculant called 4-benzyl-4-(2-oleamidoethylamino-2-oxoethyl) morpholin-4-ium chloride was created using sustainable sources, specifically crude olive pomace oil. Its chemical structure was confirmed using various spectroscopic techniques such as FTIR, 1H-NMR, mass spectra, and 13C-NMR. This new bio-based cationic flocculant was combined with alum to act as a coagulant in the waste treatment process. Also, a study was conducted to determine the optimal conditions for the coagulation-flocculation process parameters, namely, pH and alum dosage, on COD and removal efficiency. The results showed that the optimal conditions for flocculation were achieved at pH 5.8, with 680 mg/L alum and 10 mg/L of commercial flocculant dose compared to only 5 mg/L of a new bio-based cationic flocculant. A comparison was made between the new bio-cationic flocculant and a commercial CTAB one for treating wastewater in the food industry. The study found that the new bio-based cationic flocculant was more effective in reducing the chemical oxygen demand, achieving a reduction of 61.3% compared to 54.6% for using a commercial cationic flocculant. Furthermore, using a new bio-based cationic flocculant costs only 0.49 $/g, which is less than the present cationic flocculant, which costs 0.93 $/g. The adoption of this new flocculant provides a sustainable alternative to existing industrial wastewater treatment processes.


Asunto(s)
Cationes , Floculación , Industria de Alimentos , Aguas Residuales , Aguas Residuales/química , Cationes/química , Purificación del Agua/métodos , Compuestos de Alumbre/química , Eliminación de Residuos Líquidos/métodos , Residuos Industriales , Concentración de Iones de Hidrógeno
18.
Food Chem ; 460(Pt 2): 140674, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39089025

RESUMEN

Citrus oil (CO) is a commonly used natural flavor with high volatility, which is not conducive to sustained release under food environmental stress. This study constructed novel ß-cyclodextrin/cationic cellulose nanocrystal (ß-CD/C-CNC) complexes via noncovalent interaction, which were used to stabilize CO-loaded Pickering emulsions (PEß-CD/C-CNC). The C-CNC greatly improved the physical stability, droplet dispersion and viscoelasticity of PEß-CD/C-CNC by forming a tight network structure, as verified by rheological behavior. Moreover, C-CNC improved the wettability of ß-CD/C-CNC complexes and enhanced the interaction between adjacent ß-CD/C-CNC complexes. C-CNC also contributed to the interfacial viscoelasticity, hydrated mass, and layer thickness via the interfacial dilational modulus and QCM-D. ß-CD/C-CNC complexes adsorbed on the oil-water interface gave rise to a dense filling layer as a physical barrier, enhancing the sustained-release performance of PEß-CD/C-CNC by limiting diffusion of citrus essential oil into the headspace. This study provides new technical approaches for aroma retention in the food industry.


Asunto(s)
Celulosa , Citrus , Preparaciones de Acción Retardada , Emulsiones , Aceites Volátiles , beta-Ciclodextrinas , Emulsiones/química , Citrus/química , beta-Ciclodextrinas/química , Celulosa/química , Aceites Volátiles/química , Preparaciones de Acción Retardada/química , Reología , Viscosidad , Cationes/química , Nanopartículas/química
19.
Microbiol Spectr ; 12(9): e0409723, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39101823

RESUMEN

Infection control measures to prevent viral and bacterial infection spread are critical to maintaining a healthy environment. Pathogens such as viruses and pyogenic bacteria can cause infectious complications. Viruses such as SARS-CoV-2 are known to spread through the aerosol route and on fomite surfaces, lasting for a prolonged time in the environment. Developing technologies to mitigate the spread of pathogens through airborne routes and on surfaces is critical, especially for patients at high risk for infectious complications. Multifunctional coatings with a broad capacity to bind pathogens that result in inactivation can disrupt infectious spread through aerosol and inanimate surface spread. This study uses C-POLAR, a proprietary cationic, polyamine, organic polymer with a charged, dielectric property coated onto air filtration material and textiles. Using both SARS-CoV-2 live viral particles and bovine coronavirus models, C-POLAR-treated material shows a dramatic 2-log reduction in circulating viral inoculum. This reduction is consistent in a static room model, indicating simple airflow through a static C-POLAR hanging can capture significant airborne particles. Finally, Gram-positive and Gram-negative bacteria are applied to C-POLAR textiles using a viability indicator to demonstrate eradication on fomite surfaces. These data suggest that a cationic polymer surface can capture and eradicate human pathogens, potentially interrupting the infectious spread for a more resilient environment. IMPORTANCE: Infection control is critical for maintaining a healthy home, work, and hospital environment. We test a cationic polymer capable of capturing and eradicating viral and bacterial pathogens by applying the polymer to the air filtration material and textiles. The data suggest that the simple addition of cationic material can result in the improvement of an infectious resilient environment against viral and bacterial pathogens.


Asunto(s)
COVID-19 , Cationes , Polímeros , SARS-CoV-2 , SARS-CoV-2/efectos de los fármacos , Polímeros/farmacología , Polímeros/química , Humanos , Animales , COVID-19/prevención & control , Cationes/química , Cationes/farmacología , Bovinos , Textiles/microbiología , Textiles/virología , Coronavirus Bovino/efectos de los fármacos , Fómites/microbiología , Fómites/virología , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Aerosoles , Bacterias Gramnegativas/efectos de los fármacos
20.
Chemosphere ; 364: 143106, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39153530

RESUMEN

Concurrent heavy metals remediation in natural environments poses significant challenges due to factors like metal speciation and interactions with soil moisture. This review focuses on strategies for immobilizing both anionic and cationic metals simultaneously in soil-crop systems. Key approaches include water management, biochar utilization, stabilizing agents, nanotechnology, fertilization, and bioremediation. Sprinkler or intermittent irrigation combined with soil amendments/biochar effectively immobilizes As/Cd/Pb simultaneously. This immobilization occurs through continuous adsorption-desorption, oxidation-reduction, and precipitation mechanisms influenced by soil pH, redox reactions, and Fe-oxides. Biochar from sources like wine lees, sewage sludge, spent coffee, and Fe-nanoparticles can immobilize As/Cd/Pb/Cr/Co/Cu/Zn together via precipitation. In addition, biochar from rice, wheat, corn straw, rice husk, sawdust, and wood chips, modified with chemicals or nanoparticles, simultaneously immobilizes As and Cd, containing higher Fe3O4, Fe-oxide, and OH groups. Ligand exchange immobilizes As, while ion exchange immobilizes Cd. Furthermore, combining biochar especially with iron, hydroxyapatite, magnetite, goethite, silicon, graphene, alginate, compost, and microbes-can achieve simultaneous immobilization. Other effective amendments are selenium fertilizer, Ge-nanocomposites, Fe-Si materials, ash, hormone, and sterilization. Notably, combining nano-biochar with microbes and/or fertilizers with Fe-containing higher adsorption sites, metal-binding cores, and maintaining a neutral pH could stimulate simultaneous immobilization. The amendments have a positive impact on soil physio-chemical improvement and crop development. Crops enhance production of growth metabolites, hormones, and xylem tissue thickening, forming a protective barrier by root Fe-plaque containing higher Fe-oxide, restricting upward metal movement. Therefore, a holistic immobilization mechanism reduces plant oxidative damage, improves soil and crop quality, and reduces food contamination.


Asunto(s)
Agricultura , Carbón Orgánico , Restauración y Remediación Ambiental , Metaloides , Metales Pesados , Contaminantes del Suelo , Contaminantes del Suelo/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo , Agricultura/métodos , Carbón Orgánico/química , Metaloides/química , Metales Pesados/química , Restauración y Remediación Ambiental/métodos , Suelo/química , Cationes/química , Aniones/química , Adsorción , Metales/química
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