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1.
Molecules ; 26(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361550

RESUMO

Efficient use of herbicides for plant protection requires the application of auxiliary substances such as surfactants, stabilizers, wetting or anti-foaming agents, and absorption enhancers, which can be more problematic for environment than the herbicides themselves. We hypothesized that the combination of sulfonylurea (iodosulfuron-methyl) anion with inexpensive, commercially available quaternary tetraalkylammonium cations could lead to biologically active ionic liquids (ILs) that could become a convenient and environment-friendly alternative to adjuvants. A simple one-step synthesis allowed for synthesizing iodosulfuron-methyl based ILs with high yields ranging from 88 to 96% as confirmed by UV, FTIR, and NMR. The obtained ILs were found to possess several favorable properties compared to the currently used sodium salt iodosulfuron-methyl, such as adjustable hydrophobicity (octanol-water partition coefficient) and enhanced stability in aqueous solutions, which was supported by molecular calculations showing cation-anion interaction energies. In addition, soil mobility and volatility of ILs were more beneficial compared to the parental herbicide. Herbicidal activity tests toward oil-seed rape and cornflower revealed that ILs comprising at least one alkyl chain in the decyl to octadecyl range had similar or better efficacy compared to the commercial preparation without addition of any adjuvant. Furthermore, results of antimicrobial activity indicated that they were practically harmless or slightly toxic toward model soil microorganisms such as Pseudomonas putida and Bacillus cereus.


Assuntos
Anti-Infecciosos/química , Herbicidas/química , Líquidos Iônicos/química , Sulfonamidas/química , Compostos de Sulfonilureia/química , Tensoativos/química , Anti-Infecciosos/farmacologia , Bacillus cereus/crescimento & desenvolvimento , Herbicidas/farmacologia , Pseudomonas putida/crescimento & desenvolvimento , Compostos de Sulfonilureia/farmacologia
2.
Molecules ; 26(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34361859

RESUMO

The removal of graffiti or over-painting requires special attention in order to not induce the surface destruction but to also address all of the important eco-compatibility concerns. Because of the necessity to avoid the use of volatile and toxic petroleum-based solvents that are common in cleaning formulations, much attention has recently been paid to the design of a variety of sustainable formulations that are based on biodegradable raw materials. In the present contribution we propose a new approach to graffiti cleaning formulations that are composed of newly synthesized green solvents such as esterified plant oils, i.e., rapeseed oil (RO), sunflower oil (SO), or used cooking oil (UCO), ethyl lactate (EL), and alkylpolyglucosides (APGs) as surfactants. Oil PEG-8 ester solvents were synthesized through the direct esterification/transesterification of these oils using monobutyltin(IV) tris(2-ethylhexanoate) and titanium(IV) butoxide catalysts under mild process conditions. The most efficient formulations, determined by optimization through the response surface methodology (RSM) was more effective in comparison to the reference solvents such as the so-called Nitro solvent (denoting a mixture of toluene and acetone) and petroleum ether. Additionally, the optimal product was found to be effective in removing graffiti from glass, metal, or sandstone surfaces under open-field conditions in the city of Wroclaw. The performed studies could be an invaluable tool for developing future green formulations for graffiti removal.


Assuntos
Corantes/química , Óleos Vegetais/química , Solventes/química , Tensoativos/química , Esterificação
3.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443601

RESUMO

Surfactant aggregates have long been considered as a tool to improve drug delivery and have been widely used in medical products. The pH-responsive aggregation behavior in anionic gemini surfactant 1,3-bis(N-dodecyl-N-propanesulfonate sodium)-propane (C12C3C12(SO3)2) and its mixture with a cationic monomeric surfactant cetyltrimethylammonium bromide (CTAB) have been investigated. The spherical-to-wormlike micelle transition was successfully realized in C12C3C12(SO3)2 through decreasing the pH, while the rheological properties were perfectly enhanced for the formation of wormlike micelles. Especially at 140 mM and pH 6.7, the mixture showed high viscoelasticity, and the maximum of the zero-shear viscosity reached 1530 Pa·s. Acting as a sulfobetaine zwitterionic gemini surfactant, the electrostatic attraction, the hydrogen bond and the short spacer of C12C3C12(SO3)2 molecules were all responsible for the significant micellar growth. Upon adding CTAB, the similar transition could also be realized at a low pH, and the further transformation to branched micelles occurred by adjusting the total concentration. Although the mixtures did not approach the viscosity maximum appearing in the C12C3C12(SO3)2 solution, CTAB addition is more favorable for viscosity enhancement in the wormlike-micelle region. The weakened charges of the headgroups in a catanionic mixed system minimizes the micellar spontaneous curvature and enhances the intermolecular hydrogen-bonding interaction between C12C3C12(SO3)2, facilitating the formation of a viscous solution, which would greatly induce entanglement and even the fusion of wormlike micelles, thus resulting in branched microstructures and a decline of viscosity.


Assuntos
Reologia , Tensoativos/química , Cetrimônio/química , Glutamatos/química , Concentração de Íons de Hidrogênio , Micelas , Viscosidade
4.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360724

RESUMO

The formation of coffee-ring deposits upon evaporation of sessile droplets containing mixtures of poly(diallyldimethylammonium chloride) (PDADMAC) and two different anionic surfactants were studied. This process is driven by the Marangoni stresses resulting from the formation of surface-active polyelectrolyte-surfactant complexes in solution and the salt arising from the release of counterions. The morphologies of the deposits appear to be dependent on the surfactant concentration, independent of their chemical nature, and consist of a peripheral coffee ring composed of PDADMAC and PDADMAC-surfactant complexes, and a secondary region of dendrite-like structures of pure NaCl at the interior of the residue formed at the end of the evaporation. This is compatible with a hydrodynamic flow associated with the Marangoni stress from the apex of the drop to the three-phase contact line for those cases in which the concentration of the complexes dominates the surface tension, whereas it is reversed when most of the PDADMAC and the complexes have been deposited at the rim and the bulk contains mainly salt.


Assuntos
Polieletrólitos/química , Polietilenos/química , Compostos de Amônio Quaternário/química , Silício/química , Tensoativos/química , Tensão Superficial
5.
Int J Mol Sci ; 22(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34360806

RESUMO

Surfactants are molecules that lower surface or interfacial tension, and thus they are broadly used as detergents, wetting agents, emulsifiers, foaming agents, or dispersants. However, for modern applications, substances that can perform more than one function are desired. In this study we evaluated antioxidant properties of two homological series of N-oxide surfactants: monocephalic 3-(alkanoylamino)propyldimethylamine-N-oxides and dicephalic N,N-bis[3,3'-(dimethylamino)propyl]alkylamide di-N-oxides. Their antiradical properties were tested against stable radicals using electron paramagnetic resonance (EPR) and UV-vis spectroscopy. The experimental investigation was supported by theoretical density functional theory (DFT) and ab initio modeling of the X-H bonds dissociation enthalpies, ionization potentials, and Gibbs free energies for radical scavenging reactions. The evaluation was supplemented with a study of biological activity. We found that the mono- and di-N-oxides are capable of scavenging reactive radicals; however, the dicephalic surfactants are more efficient than their linear analogues.


Assuntos
Sequestradores de Radicais Livres/química , Tensoativos/química , Espectroscopia de Ressonância de Spin Eletrônica
6.
Int J Mol Sci ; 22(16)2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34445500

RESUMO

Cationic surfactants interact with DNA (Deoxyribonucleic acid), forming surfactant-DNA complexes that offer particularly efficient control for encapsulation and release of DNA from DNA gel particles. In the present work, DNA-based particles were prepared using CTAB (Cetyltrimethylammonium bromide) as the cationic surfactant and modified using two different additives: (Multi-Walled Carbon Nanotubes) MWNT or PEG (Poly Ethylene Glycol). The use of both additives to form composites increased the stability of the gel particles. The stability was monitored by the release of DNA and CTAB in different pH solutions. However, not much is known about the influence of pH on DNA-surfactant interaction and the release of DNA and surfactant from gel particles. It was observed that the solubilization of DNA occurs only in very acid media, while that of CTAB does not depend on pH and gets to a plateau after about 8 h. Within 2 h in contact with a pH = 2 solution, about 1% DNA and CTAB was released. Complete destruction for the gel particles was observed in pH = 2 solution after 17 days for PEG and 20 days for MWNT. The composite particles show a considerably enlarged sustained release span compared to the unmodified ones. The dehydration-rehydration studies show that the structure of the composite gel particles, as determined from SAXS (Small-Angle-X-Ray-Scattering) experiments, is similar to that of the unmodified ones. These studies will allow a better knowledge of these particles' formation and evolution in view of possible applications in drug delivery and release.


Assuntos
Cetrimônio/química , DNA/química , Nanotubos de Carbono/química , Tensoativos/química , Géis , Concentração de Íons de Hidrogênio , Polietilenoglicóis , Espalhamento a Baixo Ângulo , Difração de Raios X
7.
J Chromatogr A ; 1652: 462353, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34237484

RESUMO

Poloxamer 188 (P188) is formulated in proteinaceous therapeutics as an alternative surfactant to polysorbate because of its good chemical stability and surfactant properties, which enable interfacial protection, preventing visible and sub-visible particle formation. However, due to the nature of polymer heterogeneity and limited analytical approaches to resolve the superimposed components of P188, the impact of its quality variance on protein stability is still not well understood. In this study, we developed an analytical method to evaluate the components of P188 as a function of the length of polypropylene oxide (PPO), by maintaining polyethylene oxide (PEO) at the critical point of adsorption (CPA) to eliminate its chromatographic interference. The effectiveness of the separation was confirmed by nuclear magnetic resonance (NMR) spectroscopy and mass spectroscopy (MS) of the individual fractions corresponding to each peak. Additionally, a design of experiments (DoE) and method qualification were carried out to identify and optimize the key operation parameters, including column temperature and evaporative light scattering detector (ELSD) settings that need to be strictly controlled for reliable analytical results. In conclusion, this method is sensitive and reliable to compare the quality variance of commercial P188 and is suitable for routine quality control purposes. The application of this method could help in further understanding the Critical Material Attributes (CMA) that may affect the quality attributes of proteins in formulations.


Assuntos
Cromatografia Líquida/métodos , Poloxâmero/química , Tensoativos/química , Adsorção , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Poloxâmero/isolamento & purificação , Polietilenoglicóis/química , Polímeros/química , Propilenoglicóis/química , Proteínas/uso terapêutico , Tensoativos/isolamento & purificação
8.
J Biol Chem ; 297(2): 100940, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34237302

RESUMO

The severe acute respiratory syndrome coronavirus 2 envelope protein (S2-E) is a conserved membrane protein that is important for coronavirus (CoV) assembly and budding. Here, we describe the recombinant expression and purification of S2-E in amphipol-class amphipathic polymer solutions, which solubilize and stabilize membrane proteins, but do not disrupt membranes. We found that amphipol delivery of S2-E to preformed planar bilayers results in spontaneous membrane integration and formation of viroporin cation channels. Amphipol delivery of the S2-E protein to human cells results in plasma membrane integration, followed by retrograde trafficking to the trans-Golgi network and accumulation in swollen perinuclear lysosomal-associated membrane protein 1-positive vesicles, likely lysosomes. CoV envelope proteins have previously been proposed to manipulate the luminal pH of the trans-Golgi network, which serves as an accumulation station for progeny CoV particles prior to cellular egress via lysosomes. Delivery of S2-E to cells will enable chemical biological approaches for future studies of severe acute respiratory syndrome coronavirus 2 pathogenesis and possibly even development of "Trojan horse" antiviral therapies. Finally, this work also establishes a paradigm for amphipol-mediated delivery of membrane proteins to cells.


Assuntos
Membrana Celular/efeitos dos fármacos , Proteínas do Envelope de Coronavírus/metabolismo , Polímeros/farmacologia , Propilaminas/farmacologia , Tensoativos/farmacologia , Rede trans-Golgi/metabolismo , Membrana Celular/metabolismo , Proteínas do Envelope de Coronavírus/genética , Células HeLa , Humanos , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Lisossomos/metabolismo , Polímeros/química , Propilaminas/química , Transporte Proteico , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tensoativos/química
9.
J Am Chem Soc ; 143(31): 12315-12327, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34324336

RESUMO

Efficient viral or nonviral delivery of nucleic acids is the key step of genetic nanomedicine. Both viral and synthetic vectors have been successfully employed for genetic delivery with recent examples being DNA, adenoviral, and mRNA-based Covid-19 vaccines. Viral vectors can be target specific and very efficient but can also mediate severe immune response, cell toxicity, and mutations. Four-component lipid nanoparticles (LNPs) containing ionizable lipids, phospholipids, cholesterol for mechanical properties, and PEG-conjugated lipid for stability represent the current leading nonviral vectors for mRNA. However, the segregation of the neutral ionizable lipid as droplets in the core of the LNP, the "PEG dilemma", and the stability at only very low temperatures limit their efficiency. Here, we report the development of a one-component multifunctional ionizable amphiphilic Janus dendrimer (IAJD) delivery system for mRNA that exhibits high activity at a low concentration of ionizable amines organized in a sequence-defined arrangement. Six libraries containing 54 sequence-defined IAJDs were synthesized by an accelerated modular-orthogonal methodology and coassembled with mRNA into dendrimersome nanoparticles (DNPs) by a simple injection method rather than by the complex microfluidic technology often used for LNPs. Forty four (81%) showed activity in vitro and 31 (57%) in vivo. Some, exhibiting organ specificity, are stable at 5 °C and demonstrated higher transfection efficiency than positive control experiments in vitro and in vivo. Aside from practical applications, this proof of concept will help elucidate the mechanisms of packaging and release of mRNA from DNPs as a function of ionizable amine concentration, their sequence, and constitutional isomerism of IAJDs.


Assuntos
Dendrímeros/química , Portadores de Fármacos/química , Nanopartículas/química , RNA Mensageiro/metabolismo , Tensoativos/química , Animais , Dendrímeros/síntese química , Portadores de Fármacos/síntese química , Liberação Controlada de Fármacos , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Estudo de Prova de Conceito , Tensoativos/síntese química
10.
Molecules ; 26(14)2021 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-34299617

RESUMO

Oligomeric surfactants display the novel properties of low surface activity, low critical micellar concentration and enhanced viscosity, but no CO2 switchable oligomeric surfactants have been developed so far. The introduction of CO2 can convert tertiary amine reversibly to quaternary ammonium salt, which causes switchable surface activity. In this study, epoxidized soybean oil was selected as a raw material to synthesize a CO2-responsive oligomeric surfactant. After addition and removal of CO2, the conductivity analyzing proves that the oligomeric surfactant had a good response to CO2 stimulation. The viscosity of the oligomeric surfactant solution increased obviously after sparging CO2, but returned to its initial low viscosity in the absence of CO2. This work is expected to open a new window for the study of bio-based CO2-stimulated oligomeric surfactants.


Assuntos
Dióxido de Carbono/química , Óleo de Soja/química , Soja/química , Tensoativos/química , Aminas/química , Micelas , Compostos de Amônio Quaternário/química , Viscosidade , Água/química
11.
Int J Mol Sci ; 22(14)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34299196

RESUMO

The phenomenon of drag reduction (known as the "Toms effect") has many industrial and engineering applications, but a definitive molecular-level theory has not yet been constructed. This is due both to the multiscale nature of complex fluids and to the difficulty of directly observing self-assembled structures in nonequilibrium states. On the basis of a large-scale coarse-grained molecular simulation that we conducted, we propose a possible mechanism of turbulence suppression in surfactant aqueous solution. We demonstrate that maintaining sufficiently large micellar structures and a homogeneous radial distribution of surfactant molecules is necessary to obtain the drag-reduction effect. This is the first molecular-simulation evidence that a micellar structure is responsible for drag reduction in pipe flow, and should help in understanding the mechanisms underlying drag reduction by surfactant molecules under nonequilibrium conditions.


Assuntos
Tensoativos/química , Água/química , Simulação por Computador , Fricção , Micelas , Modelos Químicos , Simulação de Dinâmica Molecular , Fenômenos Físicos , Viscosidade
12.
Science ; 373(6554): 541-547, 2021 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-34326236

RESUMO

Repurposing drugs as treatments for COVID-19, the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has drawn much attention. Beginning with sigma receptor ligands and expanding to other drugs from screening in the field, we became concerned that phospholipidosis was a shared mechanism underlying the antiviral activity of many repurposed drugs. For all of the 23 cationic amphiphilic drugs we tested, including hydroxychloroquine, azithromycin, amiodarone, and four others already in clinical trials, phospholipidosis was monotonically correlated with antiviral efficacy. Conversely, drugs active against the same targets that did not induce phospholipidosis were not antiviral. Phospholipidosis depends on the physicochemical properties of drugs and does not reflect specific target-based activities-rather, it may be considered a toxic confound in early drug discovery. Early detection of phospholipidosis could eliminate these artifacts, enabling a focus on molecules with therapeutic potential.


Assuntos
Antivirais/farmacologia , COVID-19/tratamento farmacológico , Reposicionamento de Medicamentos , Lipidoses/induzido quimicamente , Fosfolipídeos/metabolismo , SARS-CoV-2/efeitos dos fármacos , Células A549 , Animais , Antivirais/química , Antivirais/uso terapêutico , Antivirais/toxicidade , COVID-19/virologia , Cátions , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Feminino , Humanos , Camundongos , Testes de Sensibilidade Microbiana , SARS-CoV-2/fisiologia , Tensoativos/química , Tensoativos/farmacologia , Tensoativos/toxicidade , Células Vero , Replicação Viral/efeitos dos fármacos
13.
Int J Mol Sci ; 22(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34204914

RESUMO

In this paper, we report the development of the novel self-assembling systems based on oppositely charged Pillar[5]arenes and surfactants for encapsulation of diagnostic dye DAPI. For this purpose, the aggregation behavior of synthesized macrocycles and surfactants in the presence of Pillar[5]arenes functionalized by carboxy and ammonium terminal groups was studied. It has been demonstrated that by varying the molar ratio in Pillar[5]arene-surfactant systems, it is possible to obtain various types of supramolecular systems: host-guest complexes at equimolar ratio of Pillar[5]arene-surfactant and interpolyelectrolyte complexes (IPECs) are self-assembled materials formed in aqueous medium by two oppositely charged polyelectrolytes (macrocycle and surfactant micelles). It has been suggested that interaction of Pillar[5]arenes with surfactants is predominantly driven by cooperative electrostatic interactions. Synthesized stoichiometric and non-stoichiometric IPECs specifically interact with DAPI. UV-vis, luminescent spectroscopy and molecular docking data show the structural feature of dye-loaded IPEC and key role of the electrostatic, π-π-stacking, cation-π interactions in their formation. Such a strategy for the design of supramolecular Pillar[5]arene-surfactant systems will lead to a synergistic interaction of the two components and will allow specific interaction with the third component (drug or fluorescent tag), which will certainly be in demand in pharmaceuticals and biomedical diagnostics.


Assuntos
Calixarenos/química , Indóis/química , Polieletrólitos/química , Tensoativos/química , Compostos de Amônio/química , Cátions/química , Micelas , Simulação de Acoplamento Molecular , Eletricidade Estática , Água/química
14.
Molecules ; 26(12)2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34208560

RESUMO

Pectis elongata is found in the northern and northeastern regions of Brazil. It is considered a lemongrass due to its citric scent. The remarkable citral content and the wide antimicrobial properties and bioactive features of this terpene make this essential oil (EO) eligible for several industrial purposes, especially in cosmetics and phytotherapics. However, to address the problems regarding citral solubility, nano-emulsification is considered a promising strategy thanks to its improved dispersability. Thus, in this paper we propose a low-energy approach for the development of citral-based nano-emulsions prepared with P. elongata EO. The plant was hydrodistillated to produce the EO, which was characterized with a gas chromatograph coupled to mass spectrometry. The nano-emulsion prepared by a non-heated water titrating (low-energy) method was composed of 5% (w/w) EO, 5% (w/w) non-ionic surfactants and 90% (w/w) deionized water and was analyzed by dynamic light scattering. Levels of citral of around 90% (neral:geranial-4:5) were detected in the EO and no major alteration in the ratio of citral was observed after the nano-emulsification. The nano-emulsion was stable until the 14th day (size around 115 nm and polydispersity index around 0.2) and no major alteration in droplet size was observed within 30 days of storage. Understanding the droplet size distribution as a function of time and correlating it to concepts of compositional ripening, as opposing forces to the conventional Ostwald ripening destabilization mechanism, may open interesting approaches for further industrial application of novel, low-energy, ecofriendly approaches to high citral essential oil-based nano-emulsions based on lemongrass plants.


Assuntos
Monoterpenos Acíclicos/isolamento & purificação , Emulsões/química , Óleos Voláteis/isolamento & purificação , Monoterpenos Acíclicos/química , Brasil , Cymbopogon/química , Cromatografia Gasosa-Espectrometria de Massas , Monoterpenos/química , Óleos Voláteis/química , Extratos Vegetais/isolamento & purificação , Tensoativos/química , Água/química
15.
Molecules ; 26(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201182

RESUMO

Most biosurfactants are obtained using costly culture media and purification processes, which limits their wider industrial use. Sustainability of their production processes can be achieved, in part, by using cheap substrates found among agricultural and food wastes or byproducts. In the present study, crude glycerol, a raw material obtained from several industrial processes, was evaluated as a potential low-cost carbon source to reduce the costs of surfactin production by Bacillus subtilis #309. The culture medium containing soap-derived waste glycerol led to the best surfactin production, reaching about 2.8 g/L. To the best of our knowledge, this is the first report describing surfactin production by B. subtilis using stearin and soap wastes as carbon sources. A complete chemical characterization of surfactin analogs produced from the different waste glycerol samples was performed by liquid chromatography-mass spectrometry (LC-MS) and Fourier transform infrared spectroscopy (FTIR). Furthermore, the surfactin produced in the study exhibited good stability in a wide range of pH, salinity and temperatures, suggesting its potential for several applications in biotechnology.


Assuntos
Bacillus subtilis/química , Glicerol/química , Tensoativos/química , Biotecnologia/métodos , Carbono/química , Cromatografia Líquida/métodos , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Espectrometria de Massas/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Temperatura
16.
Int J Mol Sci ; 22(14)2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34299121

RESUMO

In this work, we have developed a chemical procedure enabling the preparation of highly ordered and vertically aligned mesoporous silica films containing selected contents of silver ions bonded inside the mesopore channels via anchoring propyl-carboxyl units. The procedure involves the electrochemically assisted self-assembly co-condensation of tetraethoxysilane and (3-cyanopropyl)triethoxysilane in the presence of cetyltrimethylammonium bromide as a surfactant, the subsequent hydrolysis of cyano groups into carboxylate ones, followed by their complexation with silver ions. The output materials have been electrochemically characterized with regard to the synthesis effectiveness in order to confirm and quantify the presence of the silver ions in the material. The mesostructure has been observed by transmission electron microscopy. We have pointed out that it is possible to finely tune the functionalization level by controlling the co-condensation procedure, notably the concentration of (3-cyanopropyl)triethoxysilane in the synthesis medium.


Assuntos
Dióxido de Silício/síntese química , Prata/química , Tensoativos/química , Cetrimônio/química , Porosidade
17.
Photochem Photobiol Sci ; 20(7): 939-953, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34255302

RESUMO

A novel tricationic Zn(II)phthalocyanine derivative, (NCH3)3ZnPc3+, was synthesized by ring expansion reaction of boron(III) [2,9(10),16(17)-trinitrosubphthalocyaninato]chloride. First, the reaction of this subphthalocyanine with 2,3-naphthalenedicarbonitrile and Zn(CH3COO)2 catalyzed by 8-diazabicyclo[5.4.0]undec-7-ene was used to obtain the A3B-type nitrophthalocyanine. After reduction of nitro groups with Na2S and exhaustive methylation of amino groups, (NCH3)3ZnPc3+ was formed in good yields. In addition, the tetracationic analog (NCH3)4ZnPc4+ was synthesized to compare their properties. The absorption and fluorescence spectra showed the Q-bands and the red emission, respectively, which are characteristic of the Zn(II)phthalocyanine derivatives in N,N-dimethylformamide. Furthermore, photodynamic activity sensitized by these compounds was studied in the presence of different molecular probes to sense the formation of reactive oxygen species. (NCH3)3ZnPc3+ efficiently produced singlet molecular oxygen and also it sensitized the formation of superoxide anion radical in the presence of NADH, while the photodynamic activity of (NCH3)4ZnPc4+ was very poor, possibly due to the partial formation of aggregates. Furthermore, the decomposition of L-tryptophan induced by (NCH3)3ZnPc3+ was mainly mediated by a type II mechanism. Antimicrobial photodynamic inactivation sensitized by these phthalocyanines was evaluated in Staphylococcus aureus, Escherichia coli, and Candida albicans, as representative microbial cells. In cell suspensions, (NCH3)3ZnPc3+ was rapidly bound to microbial cells, showing bioimages with red fluorescence emission. After 5 min of irradiation with visible light, (NCH3)3ZnPc3+ was able to completely eliminate S. aureus, E. coli and C. albicans, using 1.0, 2.5 and 5.0 µM phthalocyanine, respectively. In contrast, a low photoinactivation activity was found with (NCH3)4ZnPc4+ as a photosensitizer. Therefore, the amphiphilic tricationic phthalocyanine (NCH3)3ZnPc3+ is a promising photosensitizing structure for application as a broad-spectrum antimicrobial phototherapeutic agent.


Assuntos
Anti-Infecciosos/farmacologia , Indóis/farmacologia , Compostos Organometálicos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Tensoativos/farmacologia , Anti-Infecciosos/química , Candida albicans/efeitos dos fármacos , Cátions/química , Cátions/farmacologia , Escherichia coli/efeitos dos fármacos , Indóis/química , Testes de Sensibilidade Microbiana , Compostos Organometálicos/química , Fármacos Fotossensibilizantes/química , Staphylococcus aureus/efeitos dos fármacos , Tensoativos/química
18.
Int J Mol Sci ; 22(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299360

RESUMO

Nonviral vectors for gene therapy such as lipoplexes are characterized by low toxicity, high biocompatibility, and good transfection efficiency. Specifically, lipoplexes based on polymeric surfactants and phospholipids have great potential as gene carriers due to the increased ability to bind genetic material (multiplied positive electric charge) while lowering undesirable effects (the presence of lipids makes the system more like natural membranes). This study aimed to test the ability to bind and release genetic material by lipoplexes based on trimeric surfactants and lipid formulations of different compositions and to characterize formed complexes by circular dichroism (CD) spectroscopy and atomic force microscopy (AFM). The cytotoxicity of studied lipoplexes was tested on HeLa cells by the MTT cell viability assay and the dye exclusion test (trypan blue). The presence of lipids in the system lowered the surfactant concentration required for complexation (higher efficiency) and reduced the cytotoxicity of lipoplexes. Surfactant/lipids/DNA complexes were more stable than surfactant/DNA complexes. Surfactant molecules induced the genetic material condensation, but the presence of lipids significantly intensified this process. Systems based on trimeric surfactants and lipid formulations, particularly TRI_N and TRI_IMI systems, could be used as delivery carrier, and have proven to be highly effective, nontoxic, and universal for DNA of various lengths.


Assuntos
Vetores Genéticos/genética , Fosfolipídeos/química , Tensoativos/química , Linhagem Celular Tumoral , Dicroísmo Circular/métodos , DNA/química , Técnicas de Transferência de Genes , Células HeLa , Humanos , Lipídeos/química , Microscopia de Força Atômica/métodos
19.
Nat Commun ; 12(1): 4039, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34193867

RESUMO

The controlled assembly of nanomaterials into desired architectures presents many opportunities; however, current preparations lack spatial precision and versatility in developing complex nano-architectures. Inspired by the amphiphilic nature of surfactants, we develop a facile approach to guide nanomaterial integration - spatial organization and distribution - in metal-organic frameworks (MOFs). Named surfactant tunable spatial architecture (STAR), the technology leverages the varied interactions of surfactants with nanoparticles and MOF constituents, respectively, to direct nanoparticle arrangement while molding the growing framework. By surfactant matching, the approach achieves not only tunable and precise integration of diverse nanomaterials in different MOF structures, but also fast and aqueous synthesis, in solution and on solid substrates. Employing the approach, we develop a dual-probe STAR that comprises peripheral working probes and central reference probes to achieve differential responsiveness to biomarkers. When applied for the direct profiling of clinical ascites, STAR reveals glycosylation signatures of extracellular vesicles and differentiates cancer patient prognosis.


Assuntos
Biomarcadores Tumorais/metabolismo , Técnicas Biossensoriais/métodos , Neoplasias Colorretais/diagnóstico , Vesículas Extracelulares/metabolismo , Estruturas Metalorgânicas/química , Nanoestruturas/química , Tensoativos/química , Ascite/metabolismo , Neoplasias Colorretais/metabolismo , Glicosilação , Humanos , Prognóstico
20.
Phys Chem Chem Phys ; 23(24): 13724-13733, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34128514

RESUMO

Sequence-selective recognition of cationic amphipathic peptides by synthetic receptors is significant to biological applications, but it is still a great challenging task. Here we first study the binding characteristics of receptor cucurbit[7]uril (CB[7]) to the smallest aromatic tripeptides X1GG (X1 = tryptophan (W), phenylalanine (F), and tyrosine (Y)) and basic tripeptides X2GG (X2 = arginine (R), lysine (K), and histidine (H)) by molecular dynamics simulations. The study indicates that the sidechains of aromatic X1 residues can be encapsulated into the CB[7] cavity, while the sidechains of basic X2 residues prefer to locate at the CB[7] portal. Based on that, we consider hydrophobic aromatic residues as the N-terminus, the smallest glycine (G) as the 2nd-residue and basic residues as the C-terminus, and design nine tripeptides X1GX2 (X1 = F, Y, W and X2 = H, K, R). We found that there is a great influence of the C-terminal basic residue of X1GX2 on binding with CB[7] due to the introduction of a new binding site between CB[7] and the sidechain of the C-terminal residue. Interestingly, CB[7] can differentiate WGR and WGK with similar structures efficiently because of their eight orders of magnitude difference in the association constant (Ka). Besides, for WGR, YGR, and YGK with a nanomolar binding affinity (Ka > 109 M-1), on reversing the sequence order of the 2nd-residue and 3rd-residue, their Ka reduces by about at least 1000-fold, implying the sequence dependence of CB[7] on recognizing these tripeptides. These results predict the potential applications of CB[7] in recognizing cationic amphipathic peptides.


Assuntos
Hidrocarbonetos Aromáticos com Pontes/química , Imidazóis/química , Oligopeptídeos/química , Tensoativos/química , Cátions , Simulação de Dinâmica Molecular , Soluções , Água/química
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