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1.
Food Chem ; 451: 139469, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38703727

RESUMEN

Excipient selection is crucial to address the oxidation and solubility challenges of bioactive substances, impacting their safety and efficacy. AKPL, a novel ω-3 polyunsaturated fatty acids (PUFAs) esterified phospholipid derived from Antarctic krill, demonstrates unique antioxidant capabilities and synergistic effects. It exhibits pronounced surface activity and electronegativity at physiological pH, as evidenced by a critical micelle concentration (CMC) of 0.15 g/L and ζ-potential of -49.9 mV. In aqueous environments, AKPL self-assembles into liposomal structures, offering high biocompatibility and promoting cell proliferation. Its polyunsaturated bond-rich structure provides additional oxidation sites, imparting antioxidant properties superior to other phospholipids like DSPC and DOPC. Additionally, AKPL augments the efficacy of lipophilic antioxidants, such as alpha-tocopherol and curcumin, in aqueous media through both intermolecular and intramolecular interactions. In sum, AKPL emerges as an innovative unsaturated phospholipid, offering new strategies for encapsulating and delivering oxygen-sensitive agents.


Asunto(s)
Antioxidantes , Euphausiacea , Fosfolípidos , Euphausiacea/química , Animales , Fosfolípidos/química , Antioxidantes/química , Antioxidantes/farmacología , Coloides/química , Humanos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Regiones Antárticas , Ácidos Grasos Omega-3/química , Ácidos Grasos Omega-3/farmacología
2.
Biosens Bioelectron ; 259: 116396, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38772247

RESUMEN

Electrochemical biosensors hold promise for advanced analytical applications in modern life analysis due to their miniaturization and cost-effectiveness. Nevertheless, their implementation in complex biological systems necessitates overcoming challenges related to timeliness, sensitivity, and interference resistance. Here, we developed a novel DNA hydrogel three-dimensional electron transporter through liquid-colloid-solid assembly, integrating electronic mediators and employing porous electrode covers with 3D printing technology. Our approach facilitated the fabrication of a high-performance electrochemical sensor for small molecule detection, leveraging target-specific aptamers and catalytic hairpin assembly (CHA) elements within the DNA hydrogel, which exhibited outstanding selectivity, sensitivity, and universality, achieving detection limits of 0.047 nM for kanamycin and 2.67 pM for ATP. Furthermore, this sensor could detect kanamycin in real samples, demonstrating good accuracy and robust anti-interference capabilities in human serum. Our work not only possesses substantial application value in clinical sample analysis but also represents a breakthrough in traditional strategies, thereby contributing to advancements in the application of electrochemical biosensors for life analysis.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Kanamicina , Límite de Detección , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Humanos , Aptámeros de Nucleótidos/química , Kanamicina/análisis , Hidrogeles/química , ADN/química , Adenosina Trifosfato/análisis , Adenosina Trifosfato/sangre , Coloides/química , Impresión Tridimensional , Electrodos
3.
Food Chem ; 452: 139474, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38744126

RESUMEN

In order to prevent the photooxidation of phytosterols, a new type of Pickering emulsion was developed by regulating the oriented distribution of antioxidants in colloidal lipid particles (CLPs) at the oil-water interface. High-melting-point and low-melting-point lipids were tested to modulate their protective effect against phytosterols photooxidation. Results showed that CLPs could stabilize Pickering emulsion and encapsulate antioxidants, providing a dual functional delivery system for phytosterols protection. The Pickering emulsion formed had a particle size of around 350-820 nm, and the crystallization and melting temperatures of tripalmitin particles were approximately 32 °C and 63.8 °C, respectively. The addition of tributyrin or tricaprylin reduced the crystallization and melting temperatures of Pal CLPs and improved the photooxidation emulsion stability. The prepared Pickering emulsion remained stable for a maximum of 12 days under accelerated light-induced oxidation. Among all formulations, the emulsion primarily composed of tripalmitin CLPs, with added tributyrin and resveratrol, exhibited the highest photooxidation stability.


Asunto(s)
Antioxidantes , Emulsiones , Lípidos , Oxidación-Reducción , Tamaño de la Partícula , Fitosteroles , Emulsiones/química , Fitosteroles/química , Antioxidantes/química , Lípidos/química , Coloides/química , Luz , Composición de Medicamentos , Estabilidad de Medicamentos
4.
Int J Pharm ; 658: 124231, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38759741

RESUMEN

Two frequent problems hindering clinical translation of nanomedicine are low drug loading and low colloidal stability. Previous efforts to achieve ultrahigh drug loading (>30 %) introduce new hurdles, including lower colloidal stability and others, for clinical translation. Herein, we report a new class of drug nano-carriers based on our recent finding in protein-nanoparticle co-assembly supraparticle (PNCAS), with both ultrahigh drug loading (58 % for doxorubicin, i.e., DOX) and ultrahigh colloidal stability (no significant change in hydrodynamic size after one year). We further show that our PNCAS-based drug nano-carrier possesses a built-in environment-responsive drug release feature: once in lysosomes, the loaded drug molecules are released instantly (<1 min) and completely (∼100 %). Our PNCAS-based drug delivery system is spontaneously formed by simple mixing of hydrophobic nanoparticles, albumin and drugs. Several issues related to industrial production are studied. The ultrahigh drug loading and stability of DOX-loaded PNCAS enabled the delivery of an exceptionally high dose of DOX into a mouse model of breast cancer, yielding high efficacy and no observed toxicity. With further developments, our PNCAS-based delivery systems could serve as a platform technology to meet the multiple requirements of clinical translation of nanomedicines.


Asunto(s)
Doxorrubicina , Liberación de Fármacos , Lisosomas , Nanopartículas , Doxorrubicina/administración & dosificación , Doxorrubicina/química , Doxorrubicina/farmacocinética , Animales , Nanopartículas/química , Femenino , Portadores de Fármacos/química , Ratones , Coloides/química , Humanos , Sistemas de Liberación de Medicamentos , Ratones Endogámicos BALB C , Estabilidad de Medicamentos , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Línea Celular Tumoral , Neoplasias de la Mama/tratamiento farmacológico
5.
Int J Biol Macromol ; 270(Pt 1): 132208, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38723835

RESUMEN

Monoclonal antibodies (mAbs) have revolutionised the biopharmaceutical market. Being proteinaceous, mAbs are prone to chemical and physical instabilities. Various approaches were attempted to stabilise proteins against degradation factors. Ionic liquids (ILs) and deep eutectic solvents (DESs) have been established as green solvents for ever-increasing pharmaceutical and biopharmaceutical applications. Hence, amino acid (AA)-based ILs, were used for the first time, for mAb stabilisation. Choline (Ch)-based DESs were also utilised for comparison purposes. The prepared ILs and DESs were utilised to stabilise Atezolizumab (Amab, anti-PDL-1 mAb). The formulations of Amab in ILs and DESs were incubated at room temperature, 45 or 55 °C. Following this, the structural stability of Amab was appraised. Interestingly, Ch-Valine retained favourable structural stability of Amab with minimal detected aggregation or degradation as confirmed by UV-visible spectroscopy and protein Mass Spectroscopy. The measured hydrodynamic diameter of Amab in Ch-Valine ranged from 10.40 to 11.65 nm. More interestingly, the anticancer activity of Amab was evaluated, and Ch-Valine was found to be optimum in retaining the activity of Amab when compared to other formulations, including the control Amab sample. Collectively, this study has spotlighted the advantages of adopting the Ch-AA ILs for the structural and functional stabilising of mAbs.


Asunto(s)
Aminoácidos , Anticuerpos Monoclonales Humanizados , Antineoplásicos , Líquidos Iónicos , Líquidos Iónicos/química , Anticuerpos Monoclonales Humanizados/química , Anticuerpos Monoclonales Humanizados/farmacología , Humanos , Antineoplásicos/química , Antineoplásicos/farmacología , Aminoácidos/química , Coloides/química , Estabilidad de Medicamentos , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/farmacología , Estabilidad Proteica , Temperatura , Línea Celular Tumoral , Solventes/química
6.
Nature ; 628(8009): 771-775, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38632399

RESUMEN

Quantitative detection of various molecules at very low concentrations in complex mixtures has been the main objective in many fields of science and engineering, from the detection of cancer-causing mutagens and early disease markers to environmental pollutants and bioterror agents1-5. Moreover, technologies that can detect these analytes without external labels or modifications are extremely valuable and often preferred6. In this regard, surface-enhanced Raman spectroscopy can detect molecular species in complex mixtures on the basis only of their intrinsic and unique vibrational signatures7. However, the development of surface-enhanced Raman spectroscopy for this purpose has been challenging so far because of uncontrollable signal heterogeneity and poor reproducibility at low analyte concentrations8. Here, as a proof of concept, we show that, using digital (nano)colloid-enhanced Raman spectroscopy, reproducible quantification of a broad range of target molecules at very low concentrations can be routinely achieved with single-molecule counting, limited only by the Poisson noise of the measurement process. As metallic colloidal nanoparticles that enhance these vibrational signatures, including hydroxylamine-reduced-silver colloids, can be fabricated at large scale under routine conditions, we anticipate that digital (nano)colloid-enhanced Raman spectroscopy will become the technology of choice for the reliable and ultrasensitive detection of various analytes, including those of great importance for human health.


Asunto(s)
Coloides , Imagen Individual de Molécula , Espectrometría Raman , Coloides/química , Hidroxilamina/química , Nanopartículas del Metal/química , Distribución de Poisson , Prueba de Estudio Conceptual , Reproducibilidad de los Resultados , Plata/química , Imagen Individual de Molécula/métodos , Imagen Individual de Molécula/normas , Espectrometría Raman/métodos , Espectrometría Raman/normas , Vibración
7.
Nat Commun ; 15(1): 3603, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38684662

RESUMEN

The ability to sense chemical gradients and respond with directional motility and chemical activity is a defining feature of complex living systems. There is a strong interest among scientists to design synthetic systems that emulate these properties. Here, we realize and control such behaviors in a synthetic system by tailoring multivalent interactions of adenosine nucleotides with catalytic microbeads. We first show that multivalent interactions of the bead with gradients of adenosine mono-, di- and trinucleotides (AM/D/TP) control both the phoretic motion and a proton-transfer catalytic reaction, and find that both effects are diminished greatly with increasing valence of phosphates. We exploit this behavior by using enzymatic hydrolysis of ATP to AMP, which downregulates multivalent interactivity in situ. This produces a sudden increase in transport of the catalytic microbeads (a phoretic jump), which is accompanied by increased catalytic activity. Finally, we show how this enzymatic activity can be systematically tuned, leading to simultaneous in situ spatial and temporal control of the location of the microbeads, as well as the products of the reaction that they catalyze. These findings open up new avenues for utilizing multivalent interaction-mediated programming of complex chemo-mechanical behaviors into active systems.


Asunto(s)
Adenosina Trifosfato , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/química , Hidrólisis , Catálisis , Coloides/química , Microesferas , Adenosina Monofosfato/metabolismo , Adenosina Monofosfato/química , Adenosina/metabolismo , Adenosina/química
8.
J Colloid Interface Sci ; 667: 259-268, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38636227

RESUMEN

Indocyanine green (ICG) is an FDA-approved medical diagnostic agent that is widely used as a near-infrared (NIR) fluorescent imaging molecular probe. However, ICG tends to aggregate to form dimers or H-aggregates in water and lacks physical and optical stability, which greatly decreases its absorbance and fluorescence intensity in various applications. Additionally, ICG has no tissue- or tumor-targeting properties, and its structure is not easy to modify, which has further limited its application in cancer diagnosis. In this study, we addressed these challenges by developing a supramolecular colloidal carrier system that targets tumor cells. To this end, we synthesized a water-soluble ß-cyclodextrin (ß-CD) polymer conjugated with folate (FA), denoted PCD-FA, which is capable of forming inclusion complexes with ICG in water through host-guest interactions between the ß-CD moieties and ICG molecules. The inclusion complexes formed by PCD-FA and ICG, called ICG@PCD-FA, dispersed stably in solution as colloidal nanoparticles, greatly improving the physical and optical properties of ICG by preventing ICG dimer formation, where ICG appeared as monomers and even J-aggregates. This resulted in stronger and more stable absorption at a longer wavelength of 900 nm, which may allow for deeper tissue penetration and imaging with reduced interference from biological tissues' autofluorescence. Moreover, ICG@PCD-FA showed a targeting effect on folate receptor-positive (FR+) tumor cells, which specifically highlighted FR+ cells via NIR endoscopic imaging. Notably, ICG@PCD-FA further improved permeation and accumulation in FR+ 3D tumor spheroids. Therefore, this ICG@PCD-FA supramolecular colloidal system may have a great potential for use in tumor NIR imaging and diagnostic applications.


Asunto(s)
Coloides , Ácido Fólico , Verde de Indocianina , Esferoides Celulares , beta-Ciclodextrinas , Verde de Indocianina/química , beta-Ciclodextrinas/química , Ácido Fólico/química , Humanos , Coloides/química , Imagen Óptica , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Tamaño de la Partícula , Células Tumorales Cultivadas , Polímeros/química , Nanopartículas/química
9.
Int J Biol Macromol ; 266(Pt 2): 130619, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38460629

RESUMEN

Lignin, a natural polyphenol polymer, is a biocompatible, cost-effective and accessible material. To fully utilize the benefits of lignin, it is crucial to transform its complex macromolecules into nanoscale particles in a single solvent. In this research, an assembly-mediated internal cross-linking method in single solvent was proposed to manufacture cross-linked lignin colloidal particles with nanoscale particle size controlled to be around 50 nm. Then, cross-linked lignin composite particles with a unique "patchy" structure for dental cleansing were obtained by rapidly grafting the cross-linked lignin colloidal particles onto the surface of silica microspheres through the bridging effect of silane coupling agent. The resulting composite particles have rivets with adjustable hardness, significantly lower than traditional abrasives like silica in both hardness and modulus. Through the group cleansing behavior of soft interlocking, a breakthrough has been achieved in the high solid content agglomeration friction mode of traditional abrasives, which effectively reduces tooth wear and exhibits an excellent plaque removal effect.


Asunto(s)
Lignina , Lignina/química , Tamaño de la Partícula , Dióxido de Silicio/química , Reactivos de Enlaces Cruzados/química , Dureza , Microesferas , Humanos , Coloides/química , Nanopartículas/química
10.
Proc Natl Acad Sci U S A ; 121(5): e2305770121, 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38227645

RESUMEN

Acylated peptides composed of glucagon-like peptide-1 receptor agonists modified with a fatty acid side chain are an important class of therapeutics for type 2 diabetes and obesity but are susceptible to an unusual physical instability in the presence of hydrophobic surfaces, i.e., spontaneous emulsification, also known as ouzo formation in practice. In this work, light scattering, small-angle X-ray scattering, and circular dichroism measurements are used to characterize the physical properties of the semaglutide colloidal phase, including size distribution, shape, secondary structure, internal structure, and internal composition, as a function of solution physico-chemical conditions. The existence and size of the colloids formed are successfully predicted by a classical Rayleigh model, which identifies the parameters controlling their size and formation. Colloid formation is found to be catalyzed by hydrophobic surfaces, and formation rates are modeled as an autocatalytic reaction, enabling the formation of a master curve for various surfaces that elucidates the mechanism. Surfaces differ due to differences in surface wettability, which can be correlated with Hansen solubility parameters. This work provides insights into this unusual colloidal phenomenon and guides the peptide synthesis process and drug product formulation in the pharmaceutical industry.


Asunto(s)
Diabetes Mellitus Tipo 2 , Humanos , Péptidos Similares al Glucagón , Humectabilidad , Péptidos , Coloides/química , Receptor del Péptido 1 Similar al Glucagón/agonistas , Hipoglucemiantes
11.
J Oleo Sci ; 72(9): 819-829, 2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37574284

RESUMEN

Oleofoams have garnered significant attention in many personal care applications because of their favorable physicochemical properties, including texture and detergency. To explore the potential use of mixtures of high-melting-point fat crystals (tribehenoyl-glycerol [BBB]) and edible oils as low-cost and stable aeration systems, we created oleofoams composed of olive oil and BBB. By whipping the BBB/olive oil oleogels after rapid cooling and subsequent heating, we successfully prepared oleofoams without emulsifier additives. Mixtures of the BBB/olive oil formed oleofoams at BBB concentrations of 4.0-20.0 wt.%. The resultant oleofoams maintained their overrun rates and did not coalesce, even with additional whipping after the overrun rate was maximized. More closely packed bubbles, concentrated bubble size distributions, and stronger interfacial elasticity were attributed to the increasing BBB concentrations, and the thermal results revealed that further heating was required to damage the foam structure. The characteristics of these new oleofoams are closely related to their BBB concentrations, and the observed effects are attributed to the network structure of the thickened crystal layer and enhanced gelling in the oil phase.


Asunto(s)
Glicerol , Coloides/química , Glicerol/química , Aceite de Oliva/química , Reología
12.
Sci Total Environ ; 890: 164419, 2023 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-37236457

RESUMEN

Accurate data of cadmium (Cd) and uranium (U) leaching are needed in the context of identifying their mass balances in agricultural soils. There is some controversy related to sampling methods and the contribution of colloid facilitated transport. Here, leaching was measured in undisturbed unsaturated soils and the impact of colloids was measured with due attention to solution sampling protocols. Soils were sampled in an arable, pH neutral silty loam soil. The columns (n = 8) were irrigated and PTFE suction plates (1 µm pores) at the bottom ensured unsaturated flow. New here is that both percolates and associated suction plates were collected, the elements in the plates were recovered with acid digestion and used as a lower estimate of colloidal forms. The fraction of elements collected in the plates were 33 % (Cd) and 80 % (U) of the total mobility (=percolates + plates), illustrating colloidal transport. Composition of pore water extracted by soil centrifugation varied largely between initial and final samples and showed that colloids increased as a result of reduced solution calcium after leaching two pore volumes with low calcium water. Flow Field-Flow Fractionation (FIFFF) of the pore water and percolates revealed co-elution of U with colloidal organic matter, oxyhydroxides and clay, illustrating colloidal transport of U by these vectors. Colloidal transport of Cd was less pronounced and was dominated by organic matter. Soil extracts with 0.01 M CaCl2 have lower colloid concentration and consequently underestimate mobile U. In contrast, Cd concentrations in 0.01 M CaCl2 extracts exceed that of percolates due to chloride complexation and higher calcium, mobilizing Cd. Soil leaching experiments better indicate potential leaching losses than a single pore water composition because the former yields the time integrated data. Suction plates and/or bottom filters need to be analysed in leaching studies to account for metal transport by colloids.


Asunto(s)
Contaminantes del Suelo , Uranio , Cadmio/análisis , Suelo/química , Uranio/análisis , Calcio/análisis , Cloruro de Calcio , Contaminantes del Suelo/análisis , Agua/análisis , Coloides/química
13.
Colloids Surf B Biointerfaces ; 224: 113198, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36773411

RESUMEN

Colloidal stabilization of magnetic nanoparticles is one of the most important steps in the preparation of magnetic nanoparticles for potential biomedical applications. A special kind of magnetic nanoparticle are barium hexaferrite nanoplatelets (BSHF NPLs) with a hexagonal shape and a permanent magnetic moment. One strategy for the stabilization of BHF in aqueous media is to use coatings. In our research, we used an eco-friendly tannic acid, as a coating on BSHF NPLs. As-prepared BSHF NPLs coated with tannic acid were examined with transmission electron microscopy, infrared and UV-Vis spectroscopy, electro-kinetic measurements, and their room-temperature magnetic properties were measured. Stable colloids were tested in two biological complex media and antimicrobial properties of the material were examined. To enhance the antimicrobial properties of our material, we used tannic acid as a platform for the in-situ production of silver on BSHF NPLs. New hybrid material with silver also possesses magnetic properties and excellent antimicrobial activity against Escherichia coli and Staphylococcus aureus.


Asunto(s)
Antiinfecciosos , Nanopartículas del Metal , Antibacterianos/farmacología , Antibacterianos/química , Polifenoles , Plata/química , Antiinfecciosos/farmacología , Taninos/farmacología , Coloides/química , Fenómenos Magnéticos , Nanopartículas del Metal/química
14.
J Colloid Interface Sci ; 629(Pt A): 173-181, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36081202

RESUMEN

HYPOTHESIS: Colloids with rough topography demonstrate more complex interactions and tremendous potential in industrial applications. However, relevant studies suffer from a range of challenges, including cumbersome synthesis, complex characterization, and very limited functionalities. A comprehensive study of rough nanoparticles can not only broaden our understanding of rough colloids, but also help to avoid some of their detrimental impacts in real life (e.g., clogging and pumping failures in slurry processing). EXPERIMENTS: A facile route to precisely control the surface roughness of silica nanoparticles and a highly efficient method to characterize the surface roughness were developed respectively. The fabricated particles can be applied for the immobilization of metal nanostructures; their cytotoxic effects and the capability to be used as a drug-delivery vehicle were also evaluated. FINDINGS: Modifying the addition time of precursors (i.e., TEOS and MPTMS) can precisely control the surface roughness of silica nanoparticles. The developed characterization method based on TEM observations allows statistical analyses on a large number of particles, and therefore features very reasonable accuracy. These rough particles behave like microporous materials, where the loading strategy is closely related to their surface roughness. Medium rough particles are promising carriers of metal nanostructures, while the roughest ones are excellent candidate for doxorubicin delivery to cancer cells.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Dióxido de Silicio/química , Nanopartículas/química , Doxorrubicina/farmacología , Coloides/química , Sistemas de Liberación de Medicamentos
15.
Sci Rep ; 12(1): 17116, 2022 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-36224240

RESUMEN

The valorization of new polymer sources from underutilized plants as structuring, encapsulating, and texturizing agents for food and nutraceutical applications is gaining attention. This provides an opportunity where inexpensive plant-sourced biopolymers can play an impactful role, on both ecological and economic aspects performing equivalently effectual yet cost-effective substitutes to synthetic polymers. With this aim, we explored the use of mucilage from Althea rosea and reveal its physicochemical, in vitro antidiabetic and antihypertensive activity. Besides, structural, micrometric, crystallization, and anti-microbial properties was also seen. We determined the probable structure of the extracted mucilage by FTIR which confirmed the residues of saccharides as galactose and uronic acid with α and ß configurations. It consists of 78.26% carbohydrates, 3.51% ashes, and 3.72% proteins. Here, we show that the mucilage offered protection to DNA against the oxidative damage caused by (-OH) radicals and the morphology of the mucilage particles displayed a fibrillary material settled in a net-like, tangled structure. Our results demonstrate that the reconstituted mucilage powder exhibited good water holding capacity (2.89 g water/g mucilage), solubility (27.33%), and oil holding capacity (1.79 g oil/g mucilage). Moreover, high emulsifying property (95.83%) and foaming capacity (17.04%) was noted. Our results indicate that A.rosea mucilage can potentially serve as economical and eco-friendly hydrocolloid substitute for the food and nutraceutical industry owing to its functional, hypo-lipidemic, anti-hyperglycemic, antioxidant, and anti-bacterial properties.


Asunto(s)
Mucílago de Planta , Antihipertensivos/farmacología , Antioxidantes/farmacología , Coloides/química , Galactosa , Hipoglucemiantes/farmacología , Mucílago de Planta/química , Polisacáridos/química , Polisacáridos/farmacología , Polvos , Ácidos Urónicos , Agua/química
16.
Environ Pollut ; 315: 120315, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36216178

RESUMEN

Steroid estrogens (SEs) as typical endocrine disrupting compounds (EDCs) are widely detected in terrestrial environment, whilst the transport of SEs in groundwater remains unwell understood. Specifically, the effects of ubiquitous natural colloids on the SEs transport are unclear in subsurface environment, especially in aquifer systems. Here, the influence of inorganic colloids (i.e. silica and illite) and organic colloids, i.e. Humic acid (HA), on the transport of estrone (E1) and estradiol (E2) in saturated porous media was studied utilizing laboratory scale column experiments. Characterization on the colloids and porous aquifer material was conducted to provide a basis for interpretation of the experimental findings. Results showed that the transport of SEs was clearly affected by the natural colloids migrating through the saturated porous media. About 38.5% of E1 and 24.6% of E2 were retained in the column when colloids were absent in the system. When transporting with silica colloids, illite colloids, and HA colloids, the transport of E1 was enhanced by 15.64%, 11.17% and 25.60%, respectively; whilst the transport of E2 was improved by 19.56%, 23.06% and 36.40%, respectively. The SEs transport enhancement by colloids depended upon not only the mobility of the colloids but also their geochemical characteristics. The organic colloids showed 1.5-2.5 times greater ability on promoting the transport of SEs than the inorganic ones tested in this study. The proposed mechanisms of nature colloids facilitated transport of SEs including competing for adsorption sites on the sand surfaces by the colloids resulting mobilization of adsorbed SEs from solid matrix, and transport of colloids as carriers for SEs.


Asunto(s)
Coloides , Sustancias Húmicas , Porosidad , Coloides/química , Adsorción , Sustancias Húmicas/análisis , Dióxido de Silicio , Estrógenos
17.
Adv Colloid Interface Sci ; 309: 102774, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36152373

RESUMEN

A comprehensive understanding of interfacial behavior in water/oil/surfactant systems is critical to evaluating the performance of emulsions in various industries, specifically in the oil and gas industry. To gain fundamental knowledge regarding this interfacial behavior, atomistic methods, e.g., molecular dynamics (MD) simulation, can be employed; however, MD simulation cannot handle phenomena that require more than a million atoms. The coarse-grained mesoscale methods were introduced to resolve this issue. One of the most effective mesoscale coarse-grained approaches for simulating colloidal systems is dissipative particle dynamics (DPD), which bridges the gap between macroscopic time and length scales and molecular-scale simulation. This work reviews the fundamentals of DPD simulation and its progress on colloids and interface systems, especially surfactant/water/oil mixtures. The effects of temperature, salt content, a water/oil ratio, a shear rate, and a type of surfactant on the interfacial behavior in water/oil/surfactant systems using DPD simulation are evaluated. In addition, the obtained results are also investigated through the lens of the chemistry of surfactants and emulsions. The outcome of this comprehensive review demonstrates the importance of DPD simulation in various processes with a focus on the colloidal and interfacial behavior of surfactants at water-oil interfaces.


Asunto(s)
Surfactantes Pulmonares , Tensoactivos , Tensoactivos/química , Agua/química , Coloides/química , Simulación de Dinámica Molecular , Emulsiones
18.
Carbohydr Polym ; 287: 119331, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35422278

RESUMEN

Due to the rapid reaction kinetics, the morphology of chitosan/tripolyphosphate nanoparticles was difficult to control. We mixed chitosan and tripolyphosphate through a multi-inlet vortex mixer at different mixing efficiency and characteristic mixing time (τmix). Below a critical τmix, the aggregation of primary chitosan/TPP particles can be ceased. The corresponding aggregation time of primary particles (τagg) was dependent on the ionic strength, the degree of deacetylation and molecular weight of chitosan. Moreover, the particle compactness was estimated from the hydrodynamic diameter and the turbidity using a model based on the Mie theory. Slow and nonhomogeneous mixing led to more compact nanoparticles, while rapid and homogeneous mixing produced nanoparticles with a higher swelling ratio. Besides, the ionic strength and polymer concentration could affect the internal structure of nanoparticles. This study revealed the significance of mixing on the internal structure of chitosan/TPP nanoparticles, which could guide the preparation of other ionically-crosslinked polysaccharide colloids.


Asunto(s)
Quitosano , Nanopartículas , Quitosano/química , Coloides/química , Nanopartículas/química , Tamaño de la Partícula , Polifosfatos/química
19.
Nat Mater ; 21(5): 540-546, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35332292

RESUMEN

Precise and selective manipulation of colloids and biological cells has long been motivated by applications in materials science, physics and the life sciences. Here we introduce our harmonic acoustics for a non-contact, dynamic, selective (HANDS) particle manipulation platform, which enables the reversible assembly of colloidal crystals or cells via the modulation of acoustic trapping positions with subwavelength resolution. We compose Fourier-synthesized harmonic waves to create soft acoustic lattices and colloidal crystals without using surface treatment or modifying their material properties. We have achieved active control of the lattice constant to dynamically modulate the interparticle distance in a high-throughput (>100 pairs), precise, selective and reversible manner. Furthermore, we apply this HANDS platform to quantify the intercellular adhesion forces among various cancer cell lines. Our biocompatible HANDS platform provides a highly versatile particle manipulation method that can handle soft matter and measure the interaction forces between living cells with high sensitivity.


Asunto(s)
Acústica , Coloides , Coloides/química , Ciencia de los Materiales
20.
Biomed Res Int ; 2022: 9863616, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35299896

RESUMEN

Copper oxide (CuO) nanoparticle- (NP-) decorated carbon NPs (CNPs) were produced as colloidal suspension through pulsed laser ablation technique in liquid (PLAL) medium. The antimicrobial activity of the produced NPs was tested against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), and anticancer activity was tested against breast cancer cell line, MCF-7, together with the biocompatibility assessment of these NPs. The X-ray diffraction (XRD) patterns of the obtained CNPs showed peaks at 26.58° and 43.78° (2θ) identical to (002) and (111) planes, respectively, of the carbon phases. It also displayed new peaks at 38.5° and 48.64° (2θ) after doping with CuO NPs. Transmission electron microscope (TEM) images revealed the crystalline nature with the spherical shape of the prepared CNPs with 5-40 nm diameter ranges. In addition, the NP effects on the bacterial cell walls and nucleic acid were confirmed using a scanning electron microscope (SEM) and microscopic fluorescence analysis. The NPs showed antibacterial activity through SEM examinations against the pathogenic microbial species, S. aureus and E. coli. In the cellular material release assay, the optical density of the bacterial cells, treated with NPs, displayed a significant increase with the time of exposure to NPs, and the cytotoxicity reached more than 80% of the level for the CNPs decorated with CuO NPs. The morphology of the MCF-7 cells treated with NPs decreased numbers, and the loss of contact with the surrounding cells was observed. These results confirmed that the CNPs decorated with CuO NPs have no observable side effects and can be safely used for therapeutic applications. It is also noteworthy that it is the first report of preparation of CuO NPs decorated with CNPs (CuO NPs-CNPs) by PLAL, and the produced NPs showed antimicrobial antiproliferative activities against breast cancer cell lines, MCF-7. The main advantage of the PLAL technique of synthesizing CuO NPs-CNPs provided a two-step, cost-effective, and eco-friendly method.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Carbono/química , Carbono/farmacología , Cobre/química , Cobre/farmacología , Nanopartículas del Metal/química , Coloides/química , Coloides/farmacología , Escherichia coli/efectos de los fármacos , Femenino , Humanos , Terapia por Láser , Células MCF-7 , Staphylococcus aureus/efectos de los fármacos
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