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1.
J Chromatogr A ; 1645: 462067, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-33853009

RESUMEN

Through theoretical computation, it was demonstrated that perfluorobenzene can form π-hole⋅⋅⋅π bonds with polycyclic aromatic hydrocarbons (PAHs). Then, the π-hole bond was firstly introduced in solid phase extraction in which perfluorobenzene-bonded silica sorbent was synthesized and used for the solid phase extraction of sixteen PAHs in water. Compared with the traditional octadecyl silica sorbent, the perfluorobenzene-bonded silica sorbent showed higher adsorbabilities for the PAHs with 4-6 benzene rings, for which the recoveries increased by approximately 20%. Under the optimized conditions, the proposed SPE-HPLC-FLD/UV method was successfully applied for the analysis of 16 PAHs in river water and waste water samples with the limits of detection ranged from 0.002 to 0.08 µg⋅L-1. In addition, when the perfluorobenzene-bonded silica sorbent compared with the phenyl-bonded silica sorbent, the results indicated that π-hole⋅⋅⋅π bonds between perfluorobenzene and PAHs were stronger than the π-π interactions between the PAHs and benzene in hexane solution, which highlights the remarkable potential for the application of the π-hole bond in the SPE field.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Extracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Cromatografía Líquida de Alta Presión , Límite de Detección , Hidrocarburos Policíclicos Aromáticos/química , Dióxido de Silicio/química , Contaminantes Químicos del Agua/química
2.
J Chromatogr A ; 1645: 462107, 2021 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-33857677

RESUMEN

In the analysis of contaminants in food products, sample preparation is performed by proper adsorbents, whose choice is crucial to eliminate matrix interference. In this work we modified SBA-15 adsorbents by functionalization with (3-aminopropyl)-triethoxysilane (SBA-15-APTES) and N-[3-(trimethoxysilyl)propyl]aniline (SBA-15-AN) aiming to use them for the first time in the clean-up step of a QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction of micropollutants from strawberry, a sugar rich fruit. After physico-chemical characterization by nitrogen adsorption, infrared spectroscopy and thermogravimetric analysis, the adsorption capabilities of SBA-15 sorbents and possible interaction mechanisms were studied at different pH (2.1-8.5) for glucose, sucrose and fructose at concentrations characteristic of those found in strawberries. The performance of the two SBA-15 sorbents was compared with that of commercial PSA (primary secondary amine), usually proposed in QuEChERS protocols. Both SBA-15 materials exhibit up to 30% higher adsorption than PSA, suggesting their possible QuEChERS application. Synthesized SBA-15 adsorbents were hence used as innovative dispersive sorbents in the QuEChERS extractions of 13 PAHs and 14 PCBs from strawberry. For PCBs, SBA-15-AN provides better matrix removal than PSA and comparable extraction recoveries around 90%. For PAHs, the use of SBA-15-AN has the advantage of lower relative standard deviation (7%) than PSA (19%).


Asunto(s)
Contaminantes Ambientales/análisis , Dióxido de Silicio/química , Extracción en Fase Sólida/métodos , Adsorción , Fragaria/química , Frutas/química , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis
3.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802614

RESUMEN

In this study, dense gold-assembled SiO2 nanostructure (SiO2@Au) was successfully developed using the Au seed-mediated growth. First, SiO2 (150 nm) was prepared, modified by amino groups, and incubated by gold nanoparticles (ca. 3 nm Au metal nanoparticles (NPs)) to immobilize Au NPs to SiO2 surface. Then, Au NPs were grown on the prepared SiO2@Au seed by reducing chloroauric acid (HAuCl4) by ascorbic acid (AA) in the presence of polyvinylpyrrolidone (PVP). The presence of bigger (ca. 20 nm) Au NPs on the SiO2 surface was confirmed by transmittance electronic microscopy (TEM) images, color changes to dark blue, and UV-vis spectra broadening in the range of 450 to 750 nm. The SiO2@Au nanostructure showed several advantages compared to the hydrofluoric acid (HF)-treated SiO2@Au, such as easy separation, surface modification stability by 11-mercaptopundecanoic acid (R-COOH), 11-mercapto-1-undecanol (R-OH), and 1-undecanethiol (R-CH3), and a better peroxidase-like catalysis activity for 5,5'-Tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) reaction. The catalytic activity of SiO2@Au was two times better than that of HF-treated SiO2@Au. When SiO2@Au nanostructure was used as a surface enhanced Raman scattering (SERS) substrate, the signal of 4-aminophenol (4-ATP) on the surface of SiO2@Au was also stronger than that of HF-treated SiO2@Au. This study provides a potential method for nanoparticle preparation which can be replaced for Au NPs in further research and development.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Nanoestructuras/química , Dióxido de Silicio/química , Aminofenoles/química , Bencidinas/química , Técnicas Biosensibles/métodos , Catálisis , Ácido Fluorhídrico/química , Peróxido de Hidrógeno/química , Límite de Detección , Povidona/química , Plata/química , Compuestos de Sulfhidrilo/química
4.
Int J Mol Sci ; 22(4)2021 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-33672949

RESUMEN

Two different types of ordered mesoporous nanoparticles, namely MCM-41 and MCM-48, with similar pore sizes but different pore connectivity, were loaded with aprepitant via a passive diffusion method. The percentage of the loaded active agent, along with the encapsulation efficiency, was evaluated using High-performance Liquid Chromatography (HPLC) analysis complemented by Thermogravimetric Analysis (TGA). The determination of the pore properties of the mesoporous particles before and after the drug loading revealed the presence of confined aprepitant in the pore structure of the particles, while Powder X-ray Diffractometry(pXRD), Differential Scanning Calorimetry (DSC), and FTIR experiments indicated that the drug is in an amorphous state. The release profiles of the drug from the two different mesoporous materials were studied in various release media and revealed an aprepitant release up to 45% when sink conditions are applied. The cytocompatibility of the silica nanoparticles was assessed in Caco-2 cell monolayers, in the presence and absence of the active agent, suggesting that they can be used as carriers of aprepitant without presenting any toxicity in vitro.


Asunto(s)
Aprepitant/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas/química , Dióxido de Silicio/química , Administración Oral , Antieméticos/administración & dosificación , Antieméticos/farmacocinética , Aprepitant/farmacocinética , Células CACO-2 , Rastreo Diferencial de Calorimetría , Cromatografía Líquida de Alta Presión , Difusión , Liberación de Fármacos , Humanos , Microscopía Electrónica de Rastreo , Nanopartículas/ultraestructura , Tamaño de la Partícula , Porosidad , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier
5.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670482

RESUMEN

In this paper, the structural and optical properties of ZnO-SiO2-based ceramics fabricated from oil palm empty fruit bunch (OPEFB) were investigated. The OPEFB waste was burned at 600, 700 and 800 °C to form palm ash and was then treated with sulfuric acid to extract silica from the ash. X-ray fluorescence (XRF) and X-ray diffraction (XRD) analyses confirmed the existence of SiO2 in the sample. Field emission scanning electron microscopy (FESEM) showed that the particles displayed an irregular shape and became finer after leaching. Then, the solid-state method was used to produce the ZnO-SiO2 composite and the samples were sintered at 600, 800, 1000, 1200 and 1400 °C. The XRD peaks of the Zn2SiO4 showed high intensity, which indicated high crystallinity of the composite. FESEM images proved that the grain boundaries were larger as the temperature increased. Upon obtaining the absorbance spectrum from ultraviolet-visible (UV-Vis) spectroscopy, the energy band gaps obtained were 3.192, 3.202 and 3.214 eV at room temperature, 600 and 800 °C, respectively, and decreased to 3.127, 2.854 and 2.609 eV at 1000, 1200 and 1400 °C, respectively. OPEFB shows high potential as a silica source in producing promising optical materials.


Asunto(s)
Frutas/química , Aceite de Palma/química , Dióxido de Silicio/síntesis química , Óxido de Zinc/síntesis química , Dióxido de Silicio/química , Análisis Espectral , Temperatura , Residuos , Difracción de Rayos X , Óxido de Zinc/química
6.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670610

RESUMEN

This paper presents a facile and low-cost strategy for fabrication lysozyme-loaded mesoporous silica nanotubes (MSNTs) by using silk fibroin (SF) nanofiber templates. The "top-down method" was adopted to dissolve degummed silk in CaCl2/ formic acid (FA) solvent, and the solution containing SF nanofibrils was used for electrospinning to prepare SF nanofiber templates. As SF contains a large number of -OH, -NH2 and -COOH groups, the silica layer could be easily formed on its surface by the Söber sol-gel method without adding any surfactant or coupling agent. After calcination, the MSNTs were obtained with inner diameters about 200 nm, the wall thickness ranges from 37 ± 2 nm to 66 ± 3 nm and the Brunauer-Emmett-Teller (BET) specific surface area was up to 200.48 m2/g, the pore volume was 1.109 cm3/g. By loading lysozyme, the MSNTs exhibited relatively high drug encapsulation efficiency up to 31.82% and an excellent long-term sustained release in 360 h (15 days). These results suggest that the MSNTs with the hierarchical structure of mesoporous and macroporous will be a promising carrier for applications in biomacromolecular drug delivery systems.


Asunto(s)
Fibroínas/química , Muramidasa/metabolismo , Nanofibras/química , Nanotubos/química , Dióxido de Silicio/química , Cloruro de Calcio/química , Liberación de Fármacos , Formiatos/química , Nanofibras/ultraestructura , Nanotubos/ultraestructura , Porosidad , Silanos/química , Soluciones , Espectrometría por Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Termogravimetría , Viscosidad
7.
Molecules ; 26(4)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671351

RESUMEN

The strong demand for rare-earth elements (REEs) is driven by their wide use in high-tech devices. New processes have to be developed for valorizing low-grade ores or alternative metal sources (such as wastes and spent materials). The present work contributed to the development of new sorbents for the recovery of rare earth ions from aqueous solutions. Functionalized mesoporous silica composite was synthesized by grafting diethylenetriamine onto composite support. The physical and chemical properties of the new sorbent are characterized using BET, TGA, elemental analysis, titration, FTIR, and XPS spectroscopies to identify the reactive groups (amine groups: 3.25 mmol N g-1 and 3.41 by EA and titration, respectively) and their mode of interaction with Nd(III) and Gd(III). The sorption capacity at the optimum pH (i.e., 4) reaches 0.9 mmol Nd g-1 and 1 mmol Gd g-1. Uptake kinetics are modeled by the pseudo-first-order rate equation (equilibrium time: 30-40 min). At pH close to 4-5, the sorbent shows high selectivity for rare-earth elements against alkali-earth elements. This selectivity is confirmed by the efficient recovery of REEs from acidic leachates of gibbsite ore. After elution (using 0.5 M HCl solutions), selective precipitation (using oxalate solutions), and calcination, pure rare earth oxides were obtained. The sorbent shows promising perspective due to its high and fast sorption properties for REEs, good recycling, and high selectivity.


Asunto(s)
Aminas/química , Gadolinio/química , Neodimio/química , Polímeros/química , Dióxido de Silicio/química , Adsorción , Concentración de Iones de Hidrógeno , Residuos Industriales/análisis , Cinética , Espectroscopía de Fotoelectrones , Porosidad , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier
8.
Molecules ; 26(4)2021 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-33673084

RESUMEN

The controlled design of robust, well reproducible, and functional nanomaterials made according to simple processes is of key importance to envision future applications. In the field of porous materials, tuning nanoparticle features such as specific area, pore size and morphology by adjusting simple parameters such as pH, temperature or solvent is highly needed. In this work, we address the tunable control of the pore morphology of mesoporous silica (MS) nanoparticles (NPs) with the sol-gel reaction temperature (Tsg). We show that the pore morphology of MS NPs alone or of MS shell covering iron oxide nanoparticles (IO NPs) can be easily tailored with Tsg orienting either towards stellar (ST) morphology (large radial pore of around 10 nm) below 80 °C or towards a worm-like (WL) morphology (small randomly oriented pores channel network, of 3-4 nm pore size) above 80 °C. The relaxometric and magnetothermal features of IO@STMS or IO@WLMS core shell NPs having respectively stellar or worm-like morphologies are compared and discussed to understand the role of the pore structure for MRI and magnetic hyperthermia applications.


Asunto(s)
Portadores de Fármacos/química , Nanopartículas/química , Dióxido de Silicio/química , Concentración de Iones de Hidrógeno , Imagen por Resonancia Magnética , Nanopartículas/ultraestructura , Tamaño de la Partícula , Porosidad , Temperatura
9.
Int J Nanomedicine ; 16: 1929-1942, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727807

RESUMEN

Background: Staphylococcus aureus biofilms pose a unique challenge in healthcare due to their tolerance to a wide range of antimicrobial agents. The high cost and lengthy timeline to develop novel therapeutic agents have pushed researchers to investigate the use of nanomaterials to deliver antibiofilm agents and target biofilm infections more efficiently. Previous studies have concentrated on improving the efficacy of antibiotics by deploying nanoparticles as nanocarriers. However, the dispersal of the extracellular polymeric substance (EPS) matrix in biofilm-associated infections is also critical to the development of novel nanoparticle-based therapies. Methods: This study evaluated the efficacy of enzyme-functionalized mesoporous silica nanoparticles (MSNs) against methicillin-resistant S. aureus (MRSA) and methicillin-sensitive S. aureus (MSSA) biofilms. MSNs were functionalized with the enzyme lysostaphin, which causes cell lysis of S. aureus bacteria. This was combined with two other enzyme functionalized MSNs, serrapeptase and DNase I which will degrade protein and eDNA in the EPS matrix, to enhance eradication of the biofilm. Cell viability after treatment with enzyme-functionalized MSNs was assessed using a MTT assay and CLSM, while crystal violet staining was used to assess EPS removal. Results: The efficacy of all three enzymes against S. aureus cells and biofilms was significantly improved when they were immobilized onto MSNs. Treatment efficacy was further enhanced when the three enzymes were used in combination against both MRSA and MSSA. Regardless of biofilm maturity (24 or 48 h), near-complete dispersal and killing of MRSA biofilms were observed after treatment with the enzyme-functionalized MSNs. Disruption of mature MSSA biofilms with a polysaccharide EPS was less efficient, but cell viability was significantly reduced. Conclusion: The combination of these three enzymes and their functionalization onto nanoparticles might extend the therapeutic options for the treatment of S. aureus infections, particularly those with a biofilm component.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Enzimas/metabolismo , Nanopartículas/química , Dióxido de Silicio/química , Staphylococcus aureus/fisiología , Biomasa , Supervivencia Celular , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Humanos , Staphylococcus aureus Resistente a Meticilina/fisiología , Pruebas de Sensibilidad Microbiana , Nanopartículas/ultraestructura , Porosidad
10.
Int J Nanomedicine ; 16: 1943-1960, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727808

RESUMEN

Introduction: The overexpression of Human Epidermal Growth Factor Receptor 2 (HER2) is usually associated with aggressive and infiltrating breast cancer (BC) phenotype, and metastases. Functionalized silica-based nanocarriers (SiNPs) can be labeled for in vivo imaging applications and loaded with chemotherapy drugs, making possible the simultaneous noninvasive diagnosis and treatment (theranostic) for HER2-positive BC. Methods: Firstly, FITC-filled SiNPs, were engineered with two different amounts of Hc-TZ (trastuzumab half-chain) per single nanoparticle (1:2 and 1:8, SiNPs to Hc-TZ ratio), which was 99mTc-radiolabeled at histidine residues for ex vivo and in vivo biodistribution evaluations. Secondly, nanoparticles were loaded with DOX and their in vitro and ex vivo/in vivo delivery was assessed, in comparison with liposomal Doxorubicin (Caelyx). Finally, the treatment efficacy of DOX-SiNPs-TZ (1:8 Hc-TZ) was evaluated in vivo by PET and supported by MS-based proteomics profiling of tumors. Results: SiNPs-TZ (1:8 Hc-TZ) tumor uptake was significantly greater than that of SiNPs-TZ (1:2 Hc-TZ) at 6 hours post-injection (p.i.) in ex vivo biodistribution experiment. At 24 h p.i., radioactivity values remained steady. Fluorescence microscopy, confirmed the presence of radiolabeled SiNPs-TZ (1:8 Hc-TZ) within tumor even at later times. SiNPs-TZ (1:8 Hc-TZ) nanoparticles loaded with Doxorubicin (DOX-SiNPs-TZ) showed a similar DOX delivery capability than Caelyx (at 6 h p.i.), in in vitro and ex vivo assays. Nevertheless, at the end of treatment, tumor volume was significantly reduced by DOX-SiNPs-TZ (1:8 Hc-TZ), compared to Caelyx and DOX-SiNPs treatment. Proteomics study identified 88 high stringent differentially expressed proteins comparing the three treatment groups with controls. Conclusion: These findings demonstrated a promising detection specificity and treatment efficacy for our system (SiNPs-TZ, 1:8 Hc-TZ), encouraging its potential use as a new theranostic agent for HER2-positive BC lesions. In addition, proteomic profile confirmed that a set of proteins, related to tumor aggressiveness, were positively affected by targeted nanoparticles.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Portadores de Fármacos/química , Nanopartículas/química , Radiofármacos/química , Receptor ErbB-2/metabolismo , Dióxido de Silicio/química , Tecnecio/química , Animales , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Modelos Animales de Enfermedad , Doxorrubicina/análogos & derivados , Doxorrubicina/química , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Endocitosis , Femenino , Fluoresceína-5-Isotiocianato/química , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Polietilenglicoles/química , Polietilenglicoles/farmacología , Polietilenglicoles/uso terapéutico , Proteoma/metabolismo , Proteómica , Radiofármacos/farmacocinética , Tecnecio/farmacocinética , Distribución Tisular/efectos de los fármacos , Tomografía Computarizada de Emisión de Fotón Único , Resultado del Tratamiento
11.
Int J Nanomedicine ; 16: 1961-1976, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33727809

RESUMEN

Introduction: Metastatic breast cancer seriously harms women's health and is currently the tumour type with the highest mortality rate in women. Recently, the combinatorial therapeutic approaches that integrate anti-cancer drugs and genetic agents is an attractive and promising strategy for the treatment of metastatic breast cancer. Moreover, such a combination strategy requires better drug carriers that can effectively deliver the cargo to the breast cancer cells and achieve controlled release in the cells to achieve better therapeutic effects. Methods: The tumour-targeted and redox-responsive mesoporous silica nanoparticles (MSNs) functionalised with DNA aptamers (AS1411) as a co-delivery system was developed and investigated for the potential against metastatic breast cancer. Doxorubicin (Dox) was loaded onto the MSNs, while AS1411 and a small interfering RNA (siTIE2) were employed as gatekeepers via attachment to the MSNs with redox-sensitive disulfide bonds. Results: The controlled release of Dox and siTIE2 was associated with intracellular glutathione. AS1411 mediated the targeted delivery of Dox by increasing its cellular uptake in metastatic breast cancer, ultimately resulting in a lower IC50 in MDA-MB-231 cells (human breast cancer cell line with high metastatic potency), improved biodistribution in tumour-bearing mice, and enhanced in vivo anti-tumour effects. The in vitro cell migration/invasion assay and in vivo anti-metastatic study revealed synergism in the co-delivery system that suppresses cancer cell metastasis. Conclusion: The tumour-targeted and redox-responsive MSN prepared in this study are promising for the effective delivery and controlled release of Dox and siTIE2 for improved treatment of metastatic breast cancer.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Doxorrubicina/uso terapéutico , Nanopartículas/química , ARN Interferente Pequeño/administración & dosificación , Dióxido de Silicio/química , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias de la Mama/patología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada/farmacología , Preparaciones de Acción Retardada/uso terapéutico , Doxorrubicina/farmacología , Portadores de Fármacos/química , Endocitosis/efectos de los fármacos , Femenino , Células HEK293 , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Nanopartículas/ultraestructura , Invasividad Neoplásica , Metástasis de la Neoplasia , Oxidación-Reducción , Porosidad , ARN Interferente Pequeño/farmacología , Distribución Tisular/efectos de los fármacos
12.
J Chromatogr A ; 1642: 462030, 2021 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-33721812

RESUMEN

The total solute retention by a chemically modified stationary phase (CMSP) has been shown several times to be a potential tool for studying the binding abilities of the bound compound. In this article, we present a methodology for the deconvolution of the total retention into structure-specific contributions. Three complementary silica-based CMSPs were prepared: 1) non-modified silica, 2) silica modified by syn-bis-Tröger's base (a molecular tweezer) and 3) silica modified by anti-bis-Tröger's base (a non-tweezer molecule). These were characterized by elemental analysis and Raman spectroscopy, and used to assemble liquid chromatography (LC) columns. The total retention factors were estimated for electron-deficient nitro- and cyano-derivatives of benzene in both normal and reverse elution modes. The total retention factor was considered to be the sum of structure-specific retention factors, each related to the affinity (the binding constant) of a specific structure (the binding site), and its content in the modified silica, as defined for weak-affinity chromatography (WAC). The obtained structure-specific contributions are in line with the binding studies of ligands in solution. They reveal details of the retention mechanism, suggesting a more suitable attachment of ligands, and expose the shortcomings of evaluations based solely on the total retentions.


Asunto(s)
Cromatografía Liquida/métodos , Dióxido de Silicio/química , Ligandos , Soluciones , Estereoisomerismo
13.
AAPS PharmSciTech ; 22(3): 118, 2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33782790

RESUMEN

The present study was designed to develop an efficient, safe, and patient-friendly dosage form, for oral delivery of alfa-choriogonadotropin, used in the treatment of female reproductive infertility. Silica-coated, saturated fatty acid (dipalmitoylphosphatidylcholine (DPPC))-engineered, nanolipidic vesicular (NLVs) system was developed for systemic delivery of therapeutic peptide, alfa-choriogonadotropin, through oral route. DPPC-based NLVs were formulated using the technique of thin-film hydration and were coated with silica to form a homogeneous surface silica shell. The formulated silica-coated NLVs were evaluated for physicochemical and physiologic stability under simulated conditions and were optimized based on physicochemical parameters like particle size, zeta potential, polydispersity index (PDI), entrapment efficiency, and in vitro release profile. Silica-coated, DPPC-based NLVs imparted physicochemical stability to entrapped alfa-choriogonadotropin against the biological environment prevailing in the human gastrointestinal tract (GIT). In vivo, subchronic animal toxicity studies were performed to assess the safety of the designed dosage form. Results of in vitro characterization and in vivo pharmacokinetic studies of fabricated formulation revealed that the silica-coated, DPPC-based NLV formulation was not only stable in human GIT but was also as efficacious as a marketed parenteral formulation for the systemic delivery of alfa-choriogonadotropin. In vivo toxicity studies revealed that silica-coated NLVs did not alter hematological and serum biochemical parameters. The histopathological studies also depicted no macroscopic changes in major organs; thus, the developed formulation was proven to be nontoxic and equally efficient as a marketed parenteral formulation for the delivery of alfa-choriogonadotropin with added benefits of possible self-medication, more patient acceptability, and no chances of infection.


Asunto(s)
Gonadotropina Coriónica/administración & dosificación , Gonadotropina Coriónica/química , Ácidos Grasos/química , Lípidos/química , Sustancias para el Control de la Reproducción/administración & dosificación , Sustancias para el Control de la Reproducción/química , Dióxido de Silicio/química , 1,2-Dipalmitoilfosfatidilcolina/química , Administración Oral , Animales , Gonadotropina Coriónica/toxicidad , Portadores de Fármacos , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Masculino , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley , Sustancias para el Control de la Reproducción/toxicidad
14.
J Chromatogr A ; 1643: 462069, 2021 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-33784503

RESUMEN

The present work reports on the preparation of polythiol-functionalized silica particles by thermally and photo-initiated radical addition reactions using poly(3-mercaptopropyl)methylsiloxane (PMPMS) as sulfhydryl group-rich surface modification reagent. Prior to surface modification with PMPMS, the silica was vinylized with vinyl trimethoxysilane. Finally, the usefulness of the thiolated silica particles was demonstrated by their further modification for various HPLC applications such as argentation chromatography and chiral separations. Aiming at a sulfhydryl group-rich, thin PMPMS layer on the surface of the silica several factors such as quantity of PMPMS, radical starter and reaction time were investigated by a design of experiment (DoE) approach. In thermally induced polymerization reactions 2,2'-azobis(isobutyronitrile) (AIBN) was used as radical starter, in photo-induced reactions 2,2-dimethoxy-2-phenylacetophenone (DMPA) was used instead. The incorporation of PMPMS was evaluated by elemental analysis and reactive and accessible sulfhydryl groups were determined by performing a thiol-disulfide exchange reaction with 2,2'-dipyridyl disulfide (DPDS). Consequently, thiol-functionalized silica particles (200 Å, 5 µm) with 1.81 ± 0.07 µmol sulfhydryl groups per m2 were prepared and further functionalized for silver ion chromatography and chiral separation chromatography clearly proving its utility as platform for further silica functionalization. The fabricated stationary phase for silver ion chromatography showed promising separation abilities for fatty acid methyl esters (FAME) according to the amount of double bonds within the fatty acid residue and cis- and trans-stilbene as model molecule for cis-trans isomerism. After the successful incorporation of O-tert-butylcarbamoyl quinine (tBuCQN) as chiral selector via thiol-ene click chemistry onto the PMPMS layer, the obtained chiral stationary phases (CSP) showed good separation of derivatized amino acids in polar organic elution mode comparable with a column based on commercially available CHIRALPAK QN-AX silica particles (120 Å, 5 µm).


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromatografía por Intercambio Iónico/métodos , Dióxido de Silicio/química , Siliconas/química , Concentración de Iones de Hidrógeno , Plata/química , Estereoisomerismo , Compuestos de Sulfhidrilo/química , Propiedades de Superficie
15.
Carbohydr Polym ; 261: 117847, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33766343

RESUMEN

Surface functionalization of mesoporous silica nanoparticles (MSNs) has been proposed as an efficient strategy for enhancing the biocompatibility and efficiency of an MSN-based carrier platform. Herein, natural polyelectrolyte multilayers composed of poly-l-ornithine (PLO) and carboxymethyl lentinan (LC) were coated on the surface of MSNs through a layer-by-layer (LbL) self-assembly technique, and were characterized by ζ-potential, FTIR, 13C NMR, SEM, TEM, XRD, and TG. The prepared carrier presented alternating positive and negative potentials when coated with the polyelectrolytes, and the surface of MSN-PLO/LC was rougher compared to the naked MSNs. The biocompatibility tests, including cytocompatibility, hemocompatibility, and histocompatibility, showed that MSNs biocompatibility could be improved by modifying LC. A high loading and sustained release drug delivery system was constructed after loading doxorubicin (DOX) into the prepared MSN-PLO/LC, which exhibited significant anti-proliferative efficiency in human cervical cancer cell lines (Hela). Therefore, the PLO/LC LbL NPs (layer-by-layer self-assembled nanoparticles coated with PLO/LC layers) based on MSNs, which is easily prepared by electrostatic interactions, can be considered a promising drug chemotherapeutic platform and delivery technique for future human cervical cancer therapy.


Asunto(s)
Antineoplásicos/administración & dosificación , Portadores de Fármacos , Lentinano , Animales , Antineoplásicos/farmacocinética , Células Cultivadas , Portadores de Fármacos/síntesis química , Portadores de Fármacos/química , Portadores de Fármacos/uso terapéutico , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Femenino , Células HeLa , Humanos , Lentinano/análogos & derivados , Lentinano/síntesis química , Lentinano/química , Lentinano/uso terapéutico , Masculino , Ensayo de Materiales , Ratones , Nanopartículas/química , Nanopartículas/uso terapéutico , Polimerizacion , Polímeros/síntesis química , Polímeros/química , Polímeros/uso terapéutico , Porosidad , Conejos , Dióxido de Silicio/química , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Carbohydr Polym ; 261: 117893, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33766378

RESUMEN

Glycosylated pH-sensitive mesoporous silica nanoparticles (MSNs) of capecitabine (CAP) were developed for targeting colorectal cancer. The MSNs possessed an average pore diameter of 8.12 ± 0.43 nm, pore volume of 0.73 ± 0.21 cm3/g, and particle size of 245.24 ± 5.75 nm. A high loading of 180.51 ± 5.23 mg/g attributed to the larger pore volume was observed. The surface of the drug-loaded MSNs were capped with chitosan-glucuronic acid (CHS-GCA) conjugate to combine two strategies viz. pH-sensitive, and lectin receptor mediated uptake. In vitro studies demonstrated a pH-sensitive and controlled release of CAP which was further enhanced in the presence of rat caecal content. Higher uptake of the (CAP-MSN)CHS-GCA was observed in HCT 116 cell lines. The glycosylated nanoparticles revealed reduction in the tumors, aberrant crypt foci, dysplasia and inflammation, and alleviation in the toxic features. This illustrated that the nanoparticles showed promising antitumor efficacy with reduced toxicity and may be used as a effective carrier against cancer.


Asunto(s)
Capecitabina/administración & dosificación , Quitosano/química , Neoplasias Colorrectales/tratamiento farmacológico , Portadores de Fármacos/síntesis química , Ácido Glucurónico/química , Dióxido de Silicio/química , Animales , Capecitabina/farmacocinética , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Materiales Biocompatibles Revestidos/síntesis química , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/uso terapéutico , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Preparaciones de Acción Retardada/síntesis química , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/uso terapéutico , Portadores de Fármacos/química , Portadores de Fármacos/uso terapéutico , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Femenino , Células HCT116 , Humanos , Concentración de Iones de Hidrógeno , Nanopartículas/química , Nanopartículas/uso terapéutico , Tamaño de la Partícula , Porosidad , Ratas , Ratas Wistar , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Carbohydr Polym ; 261: 117905, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-33766383

RESUMEN

Development of hybrid materials with molecular structure of organic-inorganic co-network is a promising method to enhance the stability and mechanical properties of biopolymers. Chitosan-silica hybrid nanocomposite scaffolds loaded with mangiferin, a plant-derived active compound possessing several bioactivities, were fabricated using the sol-gel synthesis and the freeze-drying processes. Investigation on the physicochemical and mechanical properties of the fabricated scaffolds showed that their properties can be improved and tailored by the formation of 3-dimensional crosslinked network and the addition of ZnO nanoparticles. The scaffolds possessed porosity, fluid uptake, morphology, thermal properties and mechanical strength suitable for bone tissue engineering application. Investigation on the biomineralization and cell viability indicated that the inclusion of bioactive mangiferin further promote potential use of the hybrid nanocomposite scaffolds in guided bone regeneration application.


Asunto(s)
Materiales Biocompatibles/síntesis química , Quitosano/química , Dióxido de Silicio/química , Andamios del Tejido/química , Xantonas/administración & dosificación , Animales , Materiales Biocompatibles/química , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Materiales Biocompatibles Revestidos/síntesis química , Materiales Biocompatibles Revestidos/química , Ensayo de Materiales , Ratones , Nanocompuestos/química , Porosidad , Xantonas/farmacocinética
18.
Int J Nanomedicine ; 16: 2107-2121, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33737808

RESUMEN

Purpose: Although anti-programmed cell death protein 1 antibody (aPD1) immunotherapy and chemotherapy has made much progress in the treatment of melanoma, the efficacy still needs to be further improved. Methods: Cancer treatment has been greatly enhanced by the use of nanotechnology. Cancer cell membrane (CCM)-camouflaged nanoparticles have shown promising potential in tumor therapy due to their excellent homologous-targeting ability, long blood circulation and immune escape. This work presents a biocompatible and tumor acidic environmental responsive CCM-camouflaged mesoporous silica nanoparticle (CMSN) that is loaded with dacarbazine (DTIC) and combined with aPD1 to achieve better antitumor efficacy. Results: In vitro cell experiments demonstrated that DTIC@CMSN exhibits a better anti-tumor killing efficiency and a stronger ability to promote the apoptosis of tumor cells than free DTIC. In vivo antitumor results demonstrated that combination therapy of DTIC@CMSN chemotherapy and aPD1 immunotherapy remarkably suppress the melanoma growth and prolong survival time due to highly selective tumor killing, activation of tumor-specific T cells, and regulation of the immunosuppressive tumor microenvironment. In addition, safety evaluation studies of DTIC@CMSN also demonstrate their increased tumor accumulation and decreased systemic toxicity. Conclusion: This study provides a promising nano-platform for the combination of chemotherapy with immunotherapy, which is potentially useful for the treatment of melanoma.


Asunto(s)
Antineoplásicos/farmacología , Membrana Celular/patología , Nanopartículas/química , Dióxido de Silicio/química , Microambiente Tumoral/efectos de los fármacos , Animales , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Terapia Combinada , Dacarbazina/farmacología , Dacarbazina/uso terapéutico , Humanos , Melanoma Experimental/tratamiento farmacológico , Melanoma Experimental/inmunología , Melanoma Experimental/patología , Ratones Endogámicos C57BL , Tamaño de la Partícula , Porosidad , Electricidad Estática
19.
AAPS PharmSciTech ; 22(3): 108, 2021 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-33718989

RESUMEN

The combination of self-microemulsifying drug delivery system (SMEDDS) and mesoporous silica materials favors the oral delivery of poorly water-soluble drugs (PWSD). However, the influence of the surface property of the mesopores towards the drug release and in vivo pharmacokinetics is still unknown. In this study, SBA-15 with hydroxyl groups (SBA-15-H), methyl groups (SBA-15-M), amino groups (SBA-15-A), or carboxyl groups (SBA-15-C) was combined with SMEDDS containing sirolimus (SRL). The diffusion and self-emulsifying of SMEDDS greatly improved the drug release over the raw SRL and SRL-SBA-15-R (R referred to as the functional groups). Results of drug absorption and X-ray photoelectron spectroscopy (XPS) showed strong hydrogen binding between SRL and the amino groups of SBA-15-A, which hindered the drug release and oral bioavailability of SRL-SMEDDS-SBA-15-A. The favorable release of SRL-SMEDDS-SBA-15-C (91.31 ± 0.57%) and SRL-SMEDDS-SBA-15-M (91.76 ± 3.72%) contributed to enhancing the maximum blood concentration (Cmax) and the area under the concentration-time curve (AUC0→48). In conclusion, the release of SRL-SMEDDS-SBA-15-R was determined by the surface affinity of the SBA-15-R and the interaction between the SRL molecules and the surface of SBA-15-R. This study suggested that the SMEDDS-SBA-15 was a favorable carrier for PWSD, and the surface property of the mesopores should be considered for the optimization of the SMEDDS-SBA-15.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/fisiología , Absorción Intestinal/fisiología , Sirolimus/administración & dosificación , Sirolimus/farmacocinética , Administración Oral , Animales , Antibacterianos/administración & dosificación , Antibacterianos/química , Antibacterianos/farmacocinética , Disponibilidad Biológica , Perros , Emulsiones/administración & dosificación , Emulsiones/química , Emulsiones/farmacocinética , Absorción Intestinal/efectos de los fármacos , Masculino , Dióxido de Silicio/administración & dosificación , Dióxido de Silicio/química , Dióxido de Silicio/farmacocinética , Sirolimus/química , Solubilidad , Propiedades de Superficie
20.
J Vis Exp ; (169)2021 03 12.
Artículo en Inglés | MEDLINE | ID: mdl-33779589

RESUMEN

A procedure for aesthetically enhancing silica aerogel monoliths by laser etching and incorporation of dyes is described in this manuscript. Using a rapid supercritical extraction method, large silica aerogel monolith (10 cm x 11 cm x 1.5 cm) can be fabricated in about 10 h. Dyes incorporated into the precursor mixture result in yellow-, pink- and orange-tinged aerogels. Text, patterns, and images can be etched onto the surface (or surfaces) of the aerogel monolith without damaging the bulk structure. The laser engraver can be used to cut shapes from the aerogel and form colorful mosaics.


Asunto(s)
Colorantes/química , Geles/química , Rayos Láser , Dióxido de Silicio/química , Dióxido de Silicio/efectos de la radiación
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