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1.
Sci Rep ; 14(1): 4373, 2024 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388553

RESUMEN

Cancer therapy necessitates the development of novel and effective treatment modalities to combat the complexity of this disease. In this project, we propose a synergistic approach by combining chemo-photothermal treatment using gold nanorods (AuNRs) supported on thiol-functionalized mesoporous silica, offering a promising solution for enhanced lung cancer therapy. To begin, mesoporous MCM-41 was synthesized using a surfactant-templated sol-gel method, chosen for its desirable porous structure, excellent biocompatibility, and non-toxic properties. Further, thiol-functionalized MCM-41 was achieved through a simple grafting process, enabling the subsequent synthesis of AuNRs supported on thiol-functionalized MCM-41 (AuNR@S-MCM-41) via a gold-thiol interaction. The nanocomposite was then loaded with the anticancer drug doxorubicin (DOX), resulting in AuNR@S-MCM-41-DOX. Remarkably, the nanocomposite exhibited pH/NIR dual-responsive drug release behaviors, facilitating targeted drug delivery. In addition, it demonstrated exceptional biocompatibility and efficient internalization into A549 lung cancer cells. Notably, the combined photothermal-chemo therapy by AuNR@S-MCM-41-DOX exhibited superior efficacy in killing cancer cells compared to single chemo- or photothermal therapies. This study showcases the potential of the AuNR@S-MCM-41-DOX nanocomposite as a promising candidate for combined chemo-photothermal therapy in lung cancer treatment. The innovative integration of gold nanorods, thiol-functionalized mesoporous silica, and pH/NIR dual-responsive drug release provides a comprehensive and effective therapeutic approach for improved outcomes in lung cancer therapy. Future advancements based on this strategy hold promise for addressing the challenges posed by cancer and transforming patient care.


Asunto(s)
Neoplasias Pulmonares , Nanotubos , Humanos , Terapia Fototérmica , Neoplasias Pulmonares/tratamiento farmacológico , Oro/química , Doxorrubicina , Dióxido de Silicio/química , Fototerapia , Nanotubos/química
2.
Vet Med Sci ; 7(6): 2135-2143, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34388307

RESUMEN

The present study was designed to compare the effects of lidocaine and ropivacaine in intravenous regional anaesthesia (IVRA) in dogs. Twelve adult male dogs were used. Under isoflurane anaesthesia, exsanguination was performed in the target forelimb. Then, a blood pressure cuff was encircled around the limb proximal to the elbow joint with a pressure of approximately 150 mmHg above the mean arterial blood pressure. The animals then received one of the two treatments of lidocaine (3 mg/kg) or ropivacaine (1.5 mg/kg) with a final volume of 0.6 mL/kg into the cephalic vein. After 60 min, the anaesthesia was disrupted and the tourniquet was removed using intermittent opening (30 s) and closing (5 min) manner for three times. The results revealed that at 20 and 30 min after the initiation of IVRA, the dogs in ROP showed higher analgesia than LID. A leakage under the tourniquet during IVRA was detected. Tremor and hypersalivation were observed after tourniquet removal in some dogs. It was concluded that ropivacaine might provide a higher quality of anaesthesia than lidocaine in IVRA in dogs. The development of local anaesthetic toxicity is a major concern and should be considered at the time of tourniquet removal.


Asunto(s)
Anestesia de Conducción , Lidocaína , Anestesia de Conducción/veterinaria , Anestesia Intravenosa/métodos , Anestesia Intravenosa/veterinaria , Anestésicos Locales/efectos adversos , Animales , Perros , Lidocaína/efectos adversos , Masculino , Ropivacaína
3.
Food Chem ; 314: 126179, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31968292

RESUMEN

In this study, for the first time, hollow fiber and monolithic fiber were fabricated based on metal-organic framework deep eutectic solvents/molecularly imprinted polymers (MOF- DES/MIPs) and were used for microextraction of phthalate esters under termed hollow fiber liquid membrane-protected solid-phase microextraction (HFLMP-SPME) followed by gas chromatography- flame ionization detection. Several parameters influencing extraction recoveries of phthalate esters including adsorption and desorption parameters were investigated and optimized using fabricated MOF- DES/MIPs monolithic fiber. Under optimal conditions, detection limits (S/N = 3) of the method were in a range of 0.008-0.03 µg L-1 and limits of quantification (S/N = 10) were between 0.028 and 0.12 µg L-1. RSD (%) for intra-day and inter-day precisions were between 2.4-4.7% and 2.6-3.4%, respectively. Subsequently, this procedure was successfully applied with satisfactory results in the determination of phthalate esters in yogurt, water, and soybean oil samples. The R (%) ranged from 95.5 to 100.0% in different samples.


Asunto(s)
Estructuras Metalorgánicas/química , Impresión Molecular/métodos , Microextracción en Fase Sólida/métodos , Aceite de Soja/química , Agua/química , Yogur/análisis , Adsorción , Cromatografía de Gases , Ésteres/química , Límite de Detección , Impresión Molecular/instrumentación , Ácidos Ftálicos/química , Polímeros/química , Microextracción en Fase Sólida/instrumentación , Solventes/química
4.
Mikrochim Acta ; 186(3): 129, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30707301

RESUMEN

A method is described for multiple monolithic fiber solid-phase microextraction of five sterol and steroid hormones from complex food samples. A composite was prepared from graphene oxide, a metal-organic framework (ZIF-8) and a molecularly imprinted polymers was deposited on a single thin fiber. Four thin fibers were combined to obtain a fiber bundle. The nanocomposite was characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy. The parameters affecting the extraction were optimized by Box-Behnken design. Following elution with methanol, the analytes progesterone, testosterone, ß-sitosterol, cholesterol and campesterol were quantified via HPLC. Response is linear in the 0.01-1000 µg L-1 concentration range, and limits of detection range from 3 to 5 ng L-1. The method was successfully applied to the determination of the five analytes in spiked samples of white meat, egg yolks and vegetables. The relative mean recoveries ranged from 95.0% to 101.0%. Graphical abstract Schematic presentation of a monolith molecularly imprinting polymer (MIP) fiber fabrication for solid phase microextraction (SPME) of sterol and steroid hormones. The fiber was synthesis using graphene oxide and metal-organic framework, ZIF-8, composite by imprinting technique and progesterone as template. Four fibers were combined to obtain a fiber bundle. Then, multiple fiber solid-phase microextraction was employed for determination of analytes by coupling with HPLC/UV detection.

5.
Ultrason Sonochem ; 50: 239-250, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30274892

RESUMEN

The magnetic Ni-Ag bimetallic nanoparticles supported on reduced graphene oxide (Ni-Ag NPs/rGO) was synthesized and characterized by transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), field emission scanning electron microscopy (FE-SEM) and vibrating sample magnetometer (VSM). Subsequently, this magnetic hybrid material as a novel adsorbent was applied for the sonochemical simultaneous removal of sunset yellow and tartrazine dyes in combination with first-order derivative spectrophotometric method to resolve the overlap between the spectra of these dyes. With magnetic properties, the adsorbent could easily be collected from aqueous solution using an external magnetic field. The parameters including initial concentration of each dye, adsorbent dosage and sonication time were studied by Box-Behnken design (BBD) and response surface methodology (RSM), while pH was studied by one-at-a-time approach. According to Box-Behnken design based on desirability function (DF), the best experimental conditions was set as initial sunset yellow concentration 10 mgL-1, initial tartrazine concentration 8.5 mgL-1, adsorbent dosage 0.045 g and sonication time of 15 min. The equilibrium data was fitted to different isotherm models and the results revealed the suitability of the Langmuir model. The maximum sorption capacity calculated from the Langmuir model was 28.57 and 26.31 mg g-1 for sunset yellow and tartrazine, respectively. Kinetic data revealed that the adsorption process followed a pseudo-second-order model. The reusability of the magnetite nanoparticles revealed about 8% decrease in the removal efficiency within four consecutive runs.

6.
Ultrason Sonochem ; 40(Pt A): 101-112, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28946397

RESUMEN

In this research, a sensitive, simple and rapid ultrasound assisted dispersive micro solid-phase extraction (USAD-µSPE) was developed using a synthesized core-shell magnetic mesoporous nanocomposite (Fe3O4@nSiO2@mSiO2-NH2) as an efficient adsorbent for the preconcentration and spectrofluorometric determination of ofloxacin (OFL) in biological samples. The synthesized adsorbent was characterized using FT-IR spectroscopy, transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), energy dispersive X-ray (EDX) spectroscopy, thermogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET) analysis. The application of this magnetic nanocomposite as a sensitive solid phase for removal, preconcentration and spectrofluorometric quantification of trace amount of OFL was developed. Influence of various variables including pH, sorbent dosage, desorption solvent properties and sonication time on present method response was studied and optimized. The results showed that using the proposed method OFL can be determined in the linear concentration range of 1.0-500.0µgL-1 with a limit of detection as low as 0.21µgL-1 and relative standard deviation less than 2.5 (%). The results of human urine and blood plasma analysis showed that the method is a good candidate for biological sample analysis purposes.


Asunto(s)
Nanopartículas de Magnetita/química , Nanocompuestos/química , Ofloxacino/sangre , Ofloxacino/orina , Dióxido de Silicio/química , Microextracción en Fase Sólida/métodos , Ondas Ultrasónicas , Adsorción , Humanos , Concentración de Iones de Hidrógeno , Ofloxacino/química , Ofloxacino/aislamiento & purificación , Porosidad , Espectrometría de Fluorescencia , Factores de Tiempo
7.
J Pharm Biomed Anal ; 122: 98-109, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26852159

RESUMEN

A molecularly imprinted polymer (MIP) fiber on stainless steel wire using ciprofloxacin template with a mild template removal condition was synthetized and evaluated for fiber solid phase microextraction (SPME) of fluoroquinolones (FQs) from biological fluids and pharmaceutical samples, followed by high performance liquid chromatography analysis with UV detection (HPLC-UV). The developed MIP fiber exhibited high selectivity for the analytes in complex matrices. The coating of the fibers were inspected using fourier transform infrared spectrophotometry, thermogaravimetric analysis, energy dispersive X-ray (EDX) spectroscopy as well as by scanning electron microscopy (SEM). The fiber shows high thermal stability (up to 300°C), good reproducibility and long lifetime. The composite coating did not swell in organic solvents nor did it strip off from the substrate. It was also highly stable and extremely adherent to the surface of the stainless steel fiber. The fabricated fiber exclusively exhibited excellent extraction efficiency and selectivity for some FQs. The effective parameters influencing the microextraction efficiency such as pH, extraction time, desorption condition, and stirring rate were investigated. Under optimized conditions, the limits of detection of the four FQs ranged from 0.023-0.033 µg L(-1) (S/N=5) and the calibration graphs were linear in the concentration range from 0.1-40 µg L(-1), the inter-day and intraday relative standard deviations (RSD) for various FQs at three different concentration level (n=5) using a single fiber were 1.1-4.4% and the fiber to fiber RSD% (n=5) was 4.3-6.7% at 5 µg L(-1) of each anlyetes. The method was successfully applied for quantification of FQs in real samples including serum, plasma and tablet formulation with the recoveries between 97 to 102%.


Asunto(s)
Líquidos Corporales/química , Ciprofloxacina/química , Fluoroquinolonas/química , Polímeros/química , Acero Inoxidable/química , Comprimidos/análisis , Comprimidos/química , Química Farmacéutica/métodos , Cromatografía Líquida de Alta Presión/métodos , Impresión Molecular/métodos , Reproducibilidad de los Resultados , Microextracción en Fase Sólida/métodos , Espectrofotometría Ultravioleta/métodos , Tecnología Farmacéutica/métodos
8.
Food Chem ; 188: 30-6, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26041160

RESUMEN

A novel ultrasound-assisted back extraction reverse micelles coupled with gas chromatography-flame ionization detection has been developed for the extraction and determination of some short chain aldehydes in different heated edible oil samples. After the homogenization of the oil samples with Triton X-100, 200 µL of methanol was added to facilitate the phase separation. The aqueous micelle phase has been separated by centrifugation, then it was treated with a mixture of H2O: CHCl3 and ultrasonic vibration, were used to effectively back-extraction of the analytes into the chloroform phase. The sedimented organic phase was obtained after centrifugation, withdrawn into the microsyringe and directly injected into the GC-FID system. The calibration graphs were linear in the range 0.05-20 mg L(-1). The limits of detection were in the range of 0.02-0.15 mg L(-1). This procedure was successfully applied for determination of propanal, butanal, hexanal and heptanal in real heated oil samples.


Asunto(s)
Aldehídos/química , Cromatografía de Gases/métodos , Ionización de Llama/métodos , Micelas , Aceites/química , Ultrasonido/métodos
9.
J Pharm Biomed Anal ; 44(1): 41-8, 2007 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-17324550

RESUMEN

The electrochemical behavior of piroxicam on a multi-walled carbon nanotubes electrode for the first time was investigated. A highly sensitive and fast responding sensor for determination of piroxicam was simply and conveniently fabricated. The constructed electrode exhibits efficiently catalytic activity for the electrooxidation of piroxicam at a reduced over potential with high sensitivity, stability, and long lifetime in the wide concentration rang of piroxicam. The oxidation process was found to be dependent on the pH of the supporting electrolyte. The behavior is further exploited as a sensitive detection method for piroxicam determination by differential pulse voltammetry. Under the optimized conditions the calibration plots are linear in the concentration range of 0.15-5 microg ml(-1). Application of the method for the determination of the drug in the dosage form (Feledene capsules and tablets and also piroxicam gel), without any interference, from the excipients, resulted in acceptable deviation from the stated concentrations. Recoveries were obtained in the range 96.35-104.16%. The detection limit of 0.1 microg ml(-1) was obtained for piroxicam determination.


Asunto(s)
Antiinflamatorios no Esteroideos/química , Electroquímica/métodos , Nanotubos de Carbono/química , Preparaciones Farmacéuticas/química , Piroxicam/química , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/análisis , Calibración , Cápsulas/análisis , Catálisis , Formas de Dosificación , Estabilidad de Medicamentos , Electroquímica/instrumentación , Electrodos , Excipientes/análisis , Geles/análisis , Concentración de Iones de Hidrógeno , Estructura Molecular , Oxidación-Reducción , Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/análisis , Piroxicam/administración & dosificación , Piroxicam/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Comprimidos/análisis
10.
Anal Sci ; 18(3): 329-32, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11918194

RESUMEN

A method for sensitive and selective determination of silver based on the catalytic effect of silver(I) ion on the oxidation of Janus Green by peroxodisulfate is described. o-Phenanthroline is used as an activator. The rate of the decrease in absorbance of Janus Green (at 615 nm) is proportional to the concentration of silver in the range of 0.3-4.0 ng mL(-1) and 4.0-500.0 ng mL(-1). The theoretical limit of detection was 0.25 ng mL(-1). The method is free from most interferences. The method was applied to the determination of silver in plants (the uptake of silver by plants), in photographic solutions, lake water and several synthetic samples.

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