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1.
J Environ Manage ; 359: 121063, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38704955

RESUMO

Due to the potential harm caused by emerging micro-pollutants to living organisms, contaminating water supplies by micro-pollutants like EDCs, pharmaceuticals, and microorganisms has become a concern in many countries. Considering both microbiological and micro-pollutant exposure risks associated with water use for agricultural/or household purposes, it is imperative to create a strategy for improving pollutant removal from treated wastewater that is both effective and affordable. Natural clay minerals efficiently remove contaminants from wastewater, though the pristine clay has less affinity to several organic pollutants. Hydrophilic polymers, viz., poly(ethylene glycol) (PEG), improve the dispersion of particles, flocculation processes, and surface properties. In this study, PEG grafted with attapulgite, thereby providing a high-specific surface-area, mesoporous materials for the adsorption of micro-pollutants like ciprofloxacin (CIP) and 17α-ethinylestradiol (EE2) at high rates. A gentle washing process regenerates the clay-polymer material several times with no performance loss, and the natural water implications show fair applicability of solid in decontaminating the CIP and EE2 in an aqueous medium. Further, greenly synthesized silver nanoparticles in situ disperse with the clay polymer efficiently remove the gram-positive and gram-negative bacterium viz., Bacillus subtilis, and Pseudomonas aeruginosa, which are commonly persistent in aquatic environments. The clay polymer outperformed a modified clay composite to eliminate microorganisms and organic micro-pollutants in significant quantities quickly. These results clearly show the importance of fibrous clay-polymer composite for water purification technologies.


Assuntos
Argila , Polímeros , Prata , Purificação da Água , Purificação da Água/métodos , Polímeros/química , Argila/química , Prata/química , Adsorção , Poluentes Químicos da Água/química , Águas Residuárias/química , Bactérias
2.
Saudi Pharm J ; 32(6): 102096, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38757071

RESUMO

The aim of the current study was to explore the potential of human plasma-derived exosomes as versatile carriers for drug delivery by employing various active and passive loading methods. Exosomes were isolated from human plasma using differential centrifugation and ultrafiltration method. Drug loading was achieved by employing sonication and freeze thaw methods, facilitating effective drug encapsulation within exosomes for delivery. Each approach was examined for its effectiveness, loading efficiency and ability to preserve membrane stability. Methotrexate (MTX), a weak acid model drug was loaded at a concentration of 2.2 µM to exosomes underwent characterization using various techniques such as particle size analysis, transmission electron microscopy and drug loading capacity. Human plasma derived exosomes showed a mean size of 162.15 ± 28.21 nm and zeta potential of -30.6 ± 0.71 mV. These exosomes were successfully loaded with MTX demonstrated a better drug encapsulation of 64.538 ± 1.54 % by freeze thaw method in comparison 55.515 ± 1.907 % by sonication. In-vitro drug release displayed 60 % loaded drug released within 72 h by freeze thaw method that was significantly different from that by sonication method i.e., 99 % within 72 h (p value 0.0045). Moreover, cell viability of exosomes loaded by freeze thaw method was significantly higher than that by sonication method (p value 0.0091) suggested that there was membrane disruption by sonication method. In conclusion, this study offers valuable insights into the potential of human plasma-derived exosomes loaded by freeze thaw method suggest as a promising carrier for improved drug loading and maintenance of exosomal membrane integrity.

3.
Cancer Immunol Immunother ; 72(7): 2127-2135, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36828963

RESUMO

INTRODUCTION: Immune checkpoint inhibitors (ICIs) became the standard of care for several solid tumors. A limited fraction of patients (pts) achieves a long-term benefit. Plasmatic and intracellular cholesterol levels have emerged as promising biomarkers. The aim of the present study was to determine whether cholesterol efflux capacity (CEC), mediated by serum transporters (ABCA1 and ABCG1) and passive diffusion (PD), impacts on clinical outcome of advanced non-small cell lung cancer (NSCLC) and metastatic renal cell carcinoma (mRCC) pts treated with ICIs. MATERIAL AND METHODS: We retrospectively enrolled advanced NSCLC and mRCC pts consecutively treated with ICIs between October 2013 and October 2018. CEC and cholesterol loading capacity (CLC) were assessed by well-established specific cell models. As primary endpoint, CEC, PD and CLC were correlated with overall survival (OS) while the effects of these parameters on progression-free survival (PFS) and clinical benefit (CB), defined as complete/partial response or stable disease, represented secondary endpoints. RESULTS: NSCLC accounted for 94.2% of 70 enrolled cases, and serum sample suitable for CEC and PD determination was available in 68. Blood cholesterol and serum ABCA1, ABCG1, PD and CLC were associated with outcomes (OS, PFS and CB) at univariate analysis. At the multivariate analysis, only PD confirmed its positive prognostic value in terms of OS, PFS and CB. CONCLUSION: The favorable impact of cholesterol PD on clinical outcome might reflect its main conformation in mature HDL particles which potentially shape an inflamed context, ultimately promoting ICI efficacy. Further prospective studies are needed to support our findings and uncover targetable pathways.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Renais , Neoplasias Renais , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Estudos Retrospectivos , Carcinoma de Células Renais/tratamento farmacológico , Biomarcadores Tumorais/análise , Neoplasias Renais/tratamento farmacológico , Colesterol
4.
Rheumatology (Oxford) ; 62(3): 1254-1263, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35809057

RESUMO

OBJECTIVE: Excessive cholesterol accumulation in macrophages is the pivotal step underlying atherosclerotic plaque formation. We here explore factors in the serum of patients with RA, and mechanisms through which they interact with and influence cholesterol loading capacity (CLC) of macrophages. METHODS: In a cross-sectional observational cohort of 104 patients with RA, CLC was measured as intracellular cholesterol content in human THP-1-derived macrophages after incubation with patient serum. Low-density lipoprotein (LDL) oxidation was measured in terms of oxidized phospholipids on apoB100-containing particles (oxPL-apoB100). Antibodies against oxidized LDL (anti-oxLDL), proprotein convertase subtilisin/Kexin type-9 (PCSK9) and high-sensitivity CRP were also quantified. All analyses adjusted for atherosclerotic cardiovascular disease (ASCVD) risk score, obesity, total LDL, statin use, age at diagnosis, and anti-oxLDL IgM. RESULTS: OxPL-apoB100, anti-oxLDL IgG and PCSK9 were positively associated with CLC (all P < 0.020). OxPL-apoB100 directly influenced CLC only in dual RF- and ACPA-positive patients [unstandardized b (95% bootstrap CI)=2.08 (0.38, 3.79)]. An indirect effect of oxPL-apoB100 on CLC through anti-oxLDL IgG increased, along with level of CRP [index of moderated mediation = 0.55 (0.05-1.17)]. CRP also moderated yet another indirect effect of oxPL-apoB100 on CLC through upregulation of PCSK9, but only among dual-seropositive patients [conditional indirect effect = 0.64 (0.13-1.30)]. CONCLUSION: Oxidized LDL can directly influence CLC in dual-seropositive RA patients. Two additional and independent pathways-via anti-oxLDL IgG and PCSK9-may mediate the effects of oxPL-apoB100 on CLC, depending on CRP and seropositivity status. If externally validated, these findings may have clinical implications for cardiovascular risk prevention.


Assuntos
Artrite Reumatoide , Aterosclerose , Humanos , Pró-Proteína Convertase 9 , Proteína C-Reativa/metabolismo , Estudos Transversais , Lipoproteínas LDL/metabolismo , Colesterol/metabolismo , Macrófagos/metabolismo , Aterosclerose/metabolismo , Imunoglobulina G/metabolismo
5.
Nanotechnology ; 34(41)2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37413979

RESUMO

Dendritic fibrous nano silica (DFNS) represents an optimal carrier material for pesticide constituents, due to its radial accessibility channels and high specific surface area. A low-energy methodology for synthesizing DFNS at a low volume ratio of oil to water is provided by employing 1-pentanol as the oil solvent in the microemulsion synthesis system, renowned for its remarkable stability and exceptional solubility. The DFNS@KM nano-pesticide was fabricated using a diffusion supported loading (DiSupLo) method and kresoxim-methyl (KM) as the template drug. Findings from Fourier-transform infrared spectroscopy, XRD, thermogravimetric, differential thermal analysis, and Brunauer-Emmet-Teller analyzes revealed the physical adsorption of KM onto the synthesized DFNS without any chemical bonding, with KM mainly existing in an amorphous state within the channels. High-performance liquid chromatography measurements demonstrated that only the loading amount of DFNS@KM was primarily dependent on the KM to DFNS ratio, with minimal effects observed from loading temperature and time. The loading amount and encapsulation efficiency of DFNS@KM were found to be 63.09% and 84.12%, respectively. Furthermore, DFNS effectively prolonged the release of KM, with a cumulative release rate of 85.43% over 180 h. The successful loading of pesticide components into DFNS synthesized with a low oil-to-water ratio provides theoretical support for the industrialization of nano-pesticides, with significant implications for enhancing pesticide utilization, reducing pesticide dosage, augmenting agricultural efficiency, and promoting sustainable agricultural development.

6.
J Environ Manage ; 335: 117578, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36863146

RESUMO

This investigation provides a reproducible approach for determining the limits of an upflow anaerobic sludge blanket (UASB) reactor designed for the methanization of the liquid fraction of fruit and vegetable waste (FVWL). Two identical mesophilic UASB reactors were operated for 240 days with a three-day fixed hydraulic retention time and an organic load rate (OLR) increased from 1.8 to 10 gCOD L-1 d-1. Because of the previous estimation of flocculent-inoculum methanogenic activity, it was possible to design a safe OLR for the quick start-up of both UASB reactors. The operational variables obtained from the operation of the UASB reactors did not show statistical differences, ensuring the experiment's reproducibility. As a result, the reactors achieved methane yield close to 0.250 LCH4 gCOD-1 up to the OLR of 7.7 gCOD L-1 d-1. Furthermore, the maximum volumetric methane production rate of 2.0 LCH4 L-1 d-1 was discovered for the OLR ranges between 7.7 and 10 gCOD L-1 d-1. The possible overload at OLR of 10 gCOD L-1 d-1 resulted in a significant reduction of methane production in both UASB reactors. Based on the methanogenic activity of the UASB reactors sludge, a maximum loading capacity of approximately 8 gCOD L-1 d-1 was estimated.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Anaerobiose , Eliminação de Resíduos Líquidos/métodos , Verduras , Frutas , Reprodutibilidade dos Testes , Metano , Reatores Biológicos
7.
Molecules ; 27(12)2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35744978

RESUMO

Biopolymers, especially polysaccharides (e.g., gum Arabic), are widely applied as drug carriers in drug delivery systems due to their advantages. Curcumin, with high antioxidant ability but limited solubility and bioavailability in the body, can be encapsulated in gum Arabic to improve its solubility and bioavailability. When curcumin is encapsulated in gum Arabic, it is essential to understand how it works in various conditions. As a result, in Simulated Intestinal Fluid and Simulated Gastric Fluid conditions, we investigated the potential of gum Arabic as the drug carrier of curcumin. This study was conducted by varying the gum Arabic concentrations, i.e., 5, 10, 15, 20, 30, and 40%, to encapsulate 0.1 mg/mL of curcumin. Under both conditions, the greater the gum Arabic concentration, the greater the encapsulation efficiency and antioxidant activity of curcumin, but the worse the gum Arabic loading capacity. To achieve excellent encapsulation efficiency, loading capacity, and antioxidant activity, the data advises that 10% is the best feasible gum Arabic concentration. Regarding the antioxidant activity of curcumin, the findings imply that a high concentration of gum Arabic was effective, and the Simulated Intestinal Fluid brought an excellent surrounding compared to the Simulated Gastric Fluid solution. Moreover, the gum Arabic releases curcumin faster in the Simulated Gastric Fluid condition.


Assuntos
Curcumina , Antioxidantes , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Goma Arábica
8.
Angew Chem Int Ed Engl ; 61(22): e202117679, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35257450

RESUMO

Two-dimensional nanomaterials are attracting attention for cancer therapy. However, high toxicity, insensitivity to external stimuli and single therapeutic modality are still key issues hindering their clinical application. Therefore, the construction of a safe, intelligent and versatile nanocomposite is needed to meet clinical expectations. Herein, we developed a nanocomposite of Bi@RP-PEG-DOX with 2D bismuthene loaded with 0D red phosphorus quantum dots and DOX. The nanocomposite with DOX loading capacity (ca. 250 %) and photothermal conversion efficiency (ca. 54 %) showed both photothermal and photodynamic effects and a sensitive response of drug release to the acidic tumor microenvironment or NIR II laser irradiation. The nanocomposite exhibits good biosafety. Through the X-ray attenuation properties of bismuth, the nanocomposite serves as an excellent CT contrast agent, providing potential to perform CT-guided therapy.


Assuntos
Nanocompostos , Nanopartículas , Neoplasias , Pontos Quânticos , Linhagem Celular Tumoral , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Fósforo , Fototerapia/métodos , Medicina de Precisão
9.
Mar Drugs ; 19(8)2021 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-34436309

RESUMO

Refined cobia liver oil is a nutritional supplement (CBLO) that is rich in polyunsaturated fatty acids (PUFAs), such as DHA and EPA; however, PUFAs are prone to oxidation. In this study, the fabrication of chitosan-TPP-encapsulated CBLO nanoparticles (CS@CBLO NPs) was achieved by a two-step method, including emulsification and the ionic gelation of chitosan with sodium tripolyphosphate (TPP). The obtained nanoparticles were inspected by dynamic light scattering (DLS) and showed a positively charged surface with a z-average diameter of between 174 and 456 nm. Thermogravimetric analysis (TGA) results showed the three-stage weight loss trends contributing to the water evaporation, chitosan decomposition, and CBLO decomposition. The loading capacity (LC) and encapsulation efficiency (EE) of the CBLO loading in CS@CBLO NPs were 17.77-33.43% and 25.93-50.27%, respectively. The successful encapsulation of CBLO in CS@CBLO NPs was also confirmed by the Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques. The oxidative stability of CBLO and CS@CBLO NPs was monitored by FTIR. As compared to CBLO, CS@CBLO NPs showed less oxidation with a lower generation of hydroperoxides and secondary oxidation products after four weeks of storage. CS@CBLO NPs are composed of two ingredients that are beneficial for health, chitosan and fish oil in a nano powdered fish oil form, with an excellent oxidative stability that will enhance its usage in the functional food and pharmaceutical industries.


Assuntos
Antioxidantes/química , Quitosana/química , Óleos de Peixe/química , Peixes , Animais , Organismos Aquáticos , Composição de Medicamentos , Nanopartículas , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
10.
J Microencapsul ; 38(7-8): 559-571, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34637365

RESUMO

AIM: The present study aimed to develop liposomal Rhein by employing a hydrophobic ion-pairing technique (HIP) for improved pancreatitis therapy. METHODS: F127 modified liposomal Rhein (F127-RPC-Lip) was prepared using a two-step process consisting of complexation first, followed by a film-ultrasonic dispersion step. The drug-phospholipid interaction was characterised by FT-IR and P-XRD. Particle size and morphology were investigated using DLS and TEM, respectively. Biodistribution and therapeutic efficacy of F127-RPC-Lip were evaluated in a rat model of acute pancreatitis. RESULTS: F127-RPC-Lip achieved efficient drug encapsulation after complexation with lipids through non-covalent interactions and had an average hydrodynamic diameter of about 141 nm. F127-RPC-Lip demonstrated slower drug release (55.90 ± 3.60%, w/w) than Rhein solution (90.27 ± 5.11%) within 24 h. Compared with Rhein, F127-RPC-Lip exhibited prolonged systemic circulation time, superior drug distribution, and attenuated injury in the pancreas of rats post-injection. CONCLUSIONS: HIP-assembled liposomes are a promising strategy for Rhein in treating pancreatitis.


Assuntos
Lipossomos , Pancreatite , Doença Aguda , Animais , Antraquinonas , Pancreatite/tratamento farmacológico , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Distribuição Tecidual
11.
Molecules ; 26(9)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067007

RESUMO

As film-forming agents, fillers and adsorbents, microplastics are often added to daily personal care products. Because of their chemical stability, they remain in the environment for thousands of years, endangering the safety of the environment and human health. Therefore, it is urgent to find an environmentally friendly substitute for microplastics. Using n-octyltrimethoxysilane (OTMS) and tetraethoxysilane (TEOS) as silicon sources, a novel, environmentally friendly, organic hollow mesoporous silica system is designed with a high loading capacity and excellent adsorption characteristics in this work. In our methodology, sandalwood essential oil (SEO) was successfully loaded into the nanoparticle cavities, and was involved in the formation of Pickering emulsion as well, with a content of up to 40% (w/w). The developed system was a stable carrier for the dispersion of SEO in water. This system can not only overcome the shortcomings of poor water solubility and volatility of sandalwood essential oil, but also act as a microplastic substitute with broad prospects in the cosmetics and personal care industry, laying a foundation for the preparation and applications of high loading capacity microcapsules in aqueous media.


Assuntos
Portadores de Fármacos/química , Óleos Voláteis/química , Compostos Orgânicos/química , Óleos de Plantas/química , Sesquiterpenos/química , Dióxido de Silício/química , Cápsulas , Emulsões , Espectroscopia Fotoeletrônica , Porosidade , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Vibração , Água/química
12.
Zhongguo Zhong Yao Za Zhi ; 46(13): 3356-3363, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34396755

RESUMO

With Sangtang Yin granule as model drug,and based on the strategy of " unification of medicines and excipients",the feasibility of preparing high drug loading granules with traditional Chinese medicine( TCM) raw powder as carrier was explored. The powder yield,particle size and particle size distribution,fillibility,flowability,hygroscopicity,reconstituability and other key physical properties relating to preparations of 8 herbs( Dioscoreae Rhizoma,Euryales Semen,Atractylodis Macrocephalae Rhizoma,Coicis semen,Poria,Puerariae Lobatae Radix,Puerariae Thomsonii Radix and Coicis Semen by stir-frying with bran) were studied after being smashed,and the feasibility of taking them as excipients of TCM granules was evaluated by co-spray drying,dry granulation and other preparation techniques. According to the results of the physical properties of raw powders,raw powders of Dioscoreae Rhizoma,Euryales Semen and Puerariae Thomsonii Radix had a high powder yield,uniform particle size distribution,good fillibility,poor hygroscopicity and good reconstitutability,with the feature of assisting granule forming. Compared with the prescription of spray dry powder Sangtang Yin without any excipient,the co-sprayed powder had a high yield,good fillibility and compressibility. The yield of dry granules prepared by co-spraying dry powder was increased by more than 10%,and the particles had a uniform color,good fluidity and dissolubility with the drug-loading rate up to 100%. Based on the physical characteristics of TCM raw powder combined with the analysis of the preparation process,Dioscoreae Rhizoma and Puerariae Thomsonii Radix raw powder were selected as the carriers of granule preparations,and Sangtang Yin granule without any excipient was successfully prepared. The findings provide a feasible idea for the preparation of TCM granules with a high drug loading capacity.


Assuntos
Medicina Tradicional Chinesa , Pueraria , Excipientes , Tamanho da Partícula , Pós , Rizoma
13.
Mol Pharm ; 16(7): 2858-2871, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31136710

RESUMO

Liposomes are widely used for systemic delivery of chemotherapeutic agents to reduce their nonspecific side effects. Gemcitabine (Gem) makes a great candidate for liposomal encapsulation due to the short half-life and nonspecific side effects; however, it has been difficult to achieve liposomal Gem with high drug loading capacity. Remote loading, which uses a transmembrane pH gradient to induce an influx of drug and locks the drug in the core as a sulfate complex, does not serve Gem as efficiently as doxorubicin (Dox) due to the low p Ka value of Gem. Existing studies have attempted to improve Gem loading capacity in liposomes by employing lipophilic Gem derivatives or creating a high-concentration gradient for active loading into the hydrophilic cores (small volume loading). In this study, we combine the remote loading approach and small volume loading or hypertonic loading, a new approach to induce the influx of Gem into the preformed liposomes by high osmotic pressure, to achieve a Gem loading capacity of 9.4-10.3 wt % in contrast to 0.14-3.8 wt % of the conventional methods. Liposomal Gem showed a good stability during storage, sustained-release over 120 h in vitro, enhanced cellular uptake, and improved cytotoxicity as compared to free Gem. Liposomal Gem showed a synergistic effect with liposomal Dox on Huh7 hepatocellular carcinoma cells. A mixture of liposomal Gem and liposomal Dox delivered both drugs to the tumor more efficiently than a free drug mixture and showed a relatively good anti-tumor effect in a xenograft model of hepatocellular carcinoma. This study shows that bioactive liposomal Gem with high drug loading capacity can be produced by remote loading combined with additional approaches to increase drug influx into the liposomes.


Assuntos
Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Desoxicitidina/análogos & derivados , Sistemas de Liberação de Medicamentos/métodos , Neoplasias Hepáticas/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Composição de Medicamentos , Liberação Controlada de Fármacos , Quimioterapia Combinada , Humanos , Lipossomos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Nus , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
14.
Int J Hyperthermia ; 36(1): 104-114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30428737

RESUMO

PURPOSE: Although magnetite nanoparticles (MNPs) are promising agents for hyperthermia therapy, insufficient drug encapsulation efficacies inhibit their application as nanocarriers in the targeted drug delivery systems. In this study, porous magnetite nanoparticles (PMNPs) were synthesized and coated with a thermosensitive polymeric shell to obtain a synergistic effect of hyperthermia and chemotherapy. MATERIALS AND METHODS: PMNPs were produced using cetyltrimethyl ammonium bromide template and then coated by a polyethylene glycol layer with molecular weight of 1500 Da (PEG1500) and phase transition temperature of 48 ± 2 °C to endow a thermosensitive behavior. The profile of drug release from the nanostructure was studied at various hyperthermia conditions generated by waterbath, magnetic resonance-guided focused ultrasound (MRgFUS), and alternating magnetic field (AMF). The in vitro cytotoxicity and hyperthermia efficacy of the doxorubicin-loaded nanoparticles (DOX-PEG1500-PMNPs) were assessed using human lung adenocarcinoma (A549) cells. RESULTS: Heat treatment of DOX-PEG1500-PMNPs containing 235 ± 26 mg·g-1 DOX at 48 °C by waterbath, MRgFUS, and AMF, respectively led to 71 ± 4%, 48 ± 3%, and 74 ± 5% drug release. Hyperthermia treatment of the A549 cells using DOX-PEG1500-PMNPs led to 77% decrease in the cell viability due to the synergistic effects of magnetic hyperthermia and chemotherapy. CONCLUSION: The large pores generated in the PMNPs structure could provide a sufficient space for encapsulation of the chemotherapeutics as well as fast drug encapsulation and release kinetics, which together with thermosensitive characteristics of the PEG1500 shell, make DOX-PEG1500-PMNPs promising adjuvants to the magnetic hyperthermia modality.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Hipertermia Induzida/métodos , Nanopartículas de Magnetita/química , Polietilenoglicóis/química , Humanos , Campos Magnéticos
15.
Mol Pharm ; 13(1): 251-61, 2016 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-26568134

RESUMO

Identification of the usefulness of lipid-based formulations (LBFs) for delivery of poorly water-soluble drugs is at date mainly experimentally based. In this work we used a diverse drug data set, and more than 2,000 solubility measurements to develop experimental and computational tools to predict the loading capacity of LBFs. Computational models were developed to enable in silico prediction of solubility, and hence drug loading capacity, in the LBFs. Drug solubility in mixed mono-, di-, triglycerides (Maisine 35-1 and Capmul MCM EP) correlated (R(2) 0.89) as well as the drug solubility in Carbitol and other ethoxylated excipients (PEG400, R(2) 0.85; Polysorbate 80, R(2) 0.90; Cremophor EL, R(2) 0.93). A melting point below 150 °C was observed to result in a reasonable solubility in the glycerides. The loading capacity in LBFs was accurately calculated from solubility data in single excipients (R(2) 0.91). In silico models, without the demand of experimentally determined solubility, also gave good predictions of the loading capacity in these complex formulations (R(2) 0.79). The framework established here gives a better understanding of drug solubility in single excipients and of LBF loading capacity. The large data set studied revealed that experimental screening efforts can be rationalized by solubility measurements in key excipients or from solid state information. For the first time it was shown that loading capacity in complex formulations can be accurately predicted using molecular information extracted from calculated descriptors and thermal properties of the crystalline drug.


Assuntos
Lipídeos/química , Preparações Farmacêuticas/química , Química Farmacêutica , Simulação por Computador , Solubilidade
16.
Mol Pharm ; 13(8): 2782-6, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27414996

RESUMO

A nanoscale cationic porous drug carrier ZJU-101 (ZJU = Zhejiang University), synthesized by the solvothermal method to get the crystal size of ∼300 nm, was used to load diclofenac sodium, an anionic drug. This positively charged host materials showed a large loading capacity of diclofenac sodium (∼0.546 g/g) through ion exchange and penetration procedures. The drug delivery in the inflamed tissues (pH = 5.4) exhibited a more effective release in comparison with that in the normal tissues (pH = 7.4), demonstrating a physiological pH responsive drug release. This discriminating drug release process was controlled by anion exchange between anions in phosphate buttered saline (PBS) and coordinated/free diclofenac anions.


Assuntos
Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Animais , Cátions/química , Linhagem Celular Tumoral , Diclofenaco/química , Liberação Controlada de Fármacos , Concentração de Íons de Hidrogênio , Microscopia Confocal , Ratos
17.
Mol Pharm ; 12(7): 2459-68, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-25988812

RESUMO

Strong associations between drug and polymeric carriers are expected to contribute to higher drug loading capacities and better physical stability of amorphous solid dispersions. However, molecular details of the interaction patterns and underlying mechanisms are still unclear. In the present study, a series of amorphous solid dispersions of clofazimine (CLF), an antileprosy drug, were prepared with different polymers by applying the solvent evaporation method. When using hypromellose phthalate (HPMCP) as the carrier, the amorphous solid dispersion system exhibits not only superior drug loading capacity (63% w/w) but also color change due to strong drug-polymer association. In order to further explain these experimental observations, the interaction between CLF and HPMCP was investigated in a nonpolar volatile solvent system (chloroform) prior to forming the solid dispersion. We observed significant UV/vis and (1)H NMR spectral changes suggesting the protonation of CLF and formation of ion pairs between CLF and HPMCP in chloroform. Furthermore, nuclear Overhauser effect spectroscopy (NOESY) and diffusion order spectroscopy (DOSY) were employed to evaluate the strength of associations between drug and polymers, as well as the molecular mobility of CLF. Finally, by correlating the experimental values with quantum chemistry calculations, we demonstrate that the protonated CLF is binding to the carboxylate group of HPMCP as an ion pair and propose a possible structural model of the drug-polymer complex. Understanding the drug and carrier interaction patterns from a molecular perspective is critical for the rational design of new amorphous solid dispersions.


Assuntos
Clofazimina/química , Polímeros/química , Química Farmacêutica/métodos , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Hansenostáticos/química , Metilcelulose/análogos & derivados , Metilcelulose/química , Solubilidade , Solventes/química
18.
J Food Sci Technol ; 52(12): 8068-76, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26604379

RESUMO

ß-carotene, a potent antioxidant, has been encapsulated and slow release (SR) formulations were prepared using laboratory synthesized poly(ethylene glycols) (PEGs) based functionalized amphiphilic copolymers. Encapsulation efficiency and loading capacity of the developed formulations were determined which ranged from 22.60 to 28.08 % and 2.2 to 2.8 % respectively. The release kinetics of ß-carotene from developed formulations in water revealed increased solubility and prolonged stability of ß-carotene. The formulations were further subjected to different pH conditions (viz., 1.8, 6.8 and 7.8) corresponding to human gastrointestinal tract to study the effect of pH on the release of ß-carotene. The diffusion exponent (n values) ranged from the 0.1540 to 0.2342 for developed formulation. The results showed that developed slow release formulations were unaffected by the highly acidic conditions referring to the gastric environment of human body. However, the release of ß-carotene was high at pH 7.8 and slightly higher at pH 6.8.

19.
Int J Biol Macromol ; 260(Pt 1): 129361, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38218280

RESUMO

Pectin is a promising nano-carrier. The degree of methyl esterification (DM) influences the physiochemical properties of pectin. However, the effect of DM on the encapsulation capacity of pectin remains unclear. In this work, low methyl-esterified pectin (LMP) and high methyl-esterified pectin (HMP) were prepared. The molecular weight, rheological properties of these pectins with various DM levels were determined. Then icaritin/pectin micelles (IPMs) were prepared using HMP and LMP. Notably, higher loading capacities (18.75-20.12 %) were observed in HMP-IPMs compared to LMP-IPMs (15.72-16.64 %). Furthermore, LMP-IPMs demonstrated a DM-dependent reduction in particle sizes, ranging from 449 to 527 nm. In contrast, the particle sizes of HMP-IPMs varied between 342 and 566 nm, with smaller particle sizes observed in HMP-IPMs at higher DM levels. A significant positive correlation was found between DM and the formation of IPMs, including encapsulation efficiency, loading capacity, Zeta potential, and polydispersity index. Alkali de-esterification showed a weak impact on the pectin structure. Hydroxyl groups like 7-OH and 5-OH of icaritin might be involved in the formation of IPMs. The hydrogen-bond interactions between pectin and icaritin could be enhanced as DM increased.


Assuntos
Flavonoides , Pectinas , Pectinas/química , Esterificação , Micelas
20.
Int J Pharm ; 656: 124128, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38621612

RESUMO

Metal-organic frameworks (MOFs) have shown excellent performance in the field of drug delivery. Despite the synthesis of a vast array of MOFs exceeding 100,000 varieties, certain formulations have exhibited suboptimal performance characteristics. Therefore, there is a pressing need to enhance their efficacy by identifying MOFs with superior drug loading capacities and minimal cytotoxicity, which can be achieved through machine learning (ML). In this study, a stacking regression model was developed to predict drug loading capacity and cytotoxicity of MOFs using datasets compiled from various literature sources. The model exhibited exceptional predictive capabilities, achieving R2 values of 0.907 for drug loading capacity and 0.856 for cytotoxicity. Furthermore, various model interpretation methods including partial dependence plots, individual conditional expectation, Shapley additive explanation, decision tree, random forest, CatBoost Regressor, and light gradient-boosting machine were employed for feature importance analysis. The results revealed that specific metal atoms such as Zn, Cr, Fe, Zr, and Cu significantly influenced the drug loading capacity and cytotoxicity of MOFs. Through model validation encompassing experimental validation and computational verification, the reliability of the model was thoroughly established. In general, it is a good practice to use ML methods for predicting drug loading capacity and cytotoxicity analysis of MOFs, guiding the development of future property prediction methods for MOFs.


Assuntos
Aprendizado de Máquina , Estruturas Metalorgânicas , Estruturas Metalorgânicas/química , Humanos , Sobrevivência Celular/efeitos dos fármacos , Algoritmos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos
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