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1.
Int J Biol Macromol ; 199: 372-385, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-34998882

RESUMO

Polysaccharide nanocrystals have great potential to be used as improved drug carriers due to their low cost, high biodegradability, and biocompatibility. This study reports the synthesis of cellulose nanocrystals (CNC) loaded with 5-fluorouracil (CNC/5FU) to evaluate their anticancer activity against colorectal cancer cells. X-ray and Fourier-transform infrared spectroscopy demonstrated that acid hydrolysis successfully degraded the amorphous cellulose to liberate the crystal regions. From transmission electron microscopy, CNC/5FU appeared as rod-like nanocrystals with an average length and width of 69.53 ± 1.14 nm and 8.13 ± 0.72 nm, respectively. The anticancer drug 5FU showed improved thermal stability after being loading onto CNC. From UV-vis spectroscopy data, the drug encapsulation efficiency in CNC/5FU was estimated to be 83.50 ± 1.52%. The drug release of CNC/5FU was higher at pH 7.4 compared to those at pH 4.2 and 1.2. From the cytotoxicity assays, CNC did not affect the viability of CCD112 colon normal cells. On the other hand, CNC/5FU exhibited anticancer effects against HCT116 and HT-29 colorectal cancer cells. The anticancer actions of CNC/5FU against HCT116 cells were then confirmed using an in vitro tumor-on-chip model and clonogenic assay. Mechanistic studies demonstrated that CNC/5FU killed the cancer cells by mainly inducing cell apoptosis and mitochondrial membrane damage. Overall, this study indicated that CNC/5FU could be a potential nanoformulation for improved drug delivery and colorectal cancer treatment.


Assuntos
Neoplasias Colorretais , Nanopartículas , Celulose/química , Neoplasias Colorretais/tratamento farmacológico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Humanos , Nanopartículas/química
2.
Int J Nanomedicine ; 15: 5417-5432, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801697

RESUMO

INTRODUCTION: Green-based materials have been increasingly studied to circumvent off-target cytotoxicity and other side-effects from conventional chemotherapy. MATERIALS AND METHODS: Here, cellulose fibers (CF) were isolated from rice straw (RS) waste by using an eco-friendly alkali treatment. The CF network served as an anticancer drug carrier for 5-fluorouracil (5-FU). The physicochemical and thermal properties of CF, pure 5-FU drug, and the 5-FU-loaded CF (CF/5-FU) samples were evaluated. The samples were assessed for in vitro cytotoxicity assays using human colorectal cancer (HCT116) and normal (CCD112) cell lines, along with human nasopharyngeal cancer (HONE-1) and normal (NP 460) cell lines after 72-hours of treatment. RESULTS: XRD and FTIR revealed the successful alkali treatment of RS to isolate CF with high purity and crystallinity. Compared to RS, the alkali-treated CF showed an almost fourfold increase in surface area and zeta potential of up to -33.61 mV. SEM images illustrated the CF network with a rod-shaped structure and comprised of ordered aggregated cellulose. TGA results proved that the thermal stability of 5-FU increased within the drug carrier. Based on UV-spectroscopy measurements for 5-FU loading into CF, drug loading encapsulation efficiency was estimated to be 83 ±0.8%. The release media at pH 7.4 and pH 1.2 showed a maximum drug release of 79% and 46%, respectively, over 24 hours. In cytotoxicity assays, CF showed almost no damage, while pure 5-FU killed most of the both normal and cancer cells. Impressively, the drug-loaded sample of CF/5-FU at a 250 µg/mL concentration demonstrated a 58% inhibition against colorectal cancer cells, but only a 23% inhibition against normal colorectal cells. Further, a 62.50 µg/mL concentration of CF/5FU eliminated 71% and 39% of nasopharyngeal carcinoma and normal nasopharyngeal cells, respectively. DISCUSSION: This study, therefore, showed the strong potential anticancer activity of the novel CF/5-FU formulations, warranting their further investigation.


Assuntos
Celulose/química , Portadores de Fármacos/química , Fluoruracila/administração & dosagem , Fluoruracila/farmacologia , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Fluoruracila/farmacocinética , Células HCT116 , Humanos , Neoplasias Nasofaríngeas/tratamento farmacológico , Oryza/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
3.
Int J Nanomedicine ; 15: 2935-2945, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32425525

RESUMO

BACKGROUND: New anticancer agents that rely on natural/healthy, not synthetic/toxic, components are very much needed. METHODS: Ricinoleyl hydroxamic acid (RHA) was synthesized from castor oil and hydroxylamine using Lipozyme TL IM as a catalyst. To optimize the conversion, the effects of the following parameters were investigated: type of organic solvent, period of reaction, amount of enzyme, the molar ratio of reactants and temperature. The highest conversion was obtained when the reaction was carried out under the following conditions: hexane as a solvent; reaction period of 48 hours; 120 mg of Lipozyme TL IM/3 mmol oil; HA-oil ratio of 19 mmol HA/3 mmol oil; and temperature of 40°C. The cytotoxicity of the synthesized RHA was assessed using human dermal fibroblasts (HDF), and its application towards fighting cancer was assessed using melanoma and glioblastoma cancer cells over a duration of 24 and 48 hours. RESULTS: RHA was successfully synthesized  and it demonstrated strong anticancer activity against glioblastoma and melanoma cells at as low as a 1 µg/mL concentration while it did not demonstrate any toxicity against HDF cells. CONCLUSION: This is the first report on the synthesis of RHA with great potential to be used as a new anticancer agent.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Óleo de Rícino/química , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Catálise , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Hexanos/química , Humanos , Hidroxilamina/química , Lipase/química , Lipase/metabolismo , Melanoma/tratamento farmacológico , Melanoma/patologia , Solventes/química
4.
Int J Nanomedicine ; 15: 1005-1020, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32103953

RESUMO

PURPOSE: The aim of this study was to prepare zeolite/iron (III) oxide nanocomposites (zeolite/Fe2O3-NCs) as a smart fertilizer to improve crop yield and soil productivity. METHODS: Zeolite/Fe2O3-NCs were successfully produced by loading of Fe2O3-NPs onto the zeolite surface using a quick green precipitation method. The production of zeolite/Fe2O3 nanocomposites was performed under a mild condition using environmentally friendly raw materials as a new green chemistry method. The product was characterized using several techniques such as near and far Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction (PXRD), energy-dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). RESULTS: The results confirmed the formation of Fe2O3-NPs with mean particle sizes of 1.45, 2.19, and 2.20 nm on the surface of the zeolite per amount of 4, 7 and 12 wt% Fe2O3-NPs, respectively. Such results indicated that the size of the Fe2O3-NPs did not significantly change when Fe amounts increased from 7 to 12 wt% for the zeolite/Fe2O3-NCs. In terms of medical applications, in vitro cell studies demonstrated that zeolites and zeolite/Fe2O3-NCs were generally non-toxic to human fibroblast cells and significantly pernicious to human malignant melanoma cells. From MTS cytotoxicity assays, the concentration of Fe2O3 within the zeolite/Fe2O3-NCs that was effective at inhibiting the growth of malignant melanoma cells by 50% (the IC50 value) was ~14.9 wt%. The three types of nanocomposites were further tested as an iron smart nanofertilizer for the slow-release of iron ions. CONCLUSION: Advantages of this project include the production of non-toxic nanocomposites as a smart fertilizer to develop crops while the reaction involves the use of commercial and natural materials as low-cost raw materials with low energy usage due to a mild reaction condition, as well as the use of an environmentally friendly solvent (water) with no toxic residues.


Assuntos
Compostos Férricos/química , Fertilizantes , Nanocompostos/química , Zeolitas/química , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Fertilizantes/toxicidade , Fibroblastos/efeitos dos fármacos , Química Verde , Humanos , Ferro/farmacocinética , Melanoma/tratamento farmacológico , Melanoma/patologia , Microscopia Eletrônica de Transmissão , Nanocompostos/toxicidade , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
5.
Nanoscale ; 12(4): 2268-2291, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31942896

RESUMO

Infections are the main reason why most people die from burns and diabetic wounds. The clinical challenge for treating wound infections through traditional antibiotics has been growing steadily and has now reached a critical status requiring a paradigm shift for improved chronic wound care. The US Centers for Disease Control have predicted more deaths from antimicrobial-resistant bacteria than from all types of cancers combined by 2050. Thus, the development of new wound dressing materials that do not rely on antibiotics is of paramount importance. Currently, incorporating nanoparticles into scaffolds represents a new concept of 'nanoparticle dressing' which has gained considerable attention for wound healing. Silver nanoparticles (Ag-NPs) have been categorized as metal-based nanoparticles and are intriguing materials for wound healing because of their excellent antimicrobial properties. Ag-NPs embedded in wound dressing polymers promote wound healing and control microorganism growth. However, there have been several recent disadvantages of using Ag-NPs to fight infections, such as bacterial resistance. This review highlights the therapeutic approaches of using wound dressings functionalized with Ag-NPs and their potential role in revolutionizing wound healing. Moreover, the physiology of the skin and wounds is discussed to place the use of Ag-NPs in wound care into perspective.


Assuntos
Bandagens , Nanopartículas Metálicas/química , Prata/farmacologia , Dermatopatias/microbiologia , Animais , Infecções Bacterianas/prevenção & controle , Proliferação de Células , Farmacorresistência Bacteriana , Escherichia coli , Humanos , Hidrogéis , Teste de Materiais , Camundongos , Coelhos , Ratos , Pele/microbiologia , Dermatopatias/prevenção & controle , Staphylococcus aureus , Cicatrização
6.
Int J Nanomedicine ; 14: 1633-1657, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30880970

RESUMO

Conventional cancer treatment techniques show several limitations including low or no specificity and consequently a low efficacy in discriminating between cancer cells and healthy cells. Recent nanotechnology developments have introduced smart and novel therapeutic nanomaterials that take advantage of various targeting approaches. The use of nanotechnology in medicine and, more specifically, drug delivery is set to spread even more rapidly than it has over the past two decades. Currently, many nanoparticles (NPs) are under investigation for drug delivery including those for cancer therapy. Targeted nanomaterials bind selectively to cancer cells and greatly affect them with only a minor effect on healthy cells. Gold nanoparticles (Au-NPs), specifically, have been identified as significant candidates for new cancer therapeutic modalities because of their biocompatibility, easy functionalization and fabrication, optical tunable characteristics, and chemophysical stability. In the last decade, there has been significant research on Au-NPs and their biomedical applications. Functionalized Au-NPs represent highly attractive and promising candidates for drug delivery, owing to their unique dimensions, tunable surface functionalities, and controllable drug release. Further, iron oxide NPs due to their "superparamagnetic" properties have been studied and have demonstrated successful employment in numerous applications. In targeted drug delivery systems, drug-loaded iron oxide NPs can accumulate at the tumor site with the aid of an external magnetic field. This can lead to incremental effectiveness in drug release to the tumor site and vanquish cancer cells without harming healthy cells. In order for the application of iron oxide NPs in the human body to be realized, they should be biodegradable and biocompatible to minimize toxicity. This review illustrates recent advances in the field drug and small molecule delivery such as fluorouracil, folic acid, doxorubicin, paclitaxel, and daunorubicin, specifically when using gold and iron oxide NPs as carriers of anticancer therapeutic agents.


Assuntos
Sistemas de Liberação de Medicamentos , Ouro/química , Ferro/química , Nanopartículas Metálicas/química , Tamanho da Partícula , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Humanos
7.
Int J Nanomedicine ; 12: 2957-2978, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28442906

RESUMO

This review discusses the impact of green and environmentally safe chemistry on the field of nanotechnology-driven drug delivery in a new field termed "green nanomedicine". Studies have shown that among many examples of green nanotechnology-driven drug delivery systems, those receiving the greatest amount of attention include nanometal particles, polymers, and biological materials. Furthermore, green nanodrug delivery systems based on environmentally safe chemical reactions or using natural biomaterials (such as plant extracts and microorganisms) are now producing innovative materials revolutionizing the field. In this review, the use of green chemistry design, synthesis, and application principles and eco-friendly synthesis techniques with low side effects are discussed. The review ends with a description of key future efforts that must ensue for this field to continue to grow.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Química Verde/métodos , Nanomedicina/métodos , Nanopartículas/química , Humanos , Nanotecnologia/métodos , Nanotubos de Carbono/química , Extratos Vegetais/química , Polímeros/química
8.
Int J Mol Sci ; 13(2): 2148-2159, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22408444

RESUMO

Liquid-liquid iron(III) extraction was investigated using benzyl fatty hydroxamic acids (BFHAs) and methyl fatty hydroxamic acids (MFHAs) as chelating agents through the formation of iron(III) methyl fatty hydroxamate (Fe-MFHs) or iron(III) benzyl fatty hydroxamate (Fe-BFHs) in the organic phase. The results obtained under optimized conditions, showed that the chelating agents in hexane extract iron(III) at pH 1.9 were realized effectively with a high percentage of extraction (97.2% and 98.1% for MFHAs and BFHAs, respectively). The presence of a large amount of Mg(II), Ni(II), Al(III), Mn(II) and Co(II) ions did affect the iron(III) extraction. Finally stripping studies for recovering iron(III) from organic phase (Fe-MFHs or Fe-BFHs dissolved in hexane) were carried out at various concentrations of HCl, HNO(3) and H(2)SO(4). The results showed that the desired acid for recovery of iron(III) was 5 M HCl and quantitative recovery of iron(III) was achieved from Fe(III)-MFHs and Fe(III)-BFHs solutions in hexane containing 5 mg/L of Fe(III).


Assuntos
Compostos de Benzil/química , Ácidos Hidroxâmicos/química , Quelantes de Ferro/química , Ferro/isolamento & purificação , Extração Líquido-Líquido/métodos , Óleos de Plantas/química , Alcanos/química , Clorofórmio/química , Compostos Férricos/química , Heptanos/química , Hexanos/química , Concentração de Íons de Hidrogênio , Íons , Óleo de Palmeira , Xilenos/química
9.
Molecules ; 16(8): 6634-44, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-25134767

RESUMO

Fatty hydroxamic acid derivatives were synthesized using Lipozyme TL IM catalyst at biphasic medium as the palm kernel oil was dissolved in hexane and hydroxylamine derivatives were dissolved in water: (1) N-methyl fatty hydroxamic acids (MFHAs); (2) N-isopropyl fatty hydroxamic acids (IPFHAs) and (3) N-benzyl fatty hydroxamic acids (BFHAs) were synthesized by reaction of palm kernel oil and N-methyl hydroxylamine (N-MHA), N-isopropyl hydroxylamine (N-IPHA) and N-benzyl hydroxylamine (N-BHA), respectively. Finally, after separation the products were characterized by color testing, elemental analysis, FT-IR and 1H-NMR spectroscopy. For achieving the highest conversion percentage of product the optimum molar ratio of reactants was obtained by changing the ratio of reactants while other reaction parameters were kept constant. For synthesis of MFHAs the optimum mol ratio of N-MHA/palm kernel oil = 6/1 and the highest conversion was 77.8%, for synthesis of IPFHAs the optimum mol ratio of N-IPHA/palm kernel oil = 7/1 and the highest conversion was 65.4% and for synthesis of BFHAs the optimum mol ratio of N-BHA/palm kernel oil = 7/1 and the highest conversion was 61.7%.


Assuntos
Ácidos Graxos/síntese química , Ácidos Hidroxâmicos/síntese química , Lipase/metabolismo , Óleos de Plantas/química , Elementos Químicos , Óleo de Palmeira , Espectroscopia de Prótons por Ressonância Magnética , Espectroscopia de Infravermelho com Transformada de Fourier
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