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1.
Int J Biol Macromol ; 260(Pt 2): 129546, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38246461

RESUMEN

Present investigation deals with the synthesis of psyllium based copolymeric hydrogels and evaluation of their physiochemical and biomedical properties. These copolymers have been prepared by grafting of poly(vinyl phosphonic acid) (poly (VPA)) and poly(acrylamide) (poly(AAm)) onto psyllium in the presence of crosslinker N,N-methylene bis acrylamide (NNMBA). These copolymers [psyllium-poly(VPA-co-AAm)-cl-NNMBA] were characterized by field emission-scanning electron micrographs (FE-SEM), electron dispersion X-ray analysis (EDAX), Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), 13C-nuclear magnetic resonance (NMR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA)- differential thermal analysis (DTG). FESEM, AFM and XRD demonstrated heterogeneous morphology with a rough surface and an amorphous nature. Diffusion of ornidazole occurred with a non-Fickian diffusion mechanism, and the release profile data was fitted in the Korsemeyer-Peppas kinetic model. Biochemical analysis of hydrogel properties confirmed the blood-compatible nature during blood-polymer interactions and revealed haemolysis value 3.95 ± 0.05 %. The hydrogels exhibited mucoadhesive character during biomembrane-polymer interactions and demonstrated detachment force = 99.0 ± 0.016 mN. During 2,2-diphenyl-1-picrylhydrazyl reagent (DPPH) assay, free radical scavenging was observed 37.83 ± 3.64 % which illustrated antioxidant properties of hydrogels. Physiological and biomedical properties revealed that these hydrogels could be explored for drug delivery uses.


Asunto(s)
Acrilamida , Ácidos Fosforosos , Psyllium , Acrilamida/química , Psyllium/química , Hidrogeles/química , Acrilamidas/química , Polímeros/química , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Concentración de Iones de Hidrógeno
2.
Carbohydr Polym ; 302: 120377, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36604055

RESUMEN

In this study, a composite hydrogel with a low swelling ratio, excellent mechanical properties, and good U (VI) adsorption capacity was developed by incorporating a metal-organic framework (MOF) with a poly (acrylamide-co-acrylic acid)/chitosan (P(AM-co-AA)/CS) composite. The CS chain, which contains NH2, reduces the swelling ratio of the hydrogel to 4.17 after 5 h of immersion in water. The coordinate bond between the MOF and carboxyl group on the surface of P(AM-co-AA)/CS improves the mechanical properties and stability of P(AM-co-AA)/CS. The U(VI) adsorption capacity of P(AM-co-AA)/CS/MOF-808 is 159.56 mg g-1 at C0 = 99.47 mg L-1 and pH = 8.0. The adsorption process is well fitted by the Langmuir isotherm and pseudo-second-order model. The P(AM-co-AA)/CS/MOF-808 also exhibits good repeatability and stability after five adsorption-desorption cycles. The uranium adsorption capacity of the developed adsorbent after one month in natural seawater is 6.2 mg g-1, and the rate of uranium adsorption on the hydrogel is 0.21 mg g-1 day-1.


Asunto(s)
Quitosano , Estructuras Metalorgánicas , Uranio , Uranio/química , Quitosano/química , Hidrogeles/química , Concentración de Iones de Hidrógeno , Cinética , Agua de Mar/química , Acrilamidas/química , Adsorción
3.
Int J Biol Macromol ; 227: 241-251, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36539172

RESUMEN

In this paper, a kind of superabsorbent resin (SAR) with superior quality for hygiene products was developed using Fructus Aurantii Immaturus pectin (FAIP) from Citrus aurantium L.. FAIP-g-AM/AMPS SAR was established by free radical graft co-polymerization with FAIP as skeleton structure, N, N'-Methylene-bis (acrylamide) (MBA) as the cross-linker. Meanwhile, the functional monomers of acrylamide (AM) and 2-acrylamido-2-methylpropane sulfonic acid (AMPS) were introduced. The structure and morphology of FAIP-g-AM/AMPS were characterized by FTIR, 13C NMR, XRD, SEM and TG-DSC analysis. The results confirmed that the AFIP-g-AM/AMPS SAR was successfully prepared, which exhibited a three-dimensional (3D) network structure and an excellent thermal stability. The absorption and retention capacity of FAIP-g-AM/AMPS was comparable to or even better than commercial diapers and sanitary napkins. Significantly, FAIP-g-AM/AMPS itself exhibited excellent antibacterial and safety. FAIP-g-AM/AMPS has an inhibition ratio of 97.1 % for Escherichia coli (E. coli) and 98.5 % for Staphylococcus aureus (S. aureus), and was non-irritating and non-allergic to the skin. In addition, FAIP-g-AM/AMPS presented amazing biodegradability and a weight loss reached 37.1 % after 30 days by soil burial test. The research provides a safe and high-performance SAR, which expected to be used in hygiene products such as baby diapers, adult incontinence pads and sanitary napkins.


Asunto(s)
Pectinas , Staphylococcus aureus , Pectinas/farmacología , Escherichia coli , Antibacterianos/farmacología , Antibacterianos/química , Acrilamidas/química , Cloruro de Sodio , Acrilamida
4.
Biomed Chromatogr ; 35(12): e5232, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34424556

RESUMEN

The objective of this paper was to develop a preparative method for the separation and purification of phaseoloidin, entadamide A, and entadamide A-ß-D-glucopyranoside from the crude extract of Entada phaseoloides by high-speed countercurrent chromatography (HSCCC) for the first time. Optimized by orthogonal experiments, the extraction conditions were extraction temperature of 65°C, solid-to-liquid ratio of 1:15 (g/mL), ethanol concentration of 40%, and extraction time of 2.5 h. Using n-butanol-acetic acid-water (4:1:5, v/v/v) as the two-phase solvent system, 38.79 mg phaseoloidin (the purity was 99.3% with a recovery of 98.1%), 34.85 mg entadamide A (the purity was 96.4% with a recovery of 98.5%), and 33.97 mg entadamide A-ß-D-glucopyranoside (the purity was 98.6% with a recovery of 97.7%) were obtained from 500 mg crude extract by HSCCC in head-to-tail elution mode. The retention ratio of stationary phase was 51.0%. According to the antioxidant activity assays, phaseoloidin, entadamide A, and entadamide A-ß-D-glucopyranoside had certain scavenging abilities on 1,1-diphenyl-2-picrylhydrazyl free radicals and hydroxyl free radicals.


Asunto(s)
Acrilamidas , Distribución en Contracorriente/métodos , Fabaceae/química , Glucósidos , Extractos Vegetales/química , Acrilamidas/análisis , Acrilamidas/química , Acrilamidas/aislamiento & purificación , Antioxidantes/análisis , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo , Cromatografía Líquida de Alta Presión , Glucósidos/análisis , Glucósidos/química , Glucósidos/aislamiento & purificación , Picratos
5.
Int J Biol Macromol ; 182: 1820-1831, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34052272

RESUMEN

Developing a multifunctional wound dressing that protects, cures and indicates the healing progress, is a new approach of investigation. Red cabbage extract (RCE), consisting of bioactive compounds that have antioxidant, anti-inflammatory, anti-carcinogenic, bactericidal, antifungal, and antiviral activities, was utilized as a natural pH-sensitive indicator. Chitosan-based hydrogel, encapsulating RCE, was developed to obtain a smart therapeutic pH-sensitive wound dressing as antimicrobial bio-matrix provides a comfortable cushion for wound bed and indicates its status. Methacrylated-chitosan was crosslinked by different concentrations of methylenebisacrylamide (MBAA) by which hydrogel mechanical and morphological properties were tuned. The proposed mechanism for hydrogel formation was confirmed by FT-IR. The coloristic properties of the RCE and the changes in color intensity as a function of pH were confirmed by UV-Vis spectroscopy. The effect of MBAA on the mechanical, swelling, release and morphological properties of hydrogel were investigated. MBAA (2.5% wt/v) in 2% wt/v chitosan showed preferable mechanical (20 KPa), swelling (1294% at pH 8 ± 0.2), and release (prolonged up to 5 days) properties. Hydrogel matrices, loaded on cotton gauze submerged in different pH buffer solutions, showed explicit color changes from green to red as pH changed from 9 to 4.


Asunto(s)
Vendajes , Brassica/química , Quitosano/farmacología , Hidrogeles/farmacología , Extractos Vegetales/farmacología , Cicatrización de Heridas/efectos de los fármacos , Acrilamidas/química , Antocianinas/análisis , Quitosano/química , Colorimetría , Concentración de Iones de Hidrógeno , Fenómenos Mecánicos , Porosidad , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier
6.
Int J Mol Sci ; 22(5)2021 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-33800956

RESUMEN

Crosslinking of hydroxypropyl methyl cellulose (HPMC) and acrylic acid (AAc) was carried out at various compositions to develop a high-solid matrix with variable glass transition properties. The matrix was synthesized by the copolymerisation of two monomers, AAc and N,N'-methylenebisacrylamide (MBA) and their grafting onto HMPC. Potassium persulfate (K2S2O8) was used to initiate the free radical polymerization reaction and tetramethylethylenediamine (TEMED) to accelerate radical polymerisation. Structural properties of the network were investigated with Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), modulated differential scanning calorimetry (MDSC), small-deformation dynamic oscillation in-shear, thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The results show the formation of a cohesive macromolecular entity that is highly amorphous. There is a considerable manipulation of the rheological and calorimetric glass transition temperatures as a function of the amount of added acrylic acid, which is followed upon heating by an extensive rubbery plateau. Complementary TGA work demonstrates that the initial composition of all the HPMC-AAc networks is maintained up to 200 °C, an outcome that bodes well for applications of targeted bioactive compound delivery.


Asunto(s)
Acrilamidas/química , Derivados de la Hipromelosa/química , Acrilatos/química , Rastreo Diferencial de Calorimetría , Vidrio , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Polimerizacion , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Vitrificación , Difracción de Rayos X
7.
J Mater Chem B ; 8(46): 10637-10649, 2020 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-33147312

RESUMEN

Injectable hydrogels have been developed as biomedical materials in various fields but the biofouling on their surface limits applications in vivo. In this work, a zwitterionic structure was introduced into an injectable hydrogel based on thermosensitive nanogels to overcome the foreign body reaction. The hydrodynamic diameter of the resultant poly(N-isopropylacrylamide-co-sulfobetaine methacrylate) (PNS) nanogels was ca. 105 nm. The aqueous dispersion with a high content of PNS nanogels showed a flowable sol state at room temperature, and turned into a hydrogel in situ at ∼36 °C due to the thermosensitivity of the PNS nanogels. In particular, the resulting hydrogel exhibited lower biofouling both in vitro and in vivo in comparison with similar hydrogels without a zwitterionic structure. Polydopamine nanoparticles (PDA NPs) as a photothermal agent and an anti-tumour drug could be easily co-loaded in the injectable hydrogel. Under near-infrared (NIR) irradiation for 10 min, the temperature of the PNS system containing PDA NPs could reach ca. 38 °C. The drug release from the in situ-forming hydrogel could be accelerated by NIR laser irradiation, and showed a sustainable release behavior and adjustability. The results of intratumoral injection of the as-prepared injectable hydrogel containing PDA NPs and an anti-tumour drug showed significant anticancer effects combining photothermal therapy and local chemotherapy. This constructed injectable zwitterionic thermosensitive hydrogel is easy to use with the advantage of low-fouling and may become a promising platform for various biomedical applications.


Asunto(s)
Acrilamidas/administración & dosificación , Antineoplásicos/administración & dosificación , Betaína/análogos & derivados , Hidrogeles/administración & dosificación , Fototerapia/métodos , Acrilamidas/química , Acrilamidas/metabolismo , Adsorción , Animales , Antineoplásicos/química , Antineoplásicos/metabolismo , Betaína/administración & dosificación , Betaína/química , Betaína/metabolismo , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Terapia Combinada/métodos , Relación Dosis-Respuesta a Droga , Células Hep G2 , Humanos , Hidrogeles/química , Hidrogeles/metabolismo , Ratones , Carga Tumoral/efectos de los fármacos , Carga Tumoral/fisiología
8.
Mater Sci Eng C Mater Biol Appl ; 108: 110339, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31923981

RESUMEN

In this study a novel and smart multi-functional hydrogel (MFH) was synthesized from N, N dimethyl acrylamide (DMAAm), gelatin, citric acid (CA) and pomegranate extract (PE) for instant and easy monitoring of the color change in MFH due to changes in medium conditions such as pH and temperature. MFH was utilized as food packaging material, equipped with the developed properties. MFH was synthesized with a redox polymerization technique in film form on petri dishes. Mechanical and water resistance properties of MFH were improved by CA and N, N, methylenebisacrylamide, while PE was used to gain antimicrobial, antioxidant and anthocyanin properties. Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analyzer (TGA), Liquid Chromatography-Mass Spectroscopy (LC-MS/MS) and Scanning Electron Microscopy (SEM) instruments were utilized for characterization of MFH. FTIR revealed the existence of bonding interactions between the functional group of PE and gelatin, carbonyl groups of DMAAm and carboxylic acid groups of CA. TGA results indicate that MFH was stable up to 400 °C. Then the response of total antioxidant and anthocyanin activities leading to the color change in MFH were studied at different pH values. The color change in MFH was monitored even at very small pH changes in the medium. Moreover, antimicrobial activity and stability of MFH were investigated when it was tested in harsh environments and against Escherichia coli, Bacillus subtilis and Staphylococcus aureus on real samples of whole pasteurized milk and cheese for a 7-day period. It exhibited remarkable antimicrobial activity with pasteurized whole milk and cheese. It was concluded that MFH is a very good candidate to be used as biodegradable food packaging material.


Asunto(s)
Acrilamidas/química , Antiinfecciosos , Bacterias/crecimiento & desarrollo , Embalaje de Alimentos , Gelatina/química , Extractos Vegetales/química , Granada (Fruta)/química , Antiinfecciosos/síntesis química , Antiinfecciosos/química , Antiinfecciosos/farmacología
9.
Biomacromolecules ; 21(2): 613-620, 2020 02 10.
Artículo en Inglés | MEDLINE | ID: mdl-31841316

RESUMEN

Herein we report the synthesis of a cellulose-grafted bottlebrush copolymer with nucleobases as hydrophobic moieties. Well-defined spherical micelles from this bottlebrush copolymer were fabricated via a solvent switch method. A morphological transition from spheres to worms was only observed to occur when a diblock copolymer with a complementary nucleobase functionality was introduced. Hydrophobic interaction is not capable of triggering the morphological transformation, and the diblock copolymer with the heterogeneous acrylamide nucleobase monomer can induce the morphological transition at higher A:T molar ratios, which might be caused by the weak H-bonding interaction. This supramolecular "grafting to" method enables the preparation of a series of nanoparticles with similar shapes and dimensions but distinct surface properties such as zeta potentials. Moreover, reversible morphological transitions between worm-like micelles and spheres can be achieved using a reversible collapsing and swelling of a thermoresponsive polymer. This work highlights that a supramolecular "grafting to" approach between complementary nucleobases can be utilized to tune morphologies and surface properties of nanoparticles.


Asunto(s)
Adenina/química , Celulosa/química , Nanopartículas/química , Polímeros/química , Acrilamidas/química , Resinas Acrílicas/química , Enlace de Hidrógeno , Polímeros/síntesis química , Espectrofotometría Ultravioleta , Propiedades de Superficie , Timina/química
10.
Int J Parasitol Drugs Drug Resist ; 10: 109-117, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31472356

RESUMEN

Entamoeba histolytica and Giardia duodenalis are widespread intestinal protozoan parasites which both spread via cysts that have to be ingested to infect a new host. Their environment, the small intestine for G. duodenalis and the colon for E. histolytica, contains only very limited amounts of oxygen, so both parasites generate energy by fermentation and substrate level phosphorylation rather than by oxidative phosphorylation. They both contain reducing agents able to reduce and activate nitroimidazole drugs such as metronidazole which is the gold standard drug to treat Entamoeba or Giardia infections. Although metronidazole works well in the majority of cases, it has a number of drawbacks. In animal models, the drug has carcinogenic activity, and concerns about a possible teratogenic activity remain. In addition, the treatment of G. duodenalis infections is hampered by emerging metronidazole resistance. Plant-derived drugs play a dominant role in human medicine, therefore we tested the activity of 14 isolated plant compounds belonging to seven different classes in vitro against both parasites. The tests were performed in a new setting in microtiter plates under anaerobic conditions. The compound with the highest activity was methylgerambullin, a sulphur-containing amide found in Glycosmis species of the family Rutaceae with an EC50 of 14.5 µM (6.08 µg/ml) after 24 h treatment for E. histolytica and 14.6 µM (6.14 µg/ml) for G. duodenalis. The compound was successfully synthesised in the laboratory which opens the door for the generation of new derivatives with higher activity.


Asunto(s)
Acrilamidas/farmacología , Amidas/farmacología , Antiprotozoarios/farmacología , Entamoeba histolytica/efectos de los fármacos , Giardia lamblia/efectos de los fármacos , Extractos Vegetales/farmacología , Rutaceae/química , Compuestos de Azufre/farmacología , Acrilamidas/síntesis química , Acrilamidas/química , Amidas/síntesis química , Amidas/química , Antiprotozoarios/síntesis química , Antiprotozoarios/química , Entamoeba histolytica/fisiología , Entamebiasis/tratamiento farmacológico , Entamebiasis/parasitología , Giardia lamblia/fisiología , Giardiasis/tratamiento farmacológico , Giardiasis/parasitología , Humanos , Extractos Vegetales/química , Compuestos de Azufre/síntesis química , Compuestos de Azufre/química
11.
Food Chem ; 283: 1-10, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30722847

RESUMEN

Bromelain is an important industrial proteolytic enzyme which has great commercial value and is of wide application in food, beverage, tenderization, cosmetic, textile and pharmaceutical industries. In this work, the core-shell-shell magnetic polymeric microspheres (Fe3O4@SiO2@P(NIPAM-co-AIM)/Ni2+) composed of an SiO2-coated Fe3O4 magnetite core and a Ni2+-immobilized cross-linked poly (N-isopropyl acrylamide-co-propylimidazole) (NIPAM-co-AIM) shell were synthesized via distillation-precipitation polymerization. The Ni2+ cations in the magnetic polymeric microspheres shell provided docking sites for histidine and the microspheres exhibited excellent performance in the separation of bromelain with a binding capacity as high as 198 mg/g, and the recovery of enzyme activity could achieve 80%. It was found that the microspheres showed excellent performance for separation and purification of bromelain from the crude extract of pineapple peel, moreover the enzyme structure remained unchanged before and after elution process.


Asunto(s)
Acrilamidas/química , Ananas/química , Bromelaínas/aislamiento & purificación , Imidazoles/química , Microesferas , Polímeros/química , Bromelaínas/metabolismo , Óxido Ferrosoférrico/química , Histidina/química , Histidina/metabolismo , Microscopía Electrónica de Transmisión , Níquel/química , Extractos Vegetales/química , Polimerizacion , Dióxido de Silicio/química , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría , Difracción de Rayos X
12.
Nanotechnology ; 30(11): 115701, 2019 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-30557867

RESUMEN

Although the special architecture of two-dimensional (2D) nanomaterials endows them with unique properties, their poor colloidal stability remains a main bottleneck to fully exploit their applications in the biomedical field. Herein, this study aims to develop a simple and effective approach to in situ incorporate 2D graphene oxide (GO) nanoplatelets into a thermosensitive matrix to acquire hybrid nanogels with good stability and photothermal effect. In order to improve its stability, GO firstly underwent silanization to its surface with double bonds, followed by intercalation with N-isopropylacrylamide (NIPAM) in the presence of a disulfide-containing crosslinker via an emulsion method. Radical polymerization was then initiated to accelerate direct GO exfoliation in PNIPAM nanogels by forming covalent bonds between them. The well-dispersed GO nanopletlets in the nanogels not only displayed an enhanced photothermal effect, but also improved the encapsulation efficiency of an anticancer drug. The hybrid nanogels accelerate drug release under conditions mimicking the acidic/reducible solid tumor and intracellular microenvironments, most importantly, it can be further enhanced via remote photothermal treatment. The multifunctional nanogels potentiate their synergistic anticancer bioactivity as an ideal nanoplatform for cancer treatment.


Asunto(s)
Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Grafito/química , Nanopartículas/química , Óxidos/química , Acrilamidas/química , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacología , Liberación de Fármacos , Células HeLa , Humanos , Nanopartículas/ultraestructura , Fenómenos Ópticos , Fototerapia , Polimerizacion , Silanos/química
13.
Int J Biol Macromol ; 113: 669-680, 2018 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-29499266

RESUMEN

The functionalization of polysaccharides with synthetic polymers has attracted great attention owing to its application in many industrial fields. The aim of this work was to study the impact of pectin functionalization with N,N-diethylacrylamide (DEAAm). Pectin was modified via microwave-induced graft copolymerization of DEAAm using ceric ammonium nitrate (CAN) and N,N,N',N'-tetramethylethylenediamine (TEMED). FTIR, 13C NMR, DSC/TGA, XRD, and SEM techniques were used to verify the structure of graft copolymers. Various reaction conditions such as microwave irradiation time, temperature, microwave power, monomer, initiator, and TEMED concentrations were investigated to get a maximum grafting yield of 192%. Lower critical solution temperatures (LCST) of graft copolymers were determined by UV spectroscopy. Graft copolymers were found to be thermo-sensitive, with LCST of 31°C and high thermal resistance. Biocompatibility test of copolymers showed that copolymers were not cytotoxic to L929 fibroblasts cells and can be used as a biomaterial.


Asunto(s)
Acrilamidas/química , Acrilamidas/síntesis química , Microondas , Pectinas/química , Polímeros/química , Polímeros/síntesis química , Temperatura , Cerio/química , Técnicas de Química Sintética , Etilenodiaminas/química , Polimerizacion
14.
Talanta ; 181: 278-285, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29426513

RESUMEN

A thermo/pH dual-stimuli-responsive drug delivery system (DDS) based on polymer coated mesoporous silica nanostructures (MSNs) is developed for facilitating chemotherapy and photothermal therapy. Thermo/pH-responsive polymer, poly((N-isopropylacrylamide, NIPAM)-co-methacrylic acid, MA), is grafted onto MSNs by in situ polymerization, followed by loading a chemotherapeutic drug (doxorubicin hydrochloride, DOX) and a near-infrared-absorbing phototherapeutic agent (indocyanine green, ICG) to construct the intelligent drug delivery system, shortly as DOX-ICG-MSN@p(NIPAM-co-MA). At NIR irradiation, the photothermal conversion capability of ICG raises the temperature of the DDS and opens the gatekeeper by shrinkage of the copolymer p(NIPAM-co-MA), which triggers controlled release of DOX at an elevated temperature. On the other hand, drug release is also realized at pH 5.3, a characteristic pH value in cancer cell microenvironment, at which it not only causes the shrinkage of the pH-sensitive polymeric moiety of methacrylic acid in MSN@p(NIPAM-co-MA) but also deteriorates electrostatic interaction of DOX molecules in the mesoporous channel by protonation of silanols. In addition, ICG further ensures photothermal therapy (PTT) and photodynamic therapy (PDT). The cytotoxicity assay of HeLa cells shows obvious synergistic effect by demonstrating that the combined use of DOX and ICG is more effective in killing HeLa cells than free DOX and ICG. The endocytosis of the drug is monitored by cell imaging.


Asunto(s)
Doxorrubicina/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Nanoestructuras/química , Fototerapia/métodos , Acrilamidas/química , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/química , Doxorrubicina/farmacocinética , Liberación de Fármacos , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Verde de Indocianina/administración & dosificación , Verde de Indocianina/química , Metacrilatos/química , Microscopía Confocal , Nanoestructuras/ultraestructura , Temperatura
15.
J Nat Med ; 72(1): 12-19, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29124496

RESUMEN

The aim of our study is to find functional compounds from natural resources. We focus on plants grown in tropical areas, especially Madagascar and Thailand, because they have unique flora and are expected to contain interesting compounds. We review the functional compounds of the seed kernels of Entada phaseoloides and E. rheedei and their biological activities such as anti-proliferation and melanogenesis inhibitory properties, etc.


Asunto(s)
Acrilamidas/química , Fabaceae/química
16.
Bioorg Med Chem Lett ; 28(3): 437-440, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29287958

RESUMEN

NAMPT expression is elevated in many cancers, making this protein a potential target for anticancer therapy. We have carried out both NMR based and TR-FRET based fragment screens against human NAMPT and identified six novel binders with a range of potencies. Co-crystal structures were obtained for two of the fragments bound to NAMPT while for the other four fragments force-field driven docking was employed to generate a bound pose. Based on structural insights arising from comparison of the bound fragment poses to that of bound FK866 we were able to synthetically elaborate one of the fragments into a potent NAMPT inhibitor.


Asunto(s)
Acrilamidas/farmacología , Citocinas/antagonistas & inhibidores , Descubrimiento de Drogas , Inhibidores Enzimáticos/farmacología , Nicotinamida Fosforribosiltransferasa/antagonistas & inhibidores , Piperidinas/farmacología , Acrilamidas/síntesis química , Acrilamidas/química , Citocinas/genética , Citocinas/metabolismo , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química , Transferencia Resonante de Energía de Fluorescencia , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Nicotinamida Fosforribosiltransferasa/genética , Nicotinamida Fosforribosiltransferasa/metabolismo , Piperidinas/síntesis química , Piperidinas/química , Relación Estructura-Actividad
17.
Int J Biol Macromol ; 103: 338-346, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28512054

RESUMEN

Psyllium seed polysaccharide was modified to investigate its use as multifunctional pharmaceutical excipient. The objective of this study was isolation of psyllium seed polysaccharide and crosslinking with acrylic acid using N,N-methylene bisacrylamide and its characterization. Acrylic acid was used as monomer and ammonium persulfate as initiator. A full factorial design was employed to optimize the crosslinking. The modified polysaccharide was characterized by FTIR, DSC, PXRD, loss on drying, pH, viscosity, micromeritics properties and swelling studies in 0.1N HCl, 0.5N NaOH, phosphate buffer pH 6.8. It was observed that swelling of crosslinked polysaccharide increased with decreased concentration of monomer and increasing concentration of crosslinker. Greater degree of grafting was observed with increase in crosslinker and monomer concentration. Dispersions of 1% w/v of PPS and APPS show pseudoplastic behavior. No clinical signs of toxicity were evident in repeat dose toxicity studies conducted in rats. Administration of up to 350mg/kg/day of APPS was well tolerated by the animals. Modification of psyllium via graft copolymerization and network formation with the crosslinker, improved the property profile and utility of psyllium polysaccharide. The modified polysaccharide can be used for designing controlled release drug delivery systems due to its swelling ability.


Asunto(s)
Acrilamidas/química , Psyllium/química , Semillas/química , Acrilamidas/toxicidad , Acrilatos/química , Animales , Técnicas de Química Sintética , Portadores de Fármacos/química , Portadores de Fármacos/toxicidad , Masculino , Ratas , Reología , Temperatura
18.
J Agric Food Chem ; 65(3): 565-574, 2017 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-28049294

RESUMEN

The superabsorbent hydrogels were synthesized by grafting acrylic acid and acrylamide onto pineapple peel carboxymethyl cellulose and effect of carclazyte introduction was compared. The structure and morphology of the superabsorbents were investigated by Fourier transform infrared spectroscopy, X-ray diffraction, and field emission scanning electron microscopy. Swelling behaviors of the superabsorbents were investigated in distilled water, 0.9% NaCl solution, various salt and pH solutions, as well as surfactant solutions and simulated physiological fluids. The swelling dynamic mechanism of the superabsorbents was explained well by Fickian diffusion and Schott's pseudo-second-order models. The introduction of carclazyte effectively improved the swelling capacity of the superabsorbents in various solutions as well as its salt- and pH-sensitivity. The prepared superabsorbents also exhibited excellent sensitivities to various surfactant solutions and simulated physiological fluids, showing potential applications in the biomaterials field.


Asunto(s)
Acrilamidas/química , Ananas/química , Carboximetilcelulosa de Sodio/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Extractos Vegetales/química , Adsorción , Catálisis , Frutas/química , Concentración de Iones de Hidrógeno , Difracción de Rayos X
19.
Nanomedicine ; 13(3): 1235-1243, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27913213

RESUMEN

Combination of polymer therapeutics and hyperthermia has been shown to enhance accumulation in selectively heated tumor tissue. The additional use of heat shock (HS)-targeting towards tumor tissues can further enhance accumulation and retention, and improve therapeutic outcomes. In this work, high intensity focused ultrasound (HIFU) was used to generate hyperthermia in prostate tumor tissue. Upregulation of the cell surface HS receptor glucose regulated protein 78 kDa (GRP78) was observed after treatment with HIFU hyperthermia which was then targeted by specific HS-targeting peptides. We used the peptide sequence WDLAWMFRLPVG attached to the side chains of water-soluble N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers containing docetaxel (DOC) conjugated via a lysosomally degradable linker. It was shown that HIFU-mediated HS-targeted copolymer-DOC conjugates improved treatment efficacy in a murine prostate tumor xenograft model. These results show that the use of HIFU hyperthermia in combination with HS-targeted polymer-drug conjugates has potential to improve therapeutic outcomes in prostate cancer treatment.


Asunto(s)
Antineoplásicos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Hipertermia Inducida/métodos , Neoplasias de la Próstata/terapia , Taxoides/administración & dosificación , Acrilamidas/química , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Docetaxel , Chaperón BiP del Retículo Endoplásmico , Humanos , Masculino , Ratones Desnudos , Péptidos/química , Próstata/efectos de los fármacos , Próstata/patología , Neoplasias de la Próstata/patología , Taxoides/uso terapéutico
20.
Ecotoxicol Environ Saf ; 134(Pt 2): 421-426, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26546239

RESUMEN

Biodegradable polymeric hydrogels are a unique class of macromolecular networks that can hold a large fraction of an aqueous solvent within their structures. They are particularly suitable for biomedical applications including controlled drug delivery, because of their ability to stimulate biological tissues. Many hydrogel-based networks have been designed and fabricated to meet the needs of pharmaceutical and medical fields. The investigation deals with the environment friendly synthesis of biodegradable semi interpenetrating hydrogel networks based on cross-linked poly(acrylamide) through an optimized rapid redox solution polymerization with N, N'Methylenebisacrylamide (MBA) in presence of Carboxymethylcellulose (CMC).The silver nanoparticles within hydrogel networks as nano reactors have been prepared by green synthesis via insitu reduction of silver nitrate (AgNO3) using Azadirachta Indica (Neem) plant extract under atmospheric conditions. The synthesized nanocomposites were characterised by FTIR spectroscopy, UV-Visible Spectroscopy, Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM) and Dynamic light scattering (DLS) technique. The thermal properties of the nanocomposite was analyzed by Thermogravimetric Analysis (TGA). The pH response and drug release profile of the synthesised biodegradable Silver-Hydrogel nanocomposite was investigated. Further, it was observed that physicochemical interaction between the polymeric nanocomposites and drug influences the degree of matrix swelling and therefore, its porosity and diffusion release process.


Asunto(s)
Acrilamidas/química , Resinas Acrílicas/química , Carboximetilcelulosa de Sodio/química , Sistemas de Liberación de Medicamentos , Hidrogeles/química , Nanocompuestos/química , Plata/química , Antibacterianos/química , Azadirachta , Plásticos Biodegradables/química , Liberación de Fármacos , Escherichia coli , Hidrogeles/síntesis química , Concentración de Iones de Hidrógeno , Extractos Vegetales , Porosidad , Nitrato de Plata/química , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
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