Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.10.1 (ERK)
 95,504 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the present study, we have aimed to produce nanoparticles (NPs) possessing the capability of carrying both of the hydrophobic and hydrophilic drugs and reveal significant release for both drug types. Poly(epsilon-caprolactone) (PCL) grafted poly(vinyl alcohol) (PVA) copolymer (PCL-g-PVA) has been prepared and shaped in nano-particulate form to be adequate for carrying the drugs. Stannous octoate (Sn(II)Oct(2)) was used to catalyze PVA and epsilon-caprolactone monomer to chemically bond. Moreover, this catalyst enhanced side chain polymerization reaction for the utilized epsilon-caprolactone monomer to form poly(epsilon-caprolactone) (PCL). The formed PCL was attached as branches with PVA backbone. (1)H NMR has confirmed formation of PCL and grafting of PVA by this new polymer. Moreover, the vibration modes in the functional groups of PCL-g-PVA have been detected by FT-IR. The thermal alteration in the grafted polymer was checked by TGA analysis. The successfully synthesized grafted copolymer was able to self-aggregate into NPs by direct dialysis method. The size, morphology and charges associated with the obtained NPs were analyzed by DLS, TEM and ELS, respectively. PCL-g-PVA NPs were investigated as drug carrier models for hydrophobic and hydrophilic anti cancer drugs; paclitaxel and doxorubicin. In vitro drug release experiments were conducted; the loaded NPs reveal continuous and sustained release form for both drugs, up to 20 and 15 days for paclitaxel and doxorubicin, respectively. However, in a case of using pure drugs only, both drugs completely released within 1-2 h. The overall obtained results strongly recommend the use these novel NPs in future drug delivery systems.
 ...
PMID:Novel self-assembled amphiphilic poly(epsilon-caprolactone)-grafted-poly(vinyl alcohol) nanoparticles: hydrophobic and hydrophilic drugs carrier nanoparticles. 1902 Sep 53

For dye-sensitized solar cell (DSSC), highly ordered nanoporous TiO2 materials with crystalline frameworks were successfully synthesized from different silica templates including SBA-15, KIT-6 and MSU-H. A photoelectrode in DSSC was fabricated by adsorbing cis-bis(isothiocyanato)bis(2,2'-bipyridyl-4,4'-dicarboxylato)-ruthenium(II)bis-tetrabutylammonium dye (N719) onto the prepared TiO2 nanoparticles. The samples were characterized by XRD, TEM, FE-SEM, AFM and Brunauer-Emmett-Teller (BET), and FT-IR analysis. An investigation of the influence of the bonding structure of N719 dye and nanoporous TiO2 on the photovoltaic performance of DSSC revealed that the bonding structure of N719 on TiO2 films is caused by the unidentate and bidentate linkage. Based on the overall conversion efficiency (eta), fill factor (FF), open-circuit voltage (V(oc)) and short-circuit current (/sc) from the I-V curves measured, it was observed that the photoelectric performance is strongly dependent on the dispersion properties of the nanoporous TiO2 replicas from mesoporous silica templates.
 ...
PMID:Photovoltaic performance of nanoporous TiO2 replicas synthesized from mesoporous materials for dye-sensitized solar cells. 1919 74

Functionalized poly-epsilon-caprolactone-block-polyethyleneglycol (PCL-PEG) amphiphilic copolymers were prepared to be constituents of nanocarriers used for the targeting of specific cells. Hence, we conceived a smooth and simple photografting methodology on these copolymers using a bifunctional molecular clip (O-succinimidyl-4-(p-azido-phenyl)butanoate). We prepared PCL-PEGs with pendent N-hydroxysuccinimide esters and studied the grafting with 3H-lysine, which radioactivity was counted by LSC. Several parameters were investigated, such as behavior of homopolymers, initial concentrations, irradiation, and incubation durations. Evidences of a "PEG directed photografting" are discussed and this selectivity could be improved by a selective solvent technique. The photografting on different PCL-PEGs revealed a dependency of the rates to the crystallinity of the copolymers. Several controls by SEC, DLS, and TEM of the treated copolymers were realized. Lastly, the coupling of alpha-D-mannopyranoside ligand was performed, reaching amounts of 5400 nmol/g of PCL-PEG. This derivatized PCL-PEG enters in the preparation of nanocarriers used for the targeting of antigen presenting cells.
 ...
PMID:Light induced functionalization of PCL-PEG block copolymers for the covalent immobilization of biomolecules. 1922 75

Multi-arm star amphiphilic block copolymers (SABCs) with approximately 32 arms were synthesized and characterized for drug delivery applications. A hyperbranched polyester, boltorn H40 (H40), was used as the macroinitiator for the ring-opening polymerization of epsilon-caprolactone (epsilon-CL). The resulting multi-arm H40-poly(epsilon-caprolactone) (H40-PCL-OH) was further reacted with carboxyl terminated methoxy poly(ethylene glycol) (MPEG-COOH) to form H40-PCL-b-MPEG copolymers. The resulting SABCs were characterized by (1)H NMR spectroscopy and gel permeation chromatography (GPC). The critical aggregation concentration (CAC) of H40-PCL-b-MPEG was 3.8 mg/L as determined by fluorescence spectrophotometry. Below the CAC, stable unimolecular micelles were formed with an average diameter of 18 nm as measured by TEM. Above the CAC, unimolecular micelles exhibited agglomeration with an average diameter of 98 nm. The hydrodynamic diameter of these agglomerates was found to be 122 nm, as measured by dynamic light scattering (DLS). The drug loading efficacy of the H40-PCL-b-MPEG micelles was 26 wt%. Drug release study showed an initial burst followed by a sustained release of the entrapped hydrophobic model drug, 5-fluorouracil, over a period of 9-140 h. These results indicate that the H40-PCL-b-MPEG micelles have great potential as hydrophobic drug delivery carriers.
 ...
PMID:Biodegradable and biocompatible multi-arm star amphiphilic block copolymer as a carrier for hydrophobic drug delivery. 1942 65

In the present paper, ordered mesoporous silica (KIT-6) as support, nanosized TiO2 into KIT-6 was synthesized by titanium tetraisopropoxide hydrolysis. Then silver was loaded by deposition-precipitation method. Ag-TiO2/KIT-6 composite nanosized photocatalyst was firstly synthesized and a series of correlated catalysts were synthesized by the same preparation method. Methyl orange is presently adopted as a representative organic pollutant to evaluate the photocatalytic performance of the as-synthesized catalysts. The order of photocatalytic activity of the as-synthesized samples was found as Ag-TiO2/KIT-6 > Ag/TiO2 > TiO2/KIT-6 > TiO2 > Ag/KIT-6. Detailed characterizations were conducted by techniques including XRD, N2 physical adsorption, XPS, UV-Vis DRS and TEM. It was found that the Ag-TiO2 /KIT-6 sample shows the highest photocatalytic activity, which should be attributed to the Ag-TiO2 heterojunction structure and higher BET surface area of the Ag-TiO2/KIT-6 sample. Ag-TiO2 heterojunction improves the separation of photogenerated electron-hole pairs, thus enhancing the photocatalytic activity; Ag-TiO2/KIT-6 sample possesses high BET surface area, which facilitates adsorption and transportation of dye molecules, also leading to higher photocatalytic activity.
 ...
PMID:[Studies on Ag-TiO2/KIT-6 composite nanosized photocatalyst]. 1983 31

The effects of the addition of three different organosiloxanes, 3-aminopropyltrimethoxysilane (APTMS), 3-aminopropyltriethoxysilane (APTES) and 3-mercaptopropyltrimethoxysilane (MPTMS), on the phase behavior and the pore size of the surfactant-extracted materials have been investigated using powder XRD, TEM, Nitrogen adsorption/desorption isotherms and elemental analysis. The organosiloxanes were added to a typical synthesis, which results in a KIT-6 type in the absence of organosiloxanes. Their addition resulted in mesophase transformation or not, depending on the nature of functional groups of organosiloxanes. Increasing the content of APTMS or APTES in the silica sources not only led to the transformation of mesostructures from cubic bicontinuous Ia-3d to mixed mesostructure then towards two-dimensional (2-D) hexagonal p6mm and eventually to disordered structure, but also caused an increase of the pore size. However, the d spacing and the pore size of the cubic bicontinuous Ia-3d mesoporous solids can be decreased by addition of MPTMS between 0 and 2.5 mol% in the silica sources without a distinct decrease in the long-range order of the material. These results are discussed in terms of differences in the ability of the organosiloxanes to interact with the surfactant P123. The potential applications of these mesoporous materials are supports for the immobilization of enzymes, heavy metal sorbents, base catalysts, etc.
 ...
PMID:Influence of organosiloxanes on the properties of mesoporous materials. 1990 93

In this study, we synthesized a biodegradable triblock copolymer poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) (PEG-PCL-PEG, PECE) by ring-opening copolymerization, and nanohydroxyapatite (n-HA) powder was prepared by a hydrothermal precipitation method. The obtained n-HA was incorporated into the PECE matrix to prepare injectable thermosensitive hydrogel nanocomposites. (1)H NMR, FT-IR, XRD, DSC, and TEM were used to investigate the properties of PECE copolymer and n-HA/PECE nanocomposites. The rheological measurements for n-HA/PECE nanocomposites revealed that the gelation temperature was approximately 36 degrees C. The sol-gel-sol transition behavior and phase transition diagrams were recorded through a test tube inverting method. The results showed that n-HA/PECE nanocomposites still had thermoresponsivity like that of PECE thermosensitive hydrogel. The morphology of the nanocomposites was observed by SEM; the results showed that the nanocomposites had a 3D network structure. In addition, the effects of n-HA contents on the properties of n-HA/PECE nanocomposites are also discussed in the paper. From the results, n-HA/PECE hydrogel is believed to be promising for injectable orthopedic tissue engineering due to its good thermosensitivity and injectability.
 ...
PMID:Injectable biodegradable thermosensitive hydrogel composite for orthopedic tissue engineering. 1. Preparation and characterization of nanohydroxyapatite/poly(ethylene glycol)-poly(epsilon-caprolactone)-poly(ethylene glycol) hydrogel nanocomposites. 1994 37

The macromonomer of 2-hydroxyethyl methyacrylate-caprolactone (HPCL) was synthesized by the ring-opening polymerization (ROP) of epsilon-caprolactone, which was initiated by 2-hydroxyethyl methyacrylate (HEMA). Then, the graft terpolymers of NIPAAm-co-AAc-co-HEMA-g-PCL (PHNA-CL) with varying mole ratios were subsequently synthesized by free radical polymerization of HEMA-PCL, N-isopropylacrylamide (NIPAAm) and acrylic acid (AAc). PHNA-CL was further self-assembled in different types of solvent. All the as-prepared copolymers were characterized by 1H NMR, FT-IR and GPC. Micellization behaviors of micelles were studied by TEM and DLS. The micelles exhibited a phase transition temperature which can be readily adjusted by changing pH value of the micellization system. Micelle loaded with doxorubicin (DOX) was used to evaluate the drug release behavior. The release of DOX from micelles could be controlled by changing pH value and temperature in buffer solutions. The micelles are potentially to be used as a new anticancer drug carrier for intracellular delivery.
 ...
PMID:The pH-induced thermosensitive poly (NIPAAm-co-AAc-co-HEMA)-g-PCL micelles used as a drug carrier. 2021 89

In this paper, a new kind of polymeric nanocomposite materials based on nano-hydroxyapatite (n-HA) and PCL-Pluronic-PCL (PCFC) copolymer were prepared by in situ combination method. Firstly, the PCFC copolymer was synthesized by ring-opening polymerization of epsilon-caprolactone initiated by Pluronic (PEG-PPG-PEG); Secondly, n-HA powder were combined with PCFC to form polymeric composites in the presence of hexamethylene diisocyanate (HDI). The obtained composites were characterized by 1H-NMR, FTIR, XRD, TEM, SEM, DTA/TGA, and tensile testing. The results revealed that n-HA could be dispersed into polymer matrix uniformly, and the n-HA/PCFC composite showed great mechanical properties when the content of n-HA was 10 wt%. The microstructure and thermal properties of the composites were discussed in the paper too. The experimental results suggested that this polymeric nanocomposite might have great potential application in the field of tissue engineering.
 ...
PMID:Preparation and characterization of n-hydroxyapatite/PCL-pluronic-PCL nanocomposites for tissue engineering. 2035 8

Heparin is a potent anticoagulant agent that interacts strongly with antithrombin III to prevent the formation of fibrin clots. In the present work, poly(dimethylsiloxane)(PDMS)/graphite oxide-benzalkonium chloride-heparin (PDMS/modified graphite oxide) nanocomposite films were obtained by the solution intercalation technique as a possible drug delivery system. The heparin-benzalkonium chloride (BAC-HEP) was intercalated into graphite oxide (GO) layers to form GO-BAC-HEP (modified graphite oxide). Nanocomposite films were characterized by XRD, SEM, TEM, ATR-FTIR and TGA. The modified graphite oxide was observed to be homogeneously dispersed throughout the PDMS matrix. The effect of modified graphite oxide on the mechanical properties of the nanocomposite film was investigated. When the modified graphite oxide content was lower than 0.2 wt%, the nanocomposites showed excellent mechanical properties. Furthermore, nanocomposite films become delivery systems that release heparin slowly to make the nanocomposite films blood compatible. The in vitro studies included hemocompatibility testing for effects on platelet adhesion, platelet activation, plasma recalcification profiles, and hemolysis. Results from these studies showed that the anticoagulation properties of PDMS/GO-BCA-HEP nanocomposite films were greatly superior to those for no treated PDMS. Cell culture assay indicated that PDMS/GO-BCA-HEP nanocomposite films showed enhanced cell adhesion.
 ...
PMID:Biopolymer-modified graphite oxide nanocomposite films based on benzalkonium chloride-heparin intercalated in graphite oxide. 2037 48


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>