Nanogels-particles of polymer gels having the dimensions in the order of nanometers-are gaining attention for their wide application as biomaterials. Mainly, the nanogels are promising novel pharmaceutical carriers fo...Nanogels-particles of polymer gels having the dimensions in the order of nanometers-are gaining attention for their wide application as biomaterials. Mainly, the nanogels are promising novel pharmaceutical carriers for small biologically active agents, bin macromolecules and can be chemically modified to incorporate various ligands for targeted drug delivery. This important factor has stimulated research on dissimilar science field such as nanotechnology and biotechnology, polymer and materials sciences, biochemistry, radiation chemistry and pharmaceutical sciences. A multitude of techniques have been described for the synthesis of this nanomaterial from polymers. However, the use of ionizing radiation (γ, e-) has demonstrated to be especially suitable for obtaining polymeric nanogels with a high degree of purity for biomedical applications, although the gamma radiation has not been widely utilized for these purposes. The aim of this paper is to develop the synthesis of PVP (polyvynilpyrrolidone) nanogels by gamma irradiation, for their evaluation as potential pharmaceutical carriers. Experiments were performed using argon saturated solution of PVP (0.1-1%). Crosstinking reactions were carried out in a gamma irradiation chamber with a 60Co source (ISOGAMMA LLCo), at room temperature. The PVP concentration influence was evaluated in PVP solutions (0.1% and 0.25%) at 15 kGy. The SEM (scanning electron microscopy), ATR (attenuate total reflection spectroscopy), DLS (dynamic light scattering), and viscosimetry were used as characterization techniques.展开更多
In this study, a simple spraying method is used to prepare the transparent conductive films (TCFs) based on Ag nanowires (AgNWs). Polyvinylpyrrolidone (PVP) is introduced to modify the interface of substrate. Th...In this study, a simple spraying method is used to prepare the transparent conductive films (TCFs) based on Ag nanowires (AgNWs). Polyvinylpyrrolidone (PVP) is introduced to modify the interface of substrate. The transmittance and bending performance are improved by optimizing the number of spraying times and the solution concentration and controlling the annealing time. The spraying times of 20, the concentration of 2 mg/mL and the annealing time of 10 min are chosen to fabricate the PVP/AgNWs films. The transmittance of PVP/AgNWs films is 53.4%----67.9% at 380---780 nm, and the sheet resistance is 30 f~/n which is equivalent to that of commercial indium tin oxide (1TO). During cyclic bending tests to 500 cycles with bending radius of 5 ram, the changes of resistivity are negligible. The performance of PVP/AgNW transparent electrodes has little change after being exposed to the normal environment for 1 000 h. The adhesion to polymeric substrate and the ability to endure bending stress in AgNWs network films are both significantly improved by introducing PVP. Spraying method makes AgNWs form a stratified structure on large-area polymer substrates, and the vacuum annealing method is used to weld the AgNWs together at junctions and substrates, which can improve the electrical conductivity. The experimental results indicate that PVP/AgNW transpar- ent electrodes can be used as transparent conductive electrodes in flexible organic light emitting diodes (OLEDs).展开更多
A novel electrogenerated chemiluminescence (ECL) aptasensor for highly sensitive detection of thrombin was developed on the basis of poly(pyrrole-co-pyrrole propylic acid) nanoparticles loaded with aptamer and rut...A novel electrogenerated chemiluminescence (ECL) aptasensor for highly sensitive detection of thrombin was developed on the basis of poly(pyrrole-co-pyrrole propylic acid) nanoparticles loaded with aptamer and ruthenium complex. Thrombin binding aptamers served as the molecular recognition elements and ruthenium bis(2,2'-bipyridine) (2,2'-bipyridine-4,4'-dicarboxylic acid)-ethylenediamine (Rul) was used as an ECL signal complex. Novel electroactive polymers poly(pyrrole-co-pyr- role propylic acid) nanoparticles (Ppy-pa NPs) were synthesized by a simple alcohol-assisted microemulsion polymerization. Rul-Ppy-pa NPs were synthesized by covalently coupling Rul with the Ppy-pa NPs. Ppy-pa NPs and Rul-Ppy-pa NPs were characterized using a fourier transform infrared spectrometer, super-conducting fourier digital NMR spectrometer, and trans- mission electron microscope. One ECL chemical sensor fabricated by immobilizing the Rul-Ppy-pa NPs on PIGE was developed for the determination of TprA with a high sensitivity and stability. The ECL aptasensor was fabricated by covalenfly coupling the thrombin binding aptamer-I (TBA-I) onto the surface of the paraffin-impregnated graphite electrode, which had been covalently modified with a monolayer of 4-aminobenzene sulfonic acid via electrochemical oxidations, for capturing thrombin onto the electrode and then the TBA-II labeled with Rul-Ppy-pa NPs was bound with epitope of thrombin. The ECL aptasensot showed an extremely low detection limit of 3.0×10^-16 mol/L for thrombin and a good selectivity. This work demonstrated that using Ppy-pa NPs as a carrier of ruthenium complex and molecular recognition element was a promising approach for the fabrication of ECL biosensor with high sensitivity.展开更多
文摘Nanogels-particles of polymer gels having the dimensions in the order of nanometers-are gaining attention for their wide application as biomaterials. Mainly, the nanogels are promising novel pharmaceutical carriers for small biologically active agents, bin macromolecules and can be chemically modified to incorporate various ligands for targeted drug delivery. This important factor has stimulated research on dissimilar science field such as nanotechnology and biotechnology, polymer and materials sciences, biochemistry, radiation chemistry and pharmaceutical sciences. A multitude of techniques have been described for the synthesis of this nanomaterial from polymers. However, the use of ionizing radiation (γ, e-) has demonstrated to be especially suitable for obtaining polymeric nanogels with a high degree of purity for biomedical applications, although the gamma radiation has not been widely utilized for these purposes. The aim of this paper is to develop the synthesis of PVP (polyvynilpyrrolidone) nanogels by gamma irradiation, for their evaluation as potential pharmaceutical carriers. Experiments were performed using argon saturated solution of PVP (0.1-1%). Crosstinking reactions were carried out in a gamma irradiation chamber with a 60Co source (ISOGAMMA LLCo), at room temperature. The PVP concentration influence was evaluated in PVP solutions (0.1% and 0.25%) at 15 kGy. The SEM (scanning electron microscopy), ATR (attenuate total reflection spectroscopy), DLS (dynamic light scattering), and viscosimetry were used as characterization techniques.
基金supported by the National Natural Science Foundation of China(No.21174036)the National High Technology Research and Development Program of China(No.2012AA011901)the National Basic Research Program of China(No.2012CB723406)
文摘In this study, a simple spraying method is used to prepare the transparent conductive films (TCFs) based on Ag nanowires (AgNWs). Polyvinylpyrrolidone (PVP) is introduced to modify the interface of substrate. The transmittance and bending performance are improved by optimizing the number of spraying times and the solution concentration and controlling the annealing time. The spraying times of 20, the concentration of 2 mg/mL and the annealing time of 10 min are chosen to fabricate the PVP/AgNWs films. The transmittance of PVP/AgNWs films is 53.4%----67.9% at 380---780 nm, and the sheet resistance is 30 f~/n which is equivalent to that of commercial indium tin oxide (1TO). During cyclic bending tests to 500 cycles with bending radius of 5 ram, the changes of resistivity are negligible. The performance of PVP/AgNW transparent electrodes has little change after being exposed to the normal environment for 1 000 h. The adhesion to polymeric substrate and the ability to endure bending stress in AgNWs network films are both significantly improved by introducing PVP. Spraying method makes AgNWs form a stratified structure on large-area polymer substrates, and the vacuum annealing method is used to weld the AgNWs together at junctions and substrates, which can improve the electrical conductivity. The experimental results indicate that PVP/AgNW transpar- ent electrodes can be used as transparent conductive electrodes in flexible organic light emitting diodes (OLEDs).
基金supported by the National Natural Science Foundation of China (21027007, 20975065 & 20775046)
文摘A novel electrogenerated chemiluminescence (ECL) aptasensor for highly sensitive detection of thrombin was developed on the basis of poly(pyrrole-co-pyrrole propylic acid) nanoparticles loaded with aptamer and ruthenium complex. Thrombin binding aptamers served as the molecular recognition elements and ruthenium bis(2,2'-bipyridine) (2,2'-bipyridine-4,4'-dicarboxylic acid)-ethylenediamine (Rul) was used as an ECL signal complex. Novel electroactive polymers poly(pyrrole-co-pyr- role propylic acid) nanoparticles (Ppy-pa NPs) were synthesized by a simple alcohol-assisted microemulsion polymerization. Rul-Ppy-pa NPs were synthesized by covalently coupling Rul with the Ppy-pa NPs. Ppy-pa NPs and Rul-Ppy-pa NPs were characterized using a fourier transform infrared spectrometer, super-conducting fourier digital NMR spectrometer, and trans- mission electron microscope. One ECL chemical sensor fabricated by immobilizing the Rul-Ppy-pa NPs on PIGE was developed for the determination of TprA with a high sensitivity and stability. The ECL aptasensor was fabricated by covalenfly coupling the thrombin binding aptamer-I (TBA-I) onto the surface of the paraffin-impregnated graphite electrode, which had been covalently modified with a monolayer of 4-aminobenzene sulfonic acid via electrochemical oxidations, for capturing thrombin onto the electrode and then the TBA-II labeled with Rul-Ppy-pa NPs was bound with epitope of thrombin. The ECL aptasensot showed an extremely low detection limit of 3.0×10^-16 mol/L for thrombin and a good selectivity. This work demonstrated that using Ppy-pa NPs as a carrier of ruthenium complex and molecular recognition element was a promising approach for the fabrication of ECL biosensor with high sensitivity.