A novel drug carrier based on SiO_2-coated silver nanoparticle aggregates and antitumor drug is successfully synthesized.The surface-enhanced Raman scattering（SERS） spectra of the antitumor drug in living cells are ...A novel drug carrier based on SiO_2-coated silver nanoparticle aggregates and antitumor drug is successfully synthesized.The surface-enhanced Raman scattering（SERS） spectra of the antitumor drug in living cells are obtained.By using silver nano-aggregates as SERS substrates instead of dispersed silver particles, a great improvement of SERS signal intensity is achieved.It is found that the chemical stability of the drug carrier can also be increased with the existence of SiO_2 shell.The adsorbing effect between antitumor drug 9-aminoacridine（9AA） and silver particles is investigated to optimize the SERS signal. The core/shell structure of the drug carrier is characterized by ultraviolet-visible（UV-Vis） spectroscopy and transmission electron microscopy（TEM） pictures.The experimental results show that the drug carrier offers biocompatibility,stability,and high SERS activity,holding the potential for realizing the intracellular drug tracing.展开更多
A novel structure with high surface enhanced Raman scattering （SERS） activity and bio-specificity as a SERS-based immuno-sensor （named as Raman reporter-labeled immuno-Au aggregate） is demonstrated and employed fo...A novel structure with high surface enhanced Raman scattering （SERS） activity and bio-specificity as a SERS-based immuno-sensor （named as Raman reporter-labeled immuno-Au aggregate） is demonstrated and employed for protein detection. In each fabrication process, the features of those aggregates are obtained and characterized by ultraviolet-visible （UV-Vis） extinction spectra, transmission electron microscopy （TEM） images, scanning electron microscopy （SEM） pictures, and SERS spectra. Experimental results indicate that proper amounts of the reporter molecules can result in the moderate aggregation morphologies of gold nanoparticles. Compared with the previously reported method using Raman reporterlabeled immuno-Au nanoparticles, more sensitive SERS-based protein detection is realized with this novel immuno-sensor.展开更多
Due to the excellent electro-optic properties of lead lanthanum zirconium titanate(ePb; LaTeZr; TiTO3, PLZT),compact 1 × 2 and 1 × 4 PLZT optical switches with a high response speed are proposed and fabricat...Due to the excellent electro-optic properties of lead lanthanum zirconium titanate(ePb; LaTeZr; TiTO3, PLZT),compact 1 × 2 and 1 × 4 PLZT optical switches with a high response speed are proposed and fabricated successfully in this Letter. By introducing a thin isolating layer between the waveguides and the electrodes, the absorption loss of the fabricated 1 × 2 PLZT switch caused by the electrodes is reduced 8.9 d B with a relatively low driving voltage. The 1 × 2 PLZT switch shows an insertion loss of 18.3 d B and crosstalk of-20.5 d B at an applied voltage of 9.5 V. The fabricated 1 × 4 switch array shows an insertion loss of 20.7 d B and a crosstalk of-20.5 d B at an applied voltage of 13 V. The response time of the switches is less than 27 ns, and the device’s size is only 15 mm × 6 mm. The switches can be used in optical communication systems.展开更多
Optical methods and MTT method are used to characterize the antiproliferation effect of antitumor drug 9-aminoacridine （9AA） with and without silver nanoparticles. Intracellular surface enhanced Raman scattering （S...Optical methods and MTT method are used to characterize the antiproliferation effect of antitumor drug 9-aminoacridine （9AA） with and without silver nanoparticles. Intracellular surface enhanced Raman scattering （SERS） spectra and fluorescent spectra of 9AA indicate the form of 9AA adsorbed on the surface of silver nanoparticles. Although both silver nanoparticles and antitumor drug can inhibit the growth of Hela cells, silver nanoparticles can slow down the antiproliferation effect on Hela cells at low concentration of antitumor drugs. Our experimental results suggest that silver nanoparticles may serve as slow-release drug carriers, which is important in antitumor drug delivery.展开更多
基金supported by the National Natural Science Foundation of China under Grant Nos.60708024supported by the National Natural Science Foundation of China under Grant Nos.60877024
文摘A novel drug carrier based on SiO_2-coated silver nanoparticle aggregates and antitumor drug is successfully synthesized.The surface-enhanced Raman scattering（SERS） spectra of the antitumor drug in living cells are obtained.By using silver nano-aggregates as SERS substrates instead of dispersed silver particles, a great improvement of SERS signal intensity is achieved.It is found that the chemical stability of the drug carrier can also be increased with the existence of SiO_2 shell.The adsorbing effect between antitumor drug 9-aminoacridine（9AA） and silver particles is investigated to optimize the SERS signal. The core/shell structure of the drug carrier is characterized by ultraviolet-visible（UV-Vis） spectroscopy and transmission electron microscopy（TEM） pictures.The experimental results show that the drug carrier offers biocompatibility,stability,and high SERS activity,holding the potential for realizing the intracellular drug tracing.
基金supported by the National Natural Science Foundation of China(Nos.60708024 and 60877024) the Specialized Research Fund for the Doctoral Program of Higher Education(No.20070286058)
文摘A novel structure with high surface enhanced Raman scattering （SERS） activity and bio-specificity as a SERS-based immuno-sensor （named as Raman reporter-labeled immuno-Au aggregate） is demonstrated and employed for protein detection. In each fabrication process, the features of those aggregates are obtained and characterized by ultraviolet-visible （UV-Vis） extinction spectra, transmission electron microscopy （TEM） images, scanning electron microscopy （SEM） pictures, and SERS spectra. Experimental results indicate that proper amounts of the reporter molecules can result in the moderate aggregation morphologies of gold nanoparticles. Compared with the previously reported method using Raman reporterlabeled immuno-Au nanoparticles, more sensitive SERS-based protein detection is realized with this novel immuno-sensor.
基金supported by the State Key Program of the National Natural Science Foundation of China under Grant No.61535012
文摘Due to the excellent electro-optic properties of lead lanthanum zirconium titanate(ePb; LaTeZr; TiTO3, PLZT),compact 1 × 2 and 1 × 4 PLZT optical switches with a high response speed are proposed and fabricated successfully in this Letter. By introducing a thin isolating layer between the waveguides and the electrodes, the absorption loss of the fabricated 1 × 2 PLZT switch caused by the electrodes is reduced 8.9 d B with a relatively low driving voltage. The 1 × 2 PLZT switch shows an insertion loss of 18.3 d B and crosstalk of-20.5 d B at an applied voltage of 9.5 V. The fabricated 1 × 4 switch array shows an insertion loss of 20.7 d B and a crosstalk of-20.5 d B at an applied voltage of 13 V. The response time of the switches is less than 27 ns, and the device’s size is only 15 mm × 6 mm. The switches can be used in optical communication systems.
基金supported by the National Natural Science Foundation of China (Nos.60708024 and 60877024)
文摘Optical methods and MTT method are used to characterize the antiproliferation effect of antitumor drug 9-aminoacridine （9AA） with and without silver nanoparticles. Intracellular surface enhanced Raman scattering （SERS） spectra and fluorescent spectra of 9AA indicate the form of 9AA adsorbed on the surface of silver nanoparticles. Although both silver nanoparticles and antitumor drug can inhibit the growth of Hela cells, silver nanoparticles can slow down the antiproliferation effect on Hela cells at low concentration of antitumor drugs. Our experimental results suggest that silver nanoparticles may serve as slow-release drug carriers, which is important in antitumor drug delivery.
