RESUMEN
Ultraviolet (UV) photon detection is becoming increasingly important in the quest to understand the fundamental building blocks of our universe. Basic properties of neutrinos and Dark Matter are currently being explored through interactions with noble elements. In response to interactions with fundamental particles, these elements emit scintillation photons in the UV range. However, most available detectors have poor response in the UV so it is typically necessary to shift UV to a wavelength, matching the sensitivity of the viable detectors. We report on development of UV-enhanced photosensors using wavelength-shifting properties of nanoparticles. Several nanoparticle coatings were tested for absorption of UV light with subsequent emission in the visible wavelength for high energy particle detection. ZnS:Mn,Eu, ZnS:Mn, CuCy (Copper Cysteamine) and CdTe nanoparticles all exhibited enhanced detection for wavelengths in the range 200-320 nm in several different tests, while ZnS:Ag and CdS nanoparticle showed little or no enhancement in that range. In addition, various LaF3:Ce nanoparticle concentrations in approximately constant thickness of 2,5-diphenyloxazole (PPO)/polystyrene bases were also tested to optimize the nanoparticle concentration for the best outcome. Our studies indicated that ZnS:Mn,Eu, ZnS:Mn, Cu-Cy, CdTe and LaF3:Ce nanoparticles show potential for light detection from fundamental particle interactions.
RESUMEN
Copper Cysteamine (Cu-Cy) is a new photosensitizer and a novel radiosensitizer that can be activated by light, X-ray and microwave to produce singlet oxygen for cancer treatment. However, the killing mechanism of Cu-Cy nanoparticles on cancer cells is not clear yet and Cu-Cy nanoparticles as novel radiosensitizers have never been tested on colorectal cancers. Here, for the first time, we investigate the treatment efficiency of Cu-Cy nanoparticles on SW620 colorectal cells and elucidate the underlying mechanisms of the effects. The results show that X-ray activated Cu-Cy nanoparticles may kill SW620 cancerscells is in a dose-dependent manner. The JC-1 staining shows the mitochondrial membrane potential is decreased after the treatment. The observations confirm that Cu-Cy nanoparticles may improve X-ray radiotherapy on cancer treatment and X-ray activated Cu-Cy nanoparticles can be efficiently destroy colorectal cancer cells by inducing apoptosis as well as autophagy. As a new type of radiosensitizers and photosensitizers, Cu-Cy nanoparticles have a good potential for colorectal cancer treatment and the discovery of autophagy induced by X-ray irradiated Cu-Cy nanoparticles sheds a good insight to the mechanism of Cu-Cy for cancer treatment as a new radiosensitizers.
Asunto(s)
Cobre , Cisteamina , Nanopartículas del Metal , Fármacos Sensibilizantes a Radiaciones/farmacología , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Cobre/química , Cisteamina/química , Relación Dosis-Respuesta a Droga , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Nanopartículas del Metal/química , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Fármacos Sensibilizantes a Radiaciones/química , Rayos X , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismoRESUMEN
The applications of afterglow particles for photodynamic activation and biological imaging have become a topical research area. For these applications, it is critical to have water soluble nanoparticles. However, the synthesis of water soluble afterglow nanoparticles like Sr2MgSi2O7:Eu2+, Dy3+ is a challenging issue because most afterglow materials are very complicated in composition that cannot be synthesized by simple chemical routes. Here, for the first time, Sr2MgSi2O7:Eu2+, Dy3+ water soluble and stable nanoparticles are synthesize using a modified Sol-Gel method followed by the grinding and coating with APTES. The surface coating of the afterglow with APTES and the conjugation with PpIX and folic acid not only improve their water solubility but also enhance the PpIX luminescence by 10 times. More importantly, these strategies make it possible to produce singlet oxygen under X-ray irradiation, which is a very important result for deep cancer treatment. In addition, the surface coating and conjugation largely increase the cell uptake and greatly reduce their dark cytotoxicity. All these results indicate the methods reported here for afterglow nanoparticle synthesis, coating and conjugation are successful, and consequently, the prepared Sr2MgSi2O7:Eu2+, Dy3+/PPIX/Folic acid nano-conjugates are promising for X-ray induced photodynamic therapy on cancer treatment.
Asunto(s)
Nanopartículas del Metal/química , Nanocápsulas/química , Fotoquimioterapia/métodos , Propilaminas/química , Neoplasias de la Próstata/tratamiento farmacológico , Protoporfirinas/administración & dosificación , Silanos/química , Adsorción , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Composición de Medicamentos , Humanos , Masculino , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/ultraestructura , Nanocápsulas/administración & dosificación , Nanoconjugados/administración & dosificación , Nanoconjugados/química , Nanoconjugados/ultraestructura , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/síntesis química , Neoplasias de la Próstata/patología , Protoporfirinas/química , SolubilidadRESUMEN
We developed new optic devices - singly-doped luminescence glasses and nanoparticle-coated lenses that convert UV light to visible light - for improvement of visual system functions. Tb(3+) or Eu(3+) singly-doped borate glasses or CdS-quantum dot (CdS-QD) coated lenses efficiently convert UV light to 542 nm or 613 nm wavelength narrow-band green or red light, or wide-spectrum white light, and thereby provide extra visible light to the eye. In zebrafish (wild-type larvae and adult control animals, retinal degeneration mutants, and light-induced photoreceptor cell degeneration models), the use of Tb(3+) or Eu(3+) doped luminescence glass or CdS-QD coated glass lenses provide additional visible light to the rod and cone photoreceptor cells, and thereby improve the visual system functions. The data provide proof-of-concept for the future development of optic devices for improvement of visual system functions in patients who suffer from photoreceptor cell degeneration or related retinal diseases.
Asunto(s)
Luz , Nanopartículas/efectos de la radiación , Dispositivos Ópticos , Células Fotorreceptoras/fisiología , Células Fotorreceptoras/efectos de la radiación , Rayos Ultravioleta , Animales , Modelos Animales de Enfermedad , Degeneración Retiniana , Pez CebraRESUMEN
For the first time, transparent La0.2Y1.8O3 nanostructured polycrystalline scintillators were fabricated by sintering nanoparticle powders at high temperatures and their scintillation properties are reported. La0.2Y1.8O3 is a host material that has never been investigated as scintillators for radiation detection. Our observations found that La0.2Y1.8O3 has an intense scintillation luminescence, a detection efficiency higher than that of YAG:Ce and a comparable energy resolution to NaI and CsI scintillators. In addition, La0.2Y1.8O3 is stable and has luminescence decay lifetime in the picosecond range which is favorable for radiation detection. The luminescence of La0.2Y1.8O3 has a large Stokes-shift and a large emission bandwidth, and the luminescence is highly temperature dependent. Different from most doped scintillators, the luminescence of La0.2Y1.8O3 is most likely from the self-trapped excitons. The discovery of La0.2Y1.8O3 scintillators opens a new door for the research of new materials for radiation detection.