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dc.contributor.advisorMaharaj, Tomar
dc.contributor.authorPeña-Duarte, Armando M.
dc.description.abstractStrong luminescent CuInX2/ZnX (X=S,Se) core/shell quantum dots were synthesized by a novel nontoxic and inexpensive organometallic method in two simple steps of CuInS2 and CuInSe2 core formation and ZnS and ZnSe shell over coating at 240° C, respectively. X-ray diffraction pattern confirms the CuInX2 core and CuInX2/ZnX core/shell (X=S,Se). HR- TEM images revealed that the particle sizes is homogeneous and the CuInS2/ZnS and CuInSe2/ZnSe core/shell nanoparticles are pyramidal in shape by CuInS2 and CuInSe2 tetragonal phase with average diameters of approximately 4 nm to core and 6 nm to core shell structure. CuInS2/ZnS and CuInSe2/ZnSe core/shell quantum dots shown excellent photoluminescence properties with high fluorescence emission from 750 nm to 850 nm. Quantum confinement effects were observed for red and Near-IR emission and quantum yield increasing form 11% to 62% after ZnSe overcoating for ternary chalcopyrites of CuInSe2. The CuInSe2/ZnSe core/shell quantum dots synthetized were used as photosensitizers in the production of ROS such as 1O2, since selenium has long been viewed as having anticancer effects based on early numerous experiments from animal models. The kinetic study of the singlet oxygen quenching reaction with 1,3- diphenylbenzofuran, was conducted by the photoluminescence emission intensity decrease. Here we report CuInSe2/ZnSe core/shell quantum dots revealed characteristics of a sensitizer nanoparticle produce reactive oxygen species such as singlet oxygen (1O2), it shown for a promising application in the photodynamic therapy and optical device application as photosensitizer in ROS production, as well as biosensors.en_US
dc.description.abstractCuInX2/ZnX (X=S,Se) core/shell quantum dots (QDs) con alta luminiscencia fueron sintetizados mediante un nuevo método no tóxico y eficiente, el cual se basa en dos pasos de reacción: uno para estructuras del núcleo o “core”de CuInS2 y CuInSe2 y, el otro, para el cascarón o “shell” de ZnS y ZnSe a 240°C. Se evidenció mediante XRD la formación de las estructuras CuInX2 core y CuInX2/ZnX core/shell (X=S,Se). Imágenes de HR-TEM muestran homogeneidad en el tamaño de partícula de ambos sistemas y evidencian la estructura piramidal de las calcopiritas que conforman el núcleo CuInS2 y CuInSe2 de los sistemas respectivos. Ambos sistemas muestran excelentes propiedades de emisión de fotoluminiscencia entre los 750 nm y los 850 nm. Los efectos de confinamiento cuánticos fueron observados en las regiones de emisión en el rojo y el IR cercano. El rendimiento cuántico se incrementó del 11% al 62% después de realizar el recubrimiento con ZnSe. Los QDs CuInSe2/ZnSe core/shell sintetizados fueron utilizados como foto-sensibilizadores en la producción de ROS tales como 1O2. El estudio cinético de la reacción de bloqueo del oxígeno singlete con 1,3-diphenylbenzofuran, se comprobó por la disminución de la intensidad de emisión de fotoluminiscencia del DPBF. Los estudios cinéticos con CuInSe2/ZnSe core/shell QDs revelaron características de sensibilizador para producir especies reactivas del oxígeno tales como el oxígeno singlete (1O2). Estos resultados permiten plantear la aplicación de CuInSe2/ZnSe core/shell QDs en la terapia fotodinámica, como fotosensibilizador en la producción de ROS, en el desarrollo de dispositivos ópticos y biosensores.en_US
dc.description.sponsorshipIRG2 project: Engineered Non-Toxic Quantum Dots Systems for Cancer Therapy Applications“ NSF-CREST-UPRM. National Science Foundation (NSF), Center for Research Excellence in Science and Technology (CREST) at the University of Puerto Rico at Mayagüez (UPRM)en_US
dc.titleChalcogenide based (cuins2/zns, cuinse2/znse) core/shell quantum dots for photodynamic therapyen_US
dc.rights.licenseAll rights reserveden_US
dc.rights.holder(c) 2015 Armando M. Peña-Duarteen_US
dc.contributor.committeeCastellanos, Dorial
dc.contributor.committeeLysenko, Sergiy
dc.contributor.representativeColón, Omar
dc.contributor.collegeCollege of Arts and Science - Scienceen_US
dc.contributor.departmentDepartment of Physicsen_US
dc.description.graduationSemesterFall (1rst Semester)en_US

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