NVITATION TO NOMINATE A PR REU STUDENT TO PARTICIPATE IN THE RESEARCH EXPERIENCES FOR UNDERGRADUATES SYMPOSIUM (REUS), ARLINGTON,VA,

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1 INVITATION TO NOMINATE A PR REU STUDENT TO PARTICIPATE IN THE RESEARCH EXPERIENCES FOR UNDERGRADUATES SYMPOSIUM (REUS), ARLINGTON,VA, 2013, 2014, 2015 The Council on Undergraduate Research and the National Science Foundation invite you to nominate a REU student researcher from your Summer REU Site Program to participate in our Research Experiences for Undergraduates Symposium (REUS).

2 The nominee for REUS 2013 was Ivan D. Acevedo Ortiz Ivan D. Acevedo Ortiz, Research Mentor, Dr. Antonio E. Alegria, UPR-Humacao SONOCHEMICAL ACTIVATION OF QUINONE PRECURSORS Sonodynamic therapy is a promising new modality for cancer treatment based on the synergistic effect on cell killing by the combination of a drug (sonosensitizer) and ultrasound. It can penetrate deep within the tissue and can be focused on a small region of a tumor to chemically activate relatively nontoxic molecules into antitumor compounds. Ultrasound (US) is a type of mechanical sound wave with periodic vibrations in a continuous medium at frequencies greater than 20 khz over the range of human hearing (16-20 khz). Ultrasound has several applications in medical fields. One of those is the nonthermal low-intensity US irradiation as a potential candidate for cancer therapy. This work was focused on the US-induced conversion of the relatively non toxic compound, p- hydroxybenzoic acid (4-HBA) into antitumor compounds. This compound is the starting material for a group of compounds known as parabens, which are widely used as additives in cosmetics, drugs and food. Using HPLC it was found in this work that low frequency US-irradiation of 4-HBA produces hydroquinone and p-benzoquinone with quantities increasing with US exposure period. The identities of these sonoproducts were obtained by comparing their HPLC peaks retention time with authentic sample standards. These sonoproducts are known to have anticancer activity against several tumor cells. In addition, sonolysis of 4-HBA in the presence of glutathione (GSH) consumes glutathione in larger amounts as compared to sonolyses in the absence of this compound. Both GSH oxidations by p-benzoquinone and Michael addition of GSH to this quinone should account for this observation.

3 The nominees for REUS 2014 were Astrid M. Rodriguez and Natalia I. Roman Astrid M. Rodriguez (left), Research Mentor Dr. Mit kel Santiago Synthesis, characterization and photoelectrochemical behavior of ZnO nanorods Zinc oxide (ZnO) is a white inorganic compound that appears as crystalline powder and a semiconductor that have been used for different applications which include, but do not limit to, medicine, sensors, solar energy harvesting applications, among others. In our group we synthesize ZnO nanorods by simple and efficient method in aqueous media using zinc nitrate [Zn(NO3)2] and sodium hydroxide [NaOH]. Afterwards, we performed an acid-base reaction using benzoic acid in different molar concentration. In this project, we explore the synthesis and characterization of ZnO nanorods. The ZnO nanorods were characterized by different spectroscopic and analytical techniques such as X- Ray Powder Diffraction (XRPD), Scanning Electron Microscope (SEM), Energy Disperse Spectroscopy (EDS), UVvis and IR Spectroscopy. Preliminary results demonstrate that upon addition of benzoic acid to zinc oxide particles induces the formation of zinc oxide nanorods. These nanorods will be used for solar energy harvesting and for biosensing applications. Their performance in dye sensitizer solar cells was also performed and tested. This poster will present preliminary results of these materials

4 The Nominee for 2015 was Angel S. Breton Vega Angel. S. Breton Vega, Research Mentor, Dr. Samuel S. Hernandez, UPR-Mayaguez DETECTION OF EXPLOSIVE VAPORS WITH FLUORESCENT POLYMER-POROUS SILICON MICROCAVITY DEVICE Polymers entrapped in porous silicon (PSi) microcavities (MC) and porous silicon MC thin films have been studied as prospective means to design and build sensors for vapor phase explosives detection using photoluminescence (PL) and impedance spectroscopy (IS). Several of the polymers used were synthesized in the laboratory for this project. The polymers were coupled to Emitech s Mark III prototype,that measures PL and IS. The photoluminescence spectra were analyzed using chemometrics routines for pattern recognition by principal component analysis (PCA) showing a high affinity between the polymers entrapped on the porous silicon MC thin films and the nitroaromatic explosives. The electrical measurements suggest that porous size in thin film take place in the detection of the explosives and solvents vapors. The results demonstrate that the thin films tested exhibit a moderate quenching PL to nitroaromatic explosives.

5 Natalia I. Roman, right and Astrid M. Rodriguez, left at the REUS/CUR Symposium, Arlington, VA October 2014

6 Natalia I. Roman, left and Astrid M. Rodriguez, right with Dr. Tyrone D. Mitchell, Program Officer NSF CHE at the REUS Symposium, Arlington, VA October 2014

7 Astrid M. Rodríguez at REUS 2014

8 Natalia I. Roman, center and Astrid Rodriguez, extreme left with fellow participants at the REUS/CUR Symposium, Arlington, VA October 2014

9 Natalia I. Roman and Astrid M. Rodríguez at REUS 2014

10 Natalia I. Roman and Astrid M. Rodríguez at REUS 2014

11 Angel S. Breton Vega at REUS 2014, Arlington, VA