We found that both the color intensity and the fluorescent intensity of the solution are linearly dependent on the metal concentration. This distinct color and fluorescent change FK228 in vivo due to the spirolactam ring opening makes this derivative valuable for sensing ions through fluorescent or naked-eye detection. Additionally, a new sensing strategy was evaluated by immobilizing the Rh-UTES derivative on porous silicon devices. We found that after immobilization procedure, the Rh-UTES derivate maintained its fluorescent properties. PSi/Rh-UTES’ sensing capabilities for Hg2+ detection
were studied. It was observed that metal-hybrid sensor coordination produces a 0.25-fold enhancement in the integrated fluorescent emission at 6.95 μM Hg2+ ion concentration. By comparing the fluorescence response of Rh-UTES derivative in liquid and solid phases, we found that the immobilization procedure produced a 277-fold integrated fluorescence increasing which highlights the benefits of using PSi optical devices as support of the organic receptor. This work may open the door to the development of optical fluorescence-based sensors that can be easily used in field without the need of complicated instrumentation, allowing the fast diagnosis of the quality of natural water sources or water from the industrial waste. Acknowledgements This work was supported SCH727965 research buy by the National
Council for Science and Technology of Mexico (CONACYT), Project No. CB-153161. We thank CONACYT for the following student scholarships: MDG No. 237466, LHA No. 270040, ABF No. 229949, and AA postdoctoral scholarship 2013 (3). We would like to thank the University of Guanajuato for NMR support via the CONACYT-UGTO National Vildagliptin Laboratory (Grant 123732).
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