1. Unusual Fluorescence of Eu(III)Porphyrin Entrapped In Sol-gel Silica Matrix Unusual Fluorescence of Eu(III)Porphyrin Entrapped In Sol-gel Silica Matrix Stanisław Radzki a, Joanna Dargiewicz-Nowicka a, Magdalena Makarska a and Janina Legendziewicz b a Faculty of Chemistry, Maria Curie-Skłodowska University b Faculty of Chemistry Wrocław University

2. Porphyrin importance Porphyrins and their derivatives are widely applied in analytical chemistry. They can be used for analysis of cations, anions, organic compounds and gases. Methods are mostly based on porphyrin spectral and electrochemical properties. Energy transfer systems (solar energy, PDT). Possibility of the entrapment of organic reagents into sol-gel monolithic matrices and thin coatings. A new unique hybrid material (mixed organic and inorganic compounds) can be applied in chemo- and biosensors.

3. Analytical applications of porphyrins Spectrophotometic metal determination

4. Analytical applications of porphyrins Other compounds determinated using porphyrins

5. Aim of this work Method of the preparation of cationic porphyrin doped silica gels. Europium(III) porphyrin complex synthesis. Spectral characterisation of the cationic porphyrin and its Eu(III) complex in solutions and monolithic gel.

6. Porphyrin ring and its uv-vis spectrum

7. Sol-gel processing basics Sol coating Gelation percipitation spinning Ceramic fibers Solvent removing Evaporation Xerogell Glass, dense ceramics Aerogel Heating Dense film Heating Xerogel film Wet gel Unisized Gelled spheres Oven 1. HYDROLYSIS S i(OR) 4 + nH 2 O  (OR) 4-n -Si-(OH) n + nROH 2. CONDENSATION (RO) 3 Si-OR + HO-Si(OR) 3  (RO) 3 Si-O-Si(OR) 3 + ROH (RO) 3 Si-OH + HO-Si(OR) 3  (RO) 3 Si-O-Si(OR) 3 + H 2 O

8. Sol-gel method

9. Sol-gel method advantages Material homogenization High purity Mixing in the atomic scale of the various compounds (possibility of organic material addition) Good control over surface or powder size

10. TEOS (tetraethyl orthosilicate) Si(OC 2 H 5 ) 4 + nH 2 O  (OC 2 H 5 ) 4-n -Si-(OH) n + nC 2 H 5 OH (C 2 H 5 O) 3 Si-OC 2 H 5 + HO-Si(OC 2 H 5 ) 3  (C 2 H 5 O) 3 Si-O-Si(OC 2 H 5 ) 3 + C 2 H 5 OH (C 2 H 5 O) 3 Si-OH + HO-Si(OC 2 H 5 ) 3  (C 2 H 5 O) 3 Si-O-Si(OC 2 H 5 ) 3 + H 2 O

11. EuTMePyP(acac) synthesis Eu(acac) 3 + H 2 TMePyP  EuTMePyP(acac) + 2Hacac

12. EuTMePyP(acac) Europium(III)(meso-tetrakis(1-methyl-4- pirydyl)porphyrin) acetylacetonate)

13. EuTMePyP(acac) EuP(acac) + 4H +  H 4 P 2+ + Eu 3+ + acac - EuP(acac) + 3H 2 O  Eu(OH) 3 + Hacac + H 2 P

14. H 2 TMePyP and EuTMePyP(acac) uv-vis absorption spectra in various solvents

15. H 2 TMePyP – excitation and emission spectra

16. H 2 TMePyP and EuTMePyP(acac) uv-vis spectra in hydrogel

17. Excitation spectra of H 2 TMePyP, EuTMePyP(acac) and EuCl 3

18. Fluorescence spectra of H 2 TMePyP, EuTMePyP(acac) and EuCl 3

19. Conclusion Synthesis of the EuTMePyP(acac) complex not earlier described in the literature No fluorescence in solutions Strong fluorescence emission in hydrogel, probably due to the „axial ligand exchange” or silica-Eu(III)P reaction

20. Porphyrin monolayer formation on the silica gel surface D. Delmarre, R. Meallet, C. Bied-Charreton, R.B. Pansu: “Heavy metal ions detection in solution, in sol-gel and with grafted porphyrin monolayers”, J. Photochem. and Photobiol. A, 1999, 124, 23.