Chlorophyll pigments are responsible for primary photosynthetic events in both green plant and algae. Their outstanding performance in the light capture, transfer and charge separation actions make these pigments attractive construction units for various artificial photophysical devices. Group has interest to develop new regioselective chlorin ring modifications in order to modify pigments: a) non-covalent bonding properties, b) electronic properties (oxidation potential, absorption and fluorescence) and c) to them to electronic acceptor in covalent or non-covalent fashion.

Photophysical studies have been conducted in collaboration with prof. N. Tkachenko, TUNI and prof. D. Guldi, Erlangen research groups.

At present we are in between the projects looking for funding. As most abundant biological pigment as well as light energy antenna and excitation to charge converter, chlorophylls deserve applications that exploits its full potential…

Related publications

T. Nikkonen, M. M. Oliva, A. Kahnt, M. Muuronen, J. Helaja, D. M. Guldi: Photoinduced charge transfer in self-assembling conformational switching chlorin dimer- azafulleroid in polar and non-polar media Chem Eur J. 2014, DOI: 10.1002/chem.201404786

K. Stranius, V. Iashin, T. Nikkonen, M. Muuronen, J. Helaja, N. Tkachenko: Effect of Mutual Position of Electron Donor and Acceptor on Photoinduced Electron Transfer in Supramolecular Chlorophyll-Fullerene Dyads J. Phys. Chem. A, 2014, 118, 1420-1429.

V. Iashin, T. V. Koso, K. Stranius, M. Muuronen, S. Heikkinen, J. Kavakka, N. V. Tkachenko, J. Helaja: Chlorophyll tailored 20-trifluoroacetamide and its azacrown derivative as pH sensitive colorimetric sensor probe with response to AcO2, F2 and CN2 ions3 RSC Adv. 2013, 3, 11485-11488.

V. Pale,T. Nikkonen, J. Vapaavuori, M. Kostiainen, J.Kavakka, J. Selin, I. Tittonen, J. Helaja: “Biomimetic zinc chlorin–poly(4-vinylpyridine) assemblies: doping level dependent emission–absorption regimes” J. Mater. Chem. C, 2013, 1, 2166-2173.

R. Haavikko, J. S. Kavakka, J. Helaja: beta-Keto ester aminolysis of pheophorbide a methyl ester: a facile route for asymmetric chlorin ring substitution, Tetrahedron Lett. 2010, 51, 714-716.

J. S. Kavakka, S. Heikkinen, I. Kilpeläinen, N. V. Tkachenko J. Helaja: Zn pyro-pheophorbide a – fulleronicotine dyad; Supramolecular self assembled donor – acceptor system for photoinduced charge separation, Chem. Comm. 2009, 758–760.

T. Nikkonen, R. Haavikko, J. Helaja: Hydrogen bond driven self-assembled C₂-symmetric chlorin syn dimers; unorthodox models for chlorophyll ‘special pairs’ in photosynthetic reaction centres Org. Biomol. Chem. 2009, 7, 2046–2052.