TY - JOUR
T1 - π-expanded ketocoumarins as efficient, biocompatible initiators for two-photon-induced polymerization
AU - Nazir, Rashid
AU - Danilevicius, Paulius
AU - Ciuciu, Adina I.
AU - Chatzinikolaidou, Maria
AU - Gray, David
AU - Flamigni, Lucia
AU - Farsari, Maria
AU - Gryko, Daniel T.
N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.
PY - 2014/5/27
Y1 - 2014/5/27
N2 - A series of π-expanded coumarins comprising of 4-5 conjugated rings were designed and synthesized. The strategic placement of two dialkylamino groups containing long alkyl chains attached to the peripheral ends of bis-coumarins resulted in dyes with superb solubility. As α,β-unsaturated ketones, these compounds display properties of donor-acceptor-donor (D-A-D)-type chromophores. Photophysical studies of the new functional dyes revealed a combination of favorable properties: strong absorption of blue and green light, weak fluorescence, reasonable two-photon absorption (2PA) cross-section, and complete solubility in nonpolar solvents. The fluorescence lifetimes of coumarin-derived α,β-unsaturated ketones were measured for the first time. The placement of two amine groups at peripheral positions of the dyes produced two-photon absorption cross-section values at the level of 150-400 GM around 800 nm, which generated two-photon photoinitiation. The highest 2PA cross-section was approximately 400 GM for the derivative of 4-methylcyclohexanone. Directly using these compounds as sensitizer or initiator, two (2D)- and three-dimensional (3D) nanopatterns were successfully fabricated by two-photon initiated polymerization. 3,3′-Carbonyl- biscoumarin, which contains two dihexylamino substituents at positions 7 and 7′ possesses the largest fabrication window. MC3T3-E1 preosteoblastic cells exhibited strong adherence to all π-expanded coumarins and the same spindle-shaped morphology as the tissue culture treated polystyrene control surface. Additionally, our results showed an increase in cell proliferation after 3 and 7 days in culture, as well as a high cell viability of approximately 100% on all materials compared to the control surface. These findings confirm that D-A-D-type ketocoumarin derivatives used as potential photoinitiators are noncytotoxic and can be used in the fabrication of biomaterial scaffolds for tissue engineering applications.
AB - A series of π-expanded coumarins comprising of 4-5 conjugated rings were designed and synthesized. The strategic placement of two dialkylamino groups containing long alkyl chains attached to the peripheral ends of bis-coumarins resulted in dyes with superb solubility. As α,β-unsaturated ketones, these compounds display properties of donor-acceptor-donor (D-A-D)-type chromophores. Photophysical studies of the new functional dyes revealed a combination of favorable properties: strong absorption of blue and green light, weak fluorescence, reasonable two-photon absorption (2PA) cross-section, and complete solubility in nonpolar solvents. The fluorescence lifetimes of coumarin-derived α,β-unsaturated ketones were measured for the first time. The placement of two amine groups at peripheral positions of the dyes produced two-photon absorption cross-section values at the level of 150-400 GM around 800 nm, which generated two-photon photoinitiation. The highest 2PA cross-section was approximately 400 GM for the derivative of 4-methylcyclohexanone. Directly using these compounds as sensitizer or initiator, two (2D)- and three-dimensional (3D) nanopatterns were successfully fabricated by two-photon initiated polymerization. 3,3′-Carbonyl- biscoumarin, which contains two dihexylamino substituents at positions 7 and 7′ possesses the largest fabrication window. MC3T3-E1 preosteoblastic cells exhibited strong adherence to all π-expanded coumarins and the same spindle-shaped morphology as the tissue culture treated polystyrene control surface. Additionally, our results showed an increase in cell proliferation after 3 and 7 days in culture, as well as a high cell viability of approximately 100% on all materials compared to the control surface. These findings confirm that D-A-D-type ketocoumarin derivatives used as potential photoinitiators are noncytotoxic and can be used in the fabrication of biomaterial scaffolds for tissue engineering applications.
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U2 - 10.1021/cm500612w
DO - 10.1021/cm500612w
M3 - Article
AN - SCOPUS:84901448828
VL - 26
SP - 3175
EP - 3184
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 10
ER -