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The surface properties of films made of p-methoxyphenacyl derivative terpolymers, associated with photocleavage by UV irradiation, and their optical patterning are investigated. The deprotection reaction has been monitored by UV and FTIR spectroscopy, contact angle measurements, and X-ray photoelectron spectroscopy, revealing the photoremoval of the protecting p-methoxyphenacyl group in high yields under mild conditions. Parallel and serial patterning of the films has been performed by selective irradiation through optical masks and by laser irradiation via fiber tips of a scanning near-field optical microscope, respectively. By irradiation of photolabile protected functional groups, free carboxylic groups become exposed to the surface with which fluorescent dyes and proteins can be associated specifically.

A first generation dendrimer D1 was placed onto defined surfaces to study the excitation energy transfer between D1 as donor molecule and a pyrene containing polymer 213 as acceptor molecule in Langmuir−Blodgett (LB) multilayers. Fluorescence experiments were carried out at several excitation wavelengths (220, 260, 312, and 341 nm). D1 formed a closed LB layer with a collapse area of 73 Ų on an aqueous subphase, and a successful incorporation of D1 in LB multilayers onto quartz plates was possible. At 220 nm excitation wavelength the adjacent donor and acceptor layers showed a dramatically increased fluorescence activity of the pyrene group in 213, which is about 20 times higher than that of the acceptor layer 213 without the present donor layer D1. 213 quenches the fluorescence activity of D1 more than 90% although only 5% of the maleic acid groups in 213 are labeled with pyrene. The excitation energy transfer between D1 and 213 may be assumed as a Förster energy transfer which was examined versus distance with two, four, six, and eight interlayers of an amphiphilic copolymer 12 between D1 and 213.