| Abstract
| - A one-dimensional assembly of gold nanoparticles chemically bonded to π-conjugated porphyrin polymers wasprepared on a chemically modified glass surface and on an undoped naturally oxidized silicon surface by the followingmethods: π-conjugated porphyrin polymers were prepared by oxidative coupling of 5,15-diethynyl-10,20-bis-((4-dendron)phenyl) porphyrin (6), and its homologues (larger than 40-mer) were collected by analytical gel permeationchromatography (GPC). The porphyrin polymers (>40-mer) were deposited using the Langmuir−Blodgett (LB)method on substrate surfaces, which were then soaked in a solution of gold nanoparticles (2.7 ± 0.8 nm) protectedwith t-dodecanethiol and 4-pyridineethanethiol. The topographical images of the surface observed by tapping modeatomic force microscopy (AFM) showed that the polymers could be dispersed on both substrates, with a height of2.8 ± 0.5 nm on the modified glass and 3.1 ± 0.5 nm on silicon. The height clearly increased after soaking in thegold nanoparticle solution, to 5.3 ± 0.5 nm on glass and 5.4 ± 0.7 nm on silicon. The differences in height (2.5 nmon glass and 2.3 nm on silicon) corresponded to the diameter of the gold nanoparticles bonded to the porphyrinpolymers. The distance between gold nanoparticles observed in scanning electron microscopic images was ca. 5 nm,indicating that they were bonded at every four or five porphyrin units.
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