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The characteristics of Noria analogs with 12 ethoxy groups and 12 hydroxy groups (Noria-OEt), which were synthesized by the condensation reaction of 3-ethoxyphenol with 1,5-pentanedial, were examined in detail. The solubility of the synthesized Noria-OEt in common organic solvents was better than that of Noria. In addition, Noria-OEt was soluble in 2.38 wt% tetrametyl ammonium hydroxide (TMAH) aqueous as a developer. The thermal stability and mechanical properties were similar to those of Noria because of the ladder structure and amorphous characteristics, which means that the film-forming properties were confirmed. These characteristics are advantageous for use as a molecular glass photoresist. The patterning properties of the negative-type, alkaline developable, multicomponent photoresist based on Noria-OEt, with polyfunctional benzyl alcohols as a crosslinker and a photoacid generator, were evaluated with an extreme ultraviolet lithography system. This negative-type photoresist with 2,4-dihydroxymethyl-6-methylphenol as a crosslinker gave a resolution pattern of 35 nm half-pitch with 10.0 mJ cm À2 .

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To this end, several analytical methods have been developed for the quantitative determination of DA in shellfish. [5][6][7][8][9][10][11][12][13] At present, high-performance liquid chromatography (HPLC) with good accuracy and reproducibility is most widely employed for monitoring DA. Several HPLC methods have been developed using ultraviolet (UV), 5-11 mass spectrometry (MS) 10-12 and fluorececnce 13 detection. However, UV detection of underivatized DA lacks specificity because interferents can exhibit UV spectra similar to that of DA. Also, UV and fluorececnce detection of precolumn derivatized DA have multistep manipulation and are subject to interference from salts, buffers and proteinaceous materials. The MS detection method is sensitive and can give the most reliable results, but it requires a highly sophisticated apparatus and higher operating cost. Since these reported methods require a time-consuming cleanup of the sample prior to analysis, they are unsuitable for rapidly screening a large number of samples. If more sensitive and selective detection methods are developed, it is clear that a more rapid analytical system can be established.Chemiluminescence offers an attractive means for the detection of trace analysis due to its low detection limit, high selectivity and wide dynamic range, with relatively simple instrumentation.In recent years, tris(2,2′-bipyridine)-ruthenium(III), Ru(bpy)3 3+ , as a chemiluminescent (CL) reagent, has been shown to be a sensitive and selective detection method for the analysis of a wide range of compounds, 14 such as oxalate, 15 alkylamines, 16 amino acids [17][18][19] and active methylene compounds.20 Among amino acids, proline is a more reactive secondary amine, and can be detected in the pmol range. 17,21 DA contains a secondary amine moiety similar to that of proline, as shown in Fig. 1. Therefore, HPLC with CL detection using Ru(bpy)3 3+ can be expected to be applicable for determining DA. We have found that Ru(bpy)3 3+ reacts with DA and emits chemiluminescence. Based on this finding, we propose a new sensitive detection method of DA depending on the chemiluminescence of Ru(bpy)3 3+ . Co., Aso, Japan A new sensitive determination method of domoic acid based on the chemiluminescent reaction of tris(2,2′-bipyridine)ruthenium(III) has been developed. The method exhibited good reproducibility. The relative standard deviation of six replicate measurements was 1.6% for 10 ng ml -1. A calibration graph, based on a standard domoic acid solution, was linear over the range of 1 -500 ng ml -1 (coefficient of correlation, r 2 = 0.9995) and the detection limit was 8 pg (signal-to-noise ratio = 3) without any preconcentration and derivatization steps. This new method was successfully applied to a real sample of blue mussels spiked with 2 µg g -1 domoic acid.