電気化学測定法は，分子の酸化還元反応の際に流れる電流や電極界面の電位を測定することで，対象物質を検出する手法である．簡便・安価な検出手法として期待される一方，測定できる電位範囲が狭く微量物質の検出も困難であることから，測定対象となる物質が限られる点が課題とされてきた．著者らはこれまでに，広い電位範囲や低いノイズ電流といった特性を有するスパッタナノカーボン薄膜電極の開発に取り組んできた．本薄膜の表面物性（親疎水性や表面粗さ）を制御することで，従来電極では検出できなかった全核酸塩基，グリア伝達物質，脂溶性抗酸化物質，あるいは酵素の直接電子移動などをきわめて高感度かつ再現性良く測定できることを見いだした．これらはナノカーボン薄膜材料の精緻な設計によって，電気化学分析の適用範囲が拡大されたものであり，飲料・食品・環境・生体・医薬といった多くの分野における利用が期待される．

In organic semiconductor materials, investigating the energy levels is very important. For example, the combination of the donor’s and acceptor’s energy levels affects the performance of organic solar cells (OSCs). The HOMO and LUMO levels are generally determined by cyclic voltammetry or differential plus voltammetry, which require the solution state. However, these methods are influenced by the purity, solvent, solubility, vibration, and temperature. In this work, we employed photoemission yield spectroscopy and UV-vis-NIR spectroscopy in the thin-film state to measure the energy levels of magnesium porphyrin derivatives for OSCs. The results explained that the energy levels were correlated with a substituent introduced in the porphyrin core. In the case of electron-withdrawing substituent porphyrin, the HOMO and LUMO levels were lowest and the HOMO-LUMO gap was narrowest. On the other hand, electron-donating substituent porphyrin showed high-energy levels and a wide energy band gap. It is noteworthy that the energy levels were lower and the band gaps were narrower in the thin-film state compared with the solution state. This result explains that strong π-stacking derived from intermolecular interaction in thin films. We concluded that measurements of the energy levels in thin film state by PYS and UV-vis-NIR spectroscopy are beneficial for investigating organic semiconductor materials.

走査型電気化学顕微鏡は試料近傍の酸化還元種を検出し，マッピングする装置である．本総合論文では，電気化学計測に基づき受精卵や胚様体，細胞塊の機能評価を実施した研究について紹介する．球面拡散の原理に基づき球状の個々のサンプルが生成・消費する物質の流束を求めることで，酸素消費量（呼吸活性）や，アルカリホスファターゼ及びベータ-ガラクトシダーゼなどの酵素活性を評価した．走査型電気化学顕微鏡に基づく受精卵の呼吸測定は，タイムラプス顕微鏡や網羅的遺伝子発現解析など複数のパラメーターと組み合わせることにより，受精卵の発生過程のモニタリングや個々のサンプルの品質評価に応用できる．胚様体の呼吸活性やアルカリホスファターゼ活性と分化能の関係が評価されている．電気化学的にベータ-ガラクトシダーゼ活性を評価することにより，細胞塊の老化について定量することが可能となる．

電気化学発光は，電極反応で生成した発光材料の酸化体と還元体の間で電子移動が起こり，励起状態が形成され，その後，放射失活する際に観測される．材料の電気化学特性，光物性，均一系での電子移動反応など多くの要因が電気化学発光に関与している．電気化学発光の解析は，主に発光スペクトルと発光効率（強度）について行われるが，発光材料のフォトルミネッセンススペクトル等の光物性，電気化学特性，電子状態等を考慮することによって電気化学発光をより深く理解することができる．本総合論文では，いくつかの発光性分子の電気化学発光と光物性，電気化学特性を紹介するとともに，それらの電子状態が電気化学発光の各過程に及ぼす影響について述べる．

高炉スラグ中の二酸化ケイ素（SiO₂）と他の成分元素を誘導結合プラズマ発光分光分析で同時定量するために，蛍光X線分析に用いられているガラスビード作製法により第一段目の試料分解を行い，その後これを溶解して試料溶液を調製する方法を検討した．従来のアルカリ融解とは異なり自然剥離するガラスビードを酸溶解すればよいため操作性がよく，またフッ化水素酸を用いた酸分解のようにSiO₂の損失もないため，高炉スラグ中のSiO₂と他の成分元素の同時定量が可能である．また，ガラスビードを用いた蛍光X線分析におけるマトリックス補正のような，トレーサビリティーを損なうような数値計算も必要としない．高含有の酸化アルミニウム（Al₂O₃），SiO₂，酸化カルシウム（CaO）の分析値の確からしさは絶対分析である重量法や滴定法に劣ったものの，本法を用いることで迅速かつ簡便に，高炉スラグ中のナトリウム（Na），酸化マグネシウム（MgO），Al₂O₃，SiO₂，リン（P），カリウム（K），CaO，二酸化チタン（TiO₂），一酸化マンガン（MnO），鉄（Fe）を同時定量できた．

Prior to the coating of a sample to a filament surface, a Joule-heating treatment of the filament was performed to remove any impurities from the filament and to minimize the influence of the background in thermal ionization mass spectrometry. In this work, the effect of the surface condition of the tungsten filament induced by the Joule-heating treatment on an uranium isotopic (²³⁵U/²³⁸U) measurement has been investigated. By the Joule-heating treatment, crystal grains were formed on the filament surface, and the filament surface became smooth. It was found that by extending the Joule-heating time, the surface became smoother and the precision of uranium isotopic (²³⁵U/²³⁸U) measurement was improved.

Aluminium tridecamer (Al₁₃) has seemed to be stable in solutions because of its Keggin structure. Recently, some studies suggested that Al₁₃ would be decomposed under specific conditions, especially under the sulfate ion’s existence. However, the fact is that the reason that the sulfate ion leads Al₁₃ to be decomposed has not been clearly revealed yet. The main aim in this study was to evaluate the effect of the sulfate ion on Al₁₃ with Electrospray Ionization Mass Spectrometry (ESI-MS). The sulfate ion, which is an oxidant, was added to Al solutions before and after Al₁₃ formed. To discuss the results, the same experiments were carried out with ascorbic acid, which is a reductant, instead of the sulfate ion. As results of these experiments, it was deniable that a small amount of oxidation could deprive the Keggin structure of electrons, and thus caused the decomposition of Al₁₃. On the contrary, a much greater amount of ascorbic acid than that of sulfate ion would cause the decomposition of Al₁₃ by giving electrons into the Keggin structure. From these results, the Al Keggin structure maintains its itself even under the existence of a reductant.

Nanographenes have now become one of the most promising candidates for new functional materials because of their high fluorescence properties, electronic properties and opt-electric properties. Therefore, nanographenes have been mostly studied in the field of organic solar cells and organic light emitter diodes. Despite the importance of understanding their electronic character, their exact HOMO-LUMO energy levels were poorly understood. This is because of the difficulty in size and composition selective syntheses of nanographenes. In this study, we synthesized three nanographenes with different sizes of π conjugate systems and molecular distortion by using a bottom-up method. We conducted Photoemission yield spectroscopy in air to measure their HOMO levels directly. By combining those data with the HOMO-LUMO gap energy derived from the UV-Vis absorption spectra, we revealed energy diagrams of nanographenes. We found that the HOMO-LUMO gap energy becomes smaller by extending the π conjugate systems, and the energy levels of HOMO and LUMO become lower by introducing molecular distortion.