胜肽分子組成有相當多種變化性，可藉由相異單體分子以不同的次序排列，因此我們可以得到特定長度、特定鍵結強度、對離子有專一性等性質。由於尺度上的優勢，胜肽可以用來發展分子電子元件，且可利用其對離子與有機分子的吸附特性，用來作為微型生物感應檢測器。
本研究利用第一原理對胜肽進行結構優化及電性分析，研究針對四種胜肽cysteamine-Cys、cysteamine-Gly-Cys、Cys-Gly-Cys、cysteamine-Gly-Gly-Cys (Cys=cysteine, Gly=glycine)，四種胜肽兩端皆為巰基使其與金電極相接進行討論，討論內容包含拉伸胜肽至斷裂對於系統能量以及電性的影響，拉伸量與電導值之間的趨勢；胜肽上吸附環境賀爾蒙雙酚A後之結構及電導值的變化；胜肽與銅離子結合形成錯合物的電性分析；胜肽以不同的螯合位置與連接銅離子連接形成錯合物，其結構是否會穩定存在。研究首先會將各系統結構優化在進行分析討論，其中的電性分析主要是觀察各系統的Transmission spectra、Fermi energy附近的Density of States分布情形及Fermi energy位置之Local Density of States，藉由這些結果計算出電導值以及分析。
根據研究結果，胜肽之電導值會隨著伸長而上升直至斷裂，其系統總能也會隨之升高，胜肽吸附雙酚A後電導會是原本胜肽電導的26倍左右，而胜肽-銅離子錯合物其結構可能性相當多故其電導值變化範圍也非常大，本研究針對部分可能結構進行討論實際穩定存在的可能性。

Silicon-based electronics are hard to head towards the nanoscale, the construction of electronic devices with individual molecules becomes an attractive alternative and has aroused interests in the study of the electronic properties of single molecules. Peptides are chosen as the object in the study because of the unlimited choice of different se-quences that can be tuned to obtain optimal binding strength and specificity for a metal ion or organic molecule. Based on the biochemical properties of peptide, it can be used as miniature biosensor. Four peptides are studied in our work, cysteamine-Cys, cysteam-ine-Gly-Cys, Cys-Gly-Cys, and cysteamine-Gly-Gly-Cys (Cys=cysteine, Gly=glycine), which each have two thiol termini that can form reproducible contact to Au electrodes. We analyze peptide and its systems by using first-principles calculations based on the density functional theory and the nonequilibrium Green’s function approach. Our re-search includes that conductance changing by stretching peptide, the conductance of pep-tide attached by Bisphenol A or copper ion, possible structures of peptide-Cu2+ complex-es. According to the results, the conductance of the peptide and the total energy of the system rise up with the elongation until breaking. After peptide adsorbing Bisphenol A, the conductance becomes about 26 times of the original peptide conductance. The con-ductance ranges of peptide-Cu2+ complexes are very large because there are considerable numbers of possible complexes structures. This study discusses some possible structures whether they stably exist or not.

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