胜肽的種類很多，不同單分子胜肽有不一樣的結構與特性，但也因為分子細小與難以量測，各類相似的胜肽常常很難簡易地區分，因此我們利用第一原理計算分析不同胜肽通過金電極間隙時的電導，並比較其與量測到的電導的差異。
我們計算了12種胜肽的電導，包括tryptophan(W)、tyrosine(Y)、Phenylaniline(F)、Histidine(H)、phosphopyrosine(py)、proline(P)、lysine(K)、cysteine(C)、Methionine(M)、glutamic acid(E)、aspartic acid(D)、isoleuine(I) 等分子。利用兩側的金電極，中間包含胜肽，算出Transmission spectra與conductance，以了解各類胜肽在金電極連接下電導的差異，進而能幫助胜肽的檢測。
我們改變胜肽分子在y軸的位置，從-2Å至2Å，分五點，再加上轉動胜肽分子，分三種角度，來模擬單分子胜肽在金電極移動的情形，並將每個移動胜肽的數據作統計上分析，來觀察不同胜肽在transmission上的差異。我們觀察在不同的金極距離下，不同胜肽電導是否會發生改變，以及在Au[1 1 1]與Au[0 0 1]等電極方向下的影響。我們也探索將交換能從LDA轉換成GGA時，對12種胜肽電導的效應。我們希望了解何種結構的胜肽有較高的電導，以幫助實驗上的量測與分析，藉此提高生物檢測器的應用。
我們發現proline(P)與Histidine(H)，有較高的電導值。proline(P)高於其他胜肽，而Histidine(H)在金電極0.7nm至1.15nm時，其電導有逐漸高於其他胜肽的跡象。我們也觀察到，在金電極拉開長度越長時，包括lysine(K) Methionine(M)和Aspartic acid(D)，其電導都有些微的上升，我們判斷可能是因為其沒有酚官能基，或是其他複雜分子構成，為長鏈型的分子。

We calculated the conductance of 12 peptides, including tryptophan (W), tyrosine (Y), Phenylaniline (F), Histidine (H), phosphopyrosine (py), proline (P), lysine (K), cysteine (C). , Methionine (M), glutamic acid (E), aspartic acid (D), isoleine (I) and other molecules. Using the gold electrodes on both sides, the middle contains the peptide, and the transmission spectra and conductance are calculated to understand the difference in the conductance of the various peptides under the gold electrode connection.
We changed the position of the peptide molecule on the y-axis, from -2Å to 2Å, divided into five points, plus the rotation of the peptide molecule, in three angles, to simulate the movement of the single-molecule peptide on the gold electrode. The data of the mobile peptide was statistically analyzed to observe the difference in transmission of different peptides. We observed whether the conductance of different peptides will change under different gold pole distances, and the influence of electrodes such as Au[1 1 1] and Au[0 0 1]. We also explored the effects of 12 peptides on the conductance of exchanges from LDA to GGA.
We found that proline (P) and Histidine (H) have higher conductance values. Proline (P) is higher than other peptides, and Histidine (H) has a higher conductivity than other peptides at 0.7nm to 1.15nm. We also observed that the conductance is increased including the lysine(K) Methionine(M) and Aspartic acid(D).

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