溴化四辛基銨(Tetraoctylammonium bromide (TOAB))所修飾的金電極被用來探討細胞色素C (cyt c )的電化學反應。Cyt c會經由擴散方式進入TOAB中。且其氧化還原電位從原本的0.025 V (vs. SCE) 變成 -0.1V (vs. SCE), 此結果顯示出TOAB在金電極表面所形成的疏水層對於cyt c具有很強的作用力，可造成cyt c的denature現象。進一步由Spectroelectrochemistry的實驗中發現在TOAB的環境中，還原後的cyt c在UV-Vis光譜中有兩根吸收峰，分別在560 and 610 nm的位置。因此可推斷此時的活化中心應變成接上氧氣的低自旋六配位鐵口卜口林錯合物。
Cyt c可對HAuCl4進行還原作用而產生不同形狀的金奈米粒子。 在穿透式電子顯微鏡(TEM)的觀察下，50 mM的氯離子會使得金奈米粒子顯現出不規則的扭曲狀。溴離子的加入會誘導金奈米形成三角形、五邊形、六角形以及棒狀的結構。溴離子會抑制金奈米的形成。在pH 3時，含有氯離子的cyt c-HAuCl4溶液中亦可形成不同形狀的金奈米粒子，且藉由TEM的解析顯示出polypeptide環繞在金奈米周圍，此係分子的作用力使得金奈米有聚集作用產生。
在以cyt c為還原劑的條件下，金奈米粒子的形狀及大小可藉由還原電位、溫度以及pH值的調控而獲得。

Cytochrome c is an electron transport protein in biological system. The redox potential of this protein was measured by suing tetraoctylammonium bromide modified gold electrode. In the system, cyt c must diffuse through the TOAB layer to reach the Au surface, and the strong hydrophobic tails of TOAB may trigger cyt c denature. The measured redox potential of -0.1 V is similar to oxygen-bound iron proteins. Spectroelectrochemistry of cyt c was performed in an optically transparent thin-layer electrochemical cell at potential of -0.2 V. The final reduced cyt c exhibits split Q bands at 542, and 575 nm. When cyt c diffused inside TOAB layer, the hydrophobic interaction causes protein structure changes, and affects the iron binding sphere. From the spectrum of the reduced form, we conclude it is a low-spin, five-coordinate ferrous heme.
Gold salt, HAuCl4 can be reduced in cyt c solution and gold nanocrystals were formed from this reduction. Transmission electron microscopy (TEM) images showed distorted spherical shapes of gold nanoparticles were formed with excess Cl ions. In the presence of Br- ions, multiple shapes such as triangular, hexagonal nanoplates, decahedral particle and nanorod were formed. Iodide appears to prevent the formation of gold nanocrystals. At pH 3, the Cl- containing cyt c- HAuCl4 solution showed multiple shapes of gold nanocrystals, and TEM images showed gold nanocrystals were formed within the polypeptide.
Using cyt c as a reducing agent the sizes and shapes of gold nanocrystals are dominated by the nucleation and growth rate which can be fine-tuned by varying reduction potential, temperature, and pHs.

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