本文以分散粒子動力學法研究DNA修飾金奈米粒子之自我組裝象，並在模擬過程中分析適當模擬盒大小、不同形貌下的DNA-AuNPs聚集形態效應，以及利用不同DNA鏈長，所產生的團簇大小及形貌變化。由模擬結果顯示，不同形貌DNA-AuNPs的平均聚集數會隨著嫁接在金奈米粒子上的DNA spacer是否完整延展而改變大小；當相互雜交的粒子數所佔的體積分率愈接近 1:1，其平均聚集數也將會大幅增加。將DNA鏈長增長，使得DNA鏈長與金奈米粒徑的比值變大，平均聚集數卻沒有線性成長，模擬當中發現DNA鏈長增為15-mer時，DNA spacer卻因撓度過高，而在尾端產生纏繞現象，無法有效雜交。由迴旋半徑與偏球率則觀察到，隨著DNA鏈長的增加，會使整體團簇結構由橢圓狀轉為類球狀。

In this paper, self-assembly behavior of modified gold nanoparticles with oligonucleotides was studied by using dissipative particle dynamics(DPD) . During the simulation, the influence of the appropriate size of simulation box, the aggregation of different morphology of the DNA-AuNPs and the different length of DNA chain on the resulting cluster size and the change of morphology was investigated individually. The results showed that the mean aggregation number change of the the DNA-AuNPs of different morphologies with the DNA spacer, completely grafted on gold nanoparticles is dependent upon whether the chain is perfectly extended or not.When the volume fraction of beads of hybridization is close to fifty-fifty, the mean aggregation number will increased dramatically. As the DNA chain was enlarged, the ratio of the DNA chain and the diameter of AuNPs increased, while the mean aggregation number does not increase linearly.Moreover, as the oligonucleotide numbers is increased to 15-mer, attributed to the soft flexibility of DNA spacer, the DNA spacer exhibited tangling phenomenon with inefficient hybridization. It was found that as the DNA chain length increased, the overall cluster structure will transforme from ellipsoid-like to spheroid-like by using radius of gyration and asphericity.

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