DNA-dye conjugates for controllable H* aggregation
DNA-dye conjugates for controllable H* aggregation
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DOI：
10.1021/ja021153k
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发表时间：
2003-02-26
影响因子：
15
通讯作者：
Komiyama, M
中科院分区：
文献类型：
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作者：
Asanuma, H;Shirasuka, K;Komiyama, M
由含有多个甲基红部分的DNA偶联物成功合成了预定大小的甲基红H-星形聚集体。在单链状态下，浅色性随着掺入染料的数量单调增加：涉及六个甲基红的共轭物的最大峰出现在415 nm处，相对于单体跃迁的位移高达69 nm（3435 cm（-1））。这种大的浅染性伴随着条带的变窄，清楚地表明H-星形聚集体在单链中形成。在较高的离子强度下进一步促进H-星形聚集。然而，当在Tm以下加入互补DNA时，该H-星形带消失，并在448 nm处出现新的峰，表明聚集结构因双链体形成而改变。这种光谱变化是完全可逆的，因此在415 nm处的H星带再次出现在Tm以上。因此，聚集的结构可以通过DNA双链体的形成和解离来可逆地控制。
Methyl Red H-star aggregate of predetermined size is successfully synthesized from the DNA conjugate involving multiple Methyl Red moieties in sequence. In the single stranded state, hypsochromicity monotonically increases with the number of incorporated dyes: the peak maximum of the conjugate involving six Methyl Reds appears at 415 nm, and the shift is as great as 69 nm (3435 cm(-1)) with respect to the monomeric transition. This large hypsochromicity accompanied by the narrowing of the band clearly demonstrates that H-star aggregate is formed in the single strand. H-star aggregation is further promoted at higher ionic strength. Upon addition of complementary DNA below the T-m, however, this H-star band disappears and a new peak appears at 448 nm, indicating that aggregated structure is changed by the duplex formation. This spectral change is completely reversible so that the H-star band at 415 nm appears again above T-m. Thus, aggregated structure can be reversibly controlled by the formation and dissociation of the DNA duplex.