在逐层组装的DNA/PAH薄膜中，pH值刺激阳离子染料发生可逆的负载和释放。

The pH stimulated reversible loading and release of a cationic dye in a layer-by-layer assembled DNA/PAH film.

作者信息

Jiang Siguang, Chen Xiaodong, Liu Minghua

机构信息

CAS Key Laboratory of Colloid and Interface Science, Center for Molecular Science, Institute of Chemistry, CAS, Beijing 100080, People's Republic of China.

出版信息

J Colloid Interface Sci. 2004 Sep 15;277(2):396-403. doi: 10.1016/j.jcis.2004.04.008.

DOI:10.1016/j.jcis.2004.04.008

PMID:15341851

Abstract

Through the layer-by-layer (LbL) deposition method, DNA was assembled into an ultrathin film with a cationic poly(allylamine hydrochloride) (PAH). The loading and release of a typical cationic dye, 5, 10, 15, 20-tetrakis(4-N-methylpyridyl)porphine-tetra-(p-toluenesulfonate) (TMPyP), in the DNA/PAH films were investigated. It has been found that the LbL-assembled DNA/PAH film was very stable in both acidic and alkaline solutions. Stimulated by the pH change of the dye solution, the dye can be easily loaded into or released from the DNA/PAH film. In an alkaline solution, the dye could be rapidly loaded into the DNA/PAH film at room temperature, while in an acidic solution, the dye could be rapidly released. The mechanism of such pH-stimulated loading and release in the DNA/PAH film was discussed. It was further observed that the loading and release of the dye in the DNA/PAH film was reversible upon pH change and the process could be repeated many times.

摘要

通过层层（LbL）沉积法，将DNA与阳离子聚（烯丙胺盐酸盐）（PAH）组装成超薄膜。研究了典型阳离子染料5,10,15,20-四（4-N-甲基吡啶基）卟啉-四（对甲苯磺酸盐）（TMPyP）在DNA/PAH膜中的负载和释放情况。已发现LbL组装的DNA/PAH膜在酸性和碱性溶液中都非常稳定。受染料溶液pH变化的刺激，染料可轻松负载到DNA/PAH膜中或从其中释放出来。在碱性溶液中，染料可在室温下迅速负载到DNA/PAH膜中，而在酸性溶液中，染料可迅速释放。讨论了DNA/PAH膜中这种pH刺激的负载和释放机制。进一步观察到，DNA/PAH膜中染料的负载和释放在pH变化时是可逆的，并且该过程可重复多次。