2014年7月12日 訊 /生物谷BIOON/ --細菌性感染往往會引發機體發燒及疼痛,但是利用抗生素就可以快速殺滅細菌阻斷感染性疾病的發生,但是隨著抗生素的使用,細菌就會慢慢對抗生素產生一定的耐受性,從而導致抗生素的失效。
近日,刊登在國際雜誌ACS Applied Materials & Interfaces上的一篇研究論文中,來自新加坡國立大學的研究人員開發出了一種抵禦細菌感染的新型武器-DNA「金字塔」納米結構,這種新型的金字塔納米結構或許可以將細菌「罩住」從而比藥物更為高效地將其殺滅。
研究者David Leong博士說道,有些感染性的病原體會隱藏很久,並不會被人類機體所識別,有時候抗生素也對其束手無策;工程化的納米藥物結構就可以運輸藥物直至細菌細胞中對其進行精準殺滅作用,但是這種運輸載體還具有一定的毒性,因此這項研究中研究人員利用DNA為基礎構建了一種安全有效的藥物運輸工具。
這項研究中,研究者成功構建了小型的DNA「金字塔」納米結構,其足夠小以至於可以進行成千上萬次地藥物運輸,隨後研究者用螢光標記吸附於這種金納米材料上,同時將藥物放線菌素D裝載於DNA「金字塔」納米結構上;在對常見細菌大腸桿菌和金黃色葡萄球菌進行檢測後,當這種運輸結構進入細菌細胞釋放藥物後,研究者就可以對其進行追蹤,結果顯示,這種DNA「金字塔」納米結構攜帶的藥物放線菌素D可以殺滅65%的金黃色葡萄球菌和48%的大腸桿菌,而單獨使用放線菌素D則可以殺滅42%的金黃色葡萄球菌及14%的大腸桿菌。(生物谷Bioon.com)
Novel Theranostic DNA Nanoscaffolds for the Simultaneous Detection and Killing of Escherichia coli and Staphylococcus aureus
Magdiel I. Setyawati ‡, Rajaletchumy Veloo Kutty ‡, Chor Yong Tay ‡, Xun Yuan ‡, Jianping Xie *‡, and David T. Leong *‡§
A novel theranostic platform is made by utilizing a self-assembled DNA nanopyramid (DP) as scaffold for incorporation of both detection and therapeutic moieties to combat bacterial infection. Red-emissive glutathione-protected gold nanoclusters (GSH-Au NCs) were used for bacterial detection. Actinomycin D (AMD) that was intercalated on the DP scaffold was used as therapeutic agent. This results in the formation of theranostic DPAu/AMD. Model bacteria Escherichia coli and Staphylococcus aureus were found to be readily taken in the DPAu/AMD and be susceptible to its killing effect. In addition, DPAu/AMD was observed to outperform the free AMD in killing infectious bacteria. The degradation of the DP structure by DNase was found to be responsible for the release of AMD and the effective killing effect of the infectious bacteria. This novel strategy presents a basic platform for future improvements to detect infectious bacteria and treatment.