半導體奈米粒子表面修飾細胞核定位訊號應用於基因轉染之研究

Nuclear Localization Signal modified QDs as gene delivery carriers

吳佳璇(Chia-Hsuan Wu)

指導教授 ： 陳家俊

國立臺灣師範大學/理學院/化學系/碩士(2003年)

摘要

硒化鎘/硫化鋅半導體無機奈米粒子即為半導體量子點，其強螢光放光特性成為相當適合於生物系統觀測的發光團，將水溶性半導體奈米粒子表面修飾上具有功能性的訊息後，便能夠辨認生物系統中的分子。具有細胞核定位訊號的胺基酸（簡稱NLS）已經普遍用於增加DNA進入細胞核內的機會，利用QD表面修飾NLS，此胺基酸具有正電荷與帶有負電荷的DNA以非共價吸附。細胞內的影像追蹤發現表面修飾有NLS的QD粒子聚集在細胞核周邊的位置，顯示其所攜帶的質體DNA位在細胞核膜附近。相較於沒有修飾NLS的QD粒子則散亂的分佈在細胞質內。表面修飾有NLS的QD及其攜帶的轉染基因所顯現的轉染效率亦較沒有修飾NLS的QD為高。

關鍵字

半導體奈米粒子 ； 細胞核定位訊號

並列摘要

Highly luminescent core-shell CdSe-ZnS semiconductor nanocrystals, also known as quantum dots (QDs), are bright inorganic fluorophores suitable for biological imaging. Functionalization of the water-soluble QD surface allows the formation of QD bioconjugates that can bind to target molecules. Nuclear localization sequence (NLS) peptides have been widely used to enhance the nuclear uptake of DNA. Noncovalent attachment of the positive charged NLS-modified QD is performed through electrostatic interactions with the negatively charged DNA. Evaluation of intracellular trafficking showed NLS-modified QDs localize to perinucleus, suggesting that a high number of plasmid DNA molecules are closely localized to the nuclear envelope; unmodified QDs, however, disperse randomly within the cytoplasm. Evaluation of transfection showed higher expression efficiency with QD-NLS-pDNA conjugates than with unmodified QDs-pDNA.

並列關鍵字

QD ； NLS

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