State Key Lab for Advanced Metals and Materials, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, PR China.
ACS Appl Mater Interfaces. 2013 Jun 26;5(12):5700-8. doi: 10.1021/am401118r. Epub 2013 Jun 10.
Oligonucleotides such as siRNA and plasmid DNA (pDNA) have great potential for gene therapies. Multifunctional, environment-resistant carriers with imaging capabilities are required to track the assembly and disassembly of oligonucleotides, monitor the delivery processes, and develop new delivery systems. Conjugated polymers and oligomers can potentially be used as novel materials for functional nanocarriers with both delivery and imaging abilities. In this work, a novel π-conjugated oligomer 4,7-(9,9'-bis(6-adenine hexyl)fluorenyl)-2,1,3-benzothiadiazole (OFBT-A) modified with nucleotide adenine (A) groups in its side chains is synthesized and characterized. Fluorescent nanoparticles based on the π-conjugated oligomers OFBT-A are developed as novel functional nanocarriers for oligonucleotides. Single-stranded DNA (ssDNA) TR-T5 labeled with Texas Red (TR) fluorescent dye is selected as a model payload oligonucleotide. The capture abilities and stability of OFBT-A are investigated by monitoring the fluorescence resonance energy transfer (FRET) efficiency between the OFBT-A nanoparticles and TR labels in solution. The OFBT-A/TR-T5 composites are stable in solution at high ionic strengths (0-500 mM) and have a wide working pH range, from 3.0 to 9.5. The in vitro profile demonstrates that the release of the TR-DNA is induced by the ssDNA A43, which has a high charge density. The release process is monitored by measuring the changes in FRET efficiency and fluorescence color for the OFBT-A/TR-T5 composites. Using this carrier, the uptake of TR-DNA by A549 lung cancer cells is observed. Both the OFBT-A nanoparticles and the OFBT-A/TR-T5 composites show high cytocompatibility. We anticipate that these novel functional nanocarriers will provide a safe strategy for monitoring the gene delivery process.
寡核苷酸，如 siRNA 和质粒 DNA（pDNA），在基因治疗方面具有巨大的潜力。需要具有成像功能的多功能、环境抗性载体来跟踪寡核苷酸的组装和拆卸，监测递药过程，并开发新的递药系统。共轭聚合物和低聚物有可能被用作具有递药和成像功能的新型功能纳米载体材料。在这项工作中，我们合成并表征了一种新型的π-共轭寡聚物 4,7-(9,9'-双（6-腺嘌呤己基）芴基）-2,1,3-苯并噻二唑（OFBT-A），其侧链上带有核苷酸腺嘌呤（A）基团。我们开发了基于 π-共轭寡聚物 OFBT-A 的荧光纳米颗粒作为新型功能纳米载体来递寡核苷酸。选择带有 Texas Red（TR）荧光染料的单链 DNA（ssDNA）TR-T5 作为模型负载寡核苷酸。通过监测 OFBT-A 纳米粒子与溶液中 TR 标记物之间的荧光共振能量转移（FRET）效率，研究了 OFBT-A 的捕获能力和稳定性。OFBT-A/TR-T5 复合物在高离子强度（0-500 mM）下和宽工作 pH 值范围内（3.0-9.5）在溶液中稳定。体外研究表明，具有高电荷密度的 ssDNA A43 可诱导 OFBT-A/TR-T5 复合材料中 TR-DNA 的释放。通过测量 OFBT-A/TR-T5 复合材料的 FRET 效率和荧光颜色变化来监测释放过程。使用这种载体，观察到 A549 肺癌细胞摄取 TR-DNA。OFBT-A 纳米粒子和 OFBT-A/TR-T5 复合材料均显示出较高的细胞相容性。我们预计这些新型功能纳米载体将为监测基因递药过程提供一种安全的策略。
