基于聚丙烯酸交联组装单层SiO_2纳米粒粗糙表面及其细胞捕获

Rough Surface of One-layer SiO_2 Nanoparticles Assembled by Polyacrylic Acid Cross-linking and Its Cell Capture

以玻片为载体(Subs),聚丙烯酸(PAA)为交联剂和柔性体,SiO_2纳米粒为刚性体,人B淋巴细胞瘤Ramos细胞为目标细胞,TD05适体为细胞捕获配体(Apt),在载体上交联组装了结构为Subs-PAA1-SiO_2-PAA2-Apt的细胞捕获支架。该支架既有小尺度的刚性结构,即SiO_2纳米粒,又有柔性结构,即聚丙烯酸PAA1和PAA2。前者增加了载体的粗糙度,而后者不仅能够固载多重捕获配体,也能够有效降低宏观载体对细胞捕获的空间位阻。结果表明,支架具有良好的纳米粒结构,未发现纳米粒的融合甚至消失;支架的特异性捕获是非特异性吸附的16倍,被捕获细胞表现出较高的纯度;同时,支架具有较高的捕获效率,捕获细胞数是通常的单层刚性纳米粒支架的8.3倍。由此表明,该文构建的结构新颖的纳米粒柔性支架实现了目标细胞的高效率、高纯度捕获,将为肿瘤细胞的分析检测提供可靠的样本。

A cell capture scaffold with a structure of Subs - PAA1 - SiO2 - PAA2 - Apt was assem- bled by using a glass slide as substrate carrier （Subs）, polyelectrolyte polyacrylic acid （PAA） as cross-linking agent and flexible body, SiO2 nanoparticles as rigid body, and TD05 aptamer（Apt） as capture ligand of objective cell Ramos. Here there are a small scale and rigid structure （ i. e. SiO2 nanoparticle）, but also a flexible structure（ i. e. polyacrylic acid PAA1 and PAA2）. The former in- creased the roughness of carrier, and the latter could not only immobilized the multi-ligand Apt, but also decreased the steric hindrance from the scaffold itself and the carrier for cell capture. The results indicated that the as-assembled scaffold had a good nanoparticle structure and fusing even disappea- ring of the nanoparticle structure was not found. For the scaffold, its specific capture was 16 times of the non-specific adsorption, and the captured cell showed a higher purity. Meanwhile the captured cell has also a higher captureefficiency, and the capture cell number was 8.3 times of that of the usu- al rigid scaffold with one-layer nanoparticle. It was shown that the nanoparticle flexible scaffold with a novel structure was fabricated, which could realize the high purity and the high efficiency for cell capture.