pH敏感型二氧化硅纳米载体的制备研究

Preparation of pH-Sensitive Silica Nanocarriers

利用肿瘤弱酸环境引发功能化中空介孔纳米载体的电荷反转,使其具有pH刺激敏感。通过CTAB制备软模板并在其表面沉积TEOS和Si-69硅烷偶联剂制备得到多腔介孔纳米载体,并对其功能化修饰。软模板是粒径约为180 nm的实心球体,DLS、TEM、BET数据显示最终制备得到介孔为3.1 nm、粒径约为200 nm的多腔介孔纳米载体,红外光谱和拉曼光谱说明成功的进行了功能化修饰,最后通过在不同pH的PBS中表征纳米载体的Zeta电位数据,显示pH 7.4、8.0、9.0条件中该纳米载体的Zeta电位分别(-21.5±0.32)、(-23.8±0.21)、(-25.3±0.33)mV,但是在pH 6.0、5.0条件下电位反转为(+6.2±0.41)、(+7.1±0.4)mV。多腔介孔纳米载体的空腔使其具有更大的载药量,带负电荷的纳米载体具有更长的血液循环时间,而该纳米粒子在弱酸环境下的电荷反转能力,使其能够在肿瘤组织富集,从而具有靶向功能提高药效。

Charge reversal of functionalized hollow mesoporous nanocarriers in tumor weak acid environment and make them sensitive to pH stimulation.The soft template was prepared by CTAB,TEOS and Si-69 silane coupling agent were deposited on the surface of the soft template to prepare the multi-cavity mesoporous nanocarriers,and its functionalization was modified.The soft template was a solid sphere with a particle size of about 180 nm.DLS,TEM and BET data showed that a multi-cavity mesoporous nano-carrier with a mesopore of 3.1 nm and a particle size of about 200 nm was finally prepared.IR and Raman spectra indicated that the functional modification was successfully carried out.Finally,the Zeta potential data of the nanocarrier were characterized in PBS with different pH values.It showed that the Zeta potentials of the nanocarrier were(-21.5±0.32),(-23.8±0.21),(-25.3±0.33)mV at pH 7.4,8.0,9.0,respectively.But at pH 6.0,5.0,the potential changes to(+6.2±0.41),(+7.1±0.4)mV.The cavity of the multi-cavity mesoporous nanocarrier enabled it to have a larger drug load,and the negatively charged nanocarrier had a longer blood circulation time.Moreover,the charge reversal of the nanoparticle in the weak acid environment enables it to accumulate in the tumor tissue,and thus has the targeting function to improve the drug efficacy.