Sun Yuanjie, Tao Liang, Ma Ying, Yang Shuya, Zhang Xiyang, Jin Boquan, Zhang Zhujun, Yang Kun
Department of Immunology, The Fourth Military Medical University, Shaanxi, China.
Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Shaanxi, China.
Front Chem. 2020 Sep 7;8:802. doi: 10.3389/fchem.2020.00802. eCollection 2020.
Cystatin C is an important cysteine protease inhibitor in the human body and is proposed as a new indicator of glomerular filtration rate for the detection of kidney damage. In this article, we report an ultra-sensitive, simple, and rapid chemiluminescence immunoassay method for cystatin C detection using functionalized mesoporous silica nanoparticles. After a three step hydrolysis, the amino-functionalized MSN encapsulating dye resulted in a hydrophobic environment for fixing the dye and amino groups for biological modification. The NaIO immobilization method maintained the activity of the antibody notably well. The sandwich immunoassay using two monoclonal antibodies was chosen for its selectivity. The analysis demonstrated that the detection upper was 0.0029 ng/mL and linear relationship within the range of 0.0035-0.5 ng/mL ( = 0.9936). The relative standard deviation (RSD) for 11 parallel measurements of 0.25 ng/mL CysC was 4.7%. The automated chemiluminescence analyzer could detect 96 wells continuously. The results demonstrated that this method is ultra-sensitive, simple, and rapid for detecting cystatin C.
胱抑素C是人体中一种重要的半胱氨酸蛋白酶抑制剂，被提议作为检测肾脏损伤的肾小球滤过率的新指标。在本文中，我们报道了一种使用功能化介孔二氧化硅纳米颗粒检测胱抑素C的超灵敏、简单且快速的化学发光免疫分析方法。经过三步水解后，包封染料的氨基功能化介孔二氧化硅产生了一个用于固定染料的疏水环境以及用于生物修饰的氨基。NaIO固定方法能显著保持抗体的活性。选择使用两种单克隆抗体的夹心免疫分析是因其具有选择性。分析表明，检测上限为0.0029 ng/mL，在0.0035 - 0.5 ng/mL范围内呈线性关系（ = 0.9936）。对0.25 ng/mL胱抑素C进行11次平行测量的相对标准偏差（RSD）为4.7%。自动化学发光分析仪可连续检测96孔。结果表明，该方法用于检测胱抑素C具有超灵敏、简单且快速的特点。
