Abstract：
Matrix metalloproteinase 2 (MMP-2) has been considered a promising molecular biomarker for cancer diagnosis due to its related dysregulation. In this work, a core-satellite structure-powered ratiometric surface-enhanced Raman scattering (SERS) nanosensor with high sensitivity and specificity to MMP-2 was developed. The SERS nanosensor was composed of a magnetic bead encapsulated within a 5,5\'-dithiobis(2-nitrobenzoic acid) (DTNB)-labeled gold shell as the capture core and a 4-mercaptobenzonitrile (MBN)-encoded silver nanoparticle as the signal satellite, which were connected through a peptide substrate of MMP-2. MMP-2-triggered cleavage of peptides from the core surface resulted in a decrease of the SERS intensity of MBN. Since the SERS intensity of DTNB was used as an internal standard, the reliable and sensitive quantification of MMP-2 activity would be realized by the ratiometric SERS signal, with a limit of detection as low as 2.067 ng/mL and a dynamic range from 5 to 100 ng/mL. Importantly, the nanosensor enabled a precise determination of MMP-2 activity in tumor cell secretions, which may provide an avenue for early diagnosis and classification of malignant tumors.
摘要：
基质金属蛋白酶2（MMP-2）由于其相关的失调而被认为是癌症诊断的有前途的分子生物标记。在这项工作中,开发了一种对MMP-2具有高灵敏度和特异性的核心-卫星结构功率比率测量表面增强拉曼散射（SERS）纳米传感器。SERS纳米传感器由封装在5,5'-二硫代双（2-硝基苯甲酸）（DTNB）标记的金壳中的磁珠组成，作为捕获核和4-巯基苄腈（MBN）编码的银纳米颗粒作为信号卫星，它们通过MMP-2的肽底物连接。MMP-2触发的肽从核心表面的裂解导致MBN的SERS强度降低。由于DTNB的SERS强度被用作内标，MMP-2活性的可靠和灵敏的定量将通过比率SERS信号来实现，检出限低至2.067ng/mL，动态范围为5至100ng/mL。重要的是,纳米传感器能够精确测定肿瘤细胞分泌物中的MMP-2活性，这可能为恶性肿瘤的早期诊断和分类提供了途径。
