Qianxi Zhou,Hao Zhang,Tianyu Zeng,Jiahua Yang,Qizhi Liang,Hai Shi,Yongmei Yin,Genxi Li
The dynamic variation of D-amino acids (D-AAs) in human saliva has great potential as the indicator for individual physiological states and disease progression; however, enantiospecific profiling of D-AAs is a great challenge. In this work, a nanoreactor based on mesoporous hydrogen-bonded organic framework (MHOF) has been fabricated for the enantiospecific profiling of D-AAs. The nanoreactor is prepared by using MHOFs as the scaffold to organize the biocatalytic cascade of D-AA oxidase (DAAO) and horseradish peroxidase (HRP). In the meanwhile, the large, stable, and robust transport channels of MHOFs allow the unimpeded transport of the involved biocatalytic substrates. Once D-AA substrates efficiently transport into MHOFs, the chromogenic reactions of 3,3′,5,5′-tetramethylbenzidine (TMB) and H 2 O 2 can be activated. So, using this MHOF nanoreactor, enantiospecific and visual detection of D-AAs can be achieved. Moreover, the stable nanoreactor can be operated in complex solution and utilized for the profiling of D-AA levels in saliva samples collected from gastric cancer patients, suggesting that D-AAs may be a powerful fingerprint for the diagnosis of gastric cancer. Therefore, the fabricated MHOF-based nanoreactor may provide an emerging tool for the enantiospecific profiling of D-AAs and supports the D-AA fingerprint as the indicator of gastric cancer diagnosis.
Chujun Zheng,Qixia Jiang,Kan Wang,Tangan Li,Wei Zheng,Yuemeng Cheng,Qihong Ning,Daxiang Cui
In this study, we developed a novel magnetic lateral flow assay based on iron oxide decorated with platinum probes (Fe3O4@Pt) for dual-mode detection of gastrin-17 (G-17), which is one of the main biomarkers for early gastric cancer diagnosis. The probe material exhibits both magnetic properties and peroxidase activity. The peroxidase activity enhances the intensity of the brownish coloring of the Fe3O4@Pt probes on the test strip, with a limit of detection of 10 pg mL−1 using the naked eye, which is remarkable for colorimetric lateral flow assays. The magnetic property allows the simple separation and enrichment of the sample, and the signal can be read using a magnetic assay reader for quantitative detection. The linear range for G-17 using the magnetic signal was determined as 10 pg mL−1 to 2200 pg mL−1, and the calculated limit of detection was as low as 3.365 pg mL−1, thereby covering the reference range for G-17. Serum samples were used to validate the test strip, which exhibited high sensitivity, high specificity, and consistency with the results obtained by the enzyme-linked immunosorbent assay method. The entire inspection process using this method can produce results within 35 min and it is simple to operate without requiring strict experimental conditions. This dual-mode lateral flow test strip provides a simple, rapid, and quantitative strategy for detecting G-17, and it may also be valuable in other portable diagnostic applications.
Yi Shi,Jingyi Zhang,Jia He,Donghao Liu,Xiaoyan Meng,Tao Huang,Hua He
Analyzing of tumor markers has become an important means for cancer diagnosis and prevention. In this study, a novel solid phase extraction based on porous magnetic cyclodextrin polymer (MA-CD) was developed and used for detection of trace small molecule gastric tumor markers in urine samples. The adsorption properties of the magnetic cyclodextrin polymer were tested. Through experiments of the solid phase extraction (SPE) at the different condition, the optimal condition was selected to test the two tumor markers by High-performance-liquid chromatography -Diode array detector (HPLC-DAD). The analytical performance of the method showed good accuracy (88.82%–104.34%) and precision (< 3.55%), appropriated detection limits (1.016 and 5.714 μg L −1 ) and linear ranges (0.6–24.0 μg L −1 ) with convenient determination coefficients (> 0.9994). The results demonstrated that the developed approach is efficient, low-cost for gastric tumor markers detection.