Three-Dimensional Magnetic Chip with Extracorporeal Circulation for Circulating Tumor Cell In Vivo Detection and Tumor Growth Inhibition.

Liquid biopsy technology involves taking samples from body fluids in a minimally invasive way and analyzing tumor markers to achieve early diagnosis and efficacy evaluation of tumors. The development of real-time cancer diagnosis and treatment strategies based on liquid biopsy technology is of great significance to cancer management. This paper described an extracorporeal circulation based on a three-dimensional (3D) magnetic chip (3DMC-system) for in vivo detection and real-time monitoring of circulating tumor cells (CTCs). Utilizing biofunctionalized magnetic nanospheres (MNs) with CTC recognition function, this 3DMC-system could effectively achieve the real-time monitoring of CTCs in vivo with good stability and strong anti-interference. Compared with in vitro CTC detection, in vivo detection could not only detect more CTCs but also detect the presence of CTCs in the blood at an early stage of the tumor, when tumor metastasis is not observed in imaging. In addition, due to the flexibility of the chip design, the system can easily add a treatment module to integrate cancer diagnosis and treatment together. With good biocompatibility and high stability, this 3DMC-system is expected to provide a new personalized medical program for cancer patients.

Single-Nanoparticle Collision Electrochemistry Biosensor Based on an Electrocatalytic Strategy for Highly Sensitive and Specific Detection of H7N9 Avian Influenza Virus.

Single-nanoparticle collision electrochemistry (SNCE) has gradually become an attractive analytical method due to its advantages in analytical detection, such as a fast response, low cost, low sample consumption, and in situ real-time detection of analytes. However, the biological analyte's direct detection based on the SNCE blocking mode has the problems of low sensitivity and specificity. In this work, an SNCE biosensor based on SNCE electrocatalytic strategy was used for the detection of H7N9 AIV. Nucleic acid aptamers were introduced to recognize the target virus (H7N9 AIV). After the recognition event, ssDNA1 was released and hybridized with another ssDNA2. Owing to the nicking endonuclease Nt.AlwI-mediated target nucleic acid cyclic amplification, one virus particle can indirectly induce the release of 4.2 × 106 Au NPs that can be counted by the SNCE electrocatalytic strategy. The high conversion efficiency greatly improved the detection sensitivity, and the detection limit was as low as 24.3 fg/mL. Therefore, the constructed biosensor can achieve a highly sensitive and specific detection of H7N9 AIV and show a great potential in bioanalytical application.