Magnetic-Based Microfluidic Device for On-Chip Isolation and Detection of Tumor-Derived Exosomes

Abstract

Exosomes are membrane-enclosed phospholipid extracellular vesicles, which can act as mediators of intercellular communication. Although the original features endow tumor-derived exosomes great potential as biomarkers, efficient isolation and detection methods remain challenging. Here, we presented a two-stage microfluidic platform (ExoPCD-chip), which integrates on-chip isolation and in situ electrochemical analysis of exosomes from serum. To promote exosomes capture efficiency, an improved staggered Y-shaped micropillars mixing pattern was designed to create anisotropic flow without any surface modification. By combining magnetic enrichment based on specific phosphatidylserine-Tim4 protein recognition with a new signal transduction strategy in a chip for the first time, the proposed platform enables highly sensitive detection for CD63 positive exosomes as low as 4.39 × 10 3 particles/mL with a linear range spanning 5 orders of magnitude, which is substantially better than the existing methods. The reduced volume of sample (30 μL) and simple affinity method also make it ideal for rapid downstream analysis of complex biofluids within 3.5 h. As a proof-of-concept, we performed exosomes analysis in human serum and liver cancer patients can be well discriminated from the healthy controls by the ExoPCD-chip. These results demonstrate that this proposed ExoPCD-chip may serve as a comprehensive exosome analysis tool and potential noninvasive diagnostic platform.

Tumor‐Derived Extracellular Vesicles as a Novel Source of Protein Biomarkers for Cancer Diagnosis and Monitoring

“…We highlight the need for robust study design and comprehensive data reporting, as well as testing of candidate biomarkers against current clinical gold standards in order to demonstrate the validity of this approach. We anticipate that future studies will capitalize on emerging EV isolation techniques such as microfluidic capture devices and asymmetric flow field‐flow fractionation, which may help to increase EV purity and improve assay specificity . TEVs represent an ideal target for clinical application and improvements in EV purification and characterization will ensure that this exciting field of research continues to expand over the next few years.…”

Exosomes for Non‐Invasive Cancer Monitoring

“…In recent years, Xu et al, reported two‐stage microfluidic platform (ExoPCD‐chip) which integrates on‐chip isolation and in‐situ electrochemical analysis of exosomes. The developed system was utilized for the diagnosis of liver cancer patients . In addition, critical are methods to screen panels of exosome‐derived proteins, their post‐translational modifications and RNA targets.…”

The cancer exosomes: Clinical implications, applications and challenges

“…designed an alternating current electrokinetic (ACE) microarray device, which allowed the isolation of glioblastoma‐derived exosomes from a plasma sample (30–50 μl), as well as apparently simplifying processing steps and enabling less time required. Another comprehensive exosome analysis tool and potential noninvasive diagnostic platform, ExoPCD‐chip, is a two‐stage microfluidic platform whose isolation and analysis applied for liver cancer‐derived exosomes as low as 4.39 × 10 3 particles/ml from a serum sample (30 μl) within 3.5 hr . Microfluidic chip is capable to effectively isolate exosomal ingredients as well.…”