Multifunctional Magnetic Particles for Combined Circulating Tumor Cells Isolation and Cellular Metabolism Detection

Abstract

We for the first time demonstrate multi-functional magnetic particles based rare cell isolation combined with the downstream laser desorption/ionization mass spectrometry (LDI-MS) to measure the metabolism of enriched circulating tumor cells (CTCs). The characterization of CTCs metabolism plays a significant role in understanding the tumor microenvironment, through exploring the diverse cellular process. However, characterizing cell metabolism is still challenging due to the low detection sensitivity, high sample complexity, and tedious preparation procedures, particularly for rare cells analysis in clinical study. Here we conjugate ferric oxide magnetic particles with anti-EpCAM on the surface for specific, efficient enrichment of CTCs from PBS and whole blood with cells concentration of 6–100 cells per mL. Moreover, these hydrophilic particles as matrix enable sensitive and selective LDI-MS detection of small metabolites (MW<500 Da) in complex bio-mixtures and can be further coupled with isotopic quantification to monitor selected molecules metabolism of ~50 CTCs. Our unique approach couples the immunomagnetic separation of CTCs and LDI-MS based metabolic analysis, which represents a key step forward for downstream metabolites analysis of rare cells to investigate the biological features of CTCs and their cellular responses in both pathological and physiological phenomena.

Plasmonic silver nanoshells for drug and metabolite detection

“…Matrix-assisted laser desorption/ionization (MALDI) MS has displayed great superiority considering its fast analysis of analytes in seconds, accurate mass measurement for identification, simple sample preparation for broad application, and high sensitivity with low costs for practical use 1,2,5 . Inorganic particles (e.g., silicon 10,11 , carbon 12,13 , metal [14][15][16] , and metal oxide 17,18 ) have been preferred matrices in LDI MS for small metabolites as reported by research groups globally including ours. These particles can control the analytical variations and background signals in the mass region below m/z of 500, achieving the qualitative analysis of small metabolites, such as carbohydrates and amino acids 6,7,19 .…”

“…Isotopic quantification. The isotopes of selected metabolites were introduced as the internal standard for quantification use 17 . Standard solutions of small molecules with different concentrations were employed to plot the calibration curves.…”

Advances in liquid biopsy on-chip for cancer management: Technologies, biomarkers, and clinical analysis

“…By combining the advantages of microfluidics and immunomagnetics, the group was able to optimize the capture rate of CTCs onto glass slides. Recently, a commercial platform was developed by NanoLite Systems based on this innovation, which was used to carry out combined CTCs isolation and cellular metabolism detection[85]. An illustration of the device prototype and the commercial platform are below in Figure 6.…”

A coming era of precision diagnostics based on nano-assisted mass spectrometry

“…1,8,9 Among numerous analytical approaches for omics, mass spectrometry (MS) has become the major tool due to the desirable throughput, sensitivity, and identification capability. [10][11][12][13] To date, the state-of-art MS methods and techniques have advanced omics in all levels * Corresponding Authors: E-mail: jjwan@chem.ecnu.edu.cn, k.qian@sjtu.edu.cn including genomics, 14,15 proteomics, [16][17][18] and metabolomics. [19][20][21] Nowadays, interdisciplinary research is fundamental to achieve real case applications of MS in clinics.…”