Detection of micrometastases in lung cancer with magnetic nanoparticles and quantum dots

Abstract

Detection of micrometastases plays an important role in early-stage and recurrent cancer diagnosis. In the study, a new method of screening micrometastases of lung cancer in peripheral blood by magnetic nanoparticles (MNPs) and quantum dots (QDs) was developed to achieve early diagnosis and recurrence prevention. MNPs were prepared by combining miniemulsion polymerization and Stöber coating methods. QDs were prepared by using Cd(Ac)₂ · 2H₂O and oxygen-free NaHTe with thioglycolic acid as the stabilizer. The carbodiimide-mediated condensation method was used to couple pan-cytokeratin (pan-ck) antibody (Ab) to the surface of the MNPs, and Lunx and SP-A Abs to the surface of the QDs. After four kinds of epithelial tumor cells were enriched by MNPs coupled with pan-ck Ab (MNP-pan-ck), lung cancer cells A549 and SPC-A-1 were successfully identified by QDs with double-labeled Abs. Finally, 32 patients with non-small cell lung cancer (NSCLC) were collected, out of 26 cases with the enriched circulating tumor cells (CTCs), 21 cases were successfully identified by QDs. Therefore, a new method was established in which MNP-pan-ck collected CTCs and QDs with double-labeled Abs could be used simultaneously to identify CTCs from NSCLC patients.

Keywords:

• micrometastases
• lung cancer
• magnetic nanoparticles
• quantum dots
• Lunx
• SP-A

Acknowledgments

This study was supported by a grant from the Science and Technology (No 20082123) of Jilin Province, China. The authors are grateful to the Key Laboratory of Surface and Interface Chemistry of Jilin University for the kind provision of the method of preparation and modification of Fe₃O₄/polystyrene MNPs (patent delegation NO CN100425627C) and aqueous soluble CdTe QDs, and to Dr Wei Zhang (Chinese Academy of Medical Sciences) for providing the pan-ck Ab.

Disclosure

The authors report no conflicts of interest in this work.