Shape-Coded Silica Nanotubes for Multiplexed Bioassay: Rapid and Reliable Magnetic Decoding Protocols

Abstract

Aims: The recent development of 1D barcode arrays has proved their capabilities to be applicable to highly multiplexed bioassays. This article introduces two magnetic decoding protocols for suspension arrays of shape-coded silica nanotubes to process multiplexed assays rapidly and easily, which will benefit the minimization and automation of the arrays. Methods: In the first protocol, the magnetic nanocrystals are incorporated into the inner voids of barcoded silica nanotubes in order to give the nanotubes magnetic properties. The second protocol is performed by trapping the barcoded silica nanotubes onto streptavidin-modified magnetic beads. Results: The rapid and easy decoding process was demonstrated by applying the above two protocols to multiplexed assays, resulting in high selectivity. Furthermore, the magnetic bead-trapped barcode nanotubes provided a great opportunity to exclude the use of dye molecules in multiplexed assays by using barcode nanotubes as signals. Conclusion: The rapid and easy manipulation of encoded carriers using magnetic properties could be used to develop promising suspension arrays for portable bioassays.

Keywords::

• AAO
• anodic aluminum oxide
• barcode
• bioassay
• cancer marker
• magnetic decoding
• multiplex assay
• silica nanotubes
• suspension array

Financial & competing interests disclosure

This work was supported by the University of Maryland, Integrated Nanobio Seed Grant through the Maryland Department of Business and Economic Development, the NIH and the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korean government (MEST, R31-2008-000-10071-0, WCU). This research was also supported by the Kyungwon University Research Fund in 2009. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Acknowledgements

The authors would like to thank X Bai for her help with the magnetic nanocrystals loading, and Professor Keating and her group for their help with the NBSee software.

Additional information

Funding

This work was supported by the University of Maryland, Integrated Nanobio Seed Grant through the Maryland Department of Business and Economic Development, the NIH and the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korean government (MEST, R31-2008-000-10071-0, WCU). This research was also supported by the Kyungwon University Research Fund in 2009. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.