Silicon nanowire biosensors for CTC detection

Silicon nanowires/nanoribbons (SiNW/SiNR) offer a highly sensitive and label free detection principle for biochemical applications. The technique has potential in low-concentration detection as well as in scaling down the size of complete analysis systems to provide rapid on-site detection.

PROJECT SUMMARY

  • Grant: Knut and Alice Wallenberg foundation (KAW)
  • Duration: 1st January 2012 – 31th December 2016
  • Consortium: 7 Swedish partners from KTH, Uppsala University, SciLifeLab, Karolinska Institutet and Acreo Swedish ICT
  • Coordinator: Jan Linnros, KTH
  • Project Leader at Acreo Swedish ICT: Per Björk

Project Description

Currently, we are aiming at developing a new technique based on silicon nanowires/nanoribbons (SiNW/SiNR) for fast detection of circulating tumour cells (CTC) in blood samples. Prospective tumour cells will be isolated, counted and identified based on detection of protein markers and transcripts.

The sensor function of SiNW/SiNR is similar to that of a MOS-transistor where the sense current is dependent on the gate voltage. For SiNW/SiNR the current is dependent on the surface charges of the thin nanowires. When charged molecules are present at the surface, the conductance of the nanowire is affected which is detected as a change in channel current. The SiNW/SiNR are fabricated using standard CMOS technology which together with the label free electrical detection method enables mass production of fast, reproducible and low-cost devices for disposable uses.

Principle for SiNW detection.

Functionalization of the SiNW/SiNR with antibodies and DNA probes activates the sensor for detection of specifically charged target molecules. Using multiple functionalized SiNW/SiNR, multiplexed readout setup and a microfluidic delivery system in hard (silicon, resists and plastics) and soft (PDMS) materials, the sample volume can be minimized and different target molecules can be detected simultaneously in order to take full advantage of the potentially very high detection sensitivity.

Acreo is involved in the integration of the different chip functionalities, design and fabrication of the nanowire chip as well as the microfluidic delivery system, and development of the multiplexed read-out system.

External homepage: 
http://www.kth.se/en/ict/2.8781/research/nano-silicon/kaw-2012