Using microcantilever deflection to detect HIV-1 envelope glycoprotein gp120

Lam, Yee; Abu-Lail, Nehal I.; Alam, Munir S.; Zauscher, Stefan

doi:10.1016/j.nano.2006.10.002

« Previous Next »Nanomedicine: Nanotechnology, Biology and Medicine
Volume 2, Issue 4 , Pages 222-229, December 2006

Using microcantilever deflection to detect HIV-1 envelope glycoprotein gp120

Yee Lam, MS
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina, USA
- Center for Biomolecular and Tissue Engineering, Duke University, Durham, North Carolina, USA
- Center for Biologically Inspired Materials and Materials Systems, Durham, North Carolina, USA
Nehal I. Abu-Lail, PhD
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina, USA
- Center for Biologically Inspired Materials and Materials Systems, Durham, North Carolina, USA
Munir S. Alam, PhD
- Human Vaccine Institute, Duke University, Durham, North Carolina, USA
- Center for Biomolecular and Tissue Engineering, Duke University, Durham, North Carolina, USA
- Center for Biologically Inspired Materials and Materials Systems, Durham, North Carolina, USA
Stefan Zauscher, PhD
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina, USA
- Center for Biomolecular and Tissue Engineering, Duke University, Durham, North Carolina, USA
- Center for Biologically Inspired Materials and Materials Systems, Durham, North Carolina, USA
- Corresponding author. Mechanical Engineering and Materials Science, Duke University, Box 90300, Durham, NC 27708, USA. Tel.: +1 919 660 5630; fax: +1 919 660 5409.

Received 2 August 2006; accepted 18 October 2006.

Abstract

Microcantilevers have been used over the last decade to detect biomolecules from solution. Specific binding events on one surface of the microcantilever create a differential stress, resulting in measurable deflection. Here we use this principle to detect human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) gp120 from solution. We observed deflections approximately twice that of the baseline (in PBS) upon specific binding of gp120 to cantilevers decorated on one side with monoclonal antibodies (mAbs) A32 or T8. Subsequent incubation with mAb 17b (known to bind an A32-induced epitope on gp120) further increased deflection of A32- but not T8-presenting cantilevers. This work shows the capability of microcantilever deflection sensors to detect an induced-fit interaction at test concentrations of 8 μg/mL gp120 and 0.17 mg/mL 17b. Further development of this technique could lead to a portable, low-cost device for the effective detection of HIV-1.

Key words: Microcantilever deflection, HIV-1 detection, Induced-fit interactions