Biomedical Engineering Reference
In-Depth Information
8
Label-Free Biochips
Anis N. Nordin
1,2
1
Biosensors and Bioelectronics Centre, IFM, Linköping University,
Linkoping Sweden
2
Department of Electrical and Computer Engineering, International Islamic
University Malaysia, Malaysia
Abstract
Artifact-free sensing or label-free biosensors are fast gaining popularity today due
to their simple preparation methods, accuracy and noise-free results. h is chapter
focuses on the usage of label-free sensors for biological applications. h ere are
various ways for non-tagged sensing, but the most common are using electro-
chemical and acoustic wave sensors. A brief overview on the operating principles
for both sensors is described in this chapter such that even non-chemists or biolo-
gists can easily understand the device concept. State-of-the-art example devices
for both electrochemical and acoustic wave sensors are also explained so that the
reader can be updated with the current technology. Special emphasis is given to
sensors that can be fabricated using microelectromechanical (MEMS) systems
techniques, a fabrication process that is adapted from the commercial integrated
circuits for interdisciplinary applications such as healthcare diagnostics or toxicity
detections. MEMS biochips are getting increased attention from researchers due
to its miniature size, portability and parallel processing capabilities.
Keywords:
Biosensors, MEMS, Bio-MEMS, label-free, electrochemical, bulk
acoustic wave (BAW), surface acoustic wave (SAW), FBAR
8.1 Introduction
h ei eld of biosensors has been known for the past sixty years, with numer-
ous available commercial devices available in the market. Amongst the
