Localized Functionalization and Integration with Microfluidics for Multiplexed Biomolecule Detection using Silicon Nanoribbon-FET Sensors

• Biological processes causing different medical conditions are seldom characterized by the simple presence or absence of a single biomarker molecule and it can be expected that biosensors with options for multiplexed detection of a panel of analytes will be required for the development of bed-side diagnostic/prognostic tools for personalized healthcare. One sensor technology with potential to be used for label-free detection of biomolecules is based on Silicon Nanoribbon Field-Effect Transistors (SiNR FET). In this study, the possibilities for multiplexed detection of biomolecules have been explored by the integration of a SiNR FET device with a microfluidic system, in combination with localized immobilization of receptor molecules using a microdispensing instrument. SiNR FET devices were fabricated using CMOS technology and integrated with a microfluidic delivery system composed of channels defined in an SU-8 layer, covered with a PDMS lid. Switching between buffer solutions of different pH was used to demonstrate that the microfluidic system could be used for controlled sample delivery. The shift in conductance of the sensing wire upon change of pH showed that the SiNR FET devices were functional. Protocols for surface functionalization and biomolecule immobilization were evaluated using model systems based on synthetic complementary DNA oligonucleotides and the protein A-derived Z domain and its interaction with immunoglobulin G. The study demonstrates that localized immobilization of biomolecules on silicon nanoribbons can be achieved, opening up for multiplexed detection of analytes and improved possibilities for referencing.

Keyword

Bioteknologi

Biotechnology

Publication and Content Type

vet (subject category)

ovr (subject category)