Abstract
This paper reports the synthesis and fabrication of aligned electrospun nanofibers derived out of multiwalled carbon nanotubes (MWCNTs) embedded SU-8 photoresist, which are targeted towards ultrasensitive biosensor applications. The ultrasensitivity (detection in the range of fg/mL) and the specificity of these biosensors were achieved by complementing the inherent advantages of MWCNTs such as high surface to volume ratio and excellent electrical and transduction properties with the ease of surface functionalization of SU-8. The electrospinning process was optimized to precisely align nanofibers in between two electrodes of a copper microelectrode array. MWCNTs not only enhance the conductivity of SU-8 nanofibers but also act as transduction elements. In this paper, MWCNTs were embedded way beyond the percolation threshold and the optimum percentage loading of MWCNTs for maximizing the conductivity of nanofibers was figured out experimentally. As a proof of concept, the detection of myoglobin, an important biomarker for on-set of Acute Myocardial Infection (AMI) has been demonstrated by functionalizing the nanofibers with anti-myoglobin antibodies and carrying out detection using a chemiresistive method. This simple and robust device yielded a detection limit of 6 fg/mL.
Highlights
The ever growing demand for ultrasensitive label free biosensors for rapid, early diagnostic applications is being catered to by the rapid advancements in micro- and nanotechnologies that the present decade is witnessing
Phosphate buffered saline tablets (PBS), 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC), N-Hydroxysuccinimide (NHS), chloroform, Bovine Serum Albumin (BSA), Myoglobin from equine skeletal muscle and monoclonal antibody myoglobin purchased from Sigma Aldrich, India
The ultra-sensitivity and the specificity of these biosensors was a result of exploiting the advantages of transduction properties of multiwalled carbon nanotubes (MWCNTs) and the ease of surface functionalization of SU-8 polymer simultaneously
Summary
The ever growing demand for ultrasensitive label free biosensors for rapid, early diagnostic applications is being catered to by the rapid advancements in micro- and nanotechnologies that the present decade is witnessing. Several researchers have explored the platform for the detection of various biomarkers of clinical importance, both in static mode of operation as well as in dynamic mode of operation [2,3,4]. The static mode of operation relies on correlating the amount of steady state deflection of the microcantilever with the concentration of bioanalyte adsorbed onto the cantilever. In the dynamic mode of operation, detection is carried out by monitoring the change in resonance frequency of the cantilever upon the adsorption of bioanalyte. These sensors typically do not have a detection limit below 100 pg/mL. Piezoelectric excited millimeter sized cantilevers (PEMC) have been successfully utilized to achieve a sensitivity of a few femto-gram/mL (fg/mL) [5,6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
