A Method for Reproducibly Preparing Synthetic Nanopores for Resistive-Pulse Biosensors.
Small (Weinheim an der Bergstrasse, Germany) 2007 Jul 6; 3(8):1424-30
Wharton J JE, Jin P P, Sexton L LT, Horne L LP, Sherrill S SA, Mino W WK,
Department of Chemistry and, Center for Research at the Bio/Nano Interface, University of Florida, G
There is increasing interest in using nanopores in synthetic membranes as resistive-pulse sensors for biomedical analytes. Analytes detected with prototype artificial-nanopore biosensors include drugs, DNA, proteins, and viruses. This field is, however, currently in its infancy. A key question that must be addressed in order for such sensors to progress from an interesting laboratory experiment to practical devices is: Can the artificial-nanopore sensing element be reproducibly prepared? We have been evaluating sensors that employ a conically shaped nanopore prepared by the track-etch method as the sensor element. We describe here a new two-step pore-etching procedure that allows for good reproducibility in nanopore fabrication. In addition, we describe a simple mathematical model that allows us to predict the characteristics of the pore produced given the experimental parameters of the two-step etch. This method and model constitute important steps toward developing practical, real-world, artificial-nanopore biosensors.