title: Nanoporous-Gold-Based Electrode Morphology Libraries for Investigating Structure-Property Relationships in Nucleic Acid Based Electrochemical Biosensors.
abstract: Nanoporous gold (np-Au) electrode coatings significantly enhance the performance of electrochemical nucleic acid biosensors because of their three-dimensional nanoscale network, high electrical conductivity, facile surface functionalization, and biocompatibility. Contrary to planar electrodes, the np-Au electrodes also exhibit sensitive detection in the presence of common biofouling media due to their porous structure. However, the pore size of the nanomatrix plays a critical role in dictating the extent of biomolecular capture and transport. Small pores perform better in the case of target detection in complex samples by filtering out the large nonspecific proteins. On the other hand, larger pores increase the accessibility of target nucleic acids in the nanoporous structure, enhancing the detection limits of the sensor at the expense of more interference from biofouling molecules. Here, we report a microfabricated np-Au multiple electrode array that displays a range of electrode morphologies on the same chip for identifying feature sizes that reduce the nonspecific adsorption of proteins but facilitate the permeation of target DNA molecules into the pores. We demonstrate the utility of the electrode morphology library in studying DNA functionalization and target detection in complex biological media with a special emphasis on revealing ranges of electrode morphologies that mutually enhance the limit of detection and biofouling resilience. We expect this technique to assist in the development of high-performance biosensors for point-of-care diagnostics and facilitate studies on the electrode structure-property relationships in potential applications ranging from neural electrodes to catalysts.
authors.affiliation: Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States.
authors.forename: Zimple
authors.initials: Z
authors.lastname: Matharu
authors.affiliation: Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States.
authors.forename: Pallavi
authors.initials: P
authors.lastname: Daggumati
authors.affiliation: Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States.
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States.
authors.forename: Tatiana S
authors.initials: TS
authors.lastname: Dorofeeva
authors.affiliation: Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States.
authors.forename: Zidong
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Electrical and Computer Engineering and ‡Department of Biomedical Engineering, University of California-Davis , Davis, California 95616, United States.
authors.forename: Erkin
authors.identifier: http://orcid.org/0000-0003-2401-3562
authors.initials: E
authors.lastname: Seker
mesh_terms: D015374:Biosensing Techniques; D055664:Electrochemical Techniques; D004566:Electrodes; D006046:Gold; D053768:Metal Nanoparticles; D058608:Nanopores; D009696:Nucleic Acids
chemical_list: D009696:Nucleic Acids; D006046:Gold
keywords: biofouling; electrochemical coarsening; high-throughput material screening; multiple electrode array; nanoporous gold; nucleic acid based biosensors