Diamond nanowires modified with poly[3-(pyrrolyl)carboxylic acid] for the immobilization of histidine-tagged peptides

Abstract

Coating boron-doped diamond nanowires (BDD NWs) with a conducting polymer, poly[3-(pyrrolyl)carboxylic acid], has been reported. Polymer coating was achieved through electropolymerization of 3-(pyrrolyl)carboxylic acid at the electrode interface by amperometrically biasing the BDD NWs interface until a predefined charge has passed. The poly[3-(pyrrolyl)carboxylic acid] modified BDD NWs (PPA-BDD NWs) were characterized by scanning electron microscopy (SEM) and cyclic voltammetry (CV). Using a deposition charge of 11 mC cm(-2) resulted in a thin polymer film deposition. The availability of the carboxylic groups of the polymer coated BDD NWs electrode was demonstrated through copper ion (Cu(2+)) chelation. The resulting complex was successfully used for the site-specific immobilization of histidine-tagged peptides. The binding process was followed by electrochemical impedance spectroscopy (EIS). The Cu(2+)-chelated PPA-BDD NWs interface showed peptide loading capability comparable to those of commercially available interfaces and can be easily regenerated several times using ethylenediaminetetraacetic acid (EDTA).

Diamond Nanostructures and Nanoparticles: Electrochemical Properties and Applications

“…Furthermore, several diamond nanowires based immunosensors have been reported [33,34,38]. For instance, biotinylated anti-IgG was specifically linked to nickel particles.…”

“…4 Schematic demonstration of a trapping of cytochrome c using diamond nanotextures for an efficient electron transfer process and b the interaction of cytochrome c with the OH-terminated diamond surface [26,30] acid-terminated poly(pyrrole) [38] were applied to construct electrochemical [19], DNA biosensors [35][36][37]39], and immunosensors [32,33,38].…”

Diamond Nanowires: A Novel Platform for Electrochemistry and Matrix-Free Mass Spectrometry

“…The access to such nanostructures allowed finally the use of diamond nanowires for different applications ranging from solid-state electron emitters, high performance nano-electromechanical switches, probes for scanning probe microscopy and photonic systems, to the formation of superhydrophobic and oleophobic interfaces [ 15 , 21 , 26 , 31 , 33 , 37 ] ( Figure 7 ). The use of boron-doped diamond nanowires has in particular found interest for electrochemical sensing [ 10 , 11 , 12 , 25 , 38 , 39 , 40 , 41 , 42 , 43 ] and as surface-assisted laser desorption/ionization (SALDI) matrix [ 27 ].…”

“…Electrochemical immunosensors based on chemically modified BDD NWs electrodes have been lately developed by our group [ 38 , 39 , 40 ]. Diamond nanowires immunosensors were constructed by coating diamond nanowires with functional conducting polymer films (e.g., carboxylic acid-terminated poly(pyrrole), copper ion (Cu 2+ ) chelation followed by linkage of histidine-tagged peptides [ 39 ]) ( Figure 10 A) or by electrochemical deposition of nickel nanoparticles (Ni-NPs) onto diamond nanowires followed by immobilization of biotin-tagged anti-IgG ( Figure 10 B ) [ 38 , 40 ]. Post-coating of diamond nanowires with polymer films can be achieved by amperometrically biasing diamond nanowire electrodes at 1.2 V vs. Ag/AgCl in 3-(pyrrole) carboxylic acid solution [ 39 ].…”

“… Diamond nanowires for immunosensing. ( A ) ( a ) fabrication method of polymer coated BDD NWs (PPA BDD NWs) with chelated Cu 2+ ions and subsequently modified with histidine-terminated target; ( b ) SEM images of BDD NWs after electrochemical deposition of carboxylic acid-terminated poly(pyrrole) (100 mM) in TBATFB (0.1 M)/ acetonitrile solution at E = +1.2 V for different deposition charges (2, 11, 23 mC·cm −2 ) (reprint with permission from [ 39 ]); ( B ) Fabrication method of Ni NPs modified diamond nanowires ( a ), SEM image of Ni NPs modified diamond nanowires ( b ), CV of Ni NPs-BDD NWs in 0.1 M NaOH ( c ), Calibration curve for IgG ( d ) (reprint with permission from [ 40 ]). …”