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Diamond nanowires: a novel platform for electrochemistry and matrix-free mass spectrometry.

Szunerits S, Coffinier Y, Boukherroub R - Sensors (Basel) (2015)

Bottom Line: The unique physicochemical properties of diamond nanowires have generated wide interest for their use as fillers in nanocomposites, as light detectors and emitters, as substrates for nanoelectronic devices, as tips for scanning probe microscopy as well as for sensing applications.In the past few years, studies on boron-doped diamond nanowires (BDD NWs) focused on increasing their electrochemical active surface area to achieve higher sensitivity and selectivity compared to planar diamond interfaces.Then, the potential use of diamond nanowires as inorganic substrates for matrix-free laser desorption/ionization mass spectrometry, a powerful label-free approach for quantification and identification of small compounds, will be discussed.

View Article: PubMed Central - PubMed

Affiliation: Institute of Electronics, Microelectronics and Nanotechnology (IEMN), UMR-CNRS 8520, Université Lille 1, Avenue Poincaré-BP 60069, 59655 Villeneuve d'Ascq, France. sabine.szunerits@iri.univ-lille1.fr.

ABSTRACT
Over the last decades, carbon-based nanostructures have generated a huge interest from both fundamental and technological viewpoints owing to their physicochemical characteristics, markedly different from their corresponding bulk states. Among these nanostructured materials, carbon nanotubes (CNTs), and more recently graphene and its derivatives, hold a central position. The large amount of work devoted to these materials is driven not only by their unique mechanical and electrical properties, but also by the advances made in synthetic methods to produce these materials in large quantities with reasonably controllable morphologies. While much less studied than CNTs and graphene, diamond nanowires, the diamond analogue of CNTs, hold promise for several important applications. Diamond nanowires display several advantages such as chemical inertness, high mechanical strength, high thermal and electrical conductivity, together with proven biocompatibility and existence of various strategies to functionalize their surface. The unique physicochemical properties of diamond nanowires have generated wide interest for their use as fillers in nanocomposites, as light detectors and emitters, as substrates for nanoelectronic devices, as tips for scanning probe microscopy as well as for sensing applications. In the past few years, studies on boron-doped diamond nanowires (BDD NWs) focused on increasing their electrochemical active surface area to achieve higher sensitivity and selectivity compared to planar diamond interfaces. The first part of the present review article will cover the promising applications of BDD NWS for label-free sensing. Then, the potential use of diamond nanowires as inorganic substrates for matrix-free laser desorption/ionization mass spectrometry, a powerful label-free approach for quantification and identification of small compounds, will be discussed.

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Diamond nanowires for immunosensing. (A) (a) fabrication method of polymer coated BDD NWs (PPA BDD NWs) with chelated Cu2+ 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]).
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sensors-15-12573-f010: Diamond nanowires for immunosensing. (A) (a) fabrication method of polymer coated BDD NWs (PPA BDD NWs) with chelated Cu2+ 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]).

Mentions: 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 (Cu2+) chelation followed by linkage of histidine-tagged peptides [39]) (Figure 10A) or by electrochemical deposition of nickel nanoparticles (Ni-NPs) onto diamond nanowires followed by immobilization of biotin-tagged anti-IgG (Figure 10B) [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]. Fine-tuning the charge allowed coating the wires rather than the formation of polymer films (PPA) in solution. Figure 10A shows SEM images of BDD NWs coated with carboxylic acid-terminated polypyrrole (PPA-BDD NWs) by varying the deposition time. At very low deposition charge (2 mC·cm−2), the polymer started to form preferentially at the defect sites of the interface i.e., in-between the BDD NWs. Increasing the deposition charge to 11 mC·cm−2 resulted in polymer coated BDD NWs, while large deposition charges (23 mC·cm−2 and higher) led to a loss of the wire structure in favor of continuous film formation. The available carboxylic groups of the poly(pyrrole) coated wire electrode allows their coordination with copper ion (Cu2+), known to be specific binding sites for His-tagged analytes. Indeed, the affinity constant (KA) of His-Tag-des-Arg6-Bradykinine peptide to Cu2+ coordinated carboxyl-terminated diamond wires was determined as KA = (1.15 ± 0.5) × 106 M−1, higher than that determined in the absence of Cu2+ (KA = (0.31 ± 0.5) × 106 M−1). Concentrations as low as 10 nM resulted in RCT shift of 50 ± 22 Ω on these interfaces, while on a planar BDD interface modified with carboxylic groups and chelated with Cu2+, His-tagged peptide concentrations had to exceed 100 nM to cause a comparable shift.


Diamond nanowires: a novel platform for electrochemistry and matrix-free mass spectrometry.

Szunerits S, Coffinier Y, Boukherroub R - Sensors (Basel) (2015)

Diamond nanowires for immunosensing. (A) (a) fabrication method of polymer coated BDD NWs (PPA BDD NWs) with chelated Cu2+ 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]).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507696&req=5

sensors-15-12573-f010: Diamond nanowires for immunosensing. (A) (a) fabrication method of polymer coated BDD NWs (PPA BDD NWs) with chelated Cu2+ 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]).
Mentions: 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 (Cu2+) chelation followed by linkage of histidine-tagged peptides [39]) (Figure 10A) or by electrochemical deposition of nickel nanoparticles (Ni-NPs) onto diamond nanowires followed by immobilization of biotin-tagged anti-IgG (Figure 10B) [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]. Fine-tuning the charge allowed coating the wires rather than the formation of polymer films (PPA) in solution. Figure 10A shows SEM images of BDD NWs coated with carboxylic acid-terminated polypyrrole (PPA-BDD NWs) by varying the deposition time. At very low deposition charge (2 mC·cm−2), the polymer started to form preferentially at the defect sites of the interface i.e., in-between the BDD NWs. Increasing the deposition charge to 11 mC·cm−2 resulted in polymer coated BDD NWs, while large deposition charges (23 mC·cm−2 and higher) led to a loss of the wire structure in favor of continuous film formation. The available carboxylic groups of the poly(pyrrole) coated wire electrode allows their coordination with copper ion (Cu2+), known to be specific binding sites for His-tagged analytes. Indeed, the affinity constant (KA) of His-Tag-des-Arg6-Bradykinine peptide to Cu2+ coordinated carboxyl-terminated diamond wires was determined as KA = (1.15 ± 0.5) × 106 M−1, higher than that determined in the absence of Cu2+ (KA = (0.31 ± 0.5) × 106 M−1). Concentrations as low as 10 nM resulted in RCT shift of 50 ± 22 Ω on these interfaces, while on a planar BDD interface modified with carboxylic groups and chelated with Cu2+, His-tagged peptide concentrations had to exceed 100 nM to cause a comparable shift.

Bottom Line: The unique physicochemical properties of diamond nanowires have generated wide interest for their use as fillers in nanocomposites, as light detectors and emitters, as substrates for nanoelectronic devices, as tips for scanning probe microscopy as well as for sensing applications.In the past few years, studies on boron-doped diamond nanowires (BDD NWs) focused on increasing their electrochemical active surface area to achieve higher sensitivity and selectivity compared to planar diamond interfaces.Then, the potential use of diamond nanowires as inorganic substrates for matrix-free laser desorption/ionization mass spectrometry, a powerful label-free approach for quantification and identification of small compounds, will be discussed.

View Article: PubMed Central - PubMed

Affiliation: Institute of Electronics, Microelectronics and Nanotechnology (IEMN), UMR-CNRS 8520, Université Lille 1, Avenue Poincaré-BP 60069, 59655 Villeneuve d'Ascq, France. sabine.szunerits@iri.univ-lille1.fr.

ABSTRACT
Over the last decades, carbon-based nanostructures have generated a huge interest from both fundamental and technological viewpoints owing to their physicochemical characteristics, markedly different from their corresponding bulk states. Among these nanostructured materials, carbon nanotubes (CNTs), and more recently graphene and its derivatives, hold a central position. The large amount of work devoted to these materials is driven not only by their unique mechanical and electrical properties, but also by the advances made in synthetic methods to produce these materials in large quantities with reasonably controllable morphologies. While much less studied than CNTs and graphene, diamond nanowires, the diamond analogue of CNTs, hold promise for several important applications. Diamond nanowires display several advantages such as chemical inertness, high mechanical strength, high thermal and electrical conductivity, together with proven biocompatibility and existence of various strategies to functionalize their surface. The unique physicochemical properties of diamond nanowires have generated wide interest for their use as fillers in nanocomposites, as light detectors and emitters, as substrates for nanoelectronic devices, as tips for scanning probe microscopy as well as for sensing applications. In the past few years, studies on boron-doped diamond nanowires (BDD NWs) focused on increasing their electrochemical active surface area to achieve higher sensitivity and selectivity compared to planar diamond interfaces. The first part of the present review article will cover the promising applications of BDD NWS for label-free sensing. Then, the potential use of diamond nanowires as inorganic substrates for matrix-free laser desorption/ionization mass spectrometry, a powerful label-free approach for quantification and identification of small compounds, will be discussed.

Show MeSH