In-situ synthesis of 3D ultra-small gold augmented graphene hybrid for highly sensitive electrochemical binding capability

• Published in: Journal of colloid and interface science Vol. 553; pp. 289 - 297
• Main Authors: Taj, Ayesha, Shaheen, Ayesha, Xu, Jie, Estrela, Pedro, Mujahid, Adnan, Asim, Tayyaba, Zubair Iqbal, M., Khan, Waheed S., Bajwa, Sadia Z.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-10-2019
• Subjects: Biomolecules; Cyclic voltammetry; Electrochemical biosensor; Facile growth; Gold nanostructures; Graphene oxide; Hybrid; Cyclic voltammetry; Facile growth; Hybrid; Gold nanostructures; Biomolecules; Graphene oxide; Electrochemical biosensor
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2019.06.013

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•In-situ growth of three-dimensional graphene hybrid is described using Caryota mitis extracts.•Hybrid consisted of ultra -mall gold nanostructures of 2–10 nm homogenously arranged on the graphene sheets.•The hybrid executed both conducting characteristics of graphene sheets and catalytic properties of Au Ns.•The nano-sized morphology constituted sensitive and selective detection platform uric acid.
The fascinating properties of graphene can be augmented with other nanomaterials to generate hybrids to design innovative applications. Contrary to the conventional methodologies, we showed a novel yet simple, in-situ, biological approach which allowed for the effective growth of gold nanostructures on graphene surfaces (3D Au NS@GO). The morphology of the obtained hybrid consisted of sheets of graphene, anchoring uniform dispersion of ultra-small gold nanostructures of about 2–8 nm diameter. Surface plasmon resonance at 380 nm confirmed the nano-regimen of the hybrid. Fourier transform infrared spectroscopy indicated the utilization of amine spacers to host gold ions leading to nucleation and growth. The exceptional positive surface potential of 55 mV suggest that the hybrid as an ideal support for electrocatalysis. Ultimately, the hybrid was found to be an efficient receptor material for electrochemical performance towards the binding of uric acid which is an important biomolecule of human metabolism. The designed material enabled the detection of uric acid concentrations as low as 30 nM. This synthesis strategy is highly suitable to design new hybrid materials with interesting morphology and outstanding properties for the identification of clinically relevant biomolecules.