title: Gold nanoparticle-assembled capsules and their application as hydrogen peroxide biosensor based on hemoglobin.
abstract: Gold nanoparticle-assembled capsules (GNACs) with controllable size and tunable morphology were fabricated through a simple two-step mixing procedure. Cationic polyelectrolyte was first induced to self-assemble into spherical aggregates in the presence of multivalent anions. Then, the aggregates served as an effective template for the self-assembly of gold nanoparticles to form size-controllable capsules. By adjusting the quantity of gold nanoparticles, capsules with various morphologies could be obtained. Because of their unique nanoporous features, the capsules with intact shells were further used to load hemoglobin (Hb) for the fabrication of a novel H(2)O(2) biosensor. The results of UV-vis spectroscopy and cyclic voltammetry indicated that the capsules provided a suitable matrix for the immobilization of Hb. Additionally, the resulting biosensor showed a high affinity and good catalytic activity to H(2)O(2). With the advantages of the large surface area, good conductivity and biocompatibility, the GNACs can offer a promising platform for the development of biosensors. Moreover, on the basis of the capsule structure, this material may also be expected to apply in some fields such as drug delivery, medical diagnostics and bio-encapsulation.
authors: State Key Lab of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China.
authors: Jie
authors: J
authors: Xuan
authors: Xiang-dong
authors: XD
authors: Jia
authors: Li-Ping
authors: LP
authors: Jiang
authors: E S
authors: ES
authors: Abdel-Halim
authors: Jun-Jie
authors: JJ
authors: Zhu
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D002214:Capsules; D004563:Electrochemistry; D004566:Electrodes; D004579:Electron Transport; D005465:Fluorocarbon Polymers / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D006454:Hemoglobins / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000737:chemistry; D055767:Immobilized Proteins / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D013997:Time Factors
chemical_list: D002214:Capsules; D005465:Fluorocarbon Polymers; D006454:Hemoglobins; D055767:Immobilized Proteins; C040402:perfluorosulfonic acid; D006046:Gold; D006861:Hydrogen Peroxide