Dual-Functional Peroxidase-Copper Phosphate Hybrid Nanoflowers for Sensitive Detection of Biological Thiols

Abstract

An effective strategy to detect biological thiols (biothiols), including glutathione (GSH), cysteine (Cys), and homocysteine (Hcy), holds significant incentive since they play vital roles in many cellular processes and are closely related to many diseases. Here, we demonstrated that hybrid nanoflowers composed of crystalline copper phosphate and horseradish peroxidase (HRP) served as a functional unit exhibiting dual catalytic activities of biothiol oxidase and HRP, yielding a cascade reaction system for a sensitive one-pot fluorescent detection of biothiols. The nanoflowers were synthesized through the anisotropic growth of copper phosphate petals coordinated with the amine/amide moieties of HRP, by simply incubating HRP and copper(II) sulfate for three days at room temperature. Copper phosphates within the nanoflowers oxidized target biothiols to generate H2O2, which activated the entrapped HRP to oxidize the employed Amplex UltraRed substrate to produce intense fluorescence. Using this strategy, biothiols were selectively and sensitively detected by monitoring the respective fluorescence intensity. This nanoflower-based strategy was also successfully employed for reliable quantification of biothiols present in human serum, demonstrating its great potential for clinical diagnostics.

Bovine Serum Albumin – Hydroxyapatite Nanoflowers as Potential Local Drug Delivery System of Ciprofloxacin

“…After the first report, where copper ions and phosphate buffer were used to form nanoflowers with different proteins, further studies with copper and other ions, including cobalt, calcium, zinc, iron and manganese, were carried out. [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] However, compared to nanoflowers synthesized with copper ions, they are still in the minority. Taking into account the potential applications of hybrid nanoflowers in biomedicine, the usage of nontoxic metal ions must be considered.…”

Acetylcholinesterase–Cu3(PO4)2 hybrid nanoflowers for electrochemical detection of dichlorvos using square-wave voltammetry

“…Mimetic enzymatic activities of the Cu 3 (PO 4 ) 2 backbone ( e.g. , biothiol oxidase mimetic activity 22 ) are also being developed. The application scope of the HNF technique is expanding.…”