title: Synthesis of urease hybrid nanoflowers and their enhanced catalytic properties.
abstract: Increasing numbers of materials have been extensively used as platforms for enzyme immobilization to enhance catalytic activity and stability. Although stability of enzyme was accomplished with immobilization approaches, activity of the most of the enzymes was declined after immobilization. Herein, we synthesize the flower shaped-hybrid nanomaterials called hybrid nanoflower (HNF) consisting of urease enzyme and copper ions (Cu(2+)) and report a mechanistic elucidation of enhancement in both activity and stability of the HNF. We demonstrated how experimental factors influence morphology of the HNF. We proved that the HNF (synthesized from 0.02mgmL(-1) urease in 10mM PBS (pH 7.4) at +4°C) exhibited the highest catalytic activity of ∼2000% and ∼4000% when stored at +4°C and RT, respectively compared to free urease. The highest stability was also achieved by this HNF by maintaining 96.3% and 90.28% of its initial activity within storage of 30 days at +4°C and RT, respectively. This dramatically enhanced activity is attributed to high surface area, nanoscale-entrapped urease and favorable urease conformation of the HNF. The exceptional catalytic activity and stability properties of HNF can be taken advantage of to use it in fields of biomedicine and chemistry.
authors.affiliation: Department of Chemistry, Faculty of Science, Erciyes University, Kayseri 38039, Turkey.
authors.forename: Burcu
authors.initials: B
authors.lastname: Somturk
authors.affiliation: Department of Chemistry, Faculty of Science, Erciyes University, Kayseri 38039, Turkey.
authors.forename: Ismail
authors.initials: I
authors.lastname: Yilmaz
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Erciyes University, 38039 Kayseri, Turkey; Nanotechnology Research Center, Erciyes University, Kayseri 38039, Turkey.
authors.forename: Cevahir
authors.initials: C
authors.lastname: Altinkaynak
authors.affiliation: Department of Chemistry, Faculty of Arts and Science, Nevşehir Hacı Bektaş Veli University, 50300 Nevşehir, Turkey.
authors.forename: Aslıhan
authors.initials: A
authors.lastname: Karatepe
authors.affiliation: Department of Chemistry, Faculty of Science, Erciyes University, Kayseri 38039, Turkey. Electronic address: ozdemirn@erciyes.edu.tr.
authors.forename: Nalan
authors.initials: N
authors.lastname: Özdemir
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Erciyes University, 38039 Kayseri, Turkey; Nanotechnology Research Center, Erciyes University, Kayseri 38039, Turkey. Electronic address: ismailocsoy@erciyes.edu.tr.
authors.forename: Ismail
authors.initials: I
authors.lastname: Ocsoy
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology; D014508:Urea / Q000032:analysis; D014510:Urease / Q000378:metabolism*
chemical_list: D004800:Enzymes, Immobilized; D003300:Copper; D014508:Urea; D014510:Urease
keywords: Copper ions; Enzymatic activity; Flower shape; Hybrid nanomaterials; Urea; Urease