Retention of enzymatic activity of alpha-amylase in the reductive synthesis of gold nanoparticles

In this paper, we report the generation of Au nanoparticles (NPs), using a pure enzyme for the reduction of AuCl4(-), with the retention of enzymatic activity in the complex. As a model system, alpha-amylase was used to readily synthesize and stabilize Au NPs in aqueous solution. Although several ot...

Ausführliche Beschreibung

Bibliographische Detailangaben
Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1992. - 23(2007), 10 vom: 08. Mai, Seite 5700-6
1. Verfasser: Rangnekar, Abhijit (VerfasserIn)
Weitere Verfasser: Sarma, Tridib Kumar, Singh, Atul Kumar, Deka, Jashmini, Ramesh, Aiyagari, Chattopadhyay, Arun
Format: Aufsatz
Sprache:English
Veröffentlicht: 2007
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Chlorides Sulfides Gold 7440-57-5 Deoxyribonuclease EcoRI EC 3.1.21.- alpha-Amylases EC 3.2.1.1
Beschreibung
Zusammenfassung:In this paper, we report the generation of Au nanoparticles (NPs), using a pure enzyme for the reduction of AuCl4(-), with the retention of enzymatic activity in the complex. As a model system, alpha-amylase was used to readily synthesize and stabilize Au NPs in aqueous solution. Although several other enzymes were also pursued for the synthesis, it was interesting to observe that only alpha-amylase and EcoRI could produce Au NPs. Following NP synthesis, the activity of the enzyme was retained in the Au NP-alpha-amylase complex. The presence of Au NPs and alpha-amylase in the complex was established by UV-visible and FT-IR spectroscopy, X-ray diffraction (XRD) and transmission electron microscopic (TEM) measurements. Our observations suggest that the presence of free and exposed S-H groups is essential in the reduction of AuCl4(-) to Au NPs. Structural analysis of the enzymes showed that both alpha-amylase and EcoRI enzymes have free and exposed S-H groups in their native form and thus are suitable for the generation of NPs, whereas the other ones used here do not have such groups. Fortuitously, the enzymatic functional group of alpha-amylase is positioned opposite to that of the free and exposed S-H group, which makes it ideal for the production of Au NPs; binding of the enzyme to Au NPs via Au-S bond and also retention of the biological activity of the enzyme
Beschreibung:Date Completed 27.06.2007
Date Revised 21.11.2008
published: Print-Electronic
Citation Status MEDLINE
ISSN:1520-5827