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Environmental problems - Chemical approaches
RESEARCH ARTICLE

Can r-graphene oxide replace the noble metals in SERS studies: the detection of acrylamide

Elad Segal A and Aharon Gedanken A B C
+ Author Affiliations
- Author Affiliations

A Department of Chemistry, Institute of Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan 52900, Israel.

B National Cheng Kung University, Department of Materials Science and Engineering, Tainan 70101, Taiwan.

C Corresponding author. Email: gedanken@mail.biu.ac.il

Environmental Chemistry 13(1) 58-67 https://doi.org/10.1071/EN14245
Submitted: 19 November 2014  Accepted: 17 April 2015   Published: 14 August 2015

Environmental context. The need for detecting and sensing hazardous materials that can contaminate our food and water is growing each and every year. Regulation of these contaminants to safeguard human health depends on the ability to detect them at ultra-low concentrations in the environment. This work proposes a simple and efficient substrate preparation for detecting acrylamide, a toxic and carcinogenic material usually found in drinking water.

Abstract. Polyacrylamide acts as a very common water purifier worldwide. Unfortunately, it leaves hazardous and toxic residues of its monomer, acrylamide (C3H5NO), in water sources. The World Health Organization (WHO), the Food and Agriculture Organisation of the United Nations (FAO) and the European Union (EU) set the maximum contaminant level of acrylamide in drinking water to 0.1–0.5 µg L–1. This environmental risk encouraged our efforts to develop surface-enhanced Raman spectroscopy (SERS) probes that are easy and simple to fabricate, and also have superb detection ability. We report down to 0.071 µg L–1 acrylamide detection with good reproducibility, which is even lower than the WHO, FAO and EU requirements, and may be used as a powerful analytical alternative for detection. In this manuscript, we present a practical route to fabricate these detection substrates for detection of ultra-low concentrations of aqueous acrylamide solutions. The facile method is based on deposition of graphene oxide on Si wafers by ultrasonication, followed by surface reduction. These substrates require no adhesion layer or pretreatment with O2 plasma or aminopropyl triethoxysilane for the coating process. Sonochemical deposition of silver nanoparticles on the substrates is also carried out and the product compared with the proposed Si–reduced graphene oxide wafers.


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