Researchers develop cheaper, faster method for acrylamide detection

Fluorescent sensors hold great potential for manufacturers looking to detect acrylamide rapidly in potato chips and cookies on the processing line, researchers say.

Published in the Journal of Biosensors and Bioelectronics, the researchers used fluorescent sensors to detect the potential carcinogen. The method relied on using functional quantum dots – nanocrystals made of semiconductor materials.

“To the best of our knowledge, this is the first time to detect acrylamide in food using a fluorescent sensing method based on functional quantum dots (QDs),” the researchers from Zhejiang University in China wrote.

The method: A breakdown

The researchers used modified QDs that polymerize with the assistance of a photo initiator under UV irradiation. This causes the QDs to become closer together, increasing the intensity of the fluorescent glow.

“The research showed fluorescence intensity increased as the concentration of acrylamide both in aqueous solutions and in food samples increased,” they explained.

QDs have proved successful in many fields including bioanalysis because of their unique photophysical properties, like the high fluorescence quantum yields, size-controlled fluorescence and resistance against photobleaching compared with organic dyes.

Novel detection compared to traditional methods

The standard method for acrylamide detection is chromatography coupled with mass spectrometry and liquid chromatography-mass spectrometry (LC-MS).

However, the researchers said these methods can be costly and require very specific apparatuses and a particular laboratory set-up limiting the use for rapid and on-line acrylamide detection.

The fluorescent sensing method has “great potential for rapid, specific and quantitative on-line detection of acrylamide in thermally processed foods”, they said.

However, they did acknowledge that the method was slightly over-sensitive because L-asparagine triggering signals in the fluorescence sensing which could cause false positive errors during food sample detection. Despite this, they said this could be offset using the enzyme L-asparaginase and added that future research could iron out sensitivity problems.

“Although the sensitivity and specificity cannot be compared with standard LC-MS/MS analysis, this new method requires much less time and cost, which is promising for on-line rapid detection of acrylamide in food processing.”

Source: Journal of Biosensors and Bioelectronics

Published April 2014, Volume 54, Pages 64-71

“Detection of acrylamide in potato chips using a fluorescent sensing method based on acrylamide polymerization-induced distance increase between quantum dots”

Authors: Qinqin Hu, Xiahong Xu, Zhanming Li, Ying Zhang, Jianping Wang, Yingchun Fu and Yanbin Li