Feasibility study on enhancing the bio-sensors detective limitation of anionic surfactants

Author: Jinjian Wu

Wu, Jinjian, 2018 Feasibility study on enhancing the bio-sensors detective limitation of anionic surfactants, Flinders University, College of Science and Engineering

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Abstract

The perfluoroalkyl substances (PFASs) are a kind of fluorinated organic chemicals which were firstly synthesised in the 1950s. Due to their unique chemical and physical properties, they have been chosen for several purposes, such as firefighting form and non-stick coating. Their worldwide commercial uptake has dramatically increased its usage in the past 70 years, drawing researcher’s attention towards different aspects of PFASs such as their manufacturing method, analysis method, applications, but most importantly, the health effects of PFASs in water systems. The results of many studies show strong relationships between the level of PFASs and several serious illnesses including cancers of different types. Therefore, the US environment protection agency (EPA) had decreased the detected content level of PFASs in the drinking water several times to 0.07 ppb to prevent more illnesses from being developed. Other developed countries such as Germany and France have followed the US’s action to reduce the level of PFASs in the drinking water, at the same time, it is believed that Australia will plan to revise the related acts.

Facing this urgent and indeed need, high-performance liquid chromatography (HPLC) is still the golden standard for detecting the PFASs in the water, but the disadvantage of using the HPLC is its requirement of a well-trained operator, time-consuming process, huge size and high cost limit its application from being implemented from onsite occasions. The astkCARE kit was a portable device which was invented to detect the concentration of PFOS/ PFOA in water by driving the patented reagent and capturing a picture through a smartphone’s camera. The advantage of astkCARE is in its portability and acceptable accuracy, but the detection limit of astkCARE kit still does not extend to the requirement of US EPA, and thus there is potential to further optimize the size and structure of the astkCARE kit.

In this thesis, the existing bio-sensor device is optimised with (1) the VFD (vortex fluidic technologies) technology to increase the effectiveness of extraction process during the sample pre-treatment, (2) introducing the fluorescence detection method. With those optimisations, the preliminary results are very promising with enhanced anionic surfactants detection sensitivity. Further works will focus on the miniaturization of the device without additional power and the autonomous real-time measurement.

Keywords: PFOS/ PFOA, vortex fluidic technologies(VFD), extraction efficiency, astkCARE

Subject: Engineering thesis

Thesis type: Masters
Completed: 2018
School: College of Science and Engineering
Supervisor: Associate Professor Youhong Tang