An Overview on Recent Advances in Biomimetic Sensors for the Detection of Perfluoroalkyl Substances

Abstract

Per- and polyfluoroalkyl substances (PFAS) are a class of materials that have been widely used in the industrial production of a wide range of products. After decades of bioaccumulation in the environment, research has demonstrated that these compounds are toxic and potentially carcinogenic. Therefore, it is essential to map the extent of the problem to be able to remediate it properly in the next few decades. Current state-of-the-art detection platforms, however, are lab based and therefore too expensive and time-consuming for routine screening. Traditional biosensor tests based on, e.g., lateral flow assays may struggle with the low regulatory levels of PFAS (ng/mL), the complexity of environmental matrices and the presence of coexisting chemicals. Therefore, a lot of research effort has been directed towards the development of biomimetic receptors and their implementation into handheld, low-cost sensors. Numerous research groups have developed PFAS sensors based on molecularly imprinted polymers (MIPs), metal–organic frameworks (MOFs) or aptamers. In order to transform these research efforts into tangible devices and implement them into environmental applications, it is necessary to provide an overview of these research efforts. This review aims to provide this overview and critically compare several technologies to each other to provide a recommendation for the direction of future research efforts focused on the development of the next generation of biomimetic PFAS sensors.

Design of a Multiparametric Biosensing Platform and Its Validation in a Study on Spontaneous Cell Detachment from Temperature Gradients

“…Instead of plotting R th , one may also present T 2 as a function of time. 69 Irrespective of the data representation, Figure 3 shows that t d decreases systematically with increasing T 1 , in agreement with earlier observations. 57 Furthermore, we find similar t d values for the two cases with the microbalance function switched on or off.…”

“…R th is hereby a nominal value: it contains a contribution by the thermal resistance of the liquid, being weakly temperature-dependent, and there are parasitic losses of the power P , i.e., a fraction that does not pass the interface. Instead of plotting R th , one may also present T 2 as a function of time . Irrespective of the data representation, Figure shows that t d decreases systematically with increasing T 1 , in agreement with earlier observations .…”