Functional Surfaces for Passive Fungal Proliferation Control: Effect of Surface Micro- and Nanotopography, Material, and Wetting Properties.

Fungal proliferation can lead to adverse effects for human health, due to the production of pathogenic and allergenic toxins and also through the creation of fungal biofilms on sensitive surfaces (i.e., medical equipment). On top of that, food spoilage from fungal activity is a major issue, with food losses exceeding 30% annually. In this study, the effect of the surface micro- and nanotopography, material (aluminum, Al, and poly(methyl methacrylate), PMMA), and wettability against Aspergillus awamori is investigated. The fungal activity is monitored using dynamic conditions by immersing the surfaces inside fungal spore-containing suspensions and measuring the fungal biomass growth, while the surfaces with the optimum antifungal properties are also evaluated by placing them near spore suspensions of A. awamori on agar plates. Al- and PMMA-based superhydrophobic surfaces demonstrate a passive-like antifungal profile, and the fungal growth is significantly reduced (1.6-2.2 times lower biomass). On the other hand, superhydrophilic PMMA surfaces enhance fungal proliferation, resulting in a 2.6 times higher fungal total dry weight. In addition, superhydrophobic surfaces of both materials exhibit antifouling and antiadhesive properties, whereas both superhydrophobic surfaces also create an "inhibition" zone against the growth of A. awamori when tested on agar plates.

Polymeric and Paper-Based Lab-on-a-Chip Devices in Food Safety: A Review.

Food quality and safety are important to protect consumers from foodborne illnesses. Currently, laboratory scale analysis, which takes several days to complete, is the main way to ensure the absence of pathogenic microorganisms in a wide range of food products. However, new methods such as PCR, ELISA, or even accelerated plate culture tests have been proposed for the rapid detection of pathogens. Lab-on-chip (LOC) devices and microfluidics are miniaturized devices that can enable faster, easier, and at the point of interest analysis. Nowadays, methods such as PCR are often coupled with microfluidics, providing new LOC devices that can replace or complement the standard methods by offering highly sensitive, fast, and on-site analysis. This review's objective is to present an overview of recent advances in LOCs used for the identification of the most prevalent foodborne and waterborne pathogens that put consumer health at risk. In particular, the paper is organized as follows: first, we discuss the main fabrication methods of microfluidics as well as the most popular materials used, and then we present recent literature examples for LOCs used for the detection of pathogenic bacteria found in water and other food samples. In the final section, we summarize our findings and also provide our point of view on the challenges and opportunities in the field.