Antibiotic resistance is a topic of major concern because of its widespread existence, representing a serious threat concerning emerging untreatable disease outbreaks. Nevertheless, this problem must be addressed by attacking its roots, namely environmental contamination by pharmaceuticals. For this, low cost in-situ analysis techniques are needed for fast diagnosis and immediate intervention. The main objective of this research proposal is to develop smart-phone based analytical methodologies for in-situ screening of antibiotic contamination in environmental waters. Concentration of target antibiotics from water samples will be performed in solid-phase extraction membranes, followed by evaluation of the amount of retained compounds after addition of a color developing agent or by direct analysis in case of intrinsic fluorescent compounds (such as fluoroquinolones) using image analysis. This methodology is expected to have a low cost (less than one euro, where the major cost is the extracting membrane that can be subdivided for several analysis) in order to be amenable for field implementation using a low sample amount (target volume of 10 mL).
These ideas will be implemented following a research plan designed with contingency features. First, a robust image processing algorithm to quantify analytes based on color will be developed, followed by its application to method implementation based on smart-phones and colorimetry for sulfonamides screening. Having in mind self-fluorescent target analytes, an image processing algorithm to quantify analytes based on fluorescence will be sought, with further application to the development of a smart-phone based screening methodology for fluoroquinolones. Studies concerning real samples and field application of the developed methodologies will be undertaken along the duration of the project. The scientific/technical implementation will be accompanied by dissemination of results in scientific publications, seminar, dedicated website and social networks. At the end of this project, smart-phone applications for evaluation of these two classes of antibiotics will be available for implementation with a validated analytical protocol.
Considering the different skills required for achieving the proposed goals, a multidisciplinary team was assembled. Marcela Segundo (REQUIMTE), PI of this proposal, has an extensive track record on development of analytical methodologies applied to real samples while Helder Oliveira (INESC), co-PI of this proposal, is a young researcher with experience on image analysis, proposing innovative solutions to biomedical applications. Adriano Bordalo-Sá (UP-ICBAS) is an expert in aquatic ecosystems, having a long-standing collaboration with PI on deployment of fast analytical methods for emerging contaminants. Assistance from Salette Reis (U.Porto-FFUP) will be sought for interpretation of physical-chemical properties of target compounds upon retention on the solid-supports.