Citation:

Water safety screening via multiplex LAMP-Au-nanoprobe integrated approach, Oliveira, {Beatriz B. }, Veigas Bruno, Carlos {Fábio Ferreira}, Sánchez-Melsió Alexandre, Balcázar {José Luís}, Borrego {Carles M. }, and Baptista {Pedro Viana} , Science of the Total Environment, nov, Volume 741, (2020)

Abstract:

Contaminated water resources remain a major global concern regarding public health. The majority of water safety protocols include indicators of microbial contamination to evaluate the potential risk to public health and are key elements of quality guidelines. Among these, markers for total coliforms and fecal coliforms are strong indicators of co-contamination with other pathogens. Traditional methods, recurring to slow and cumbersome culture-based approaches, have been gradually replaced by molecular methods, capable of faster and more specific screening. These are usually PCR-based methods that may allow for multiple pathogen detection but require dedicated laboratory equipment, hindering the rapid on-site assessment. Here, we used a multiplex Loop-Mediated Isothermal Amplification (mLAMP) strategy for the amplification of two markers associated with the contamination by total and fecal coliforms (e.g. Escherichia coli) — lacZ and uidA genes, respectively — thus allowing for single tube multiplex detection. The mLAMP products were then subject to an Au-nanoprobe colorimetric detection assay for precise discrimination of targets. This approach was validated in 22 water samples that were also screened for the presence of lacZ and uidA using standard and quantitative PCR, with the capability for discriminating the contamination level, e.g. a semi-quantitative evaluation of water quality.

Notes:

This work was financed by FEDER funds through the COMPETE 2020 Program and National Funds through FCT (Portuguese Foundation for Science and Technology) under the projects UlD/Multi/04378/2013 and UID/Multi/04378/2019 for Applied Molecular Biosciences Unit (UCIBIO), SFRH/BPD/124311/2016. JPI Proj No 281715 (TRACE) project. We also acknowledge Sigita Stanynaite for the restriction analysis of lacZ and uidA LAMP products. ICRA researchers acknowledge the support for scientific equipment given by the European Regional Development Fund (FEDER) under the Catalan FEDER Operative Program 2007-2013 and by MINECO according to DA3a of the Catalan Statute of Autonomy and to PGE-2010 as well as the funding from the CERCA program of the Catalan government.