Improved biosensing of Legionella by integrating filtration and immunomagnetic separation of the bacteria retained in filters

Melania Mesas Gómez, Bárbara Molina-Moya, Bárbara de Araujo Souza, Maria Valnice Boldrin Zanoni, Esther Julián, José Domínguez, Maria Isabel Pividori*

*Corresponding author for this work

Research output: Contribution to journalArticleResearchpeer-review

1 Citation (Scopus)
1 Downloads (Pure)


A novel approach is presented that combines filtration and the direct immunomagnetic separation of the retained bacteria Legionella in filters, for further electrochemical immunosensing. This strategy allows for the separation and preconcentration of the water-borne pathogen from high-volume samples, up to 1000 mL. The limit of detection of the electrochemical immunosensor resulted in 100 CFU mL−1 and improved up to 0.1 CFU mL−1 when the preconcentration strategy was applied in 1 L of sample (103-fold improvement). Remarkably, the immunosensor achieves the limit of detection in less than 2.5 h and simplified the analytical procedure. This represents the lowest concentration reported to date for electrochemical immunosensing of Legionella cells without the need for pre-enrichment or DNA amplification. Furthermore, the study successfully demonstrates the extraction of bacteria retained on different filtering materials using immunomagnetic separation, highlighting the high efficiency of the magnetic particles to pull out the bacteria directly from solid materials. This promising feature expands the applicability of the method beyond water systems for detecting bacteria retained in air filters of air conditioning units by directly performing the immunomagnetic separation in the filters. Graphical abstract: [Figure not available: see fulltext.].

Original languageEnglish
Article number82
Pages (from-to)82
Number of pages13
JournalMicrochimica Acta
Issue number2
Publication statusPublished - Jan 2024


  • Bacteria
  • Biosensing Techniques
  • Immunoassay
  • Immunomagnetic Separation
  • Legionella
  • Water


Dive into the research topics of 'Improved biosensing of Legionella by integrating filtration and immunomagnetic separation of the bacteria retained in filters'. Together they form a unique fingerprint.

Cite this