Dark Field Microscopy-Based Biosensors for the Detection of <i>E. coli</i> in Environmental Water Samples
Development of sensitive methods for the determination of <i>E. coli</i> bacteria contamination in water distribution systems is of paramount importance to ensure the microbial safety of drinking water. This work presents a new sensing platform enabling the fast detection of bacteria in...
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| Format: | Article |
| Language: | English |
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MDPI AG
2019-10-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/19/21/4652 |
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| author | Rita La Spina Diana C. António Cloe Desmet Andrea Valsesia Radoslaw Bombera Hedvig Norlén Teresa Lettieri Pascal Colpo |
| author_facet | Rita La Spina Diana C. António Cloe Desmet Andrea Valsesia Radoslaw Bombera Hedvig Norlén Teresa Lettieri Pascal Colpo |
| author_sort | Rita La Spina |
| collection | DOAJ |
| description | Development of sensitive methods for the determination of <i>E. coli</i> bacteria contamination in water distribution systems is of paramount importance to ensure the microbial safety of drinking water. This work presents a new sensing platform enabling the fast detection of bacteria in field samples by using specific antibodies as the biorecognition element and dark field microscopy as the detection technique. The development of the sensing platform was performed using non-pathogenic bacteria, with the <i>E. coli</i> DH5α strain as the target, and <i>Bacillus sp.</i> 9727 as the negative control. The identification of the captured bacteria was made by analyzing the dark field microscopy images and screening the detected objects by using object circularity and size parameters. Specificity tests revealed the low unspecific attachment of either <i>E. coli</i> over human serum albumin antibodies (negative control for antibody specificity) and of <i>Bacillus sp</i>. over <i>E. coli</i> antibodies. The system performance was tested using field samples, collected from a wastewater treatment plant, and compared with two quantification techniques (i.e., Colilert-18 test and quantitative polymerase chain reaction (qPCR)). The results showed comparable quantification capability. Nevertheless, the present method has the advantage of being faster, is easily adaptable to in-field analysis, and can potentially be extended to the detection of other bacterial strains. |
| first_indexed | 2024-04-11T12:09:22Z |
| format | Article |
| id | doaj.art-5712ac8bab7a4bafa75fd0a7c4e9087e |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T12:09:22Z |
| publishDate | 2019-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-5712ac8bab7a4bafa75fd0a7c4e9087e2022-12-22T04:24:38ZengMDPI AGSensors1424-82202019-10-011921465210.3390/s19214652s19214652Dark Field Microscopy-Based Biosensors for the Detection of <i>E. coli</i> in Environmental Water SamplesRita La Spina0Diana C. António1Cloe Desmet2Andrea Valsesia3Radoslaw Bombera4Hedvig Norlén5Teresa Lettieri6Pascal Colpo7European Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, Varese, ItalyEuropean Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, Varese, ItalyEuropean Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, Varese, ItalyEuropean Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, Varese, ItalyEuropean Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, Varese, ItalyEuropean Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, Varese, ItalyEuropean Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, Varese, ItalyEuropean Commission, Joint Research Centre (JRC), Via E. Fermi 2749, 21027 Ispra, Varese, ItalyDevelopment of sensitive methods for the determination of <i>E. coli</i> bacteria contamination in water distribution systems is of paramount importance to ensure the microbial safety of drinking water. This work presents a new sensing platform enabling the fast detection of bacteria in field samples by using specific antibodies as the biorecognition element and dark field microscopy as the detection technique. The development of the sensing platform was performed using non-pathogenic bacteria, with the <i>E. coli</i> DH5α strain as the target, and <i>Bacillus sp.</i> 9727 as the negative control. The identification of the captured bacteria was made by analyzing the dark field microscopy images and screening the detected objects by using object circularity and size parameters. Specificity tests revealed the low unspecific attachment of either <i>E. coli</i> over human serum albumin antibodies (negative control for antibody specificity) and of <i>Bacillus sp</i>. over <i>E. coli</i> antibodies. The system performance was tested using field samples, collected from a wastewater treatment plant, and compared with two quantification techniques (i.e., Colilert-18 test and quantitative polymerase chain reaction (qPCR)). The results showed comparable quantification capability. Nevertheless, the present method has the advantage of being faster, is easily adaptable to in-field analysis, and can potentially be extended to the detection of other bacterial strains.https://www.mdpi.com/1424-8220/19/21/4652bacteria quantificationantibodiesdark field microscopyfield water samples |
| spellingShingle | Rita La Spina Diana C. António Cloe Desmet Andrea Valsesia Radoslaw Bombera Hedvig Norlén Teresa Lettieri Pascal Colpo Dark Field Microscopy-Based Biosensors for the Detection of <i>E. coli</i> in Environmental Water Samples Sensors bacteria quantification antibodies dark field microscopy field water samples |
| title | Dark Field Microscopy-Based Biosensors for the Detection of <i>E. coli</i> in Environmental Water Samples |
| title_full | Dark Field Microscopy-Based Biosensors for the Detection of <i>E. coli</i> in Environmental Water Samples |
| title_fullStr | Dark Field Microscopy-Based Biosensors for the Detection of <i>E. coli</i> in Environmental Water Samples |
| title_full_unstemmed | Dark Field Microscopy-Based Biosensors for the Detection of <i>E. coli</i> in Environmental Water Samples |
| title_short | Dark Field Microscopy-Based Biosensors for the Detection of <i>E. coli</i> in Environmental Water Samples |
| title_sort | dark field microscopy based biosensors for the detection of i e coli i in environmental water samples |
| topic | bacteria quantification antibodies dark field microscopy field water samples |
| url | https://www.mdpi.com/1424-8220/19/21/4652 |
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