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Lab-on-a-chip pathogen sensors for food safety.

Yoon JY, Kim B - Sensors (Basel) (2012)

Bottom Line: Several different types of lab-on-a-chip biosensors, including immunoassay- and PCR-based, have been developed and tested for detecting foodborne pathogens.Their assay performance, including detection limit and assay time, are also summarized.Finally, the use of optical fibers or optical waveguide is discussed as a means to improve the portability and sensitivity of lab-on-a-chip pathogen sensors.

View Article: PubMed Central - PubMed

Affiliation: Department of Agricultural and Biosystems Engineering, the University of Arizona, Tucson, AZ 85721, USA. jyyoon@email.arizona.edu

ABSTRACT
There have been a number of cases of foodborne illness among humans that are caused by pathogens such as Escherichia coli O157:H7, Salmonella typhimurium, etc. The current practices to detect such pathogenic agents are cell culturing, immunoassays, or polymerase chain reactions (PCRs). These methods are essentially laboratory-based methods that are not at all real-time and thus unavailable for early-monitoring of such pathogens. They are also very difficult to implement in the field. Lab-on-a-chip biosensors, however, have a strong potential to be used in the field since they can be miniaturized and automated; they are also potentially fast and very sensitive. These lab-on-a-chip biosensors can detect pathogens in farms, packaging/processing facilities, delivery/distribution systems, and at the consumer level. There are still several issues to be resolved before applying these lab-on-a-chip sensors to field applications, including the pre-treatment of a sample, proper storage of reagents, full integration into a battery-powered system, and demonstration of very high sensitivity, which are addressed in this review article. Several different types of lab-on-a-chip biosensors, including immunoassay- and PCR-based, have been developed and tested for detecting foodborne pathogens. Their assay performance, including detection limit and assay time, are also summarized. Finally, the use of optical fibers or optical waveguide is discussed as a means to improve the portability and sensitivity of lab-on-a-chip pathogen sensors.

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Related in: MedlinePlus

The lab-on-a-chip with optical waveguide channels to irradiate the main microfluidic channel and detect light scattering from it. Silicone oil within the optical waveguide channel acts as a core and the surrounding polydimethyl siloxane (PDMS) lab-on-a-chip acts as a cladding of an optical fiber. Reprinted from [107] with permission © SPIE.
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f16-sensors-12-10713: The lab-on-a-chip with optical waveguide channels to irradiate the main microfluidic channel and detect light scattering from it. Silicone oil within the optical waveguide channel acts as a core and the surrounding polydimethyl siloxane (PDMS) lab-on-a-chip acts as a cladding of an optical fiber. Reprinted from [107] with permission © SPIE.

Mentions: Addition of a planar optical waveguide with a liquid core (to replace fiber insertion) overcomes these challenges, creating a simple method of both fabrication/assembly and operation. Biosensors (but not lab-on-a-chip devices) based on planar optical waveguides has provided versatile and robust transduction sensor platforms for the rapid and sensitive analysis of complex environmental and medical samples, with facile integration with sample delivery and detection systems [104]. A handful of techniques have recently been investigated for integrating optical waveguides onto lab-on-a-chip devices, including integrated microfluidic planar optical waveguide system for measuring light scattered from a single scatterer [105], and liquid core optical waveguides for DNA fragment analysis [106]. Integrated optical waveguides have not been investigated previously for use in realistic biological assays, especially general immunoassays or latex agglutination tests. However, the technology is a good fit for the application, as it allows for precise positioning of the light source and detector at a very close proximity to the detection area of the chip, which eliminates the need for larger and expensive optical positioning stages. Angus et al. [107] recently demonstrated the use of such integrated optical waveguides in lab-on-a-chip for detection of Cryptosporidium from various field water samples (Figure 16).


Lab-on-a-chip pathogen sensors for food safety.

Yoon JY, Kim B - Sensors (Basel) (2012)

The lab-on-a-chip with optical waveguide channels to irradiate the main microfluidic channel and detect light scattering from it. Silicone oil within the optical waveguide channel acts as a core and the surrounding polydimethyl siloxane (PDMS) lab-on-a-chip acts as a cladding of an optical fiber. Reprinted from [107] with permission © SPIE.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472853&req=5

f16-sensors-12-10713: The lab-on-a-chip with optical waveguide channels to irradiate the main microfluidic channel and detect light scattering from it. Silicone oil within the optical waveguide channel acts as a core and the surrounding polydimethyl siloxane (PDMS) lab-on-a-chip acts as a cladding of an optical fiber. Reprinted from [107] with permission © SPIE.
Mentions: Addition of a planar optical waveguide with a liquid core (to replace fiber insertion) overcomes these challenges, creating a simple method of both fabrication/assembly and operation. Biosensors (but not lab-on-a-chip devices) based on planar optical waveguides has provided versatile and robust transduction sensor platforms for the rapid and sensitive analysis of complex environmental and medical samples, with facile integration with sample delivery and detection systems [104]. A handful of techniques have recently been investigated for integrating optical waveguides onto lab-on-a-chip devices, including integrated microfluidic planar optical waveguide system for measuring light scattered from a single scatterer [105], and liquid core optical waveguides for DNA fragment analysis [106]. Integrated optical waveguides have not been investigated previously for use in realistic biological assays, especially general immunoassays or latex agglutination tests. However, the technology is a good fit for the application, as it allows for precise positioning of the light source and detector at a very close proximity to the detection area of the chip, which eliminates the need for larger and expensive optical positioning stages. Angus et al. [107] recently demonstrated the use of such integrated optical waveguides in lab-on-a-chip for detection of Cryptosporidium from various field water samples (Figure 16).

Bottom Line: Several different types of lab-on-a-chip biosensors, including immunoassay- and PCR-based, have been developed and tested for detecting foodborne pathogens.Their assay performance, including detection limit and assay time, are also summarized.Finally, the use of optical fibers or optical waveguide is discussed as a means to improve the portability and sensitivity of lab-on-a-chip pathogen sensors.

View Article: PubMed Central - PubMed

Affiliation: Department of Agricultural and Biosystems Engineering, the University of Arizona, Tucson, AZ 85721, USA. jyyoon@email.arizona.edu

ABSTRACT
There have been a number of cases of foodborne illness among humans that are caused by pathogens such as Escherichia coli O157:H7, Salmonella typhimurium, etc. The current practices to detect such pathogenic agents are cell culturing, immunoassays, or polymerase chain reactions (PCRs). These methods are essentially laboratory-based methods that are not at all real-time and thus unavailable for early-monitoring of such pathogens. They are also very difficult to implement in the field. Lab-on-a-chip biosensors, however, have a strong potential to be used in the field since they can be miniaturized and automated; they are also potentially fast and very sensitive. These lab-on-a-chip biosensors can detect pathogens in farms, packaging/processing facilities, delivery/distribution systems, and at the consumer level. There are still several issues to be resolved before applying these lab-on-a-chip sensors to field applications, including the pre-treatment of a sample, proper storage of reagents, full integration into a battery-powered system, and demonstration of very high sensitivity, which are addressed in this review article. Several different types of lab-on-a-chip biosensors, including immunoassay- and PCR-based, have been developed and tested for detecting foodborne pathogens. Their assay performance, including detection limit and assay time, are also summarized. Finally, the use of optical fibers or optical waveguide is discussed as a means to improve the portability and sensitivity of lab-on-a-chip pathogen sensors.

Show MeSH
Related in: MedlinePlus