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Multi-Pixel Photon Counters for Optofluidic Characterization of Particles and Microalgae.

Asrar P, Sucur M, Hashemi N - Biosensors (Basel) (2015)

Bottom Line: The forward scattering emissions generated by samples passing through the interrogation region were carried through a multimode fiber, located in 135 degree with respect to the excitation fiber, and detected by a MPPC.Larger particles or cells demonstrated larger peak height and width, and consequently larger peak area.Different types of algae were also successfully characterized.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Engineering, Iowa State University, Ames, IA 50011, USA. pouya@gatech.edu.

ABSTRACT
We have developed an optofluidic biosensor to study microscale particles and different species of microalgae. The system is comprised of a microchannel with a set of chevron-shaped grooves. The chevrons allows for hydrodynamic focusing of the core stream in the center using a sheath fluid. The device is equipped with a new generation of highly sensitive photodetectors, multi-pixel photon counter (MPPC), with high gain values and an extremely small footprint. Two different sizes of high intensity fluorescent microspheres and three different species of algae (Chlamydomonas reinhardtii strain 21 gr, Chlamydomonas suppressor, and Chlorella sorokiniana) were studied. The forward scattering emissions generated by samples passing through the interrogation region were carried through a multimode fiber, located in 135 degree with respect to the excitation fiber, and detected by a MPPC. The signal outputs obtained from each sample were collected using a data acquisition system and utilized for further statistical analysis. Larger particles or cells demonstrated larger peak height and width, and consequently larger peak area. The average signal output (integral of the peak) for Chlamydomonas reinhardtii strain 21 gr, Chlamydomonas suppressor, and Chlorella sorokiniana falls between the values found for the 3.2 and 10.2 μm beads. Different types of algae were also successfully characterized.

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Related in: MedlinePlus

A schematic of the microfluidic chip with integrated optics. The laser beam is transferred through a fiber to the interrogation region where the microparticles pass through. An multi-pixel photon counter (MPPC) collects scatted light from the microparticles transferred by the emission fiber. A data acquisition unit collects the analog data from the photodetector and sends it to a desktop computer for further analysis.
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biosensors-05-00308-f001: A schematic of the microfluidic chip with integrated optics. The laser beam is transferred through a fiber to the interrogation region where the microparticles pass through. An multi-pixel photon counter (MPPC) collects scatted light from the microparticles transferred by the emission fiber. A data acquisition unit collects the analog data from the photodetector and sends it to a desktop computer for further analysis.

Mentions: Multimode optical fibers (fiber instrument sales Inc., Oriskany, NY, USA) were utilized as excitation and emission carriers. Fibers were precisely inserted into the channel to excite the samples in a definite wavelength and collect scattered light (Figure 1). The excitation light was provided using a 635 nm red laser. The emission fibers are perpendicular to the excitation fiber and are responsible for carrying the light from microbeads to the photodetection unit of the system. The emission fibers are perfectly mounted in the same plane as the excitation fiber to receive the highest intensity of light emitted from the samples. The MPPC is located in front of emission fibers so it is able collect the emitted light. We used a ceramic MPPC with an effective photosensitive area of 3 × 3 mm2 to detect the forward light scattered from microparticles.


Multi-Pixel Photon Counters for Optofluidic Characterization of Particles and Microalgae.

Asrar P, Sucur M, Hashemi N - Biosensors (Basel) (2015)

A schematic of the microfluidic chip with integrated optics. The laser beam is transferred through a fiber to the interrogation region where the microparticles pass through. An multi-pixel photon counter (MPPC) collects scatted light from the microparticles transferred by the emission fiber. A data acquisition unit collects the analog data from the photodetector and sends it to a desktop computer for further analysis.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4493551&req=5

biosensors-05-00308-f001: A schematic of the microfluidic chip with integrated optics. The laser beam is transferred through a fiber to the interrogation region where the microparticles pass through. An multi-pixel photon counter (MPPC) collects scatted light from the microparticles transferred by the emission fiber. A data acquisition unit collects the analog data from the photodetector and sends it to a desktop computer for further analysis.
Mentions: Multimode optical fibers (fiber instrument sales Inc., Oriskany, NY, USA) were utilized as excitation and emission carriers. Fibers were precisely inserted into the channel to excite the samples in a definite wavelength and collect scattered light (Figure 1). The excitation light was provided using a 635 nm red laser. The emission fibers are perpendicular to the excitation fiber and are responsible for carrying the light from microbeads to the photodetection unit of the system. The emission fibers are perfectly mounted in the same plane as the excitation fiber to receive the highest intensity of light emitted from the samples. The MPPC is located in front of emission fibers so it is able collect the emitted light. We used a ceramic MPPC with an effective photosensitive area of 3 × 3 mm2 to detect the forward light scattered from microparticles.

Bottom Line: The forward scattering emissions generated by samples passing through the interrogation region were carried through a multimode fiber, located in 135 degree with respect to the excitation fiber, and detected by a MPPC.Larger particles or cells demonstrated larger peak height and width, and consequently larger peak area.Different types of algae were also successfully characterized.

View Article: PubMed Central - PubMed

Affiliation: Department of Mechanical Engineering, Iowa State University, Ames, IA 50011, USA. pouya@gatech.edu.

ABSTRACT
We have developed an optofluidic biosensor to study microscale particles and different species of microalgae. The system is comprised of a microchannel with a set of chevron-shaped grooves. The chevrons allows for hydrodynamic focusing of the core stream in the center using a sheath fluid. The device is equipped with a new generation of highly sensitive photodetectors, multi-pixel photon counter (MPPC), with high gain values and an extremely small footprint. Two different sizes of high intensity fluorescent microspheres and three different species of algae (Chlamydomonas reinhardtii strain 21 gr, Chlamydomonas suppressor, and Chlorella sorokiniana) were studied. The forward scattering emissions generated by samples passing through the interrogation region were carried through a multimode fiber, located in 135 degree with respect to the excitation fiber, and detected by a MPPC. The signal outputs obtained from each sample were collected using a data acquisition system and utilized for further statistical analysis. Larger particles or cells demonstrated larger peak height and width, and consequently larger peak area. The average signal output (integral of the peak) for Chlamydomonas reinhardtii strain 21 gr, Chlamydomonas suppressor, and Chlorella sorokiniana falls between the values found for the 3.2 and 10.2 μm beads. Different types of algae were also successfully characterized.

Show MeSH
Related in: MedlinePlus