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| | = Engineered Biology - Microbiology Sensors = |
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| | Sensing Mercury |
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| | '''BBC News: Baby food mercury concern''' April, 2003 |
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| | "A recent analysis of foods found a quarter of samples contained mercury, which on average was double that when baby food was last analysed three years ago. But experts say it is not yet possible to say if these levels are too high." |
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| | [http://news.bbc.co.uk/2/hi/health/2931565.stm Baby food mercury concern] |
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Engineered Biology - Microbiology Sensors
Dunham Lab Chemostat Manual
Masterflex L/S precision variable speed drive
EW-07520-50
each, $850
Masterflex Standard pump head for L/S 13 tubing
EW-07013-20
each, $112
Masterflex PharMed BPT Tubing, L/S #13
EW-06508-13
25'', $67
Does that come with a built-in television?
Engineered Biology - Microbiology Sensors
Dunham Lab Chemostat 'Ministat' Video
Aaron W. Miller, Corrie Befort, Emily O. Kerr, Maitreya J. Dunham
Department of Genome Sciences, University of Washington
"design and operation of a relatively simple, low cost array of miniature chemostats .. in determination of physiology and in evolution experiments with yeast"
JOVE (VIDEO): Design and Use of Multiplexed Chemostat Arrays
Miller, A. W., Befort, C., Kerr, E. O., Dunham, M. J. Design and Use of Multiplexed Chemostat Arrays. J. Vis. Exp. (72), e50262, doi:10.3791/50262 (2013).
Engineered Biology - Microbiology Sensors
Portable LED-array VIS–NIR spectrophotometer/nephelometer
"A portable instrument with a high-speed multiple-wavelength LED array source, and simultaneous detectors for absorbance and 90° nephelometry, was tested from 420 to 950 nm. Absorbance values and simultaneous 90°-scatter intensities at six different wavelengths can be determined and stored every 0.02 s. An advantage of this LED instrument is that its sensitivity is equal to or better than many research-grade spectrophotometers. Also, unlike diode array spectrometers, which emit white light through samples, the LED instrument emits monochromatic light through samples, enabling us to obtain turbidity, turbidity ratio, and particle size information in addition to the absorption spectrum. Field applications can range from simple turbidity and multiple-wavelength absorbance measurements to kinetic experiments with temporal acquisition of multiple-wavelength absorbance and simultaneous turbidity data. Rugged, laptop compatible, portable, and inexpensive, the LED instrument is useful for discrete or on-line VIS–NIR absorption analysis and turbidity, or turbidity ratio, analysis." 1998 John Wiley & Sons, Inc. Field Analyt Chem Technol 2: 21–28, 1998
Engineered Biology - Microbiology Sensors
LED Spectrophotometer
"Hauser et al. [71] employed a fiber optic coupler to guide the light from up to 7 LEDs into a single
measuring cell. This photometer could be configured to detect Al, Cu, NH3, Cu, Ca, chromium,
phosphate and nitrite using colorimetric methods. Acoupler was used to merge the light from one of
the 7 input channels into 2 output fibers. "
"LED as both light source and detector for analytical applications has been developed by Lau et al. The emitter LED is forward biased while the detector LED is reverse biased. ... Additional advantages .. is the size, low power consumption (can operate in microwatts range), can detect low absolute light levels, responds to a broad spectral range (247 to >900 nm) and can achieve good S/N ratio. "
Absorbance Based Light Emitting Diode Optical Sensors and Sensing Devices October 2007, Sensors 2008, 8, 2453-2479
Engineered Biology - Microbiology Sensors
LED Spectrophotometer
"Due to outbreaks such as foot and mouth disease, chicken flu virus and bovine spongiform
encephalopathy (BSE) food safety assurance is of utmost importance. LED based chemical sensors
have also been applied to the monitoring of food products [97, 121, 122]."
"Pacquit et al.employed an LED based detector to monitor fish spoilage [97, 123]. The on package
sensor contains the pH sensitive bromocresol green,which responds through visible change to basic
volatile spoilage compounds such as trimethylamine (TMA), ammonia (NH3) and dimethylamine
(DMA) collectively referred to as Total Volatile Basic Nitrogen (TVB-N). "
"Teshima et al.employed an LED based liquid core waveguide (LCW) absorbance detector for the
measurement of gaseous acetone in human breath. Monitoring breath acetone can be useful to follow
patients on a prescribed diet regimen as well as tomonitor diabetic patients. The detection chemistry
was based on the reaction of acetone with alkaline salicylaldehyde to form a coloured product, which
absorbs in the blue and can be monitored with GaN based LEDs (? max465 nm) [126]. "
Absorbance Based Light Emitting Diode Optical Sensors and Sensing Devices October 2007, Sensors 2008, 8, 2453-2479
Engineered Biology - Microbiology Sensors
Sensing Mercury
"Mercury is also relatively volatile and, therefore, easily lost during sample preparation and analysis. ... Most of the methods available to determine mercury levels in blood, urine, tissues, and hair use atomic absorption spectrometry (AAS), atomic emission spectrometry (AES), atomic fluorescence spectrometry (AFS), neutron activation analysis (NAA), mass spectrometry (MS), or anodic stripping voltametry (ASV). Cold vapour AAS (or CVAAS) is the most widely used."
WHO Guidance for Identifying Populations at Risk from Mercury Exposure August 2008
Engineered Biology - Microbiology Sensors
Sensing Mercury
BBC News: Baby food mercury concern April, 2003
"A recent analysis of foods found a quarter of samples contained mercury, which on average was double that when baby food was last analysed three years ago. But experts say it is not yet possible to say if these levels are too high."
Baby food mercury concern
