MCGES – Multichannel Gas Exchange System allows studies of metabolism and physiology of living organisms via measurements of gas exchange. Qubit Systems can provide Gas Exchange Systems customized to your specifications and needs, to study photosynthesis, respiration, transpiration, N2-fixation and other processes.

MCGES-Multichannel Gas Exchange System may be controlled by the C950 Multichannel Gas Exchange Software to measure the flow of gases to the samples, through the sample chambers and to the gas analyzers. The C950 software controls all data acquisition from the sensors and analyzers, graphically displays the data and calculates gas exchange rates as required. Please  Contact QUBIT with your specifications and we will design your gas exchange system.

In a MCGES the reference gas may be supplied to the system from an air pump or from compressed gas tanks or an air compressor. If several gas mixtures are to be used then a gas mixing system is included (G400). Gasses can be humidified and dehumidified using a humidity controller.

In a multichannel system the gas enters the flow controller where it is split between sample channels, the flow in each channel being controlled by needle valves and measured by separate mass flow monitor. Gas Flow Controllers are available for any number of channels in multiples of four (4 (G248), 8 (G245) channels etc).

Gas enters each sample chamber which may or may not be temperature controlled. The structure of the chamber will depend on the organism. At Qubit, we can build chambers to your specifications. The effluent gas from each chamber enters a Gas Switcher (4 channel - G243, 8 channel – G244) that selects one of the channels for analysis, and vents the others to the atmosphere. Alternatively, the gas flow through the non-selected channels may be stopped, sealing that channel.

Gas from the selected channel is analyzed by one or several analyzers that may be arranged in a series or in parallel. Qubit supplies a wide range of analyzers for measuring CO2, O2, water vapor, H2, CH₄, N2O and other gases. Different analyzers are available across a wide range of gas concentrations and offer various features such as on board data acquisitions, rapid response times etc. We also offer gas conditioning columns, such as scrubbers for water and CO2 (A382).

Qubit Systems personnel have been designing gas exchange systems for over 30 years, and have published extensively on the physiology of respiration, photosynthesis and nitrogen fixation. We are committed to providing researchers with the most appropriate gas exchange system for a particular application at the best possible price, and we are always available to provide expert advice freely without obligation.   Contact QUBIT for furhter information.

References:

• M. R. Odiere, K. G. Koski, H. A. Weiler and M. E. Scott. Concurrent nematode infection and pregnancy induce physiological responses that impair linear growth in the murine foetus. Parasitology Vol 137,  p991-1002 (2010).

• Jumbo-Lucioni P, Ayroles JF, Chambers MM, Jorday KW, Leips J, Mackay TFC, DeLuca M. Systems Genetics analysis of body weight and energy metabolism traits in Drosophila melanogaster. BMC Genomics:11 p297- 309 (2010)

The S147 Rapid Response O2/CO2 Analyzer combines both a laser diode O2 sensor and an infrared CO2 detector. This analyzer is designed for measurements of rapid changes in O2 and CO2 such as those occurring  during O2 uptake and CO2 production from breath by breath measurements of human respiration.  Please check Qubit’s BBB1LP Breath by Breath Respirometry Package

The S147 Rapid Response O2/CO2 Analyzer has a built in pump which is set at 400 mL/min to draw samples in through the “Gas In” port located on the front of the analyzer. Gases exit the analyzer from the front panel from the “Exhaust” port. There are controls for calibrating the O2 and CO2 sensors on the front panel including the “Zero” and “Span”. You should only adjust the “Span” for CO2 and O2 if you have calibration gases at hand to perform the calibration. Also located on the front panel of the analyzer are an “On/Off” switch with an indicating LED Light and a pump On/Off” switch with an indicating LED Light. The pump speed control should not need adjustment.

The back panel of the S147 Rapid Response Analyzer contains the power jack (115/220 VAC, 115W), an exhaust port for the fan and an Analog Outputs jack. To this jack you should connect the included data collection cable which connects to a data acquisition system. We recommend the C901 LoggerPro data acquisition software for data collection.

The S147 Rapid Response O2/CO2 Analyzer is supplied with F250 Flow meter and asorted connectors and tubing.

Sample of resting breath O2 and CO2 data:

Specifications:

CO2 sensor:

• Operating Principle:  Infrared Spectroscopy
• CO2 Range:  0-13%
• Accuracy: +/-2 mm Hg @ < 5.0% CO2, < 10% of reading @ > 5.0% CO2
• Operating Temperature:  5o°C to 55°C
• Power Consumption:  335 mW
• Response Time:  Detector: 28 ms , System: 100 ms (typical)
• Breath Rate:  2 – 150 bpm

O2 sensor:

• Operating Principle:  Laser Diode – Optical Absorption
• Range:  5% to 100%
• Resolution:  0.01 Vol.% O2
• Accuracy:  0.1%
• Noise (80 ms average):  0.1%
• Linearity:  0.2 Vol.%
• Drift (2 hrs):  0.1 Vol.%
• Response time (T90):  130 ms @ 200 mL/min flow
• Operating Temperature:  0^oC to 50^oC
• Relative Humidity:  5 to 95%
• Operating Pressure:  25 to 115 kPa

S500 Metabolic Analyzer (Metabox) is the first combined O2 and CO2 analysis system that allows you to take both your lab and your office into the field.  This system is customized to your O2 and CO2 range of analysis.  The system can be provide with only O2 or CO2 analyzer.

The integrated Tough-book hybrid PC provides hours of operation and comes with Qubit’s C950 gas exchange software that may be customized for your specific requirements ( Contact Qubit). View all your data graphically as they are collected, not just a digital display of values, and use whatever additional programs you wish to crunch numbers and prepare reports. The S500 Metabox gives you perfect flexibility and unsurpassed accuracy packaged in a rugged, easy to carry, waterproof case.  Use it in the field (battery pack A247 or A248 optional) or in the lab for your gas exchange measurements.

Features:

• Combined O2 and CO2 Measurements
• Open and Closed System Gas Analysis
• Integrated Gas Pumps
• integrated data acqusition interface
• Integrated Mass Flow Monitors
• Includes Panasonic Tough-book PC
• rugged, waterproof case

Applications:

• Plant photosynthesis and respiration
• Insect Respirometry
• Animal Respirometry
• Soil Respiration
• Atmospheric Monitoring
• Gas Exchange Quotient

S108 Absolute O2 Analyzer is the most flexible, accurate and affordable oxygen analyzer on the market.  It uses a fuel cell sensor that operates at ambient temperature unlike power hungry zirconium sensors that require an on-board furnace.   The sensor incorporates  acid electrolyte and teflon diffusion membrane.  Measurements of pO2 are precise across the entire range from 0% to 100%. For animal and human respirometry, the S108 Absolute O2 Analyzer can be used with our S158 CO2 Analyzer to measure respiratory quotient. For respirometry in smaller or less active organisms, it may be configured in a stop flow or closed gas exchange system. Calibration is easy.  All you need is dry ambient air (use a N2 zero gas for most stringent measurements). Linearity is maintained across the entire dynamic range.  We recommend using S108  with our C950 Gas Exchange Software or other data acquisition software.

Features:

• 0.01% resolution on digital display ­ and much better in software (50ppm)
• Accuracy 0.21% full scale
• Switchable ranges of 0-25% and 0-100% O2 
• Analog output 0-10 V
• response time (90%) 12 sec
• Integrated pressure sensor
• O2 output displayed in % or kPa Pressure pressure output displayed (kPa)
• Optional battery pack for field use
• Built in Temperature compensation
• Weatherproof case

The S108 Oxygen Analyzer is one of the least expensive oxygen analyzers on the market. The fuel cell sensor is easily replaced by the user when necessary (approx. every 2 to 3 years depending on use).

C950 software screen

References:

Soliz J. et al. Erythropoietin regulates hypoxic ventilation in mice by interacting with brainstem and carotid bodies:The Journal of Physiology 568:559-571 (2005)

Because of its huge dynamic range, the S104 DOX can also be used on a lower resolution setting to measure oxygen exchange in larger animals such as rats, rabbits and even pigs.

Qubit Systems’ S104 Differential Oxygen Analyzer (DOX) has the greatest dynamic range of any gas analyzer on the market. In true differential mode it has ranges of ±100, ±300 and ±1000 Pa O2. Both the reference and sample oxygen sensors are monitored independently at the same time. An automated Ref – Sample feature provides measurements of any oxygen difference. By choosing the appropriate range setting, oxygen exchange can be measured with any animal.

Most high resolution gas analyzers require calibration with expensive standard gases, or with elaborate mixing systems to produce these gases. Over the years, calibration costs can far exceed the cost of the analyzer itself. The S104 DOX has an integral calibration system that uses ambient air (simple pressure based calibration).  Calibration is simple, extremely accurate, and perfectly linear over the entire dynamic range of the analyzer and the “cal gas” is freely available.

Features of the S104 DOX include:

• ±1 ppm oxygen resolution against air (that’s 0.0001%!)
• Widest dynamic range of any oxygen analyzer
• Easy calibration without special calibration gases
• Separate analog signals for reference and sample pO2
• Analog signals for differential pO2, absolute pressure, differential pressure, sample and reference cell temperature, instrument temperature

We recommend Qubit’s C950 gas exchange software (optional) for use with the S104 DOX. The software calculates all major respirometry and photosynthesis parameters, and corrects data for variations in environmental conditions.

If you can measure the CO2 exchange of your sample, the DOX allows you to measure real-time O2 exchange in an open flow gas exchange system at the same time. The figure below shows data as recorded by C950 software of CO2 exchange measured with the S157 Co2 analyzer and O2 exchange measured by the S104 in a potato

Specifications:

• Power Supply: 12V 115/220 VAC .
• Oxygen Sensor life: 3 to 5 years.
• Analog Output: 0 to 5 V, Recommend using 16-Bit Analog to Digital converter
• Absolute Signal range: Reference and Sample  0 to 100% O2
• Absolute Signal Resolution: 0.001%O2,
• Absolute Signal Accuracy : +/- 0.002% O2,
• Absolute Signal Response Time: T90 = 20 seconds, Partial Pressure measurement.
• Differential Oxygen Signal Range: 1000 to 10000 ppmO2 (user defined),
• Differential Oxygen Signal Resolution: 1 ppmO2,
• Differential Oxygen Signal Accuracy: +/- 2.5 ppmO2,
• Differential Oxygen Signal Response Time: T90 = 20 seconds, Partial Pressure measurement.
• Absolute Pressure Signal Range: 15 to 115 kPa,
• Absolute Pressure Signal Resolution: 0.01 kPa,
• Absolute Pressure Signal Noise < 0.01 kPa,
• Absolute Pressure Signal Accuracy:  1% of Full Scale.
• Differential Pressure Signal Range: is +/- 620 Pa,
• Differential Pressure Signal Resolution: 1 Pa,
• Differential Pressure Signal Accuracy: 1% of Full Scale.
• Reference and Sample Air Temperature Signals Range: s 0 to 50 C,
• Reference and Sample Air Temperature Signals Resolution: 0.01 C,
• Reference and Sample Air Temperature Signals Accuracy: +/- 0.1 C.
• Oven Temperature Signal Range: 10 to 50 C,
• Oven Temperature Signal Resolution:  0.01 C,
• Oven Temperature Signal Accuracy: +/- 0.1 C.

References

• Willms JR, Dowling AN, Dong ZM, Hunt S, Shelp BJ, Layzell DB The simultaneous measurement of low rates of CO2 and O2 exchange in Biological Systems. Anal. Biochem. 254: 272-282 (1997)
• Willms JR, Salon C, Layzell DB Evidence for light-stimulated fatty acid synthesis in soybean fruit. Plant Physiol. 120: 1117-112 (1999)
• Cen Y-P, Turpin DH, Layzell DB Whole-plant gas exchange and reductive biosynthesis in white lupin. Plant Physiol. 126: 1555-1565 (2001)
• Amthor,JS, Koch GW, Willms JR, Layzell DB  Leaf O2 uptake in the dark is independent of coincident CO2 partial pressure. J.Exp.Bot. 52: 2235-2238 (2001)
• Davey, PA, Hunt S, Hymus GJ, DeLucia EH, Drake BG, Karnosky DF, Long SP Respiratory oxygen uptake is not decreased by an instantaneous elevation of [CO2], but is increased with long term growth in the filed at elevated [CO2]. Plant Physiol. 134: 520-527 (2004) .

• John P. Isanhart, F. M. Anne McNabb and Philip N. Smith. Effects of perchlorate exposure on resting metabolism, peak metabolism, and thyroid function in the prairie vole (Microtus ochrogaster). Environmental Toxicology and Chemistry Vol 24, Issue 3, p678–684 (2005)
• Efrat Elimelech And Berry Pinshow. Variation in food availability influences prey-capture method in antlion larvae. Ecological Entomology Vol 33, Issue 5, p652–662 (2008).

• Leakey ADB, Xu F, Gillespie KM, McGrath JM, Ainsworth EA, Ort DR. Genomic basis for stimulated respiration by plants growing under elevated carbon dioxide. PNAS Vol. 106 Number 9 p3597-3602 (2009)

Qubit Systems’ Q-S102 O2 Analyzer is configured for measuring oxygen concentration in a flow through gas exchange systems in 0-25% or 0-100% range with 0.21% accuracy. The Q-S102 O2 Analyzer is ideal for determining O2 uptake in organisms with high metabolic rates in an open flow system configuration.  For organisms with low metabolic rate it can be used in a closed flow system where the rate of O2 uptake  can be calculated from the slope of O2 decline in the system.

Q-S102  has been developed from the S102 Flow Through O2 Sensor and is a key component of the New Q-Box Packages for both research and teaching.  The following packages include the Q-S102:

Q-Box RP1LP Low Range Respiration Package,

Q-Box RP2LP High Range Respiration Package,

Q-Box NF1LP Nitrogen Fixation Package 

Q-Box HR1LP Human Respirometry Package.

The Q-S102 O2 Analyzer has a galvanic cell (a lead-oxygen battery) consisting of a lead anode, an O2 cathode, and an acid electrolyte.  It also incorporates an O2-permeable Teflon FEP membrane with a gold electrode bonded to its surface.  Oxygen diffusing through this membrane is reduced electrochemically at the gold electrode. A resistor and thermistor (for temperature compensation) are connected between anode and cathode.  The output of the instrument is proportional to the current flowing through the resistor and thermistor and this is proportional to pO2 in contact with Teflon membrane.

Specifications:

Additional Features:

• Simple 2 point calibration
• Output linear over the entire calibration range
• 90% response in twelve seconds
• Span and zero controls
• Output range  0 – 100% = 5V, 0-25% = 5V
• Temperature compensation circuit allows for changes in temperature during measurements without the need to recalibrate
• Expected sensor life is 3 to 5 years.  Qubit offers replacement of the sensor.
• CO2 friendly sensor

References:

• Sadie B. Barr and Jonathan C. Wright. Postprandial energy expenditure in whole-food and processed-food meals: implications for daily energy expenditure. Food Nutr Res. Vol 54 (2010).
• Shannon M. Fernando, Pengcheng Rao, Lee Niel, Diptendu Chatterjee, Marijana Stagljar andD. Ashley Monks. Myocyte Androgen Receptors Increase Metabolic Rate and Improve Body Composition by Reducing Fat Mass. Endocrinology Vol. 151, Number 7, p3125-3132 ( 2010).
• T. Todd Jones, Richard D. Reina, Charles-A. Darveau and Peter L. Lutz. Ontogeny of energetics in leatherback (Dermochelys coriacea) and olive ridley (Lepidochelys olivacea) sea turtle hatchlings. Comparative Biochemistry and Physiology – Part A: Molecular & Integrative Physiology Vol 147, Issue 2, p313-322 (2007).
• R.Refinetti. Absence of circadian and photoperiodic conservation of energy expenditure in three rodent species. Journal Of Comparative Physiology B: Biochemical, Systemic, And Environmental Physiology Vol 177, Number 3, p309-318 (2007).
• Edwin R. Price, Frank V. Paladino, Kingman P. Strohl, Pilar Santidrián T., Kenneth Klann and James R. Spotila. Respiration in neonate sea turtles. Comparative Biochemistry and Physiology, Part A Vol 146, Issue 3, p422–428 (2007).
• David Nestel, Esther Nemny-Lavy, Sheikh Mohammad Islam, Viwat Wornoayporn and Carlos Cáceres. Effects Of Pre-Irradiation Conditioning Of Medfly Pupae (Diptera: Tephritidae): Hypoxia And Quality Of Sterile Males. Florida Entomologist Vol 90 Number 1, p80-87 (2007).
• Muleme HM, Walpole AC and Staples JF. Mitochondrial metabolism in hibernation: metabolic suppression, temperature effects, and substrate preferences. Physiol Biochem Zool. Vol 79, Number 3, p474-83 (2006).
• Tammy Chan and Warren Burggren. Hypoxic incubation creates differential morphological effects during specific developmental critical windows in the embryo of the chicken (Gallus gallus). Respiratory Physiology & Neurobiology Vol 145, Issues 2-3, Pages 251-263 (2005).
• Tapio Eeva, Esa Lehikoinen, and Mikko Nikinmaa. Pollution-Induced Nutritional Stress In Birds: An Experimental Study Of Direct And Indirect Effects. Ecological Applications Vol 13, Issue 5, p1242–1249 (2003).
• Frances D. Duncan and Marcus J. Byrne. Respiratory airflow in a wingless dung beetle. The Journal of Experimental Biology Vol 205, p2489–2497 (2002).
• C. J. Bernacchi,  E. L. Singsaas,  C. Pimentel,  A. R. Portis Jr and S. P. Long. Improved temperature response functions for models of Rubisco-limited photosynthesis. Plant, Cell & Environment Vol 24, Issue 2, p253–259 (2001).

Qubit Systems’ S101 Diffusion Oxygen Sensor is a galvanic cell (a lead-oxygen battery) consisting of a lead anode, an O2 cathode, and an acid electrolyte. It also incorporates an O2-permeable Teflon FEP membrane with a gold electrode bonded to its surface. Oxygen diffusing through this membrane is reduced electrochemically at the gold electrode.

Within the sensor, the following reacti

ons occur:

Cathode: O2 +2H2O + 4e^- = 4OH^-

Anode: 2Pb + 4OH^- = 2PbO + 2H2O + 4e^-

Overall: O2 + 2Pb = 2PbO

A resistor and a thermistor (for temperature compensation) are connected between the anode and the cathode, so that the battery is always discharged. The output of the instrument is proportional to the current flowing through the resistor and thermistor. This is, in turn, proportional to the partial pressure of O2 in contact with the Teflon FEP membrane. The signal from the oxygen sensor is transmitted to the computer via the C410 LabPro data acquisition interface. It is then displayed in “percentage O2” using C901 Logger Pro 3 software.

Additional Features:

• Simple calibration requiring only atmospheric air
• Output linear over the entire calibration range
• 90% response in twelve seconds
• Output controlled by an adjustable gain
• Output range adjustable from 0 – 25% = 5 V to 0 – 100% = 5 V
• Temperature compensation circuit allows for changes in temperature during measurements without the need to recalibrate
• Expected sensor life is 3 to 5 years. Replacements are inexpensive.
• Sensor is fitted with 1/8 inch Nylon NPT Union

If you wish to measure O2 concentration in a flowing gas stream, check our S102 Flow Through Oxygen Sensor.

References:

• Maud Demarty, Julie Bastien, Alain Tremblay, Raymond H. Hesslein and Robert Gill. Greenhouse Gas Emissions from Boreal Reservoirs in Manitoba and Quebec, Canada, Measured with Automated Systems. Environ. Sci. Technol. Vol 43, Number 23, p8908–8915 (2009).

• Joseph Strzalka, Jing Liu, Andrey Tronin, Inna Y. Churbanova, Jonas S. Johansson and J. Kent Blasie. Mechanism of Interaction between the General Anesthetic Halothane and a Model Ion Channel Protein, I: Structural Investigations via X-Ray Reflectivity from Langmuir Monolayers. Biophysical Journal Vol 96, Issue 10, p4164-4175 (2009).

• Stephen Hunt. Measurements of photosynthesis and respiration in plants. Physiologia Plantarum Vol 117, Issue 3, p314–325 (2003).