Packages for Teaching & Research in the Biological Sciences:

Dissolved CO₂ System

Dissolved CO₂ (DCO₂) System are designed to measure dissolved pCO₂ in Water at Atmospheric Pressure. The systems are composed of a DCO₂ Sampler with Accessories, a Non-Dispersive Infrared CO₂ Analyzer with a built-in Gas Pump, Data Interface and Software. The Rapid Response DCO₂ System consists of flow through Rapid DCO₂ Sampling System, Liquid Pump, IRGA with built in Gas Pump, Data Interface and Software.

The DCO₂ Sampler is the key component of the standard system as it samples pCO₂ from the liquid and carries it to the IRGA. The DCO₂ Sampler is covered with PTFE (Polytetrafluoroethylene) Membrane which allows it to be submerged in water (upto 2 ft). The CO₂ Gas Dissolved in Water Diffuses across the PTFE Membrane into the Sampler and is carried to the CO₂ Analyzer in a closed loop fixed volume gas stream for detection. Liquid flow past the sampler is necessary and stirring is required for the system to work well. A Rapid Response DCO₂ System with a flow-through design is also available. It employs the DCO₂ Sampling System where water is circulated through silicone tubules and gas passess on the other side of the tubules in the opposite direction. CO₂ gas then diffuses across the tubules from water to the gas stream and is carried to the CO₂ sensor for measurements.

Note that the response time of the standard system is slow (4-10 min) due to diffusion across the PTFE membrane. The response time depends on the flow of the liquid past the DCO₂ sampler, hence good stirring of the solution is essential. The response time of the flow-through Rapid DCO₂ System is faster 2 to 4 min.

1. Features:
2. Measure Dissolved CO₂ in Fresh and Seawater
3. Customized to Desired pCO₂ Range (ppm to 100%)
4. Based on Diffusion of CO₂ Out of the Liquid
5. Based on Infrared Gas Analysis
6. Insensitive to Carbonates
7. NOT based on pH Measurements

1. Applications:
2. Ocean Acidification Studies
3. Fermentation Studies
4. Algal Cultivation (Bioreactors)
5. Aquaculture
6. Environmental Monitoring
7. Waste Water Management
8. Food and Drink Industry
9. Aquatic Animal Respirometry (Rapid Response System)

1. Components:
2. Included with the Standard DCO₂ System:
1. CO₂ Analyzer with built-in Pump (S157-P for 0-2000ppm range or S158-P for 0-10% Range) (custom ranges also available)
2. dCO₂ Sampler with Accessories (S350) (Tubing, Nafion RH Equilibrator, PTFE Filter, PTFE Sleeve)
3. Flowmeter (F100) for setting the Gas flow through the System
4. Data Acquisition Interface LabQuest Mini (C610)
5. Logger Pro Software C901)
6. Custom Set-up Files (C404)
7. Temperature Sensor (S132)
3. Included with the Rapid Response DCO₂ System:
1. CO₂ Analyzer with built-in Pump (S157-P for 0-2000ppm range or S158-P for 0-10% Range) (custom ranges also available)
2. Rapid DCO₂ Sampling System (S400)
3. Liquid Pump 1LPM (PL175)
4. Flow Meter (F100) for setting the Gas Flow through the System
5. Data Acquisition Interface (C610)
6. Logger Pro Software (C901)
7. Custom Set-up Files (C404)
8. Temperature Sensor (S132)

Optional Sensors such as pH, Salinity, Dissolved O₂ can also be included in the DCO₂ System for monitoring of other parameters that may be complementary to Dissolved CO₂.

1. Software:
1. Sample Data from Standard DCO₂ System:

1. Sample Respirometry Data from Small Gold Fish using Rapid Response DCO₂ System: