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Oxycycler GT4181N

Cytocentric® NO Subchamber Controller

  • First NO Gasotransmitter Cell Culture System
  • Precise Automated Exposures of NO
  • Dynamic or Static Exposures
  • Simulate Physiologic and Pathophysiologic conditions
  • Unprecedented NO Induced Phenotypes
  • Keeps Unwanted NO2 Side Product Within Limits
When you publish your data generated with this equipment, please copy and paste as follows for proper citation in your manuscript.

OxyCycler GT4181N Overview


Nitric oxide (NO) is one of the most widely studied cell gasotransmitters, but traditionally has been difficult to work with in cell culture research. Until now the only way to dose NO in cell cultures previously was with a chemical that reacted to produce or “donate” NO. Chemical NO donors are messy and crude. Exposures possible with NO donors are limited. Every attempt is difficult to control and even more difficult to reproduce. Now, with the OxyCycler GT4181N, for the first time, you can precisely and automatically control NO.


Consisting of a GT41 which provides the common O2, CO2, and RH control, and the modular GT81N piggyback controller, which provides the NO, a subchamber culture system controlled by the OxyCycler GT4181N is the most advanced and reliable method for NO culture. Use this NO subchamber cell culture system for any dose and duration programmed, without the hassle and limitations of chemical donors. With the click of a mouse, any exposure can be precisely reproduced using the Oxycycler GT4181N cell culture system. In addition, an unwanted side product that forms from NO and O2 is NO2. This nuisance gas can be prevented from building up in your culture chamber by automated sensing and displacement in real time to limit the concentration of NO2. This is essential for relevant and reproducible results of NO exposures.


The controller is compatible and will fit any standard size C-Chamber. The entire Oxycycler GT4181N cell culture system will fit any existing incubator.



ELECTRICAL POWER: 12 VDC at 6.66A (Power Supply Specifications), Expected current draw around 2.0A. ACCURACY: O2: ±1% at constant temperature/pressure, ±2% over entire temperature range. CO2: ±5% of measurement or 0.1% CO2. Temperature: ±0.6°C. Relative Humidity: ±3% RH between 0-40°C. NO: varies based on calibration for customer protocol

OXYGEN SENSOR: Electro-galvanic fuel cell


NITRIC OXIDE SENSOR: Electro-galvanic fuel cell

NITROGEN DIOXIDE SENSOR: Electro-galvanic fuel cell

GAS SOURCE: Compressed gas tanks, liquid carboys (from headspace) or generators

GAS SUPPLY: Pressurized O2, CO2, N2, O2/CO2 SPAN mix, NO, NO SPAN mix. Customer should consider protocol when ordering SPAN gases. Appropriate CO volume and concentration to be determined by lab safety officer.


GAS CONSUMPTION: Depends on (1) size and leakiness of host chamber, (2) frequency and duration of opening chamber doors and (3) gas level controlled UMBILICAL LENGTH: 12 ft




ALARM OUTPUT: Global Alarm Output and Audible, External Alarm system

ALARM MODES: Process High, Process Low, Deviation High, Deviation Low, Deviation Band

WEIGHT: 22 Lbs


Sensor Operational Parameters

Host Chamber Temperature: 5-40°C Host Chamber Humidity: 15-90%, Non-Condensing





1. Bleed Valves and Barbs: Bleeds gases out of gas supply lines. Calibration cup for sensor attaches here.

2. Controller: Bright blue digits on black back ground. Continuously displays current control gas level, control status, and alarm status in all chambers. Displays menu items and settings during programming.

3. Alarm: Will sound if Ambient gas monitor detects unsafe levels.

4. ZERO Calibration Gas Flowmeter: Used for calibration.

5. SPAN Calibration Gas Flowmeter: Used for calibration.

6. Needle Valves: Sets infusion rate of control gases in each chamber to accommodate different dynamics. Can manually override controller to shut off gas.

7. Accessory Receptacle: 10 Pin Receptacle is for connecting optional accessory units.

8. Communications Cable Jack: This cable relays information for the sensors.

9. Monitor Pod Umbilical: Flexible umbilical connects remote monitor pod to back panel. Semi-swivel connectors at both ends allow 360° orientation. Some models are hard welded; function is the same.

10. Alarm Receptacle: Connect an appropriate alarm to this jack.

11. RS 485 Connections: One cable attaches to a computer and the other cable attaches to another unit, to allow communication with the computer (if applicable).

12. Pump Connection: This 3 pin receptacle supplies power to the Mini Pod Pump.

13. Supply Gas Hose Barb: Barbs for 1/4 inch I.D. hose from gas sources. Handles pressure up to 40 PSIG.

14. Span Mix Barb: Barb for 1/4 inch I.D. hose from gas source.

15. Ground Stud: For grounding the unit to protect from electric damage.

16. Power Receptacle: 12VDC power supply connects here.

17. Monitor Pod Umbilical: Flexible umbilical connects remote monitor pod to back panel. Semi-swivel connectors at both ends allow 360° orientation. Some models are hard welded; function is the same.


Installation Schematic

OxyCycler GT4181N Culture System. Controls dynamic or static O2, CO2, and NO, and limits RH and NO2 in subchamber. Supply gases to GT41 required: Oxygen, Nitrogen, Carbon Dioxide. Calibration gas to GT41 required: certified pre-mix of 10% CO2 in balance oxygen. Supply gases to GT81N: non-certified pre-mix of 1000ppm NO in balance nitrogen.Calibration gases to GT81N required: certified pre-mix of 30ppm NO in balance nitrogen and certified pre-mix 10ppm NO2 in balance nitrogen. oxycyclergt4181n05


The OxyCycler GT4181N is a combination controller consisting of a core GT41 mother controller and the GT81N piggyback controller working in tandem. It makes NO gasotransmitter research easy and reproducible. The core GT41 controls common O2 and CO2 levels in dynamic or static states and limits RH, while the GT81N controls 0-40 ppm NO in dynamic or static exposures, while limiting unwanted NO2 side product from accumulating above critical levels. Optionally, the GT81N can be un-installed from the GT41 and substituted with the GT81C for carbon monoxide culture, or with the GT81CN for both carbon monoxide and nitric oxide culture.


How It Works

Hot swap multipod adapter plate provides microbial barrier filters between cells culturing in the subchamber and all of the sensors and mechanisms that control O2, CO2, RH, NO/NO2 and temperature. Hot swap multipods provide upgrade flexibility and immediate, easy maintenance. A pump draws a sample from the controlled atmosphere, passes by all sensors and returns to chamber through disposable microbial barrier filters. Appropriate gases are infused as necessary by controllers through terminal, microbial barrier filters. Small fan homogenizes gases throughout chamber and can be easily removed, sterilized and replaced. A loop pod (depicted to the far right) keeps a continuous flow of the sample draw in the absence of the CO multipod. If the system is upgraded at a later date, the loop pod is easily removed and replaced with a CO multipod. oxycyclergt4181n06Controller sits outside the incubator and umbilicals extend through port hole on the incubator and connect to Hot Swap Minipod Assembly inside the incubator. oxycyclergt4181n07Operated by a computer and powerful software allows user to program any type of exposure with all variables and repeat those exposures with the click of a mouse. Profiles can be created, stored and recorded 24 hrs a day/7 days a week.


oxycyclergt4181n09Hypoxic stress can model components of many severe diseases such as heart attacks, strokes, asthma, or epilepsy. Frequency, duration and degree of drops are all adjustable. oxycyclergt4181n10Cells destined for implantation will experience hypoxia and may be better prepared if they are conditioned to it before implantation. Ischemia may also be protected by conditioning. The OxyCycler GT4181N can easily run any preconditioning profile. oxycyclergt4181n11Model step reduction in oxygen, similar to altitude acclimation, to gradually condition cells for hypoxic upregulation of gene expression. The rate of change between any two levels is adjustable and repeatable. The duration at any given level is adjustable and repeatable. oxycyclergt4181n12Sudden increases in oxygen can cause cell damage. The OxyCycler GT4181N allows modeling toxicity of oxygen in any cell culture, similar to toxicity from recreational oxygen inhalation by athletes, therapeutic oxygen administration in critical care units, and other sudden exposures to high oxygen. The rate of oxygen increase can be adjusted to change faster to overwhelm antioxidants, or change slower to condition for antioxidants.