|Date: August 17, 1998||Environmental Incubator/Shakers|
In this issue of The Scientist, LabConsumer looks at environmental incubator shakers (excluding water-bath-based models), designed to maintain a constant temperature and provide swirling or agitation to flasks, and tubes for a variety of applications. While many of these devices appear to be identical, there are multiple differences among the lot. Here, we'll briefly review a few items to consider when looking for an environmental shaking incubator. Most of these parameters are listed in the accompanying comparative table as well.
Capacity: How much can the shaker hold? Floor-model shakers will generally handle more samples, as well as samples of greater size (for example, 6 liter Erlenmeyer flasks), than their benchtop counterparts. Capacity is generally a function of flask size. There are several benchtop and floor-model units that can be stacked as well, providing added capacity.
Sample Format: Depending on the size of flask, dish, or tube you want agitated, this is an important consideration when it's time to buy. While most units can handle 1 liter Erlenmeyer flasks, few can handle 6 liter flasks. Most companies offer extensive lines of dedicated and/or universal platforms.
Shaking Motion: The majority of the incubator shakers create an orbital (horizontal circular) shaking motion sufficient for mixing liquids in flasks and conducive to culturing cells. Orbital radii differ among units, so it's important to find out if your flask will be gently swirled at a 0.75 inch orbit or whipped about a 3 inch orbit. Agitation rate and orbit size affect aeration and mixing of the culture; greater aeration increases the oxygen transfer rate and boosts cell growth. Brinkmann Instruments provides shakers that offer reciprocal (back-and-forth), rocking (seesaw), and orbital motions.
Temperature Control: The temperature range allowed while shaking is another consideration. Some units come with refrigeration or offer refrigeration as an option. Most of the units are microprocessor controlled, while some of the older or less expensive units have analog controls. Humidity control is also offered on some of the incubators to minimize sample evaporation.
Other Extras: Available with many incubator shakers are gassing manifolds, alarms, chart recorders, cooling coils, platform adapters, and other accessories.
Lighting: Many of the floor-model incubators--and some of the benchtop models--have fluorescent lights or fluorescent light options for photosynthetic studies. Some incubators include Gro-Lux® lamps (GTE Sylvania, Inc.) that optimize plant growth positions by providing a proper balance of light in the red and blue regions. A few incubators have optional UV light banks for sterilization.
Do It Yourself: It should be known that your options are not limited to the choices listed below. Bob Horton has established a web page entitled "Bob Horton's Homemade Shaking Incubator Page." The site describes his design, which incorporates a cardboard box, a record player, particleboard, a thermostat, a 100-watt bulb and socket, a fan and power cord, weather stripping, and other miscellaneous household items.
The design instructions can be viewed at http://biosci.cbs.umn.edu/misc/horton/shaker.html.
The following is a profile of environmental incubator shakers from ten companies.
GYROMAX 727, 737, and 747 Benchtop Incubator Shakers
GYROMAX 737/737R and 747/747R Medium Upright Incubator Shakers
GYROMAX 767/767R and 777/777R Chest-Type Incubator Shakers
GYROMAX 717R and 717RL Large Upright Incubator Shakers
The GYROMAX series of incubator shakers is available in benchtop, medium upright, chest-type, and large upright models. All models are microprocessor controlled and feature a brushless motor and triple eccentric drive for long life and smooth, quiet operation. Also standard within the stainless steel chamber is an adjustable shelf for simultaneous incubation with and without shaking and six 30-Watt fluorescent lamps. The GYROMAX incubator shakers have a temperature range of 5°C above ambient to 80°C, although all units except the benchtop model 727 can be supplied with refrigeration, extending the lower temperature range to 4°C. To save space in the laboratory, two units can be stacked (this includes the 727, 737, 737R, 747, and 747R). The 747 and 747R can accommodate the same number of flasks of a given size as a regular chest type incubator shaker; however, it offers the advantages of a shelf for petri dishes and stackability for increased capacity without additional space requirements.
ATR markets the Infors line of incubator shakers (Infors AG, Switzerland), which have several innovative features. All Infors incubator shakers provide vibration-free shaking and a drain tap for easy removal of any spilled liquids.
The Infors NOVOTRON is a benchtop incubator shaker employing a sophisticated microprocessor for control of shaking and temperature. The speed of the NOVOTRON is adjustable throughout its range of 10 to 400 rpm. The NOVOTRON sports a solid, impact-resistant housing, is easy to clean, and resists abrasion and most chemical solvents.
The new UNITRON is a high capacity incubator shaker with a compact design; the front-opening design allows the unit to fit easily on or under a benchtop, even with refrigeration. The UNITRON has a large inspection window for observation of cultures and a high temperature safety thermostat. Time may be programmed from the front panel via a computer.
The stackable MULTITRON incubator shakers can provide multiple environments for cultures in one place; up to three MULTITRON units can be stacked. The MULTITRON incubators feature dual programming, an inspection light, an adjustable safety thermostat, a cooling system for up to three units, and a large display for speed and temperature.
B. Braun Biotech
BS-1 Incubator Shaker
The BS-1 floor model incubator shaker is controlled by a microprocessor that features a Simple Mode to ensure effortless start-up and a more sophisticated Profile Mode to program all parameters. The shaker is powered by a 1/5 horsepower brushless DC motor with a sealed ball-bearing drive system. The BS-1 has several communication ports, including an RS232 port for a personal computer, a parallel printer port, and two 4-20 mA analog outputs. Other features include automatic restart after power interruption, over-temperature cutoff, a spill ring beneath the shaker platform, and a sealed chamber floor to contain any liquid. Audible/visual alarms are activated when speed or temperature varies outside of run parameters by 5 rpm or 0.5°C, while horizontal airflow within the incubator chamber ensures temperature uniformity. Options on the BS-1 include a 1,000-lumen lighting module, a CFC-free refrigeration module that can cool to 4°C without lights, a support stand, and seismic restraints. Leveling feet, stacking pins, trays, and clamps are also available through B. Braun Biotech.
BioPro International Inc.
Lab-Therm LT-W Table Top Incubator Shakers
ISF-1-W Stackable Incubator Shakers
ISF-4-W Shaker Cabinets
BioPro distributes several incubator shakers for Swiss manufacturer Adolf K¸hner AG. All models have a temperature range of 5°C above ambient to 80°C, while optional refrigerated models can drop the low end to 20°C below ambient. These incubators are microprocessor controlled, offer both orbital and linear shaking motions, and feature soft start and stop--the shaking speed starts and stops slowly to avoid splashing. An optional interface system provides an RS232 port, networking capabilities, a recorder outlet, ISIS software for calibration of parameters, and remote operation via a personal computer. Other standard features include fluorescent lighting, automatic restart after a power failure, automatic stop when the door is opened, and active braking for quick flask or tray changes. The ISF-1-W incubator shakers can be stacked up to three high. The large ISF-4-W offers humidity control, a door heater to prevent condensation on the glass, and both the models offer ISIS software calibration of speed, temperature, and humidity.
Series 1000 Multi Purpose Platform Shakers/Incubators
Though not standard on the Series 1000 Multi Purpose Shakers, the accessory Incubator 1000 (and 1000L) quickly turns the Series 1000 shakers into incubator shakers. These units offer an 11 by 10 inch platform capable of four different motions: orbital, reciprocal, rocking, and 3-D wave mixing; separate models are available for each shaking motion. The platform features a nonskid rubber mat that can accommodate a wide variety of accessories to mix flasks, tubes, bottles, and separatory funnels. Temperature is controlled from 5°C above ambient to 65°C by a two-part transparent hood and a separately controlled heating module. The heating module features an electronic display of set and actual temperatures.
EL605 Benchtop Incubator Shaker
Featuring an internal capacity of 3.9 cubic feet, the EL605 incorporates a microprocessor to control temperature and shaking, while a self- correcting controller compensates instantly for deviations in voltage or workload. The EL605 provides adjustable orbital or reciprocal action from 20 to 230 oscillations per minute with gentle ramping and is monitored within 1 rpm of the set-point by a digital tachometer. A convection fan is used for adjustable temperature inside the incubation chamber; the EL605 has a temperature range from 5°C above ambient to 57°C with a temperature variation of ± 2.5%. The incubator includes a 60-minute timer, rubber feet, and instructions for switching from orbital to reciprocal action.
New 400 Series Incubator Shakers
Model 4520 Incubator Shaker
Model 4535/4536 Incubator Shaker
Model 4580/4581 Incubator/Refrigerator Shaker
Model 4585/4586 Incubator/Refrigerator Shaker
Forma recently introduced the 400 Series incubator shakers that includes three models. The new models 420, 435/436, and 480/481 are similar to the 4520, 4535/4536, and 4580/4.581 incubator shakers, respectively. The new 400 Series incubator shakers feature a new icon-based control panel. This new control panel provides simultaneous display of run-points and set-points.
Excluding the newer 400 series, Forma Scientific offers one benchtop model and three floor-model incubator shakers that utilize a patented orbital shaking mechanism. The 4520 has a temperature range of 5°C above ambient to 80°C, the 4535/4536 models have a range of 5°C above ambient to 60°C, and the refrigerated models can span 4°C to 60°C. Other features of Forma incubator shakers include a 1/3 horsepower brushless motor, Enviro-ScanTM microprocessor control with up to three programmable user-defined protocols, audible/visual rpm and temperature alarms, an RS232 port, and controlled acceleration circuitry for smooth start-up and stopping. A 40-character alphanumeric LCD message screen provides continuous updates of actual process time, RPM, and temperature; set-points and alarm condition messages are also displayed. All console shakers feature key locks to provide product protection and a high efficiency particulate air (HEPA) filter rated at 0.3 µm for entrapment of extraneous airborne particulates. The 4585/4586 models duplicate growing environments through expanded temperature programming and six 30-watt Gro-Lux bulbs.
3527 Bench Top Incubated Shakers
3525 Floor-Model Incubated Shakers
3530 Refrigerated Floor-Model Incubated Shakers
3597 Refrigerated Floor-Model Incubated Shaker
Force Bench Top Incubated Shakers
Force Refrigerated Bench Top Orbital Shakers
Force Digital Floor-Model Incubated Shakers
Force Digital Low-Temperature Incubated Shakers
Lab-Line Thermal Rocker®
Lab-Line manufactures numerous incubator shakers with varying sample capacities in two distinct product categories. The Force series incubators feature microprocessor control, LED displays, and visual and audible alarms when temperature deviates more than 2°C from the set-point. Lab-Line also offers more basic benchtop and floor-model incubator shakers. All Lab-Line units feature orbital shaking and timed operation modes, and the range of programmable temperatures varies among units.
The Force Bench Top Incubated Shakers have a temperature range of 5°C above ambient to 60°C and a nonvolatile memory capable of retaining set-points in case of power interruption, and users can choose from more than 60 platforms for increased versatility. The Force Digital Low-Temperature Incubated Shaker is a high volume floor-model shaker featuring a touch-pad control panel, a 12 by 18 inch viewing window lid, and a temperature range of 5°C to 60° (the Force Digital Floor-Model Incubated Shakers have a temperature range of 5°C above ambient to 60°C). Lab-Line's Force Bench Top Incubated Shakers also have a temperature range of 5°C to 60°, combine microprocessor control with a triple eccentric drive, and have an over-speed safety that stops the shaker if the RPM set-point is exceeded.
Safety features on many of these models include automatic stop when a lid or door is opened, a nonvolatile memory that retains set-points in the event of power interruption and resumes operation when power is restored, and audible and visual alarms. Most incubators feature LED displays, triple eccentric drive mechanisms for smooth, uniform orbital rotation, and lifetime warranties on the drive mechanisms.
Lab-Line's Thermal Rocker is specifically designed for hybridization tasks. Temperature can be set from slightly above ambient to 70°C and rocking speed can be adjusted from 0 to 100 cycles per minute. Users can adjust the angle of rotation on the unit from 10° to 15°.
New Brunswick Scientific
Innova 4000/4080 Benchtop Incubator Shakers
Innova 4200 Benchtop or Floor-Stackable Incubator Shaker
Innova 4230 Benchtop or Floor-Stackable Refrigerated Incubator Shaker
Innova 4300 Incubated Floor-Model Shakers
Innova 4400 Large-Capacity Stackable Shaker
Innova 4900 Multi-Shaker Environmental Chamber
C24 Incubated Benchtop Shaker
C25 Incubated Floor-Model Shakers
Edison, N.J.-based New Brunswick Scientific markets several microprocessor-controlled incubator shakers divided up into two product lines (the Innova series and the more economical C-series incubators). For the benchtop, the C24 generates temperatures from 7°C above ambient to 60°C and features alarms, a timer, and LED display. The Innova benchtop incubators (4000, 4080, and 4230) offer increased capacity without a significant footprint increase, microprocessor intelligence that includes self-correction, set-point retention in a nonvolatile memory, and acceleration control. The Innova 4000 accommodates test tubes and flasks to 2 l and has a temperature range of 5°C above ambient to 60°C, while the high- temperature Innova 4080 goes to 80°C, accommodating hybridization studies. Innova Model 4200 and its refrigerated cousin, Model 4230, are provided with two stationary shelves for incubation or refrigeration of samples and include an electrical receptacle for powering a second shaker or other lab instrumentation, such as a rocker or roller.
The C25 large-capacity incubator shaker, which includes a refrigerated model, can accommodate a variety of interchangeable platforms. The Innova 4300 series comprises four models with varying incubation, refrigeration, illumination, and programming capacities, including models with dual temperature programming and automatic shaking shut-off to limit metabolic activity at the end of a run. A foot pedal assists in ease of use when opening the lid. New Brunswick's Innova 4400 can be stacked three high (two high with refrigeration), features independent speed and temperature controls so different protocols can be carried out, and has a see-through door, and an optional software package allows automated data logging and control. Lastly, the Innova 4900 has a spacious growth chamber, can operate up to four shakers simultaneously, has a temperature range of 20°C below ambient to 60°C, and has self-diagnostic capabilities. Users can choose from lift-out or slide-out platforms for access to flasks. Other features of the Innova 4900 include self-correcting feedback controls, acceleration control, humidity control, light and temperature programming, and a nonvolatile memory.
Sanyo Gallenkamp offers three versions of its Orbital Incubator (Basic, Refrigerated, and Refrigerated Illuminated models). All units feature advanced microprocessor control,over-temperature control, auto-stop and auto-start when the lid is opened and closed, and programming of temperature, orbital speed, and time. The Basic and Refrigerated models also have a double-glazed window for sample viewing. The Basic unit has a temperature range of 5°C above ambient to 60°C, while the Refrigerated unit extends from to 20°C below ambient to 60°C. This unit also features an under-temperature and over-temperature safety thermostat, a delay start to allow temperature set to stabilize for uniformity, and a lockout switch is provided on the side of the unit so program settings cannot be inadvertently changed. The Illuminated Refrigerated model includes six fluorescent lamps built into the lid. These lights are controlled by a variable controller that can be adjusted to provide 20 to 100% light in one percent increments. Also, this unit allows users to program temperature cycles to simulate night and day conditions.
a microplate incubator shaker. A table of microplate incubator/shaker manufactures is available on The Scientist Web site.
The author can be reached online at firstname.lastname@example.org.