“Time may be the fire we burn in.” And though we might not be able to quench its unrelenting flame, scientists have tried to divert its path by isolating small enclosures where time slows to some crawl. Within these chambers the frenetic Brownian dance is a chaperoned waltz, as temperatures approach absolute zero. The interior environment of Cryogenic storage Dewar is a world apart, a reminder from the ultimate heat-death that must befall our universe within the eons into the future.
For many who attempt to discover truths regarding the workings of your cell, holding back the floodgates of energy is a concern of significant proportions. Scientists are generally thinking about very specific cell properties that take place at critical junctions in the lifetime of a cell. Holding these processes away while their properties could be exploited is akin to the trouble of catching one’s shadow.
Cryogenic freezing of cells has been used as you answer to the problem of the slow burn. By reduction of the temperatures of samples towards the glass transition phase of -133°C, the temperature at which all metabolic activity comes to a halt, scientists have the ability to seclude moments over time, returning repeatedly to analyze that instant throughout history.
Unsurprisingly, cryogenics has grown to be an important industry which makes customized products for nearly every conceivable purpose. From small tabletop apparatus to industrial-scale liquifiers, the industry in cryogenics provides mechanical freezers, storage containers, and dewars in every single size, shape, and configuration imaginable. With such a wide variety of products from which to choose expertise in which of them are most effective may elude the standard consumer. In order to provide a review of the most important producers of cryogenic laboratory supplies several manufacturers will likely be profiled in the following paragraphs.
Ultra-low lab freezers are some of those stuff that most people never consider until they quit working. Made to run for a long time without interruption in service, lab freezers will be the quiet sentinels of your laboratory, keeping a vigilant watch across the researcher’s most prized possessions. Most scientists stay away from the idea of what might happen if their freezer failed, or they try to erase the memory through the day if it did. A career’s amount of samples could be lost in one afternoon– several years of careful collecting and cataloging reduced to mere puddles on to the ground. Although this sort of scenario looms ominously from the periphery of every researcher’s consciousness, not many are prepared for the entire day when it actually occurs. Manufacturers of ultra-low lab freezers took great pains to make certain that power failures and refrigerant leaks will never compromise one’s samples. They build machines that usually are meant to be forgotten.
MMR Technologies is the only company which uses the Kleemenko cooling cycle within its refrigerators. Even though the gas industry has used this system for several years, MMR Technologies was the 1st company to patent the technology and adapt it for small, lightweight, and portable freezing systems.
Just how the Kleemenko cycle works is the fact that a mixture of compressed gas and liquid is passed down a countercurrent exchanger and is allowed to expand using a capillary or throttling valve. Cooling occurs upon expansion, along with the cool gas passes support the temperature exchanger, precooling the incoming high-pressure gas. Several liquid-vapor separators might be incorporated from the cycle in order that the expansion of the liquid enables you to precool the vapor (W.A. Little., Presented at ICEC17, Bournemouth, U.K.,July 14-17 1998)
The BIO 120 can be a zero-maintenance, low-power-consumption Kleemenko refrigerator that is ideal for storing frozen tissue, cell cultures, organs, and body parts. The system allows the scientist to warm and cool samples uniformly without shocking them, and because it provides an inside power source it can be used for that transportation of samples from storage facility to research laboratory. Robert Paugh, product manager for MMR Technologies, was insistent on the need for controlled temperature ramping.
“Being a user you want to are aware of the minimum temperature and how it gets there,” said Paugh. MMR Technologies’ enhanced control systems and printed thermal record of cooling makes sure that uniform temperatures have been maintained throughout the cooling process.
Kelvinator Scientific, that is a subsidiary of Frigidaire, provides freezer units for laboratories and pharmacies that are equipped for biological samples at temperatures to -86°C. At temperatures this low animal and plant viruses, bacteria, spores, and bacteriophages can be preserved for longer periods. Locking lids are offered so that you can protect samples from accidental exposure to ambient temperatures. Adjustable shelving, pullout drawers, and drawer partition inserts are useful for separating different experiments.
NuAire, Inc. credits a great deal of its ultralow freezing capabilities to its heavy-gauge galvanized steel cabinets. The heat-conducting quality with this material reduces stress on compressors allowing the units to operate longer and colder than would certainly be possible. Maintaining temperatures at -152°C the NuAire ultralow freezer is capable of holding samples beneath the crystallization point.
In line with the Clean Air Act of 1990 for systems using HCFC/HFC refrigerants, NuAire also relies on a special combination of azeotropic gases which can be non-flammable and permit on-site recycling. Additionally, a built in timer cycles the reduced stage compressor every twenty four hours, turning it well so that the capillary tubing will likely be cleared of ice formation.
So-Low Environmental Equipment Co. carries a long tradition of creating ultralow freezers for laboratory applications. Actually, with four decades of experience under its belt, So-Low is among the oldest manufacturers of ultralow temperature freezers in the business. As soon as the Montreal Protocol started the phase out from CFC refrigerants in 1987, So-Low was among the first to use Dupont Suva 95, the latest CFC-free refrigerant that runs cooler along with less pressure than CFCs. Along with its investigation of eco-friendly refrigerants, So-Low also has developed an innovative compressor which is designed exclusively for its ultralow freezers.
Forma Scientific offers both mechanical and liquid nitrogen storage systems for preserving samples at ultralow temperatures. The mechanical freezers preserve specimens as a result of -86°C, while Forma’s liquid nitrogen freezers store samples at -133°C. Unlike its competitors’ liquid nitrogen freezers, however, Forma provides square cross-section units instead of the typical cylindrical containers. Each one of these cabinets is constructed of cold-rolled steel. Forma’s counterbalanced lids provide easy access, an optional thermal data printer continuously documents all operational functions, as well as a storage system adjusts to accommodate a range of tube sizes. Forma also provides a patented double door unit that separates long term from everyday storage.
Revco is one of the largest manufacturers of laboratory freezers exceeding fifty years of experience in the industry. Revco’s Elite, Value, and Ultima mechanical freezers sustain temperatures from -10°C to only -120°C without CFC refrigerants and can be purchased in chest, upright, and tabletop models. Its sophisticated Ultima freezers offer automatic electronic systems that constantly adjust conditions towards the internal and external environment, correcting for subtle fluctuations in ambient temperature, excessive loading with warm samples, and dirty filters. Additionally, it features a scrubbing cycle that removes vaporized lubricating oil through the evaporating coils.
Sanyo has become manufacturing laboratory and medical freezers for more than 2 decades, starting with its manufacturing of the initial -40°C chest freezer in 1974. Sanyo duplicated this achievement with the introduction of the very first -152°C ultralow temperature freezer in 1991 and additional demonstrated its position by becoming the very first manufacturer to provide a complete range of CFC-free medical freezers. Today, Sanyo offers one of many largest selections of ultralow temperature lab freezers on the market today. Sanyo’s upright and chest freezers are equipped for utilize in preserving cells, bacteria, spores, pollen, sperm, protozoa, and blood components for academic and industrial research.
The expression dewar, originally put on double walled glass vacuum flasks, is already applied to an array of insulated vessels made for upkeep of samples in liquid nitrogen. Based on their size, dewars usually rest on to the ground or sit on tabletops where samples can be easily accessed. Due to the quality of insulation materials, some dewars have maintained critical temperatures so long as 1 year without having to be regenerated with liquid nitrogen. The typical thermal wall is made up of an aluminum or steel sandwich loaded with polyurethane. The shape and configuration of dewars vary to this sort of extent that many companies build custom dewars to buy. Some of these companies in addition to their products are reviewed in the following section.
From Alaskan salmon eggs to embryos from Idaho’s chicken farms, MVE made laboratory freezers for numerous types of applications. Of course, animal breeders are simply a small amount of its customers. Blood and cell storage and also organ shipment are an equally large part of MVE’s business with medical and pharmaceutical applications representing the easiest-growing section of the industry for the company’s products.
MVE was the initial company to build up biological freezers capable of maintaining a -190°C environment to get a full year without refilling with nitrogen. Since that period MVE has released the full collection of XLC series liquid and vapor-phase freezers. The XLC liquid nitrogen freezers are designed for handling as much as 36,000 vials at temperatures as low as -195.8°C. The vapor-phase freezers are designed for cells that may be stored at -125°C but will become damaged or discolored at critical temperatures achieved by liquid nitrogen freezers. The vapor-phase freezers will also be helpful for storing hazardous materials that could cross-communicate inside a liquid medium, including contaminated-blood bags that happen to be liable to break open.
Quantum Technology is actually a worldwide manufacturer and supplier of laboratory freezers with offices in the usa and Germany. Its product line includes everything from compressors and temperature sensors to gas wells and vacuum shrouds.
In accordance with Sean Wolf, product manager for Quantum Technology, one way his company has been able to remain competitive is actually by offering on-site service and warranty repair. Another major selling reason for Quantum’s refrigeration systems is because they may be custom designed.
Among Quantum Technology’s most in-demand products is really a helium recovery system. Although liquid helium is merely $4 or $5 per liter, in lots of countries away from Canada And America and Europe, the expense of purchasing helium is an issue of concern. That is amongst the reasons why Quantum Technology makes a reliable two-stage and three-stage closed-cycle refrigerator wherein the helium is retained from the system. The helium out of this refrigerator is reliquified to use again and again.
Lab-Line Instruments, designer and manufacturer of dewars for scientific research and recently acquired subsidiary of Barnstead Thermolyne, supplies a Thermo-Flask type of products which include wide-mouth flasks, insulated Thermo-Cups, stainless Thermo-Flasks, and enameled steel Thermo-Flasks. Twenty-six different models can be purchased with capacities from 200 cc to 10 liters, and each one of these models can be obtained using a 24-month warranty. Other special features of the Thermo-Flask brand of products include vented lids to avoid pressure build-up, fold-down handles, and borosilicate inner vessels evacuated to supply coolant retention for samples stored in liquid nitrogen or solid CO2.
Barnstead Thermolyne manufactures the Bio-Cane and Locator Plus cryogenic storage systems, which can be distributed by numerous companies throughout america. The Bio-Cane systems can be purchased in five sizes and offer features such as super vacuum insulation, ampule cans, a polycarbonate lid, and color-coded canisters for inventory identification. The Locator Plus storage systems are available in four sizes and also have capacities of up to 6,000 vials. In addition to a few of the standard features present in the Bio-Cane, the Locator provides hanging racks using a gridded box design, audible and visual alarms that warn of low-level conditions, and an ultrasonic liquid level monitor that eliminates connection with liquid nitrogen and consequently reduces evaporation.
Pope Scientific makes a number of traditional dewar flasks in “cylindrical,” “low form shallow,” and “spherical” styles. All Pope dewars are produced from borosilicate glass covered by a protective mesh, and each and every wide-mouth model carries a vented polyethylene stopper to lessen evaporation. Wide-mouth dewars can even be jacketed in aluminum casing for added safety.
Pope Scientific’s narrow-mouth or “constricted-neck” dewars are suited for temporary storage or transfer applications with holding times more than two weeks. Most of these units come equipped with a small-evaporation stopper, a totally shielded evacuation tip, a weighted base, and protective mesh. Choices for these instruments include fiberglass caddies for carrying or decanting.
Taylor-Wharton International makes the K Series, XT (Extended Time), HC (High Capacity), and RS (Rack System) dewars which allow the researcher to save large amounts of semen, embryos, and biological samples at liquid-nitrogen temperatures. All these units is complemented by its unique inventory control system, which was created to maximize the volume of vials that can be safely arranged in a canister-type storage device. By either immersing samples in liquid nitrogen or suspending them in nitrogen vapor, vials could be maintained at temperatures of -196° C.
Cryogenic Tubes are some of the most often used and least considered implements inside the researcher’s tool box. Bags of tubes are stuffed into corners and forgotten until they mysteriously run out 1 day. Then it is time to look shopping. Making decisions about buying cryogenic tubes is normally guided by three primary issues, the very first that concerns the issue of whether they are externally or internally threaded. Advocates of externally threaded vials claim that material is trapped in the threads of internally threaded vials, while proponents from the internally threaded sort reason that externally threaded vials will be more easily contaminated by accidental contact. Although reports have been conducted in an attempt to confirm or refute these claims, these have not been conclusive, along with the debate goes on.
Yet another consideration which comes into mind when selecting cryogenic tubes is the material that these are constructed. While plastic vials are, perhaps, more durable than glass, they take more time to warm which might negatively impact the viability of some cells. Some plastic tubes will also be contaminated with releasing fluids in the molding process. However, releasing fluids can be removed with the good care, and some brands like Axygen are looking at new polished molds which do not require the usage of releasing fluids. Glass, on the other hand, warms rapidly but can also be subject to fracture as a result of microchannels which could form in the glass, causing leakage of sample contents, or even violent explosions. Plastic vials are also susceptible to nitrogen penetration but the opportunity of explosion will not be as great.
Gasketing has been an issue of some contention in this industry. Many cryovials have a washer that keeps the interior pressure in the vial from expelling the tube’s contents after it is warmed to ambient conditions. The rapid expansion of gas within the tube is enough to force cells and fluid through the lids of countless non-gasketed cryotubes. Silicon is normally preferred because the best material for insulating caps against leakage. Although rubber is also used, it features a tendency to lose its elasticity when dropped to freezing temperatures, a problem that was demonstrated if the “O” rings on the space shuttle Challenger failed.
Simport Plastics, headquartered in Quebec, supplies a large variety of cryotubes and microcentrifuge tubes which you can use at temperatures as little as -190°C. Made for handling biological samples under freezing conditions for prolonged periods, its Cryovials™ come provided with attached leak proof caps that contain a dual lip and a silicon washer. A special ridge on each cap makes handling easier, contributing to one-hand aseptic technique, and color-coded cap inserts together with white marking areas make each vial easily identifiable.
Evergreen Scientific manufactures the CryoSure® brand of vials for storing cell cultures, blood/serum specimens, sperm, and other biological fluids at vapor-phase liquid nitrogen temperatures (-195°C). CryoSure vials can be found in 1. ml, 1.5 ml, and three.5 ml sizes and are avalable in round-bottom and freestanding configurations.
Evergreen also has a wide selection of microcentrifuge tubes that range in capacities from 250 µ l to 2. ml. Some examples are polypropylene tubes, which is often used with solvents, alcohols, chlorinated and aromatic hydrocarbons, and ketones. These tubes are sterilized using gamma radiation and they are pressure tested in the vacuum chamber to be sure the longevity of its double-sealing screw caps.
Evergreen has recently designed a new microcentrifuge tube, in cooperation with Washington University Lipid Research Center, for use in lipid fractionation studies. It really is a 1.5 ml polystyrene tube with the 11 mm high-density polyethylene cap. One of the outstanding features of this tube is that it is entirely transparent.
Nalgene® and Nunc™ cryogenic vials include an array of externally and internally threaded vials from 1. to 5. ml capacities which are silicone gasketed and guaranteed to use inside a centrifuge. The Nalgene 5000 series vials feature graduations and therefore are certified being sterile, noncytotoxic and nonpyrogenic, as the System 100 vials are guaranteed to be leakproof in the microcentrifuge as much as 8,000 g and throughout shipment and transport. However, the corporation warns that cryotubes improperly sealed in liquid phase can lead to an explosion or biohazard release. Nalgene and Nunc have given CryoFlex Tubing to avert this contingency.
Wheaton Science Products makes tubes and flasks for almost every eventuality. From serum bottles to mobile phase reservoirs, it offers developed an extensive catalog of items for handling liquid samples. Wheaton’s Cryules® can be bought in both plastic and glass. The glass Cryule is made from Wheaton-33° low extractable glass that can be hermetically sealed. These are typically most suitable to the preservation of biological materials with liquid nitrogen at low temperatures. Wheaton’s plastic Cryules are autoclavable and, like every one of the glass Cryules, can withstand temperatures between -196°C and 121°C. Wheaton Vacules are vials that happen to be constructed for lyophilization and freeze-drying. Their heavy-wall construction ensures they are exceptionally durable, and they can be flame sealed or stored with a range of stoppers and caps.
Corning Incorporated Science Products Division makes some polypropylene vials that are equipped for use at temperatures to -196°C. These come equipped with a number of features including color-coded caps, silicon and rubber washers for secure sealing of contents, and straightforward-to-read graduations for partial volumes. Self-standing and locking features can be purchased with selected styles. All of Corning’s vials are supplied sterile and certified as nonpyrogenic.
Axygen Scientific Inc. makes microcentrifuge and screw-cap tubes for storing samples at subfreezing temperatures which are made with 99.9 percent pure polypropylene with no mineral fillers or chemical toxins. Foreign substances are added limited to the request of the customer, and Axygen’s colorants contain no metallic ions such as iron, chromium, or nickel which can be typical constituents of dyes. Each of the company’s vials is made to snap closed in the locked position for centrifugation, and special piercing ports create the insertion of syringes easier for collecting samples. Axygen’s “O” ring closure system includes a patent-pending alignment system that guarantees how the microtube is aligned within the centrifuge rotor to become re-spun without disturbing the pelletized sediment.
Sarstedt Inc. comes with an extensive catalog of microcentrifuge tubes which are suitable for both freezing at ultralow temperatures and centrifugation which come in a selection of sizes, shapes, and colors. An individual has the choice of choosing from a variety of externally threaded microtubes with attached or enclosed screw caps which might be colored for identification. All Sarstedt’s tubes are sterile, and the polypropylene material from where they can be constructed allows them to endure subfreezing temperatures as well as temperatures and pressures in an autoclave. One of the areas that Sarstedt has paid particular attention to in developing its line of products is the necessity for cryogenic vials that have reaction buffers and enzymes for PCR applications.
Stockwell Scientific manufacturers CRYO-LOK® Cryogenic Vials and screw- cap microcentrifuge tubes for storage and transport at ultralow temperatures. These range in capacity from .5 ml to 3.5 ml and are available in conical and skirted configurations. Stockwell’s microcentrifuge tubes may be put through a centrifugal force of 20,000 g and each one of its O-ring sealed tubes has been sterilized.
Storage inventory systems really are a critical component of any long-term protocol for cryogenic preservation. Once cryogenic vials are stored at subfreezing temperatures they could undergo changes which make them tough to keep trace. Labels can become brittle, breaking and separating from vials, and improperly stored tubes can be dropped into liquid nitrogen making retrieval difficult and costly. One of the most popular techniques for containing samples may be the canister and cane. By using this technique, a number of vials are enclosed in just a long aluminum shaft that may be submerged within liquid nitrogen. The canes can easily be manipulated for small sample volumes and protect vials from damage that could occur from bumping or agitation. For greater storage capacities, however, the drawer technique is usually preferred. Although drawer systems usually expose more samples to warming during exchange, the accessibility from the system reduces exposure a chance to ambient temperatures contributing to less evaporation from your freezer, plus reduces the researcher’s exposure to possibly damaging cryogens.
Forma Scientific makes rack inventory systems for liquid-phase and vapor-phase storage. These racks are meant to optimize the quantity of space for storage afforded by Forma’s liquid nitrogen containers. The regular inventory configuration can be a cardboard or stainless-steel construction arranged into arrowhead or square designs. Vertical inventory systems enable the user to arrange as much as 82 racks at maximum density.
TetraLink International specializes in making storage boxes and rack systems for cryogenic storage. Intended for the widest possible applicability, its freezer storage systems can be bought in a multitude of sizes, shapes, and colors to put nearly every freezer. Clear lids allow contents to become viewed without opening the containers, and they could be adjusted in particular models to fit tubes of varying heights. Round holes provide spacing with clearance for snap-seal and safe-lock caps. TetraLink’s Racksys storage system uses sliding drawers that include storage racks for holding up to 267 microtubes. These drawers may be installed in any upright freezer or refrigerator.
Nalgene and Nunc storage systems comprise a series of plastic or chipboard containers for microcentrifuge tubes and glass vials. These are generally keyed to stop misalignment and give temperature resistance from -196°C to 121°C.
Nalgene® CryoBox Racks provide stainless retainer systems appropriate for all Nalgene and Nunc storage boxes. They feature vertical and horizontal storage for boxes that maintain each box separately for convenient retrieval.
National Labnet provides freezer racks and storage boxes for an increasing variety of sample containers. As high-throughput experiments require greater reserves of reagents, Cryogenic Movable tank has responded with boxes and racks which are constructed for numerous samples of both well plates and cryovials. They have also introduced boxes with telescoping lids as a way to satisfy requirements for single box containers with vials of differing sizes.
Custom Biogenic Systems is probably the largest manufacturers of rack systems for cryogenic storage containers. The truth is, a lot of its products are sold as standard accessories with some of the major producers of laboratory freezers. Its pie-shaped racks are made from steel and will include a selection of cardboard, aluminum, or stainless-steel boxes with 1/2 inch or 5/8″ cell dividers. These systems can be bought as individual units or as complete racks to use in vapor- phase or liquid-phase storage.
Probably, the cryogenic products one buys today could be the same ones that will be used for a long time. Any purchase made today may work for 10 years. Ultimately, researchers buying Cryogenic Centrifugal Pump are not only buying products for their own reasons, they may be buying for their successors. The consumer should think about what might 46dexkpky during the period of years if their samples become degraded or contaminated due to improper storage. A little bit money which was saved at the beginning by scrimping on vials or freezers might not seem like the best trade off when valuable samples are lost. Despite the safeguards built-in to many of these devices many product managers recommend making regular maintenance on these kinds of products a top priority. Appointing a permanent position that accounts for the cryogenic safety of your laboratory’s biological collection is probably the guidelines on how to assure the integrity of those samples.