“Time will be the fire we burn in.” And even though we may not be able to quench its unrelenting flame, scientists have attempted to divert its path by isolating small enclosures where time slows to a crawl. Within these chambers the frenetic Brownian dance turns into a chaperoned waltz, as temperatures approach absolute zero. The inner environment of Air separation equipment is actually a world apart, a reminder in the ultimate heat-death that has to befall our universe inside the eons to come.
For individuals who attempt to discover truths about the workings in the cell, holding back the floodgates of your energy is an issue of significant proportions. Scientists tend to be interested in very specific cell properties that occur at critical junctions within the lifetime of a cell. Holding these processes away while their properties could be exploited is similar to the situation of catching one’s shadow.
Cryogenic freezing of cells has been used as one solution to the trouble of the slow burn. By reducing the temperatures of samples towards the glass transition phase of -133°C, the temperature where all metabolic activity concerns a halt, scientists can seclude moments in time, returning time and again to investigate that instant throughout history.
Unsurprisingly, cryogenics has grown to be an important industry that makes customized products for almost every conceivable purpose. From small tabletop apparatus to industrial-scale liquifiers, the market in cryogenics provides mechanical freezers, canisters, and dewars in every size, shape, and configuration imaginable. With such numerous types of products to pick from knowledge of which ones are best may elude the standard consumer. As a way to provide an overview of the major producers of cryogenic laboratory supplies several manufacturers will be profiled in this article.
Ultra-low lab freezers are among those things which most people never take into consideration until they quit working. Designed to run for a long time without interruption in service, lab freezers are the quiet sentinels from the laboratory, keeping a vigilant watch over the researcher’s most prized possessions. Most scientists stay away from thinking about what might happen if their freezer failed, or they try to erase the memory through the day when it did. A career’s worth of samples can be lost in a single afternoon– many years of careful collecting and cataloging reduced to mere puddles on the ground. Despite the fact that this type of scenario looms ominously inside the periphery of each and every researcher’s consciousness, not many are prepared for the entire day in the event it actually occurs. Manufacturers of ultra-low lab freezers took great pains to make sure that power failures and refrigerant leaks will never compromise one’s samples. They build machines that usually are meant to be forgotten.
MMR Technologies will be the only company that utilizes the Kleemenko cooling cycle within its refrigerators. Even though the natural gas industry has utilized this procedure for several years, MMR Technologies was the initial company to patent the technology and adapt it for small, lightweight, and portable freezing systems.
Just how the Kleemenko cycle works is that an assortment of compressed gas and liquid is passed down a countercurrent exchanger which is allowed to expand using a capillary or throttling valve. Cooling occurs upon expansion, and the cool gas passes backup the heat exchanger, precooling the incoming high-pressure gas. A number of liquid-vapor separators could be incorporated inside the cycle to ensure the expansion of the liquid can be used to precool the vapor (W.A. Little., Presented at ICEC17, Bournemouth, U.K.,July 14-17 1998)
The BIO 120 is really a zero-maintenance, low-power-consumption Kleemenko refrigerator that is ideal for storing frozen tissue, cell cultures, organs, and the body parts. The machine allows the scientist to warm and cool samples uniformly without shocking them, and also since it provides an internal power source you can use it to the transportation of samples from storage facility to look into laboratory. Robert Paugh, product manager for MMR Technologies, was insistent on the requirement for controlled temperature ramping.
“Like a user you wish to understand the minimum temperature and the way it gets there,” said Paugh. MMR Technologies’ enhanced control systems and printed thermal record of cooling ensures that uniform temperatures have been maintained through the cooling process.
Kelvinator Scientific, which is a subsidiary of Frigidaire, provides freezer units for laboratories and pharmacies that are designed for biological samples at temperatures to -86°C. At temperatures this low animal and plant viruses, bacteria, spores, and bacteriophages could be preserved for longer periods. Locking lids are provided as a way to 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 much of its ultralow freezing capabilities to its heavy-gauge galvanized steel cabinets. The temperature-conducting quality with this material reduces stress on compressors allowing the units to operate longer and colder than would otherwise be possible. Maintaining temperatures at -152°C the NuAire ultralow freezer can do holding samples beneath the crystallization point.
Consistent with the Clean Air Act of 1990 for systems using HCFC/HFC refrigerants, NuAire also uses a special mixture of azeotropic gases which can be non-flammable and allow on-site recycling. Additionally, a built-in timer cycles the reduced stage compressor every twenty four hours, turning it away in order that the capillary tubing is going to be cleared of ice formation.
So-Low Environmental Equipment Co. carries a long tradition of creating ultralow freezers for laboratory applications. In reality, with four decades of experience under its belt, So-Low is amongst the oldest manufacturers of ultralow temperature freezers in the industry. Once the Montreal Protocol started the phase out from CFC refrigerants in 1987, So-Low was among the first to make use of Dupont Suva 95, the new CFC-free refrigerant that runs cooler with less pressure than CFCs. Together with its investigation of eco friendly refrigerants, So-Low has developed a revolutionary compressor which is designed just 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 rather than the typical cylindrical containers. Each one of these cabinets is constructed of cold-rolled steel. Forma’s counterbalanced lids provide comfortable access, an optional thermal data printer continuously documents all operational functions, plus a storage system adjusts to allow for a selection of tube sizes. Forma also provides a patented double door unit that separates long term from everyday storage.
Revco is probably the largest manufacturers of laboratory freezers using more than fifty years of expertise in the industry. Revco’s Elite, Value, and Ultima mechanical freezers sustain temperatures from -10°C to only -120°C without CFC refrigerants and are available in chest, upright, and tabletop models. Its sophisticated Ultima freezers offer automatic electronic systems that constantly adjust conditions to the internal and external environment, correcting for subtle fluctuations in ambient temperature, excessive loading with warm samples, and dirty filters. In addition, it carries a scrubbing cycle that removes vaporized lubricating oil in the evaporating coils.
Sanyo has been manufacturing laboratory and medical freezers in excess of two decades, starting with its manufacture of the first -40°C chest freezer in 1974. Sanyo duplicated this achievement with the introduction of the first -152°C ultralow temperature freezer in 1991 and additional demonstrated its position by becoming the very first manufacturer to provide a complete array of CFC-free medical freezers. Today, Sanyo offers one of many largest selections of ultralow temperature lab freezers now available. Sanyo’s upright and chest freezers are equipped for use in preserving cells, bacteria, spores, pollen, sperm, protozoa, and blood components for academic and industrial research.
The word dewar, originally applied to double walled glass vacuum flasks, is currently used on a variety of insulated vessels created for repair of samples in liquid nitrogen. Depending on their size, dewars usually rest on the floor or sit on tabletops where samples can be accessed. As a result of quality of insulation materials, some dewars have maintained critical temperatures provided that 12 months without having to be regenerated with liquid nitrogen. The common thermal wall contains an aluminum or steel sandwich loaded with polyurethane. The shape and configuration of dewars vary to this kind of extent that a great many companies build custom dewars to buy. Many of these companies as well as their merchandise is reviewed within the following section.
From Alaskan salmon eggs to embryos from Idaho’s chicken farms, MVE makes laboratory freezers for numerous applications. Naturally, animal breeders are just a small number of its customers. Blood and cell storage in addition to organ shipment are an equally large part of MVE’s business with medical and pharmaceutical applications representing the fastest-growing area of the niche for the company’s products.
MVE was the initial company to build up biological freezers competent at maintaining a -190°C environment to get a full year without refilling with nitrogen. Since that point MVE has released the complete type of XLC series liquid and vapor-phase freezers. The XLC liquid nitrogen freezers are capable of handling up to 36,000 vials at temperatures as little as -195.8°C. The vapor-phase freezers are suitable for cells that can be stored at -125°C but can become damaged or discolored at critical temperatures achieved by liquid nitrogen freezers. The vapor-phase freezers are also helpful for storing hazardous materials that might cross-communicate within a liquid medium, for example contaminated-blood bags which are prone to break open.
Quantum Technology is really a worldwide manufacturer and supplier of laboratory freezers with offices in the states and Germany. Its product line includes everything from compressors and temperature sensors to gas wells and vacuum shrouds.
Based on Sean Wolf, product manager for Quantum Technology, one of the ways his company has managed to remain competitive is actually by offering on-site service and warranty repair. Another major selling point of Quantum’s refrigeration systems is they can be custom designed.
One among Quantum Technology’s most widely used products can be a helium recovery system. Although liquid helium is simply $4 or $5 per liter, in many countries outside America and Europe, the cost of purchasing helium is a concern of concern. That is probably the main reasons why Quantum Technology makes a reliable two-stage and three-stage closed-cycle refrigerator when the helium is retained from the system. The helium out of this refrigerator is reliquified for usage over and over.
Lab-Line Instruments, designer and manufacturer of dewars for scientific research and recently acquired subsidiary of Barnstead Thermolyne, offers a Thermo-Flask type of products that include wide-mouth flasks, insulated Thermo-Cups, stainless Thermo-Flasks, and enameled steel Thermo-Flasks. Twenty-six different models can be found with capacities from 200 cc to 10 liters, and every one of these models can be obtained having a 24-month warranty. Other special highlights of the Thermo-Flask collection of products include vented lids in order to avoid pressure build-up, fold-down handles, and borosilicate inner vessels evacuated to supply coolant retention for samples held in liquid nitrogen or solid CO2.
Barnstead Thermolyne manufactures the Bio-Cane and Locator Plus cryogenic storage systems, that happen to be distributed by a number of companies throughout the usa. The Bio-Cane systems can be found 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 can be found in four sizes and possess capacities up to 6,000 vials. Together with a few of the standard features contained in the Bio-Cane, the Locator provides hanging racks by using a gridded box design, audible and visual alarms that warn of low-level conditions, and an ultrasonic liquid level monitor that eliminates experience of liquid nitrogen and consequently reduces evaporation.
Pope Scientific makes many different traditional dewar flasks in “cylindrical,” “low form shallow,” and “spherical” styles. All Pope dewars are made of borosilicate glass covered by a protective mesh, and every wide-mouth model includes a vented polyethylene stopper to lower evaporation. Wide-mouth dewars may also be jacketed in aluminum casing for extra safety.
Pope Scientific’s narrow-mouth or “constricted-neck” dewars are designed for temporary storage or transfer applications with holding times greater than fourteen days. Every one of these units come equipped with a small-evaporation stopper, an entirely shielded evacuation tip, a weighted base, and protective mesh. Options 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 hold large amounts of semen, embryos, and biological samples at liquid-nitrogen temperatures. Every one of these units is complemented by its unique inventory control system, which is designed to maximize the quantity of vials that may be safely arranged in a canister-type storage device. By either immersing samples in liquid nitrogen or suspending them in nitrogen vapor, vials can be maintained at temperatures of -196° C.
Cryogenic Tubes are some of the most frequently used and least considered implements within the researcher’s tool box. Bags of tubes are stuffed into corners and forgotten until they mysteriously run out one day. Then its time to look shopping. Making decisions about buying cryogenic tubes is usually guided by three primary issues, the very first in which concerns the challenge of if they are externally or internally threaded. Advocates of externally threaded vials advise that material is trapped within the threads of internally threaded vials, while proponents from the internally threaded sort argue that externally threaded vials are more easily contaminated by accidental contact. Although research has been conducted so as to confirm or refute these claims, these have not been conclusive, and also the debate continues.
An additional consideration that comes into consideration when buying cryogenic tubes is definitely the material from which they may be constructed. While plastic vials are, perhaps, more durable than glass, they take more time to warm which might negatively affect the viability of some cells. Some plastic tubes can be contaminated with releasing fluids during the molding process. However, releasing fluids can be taken off together with the good care, plus some brands like Axygen are looking at new polished molds which do not require using releasing fluids. Glass, alternatively, warms rapidly but is additionally subjected to fracture due to microchannels which can form from the glass, causing leakage of sample contents, or perhaps violent explosions. Plastic vials can also be vunerable to nitrogen penetration but the potential for explosion is not as great.
Gasketing has been specifically a problem of some contention within this industry. Many cryovials include a washer that keeps the inner pressure of your vial from expelling the tube’s contents when it is warmed to ambient conditions. The rapid expansion of gas within the tube is sufficient to force cells and fluid throughout the lids of numerous non-gasketed cryotubes. Silicon is often preferred since the best material for insulating caps against leakage. Although rubber is likewise used, it has a tendency to get rid of its elasticity when dropped to freezing temperatures, a challenge that had been demonstrated as soon as the “O” rings around the space shuttle Challenger failed.
Simport Plastics, headquartered in Quebec, offers a large collection of cryotubes and microcentrifuge tubes which can be used at temperatures as low as -190°C. Intended for handling biological samples under freezing conditions for prolonged periods, its Cryovials™ come equipped with attached leak proof caps that include a dual lip and a silicon washer. A unique ridge on each cap makes handling easier, leading to one-hand aseptic technique, and color-coded cap inserts along with white marking areas make each vial easily identifiable.
Evergreen Scientific manufactures the CryoSure® type of vials for storing cell cultures, blood/serum specimens, sperm, and also other biological fluids at vapor-phase liquid nitrogen temperatures (-195°C). CryoSure vials can be found in 1. ml, 1.5 ml, and 3.5 ml sizes are available in round-bottom and freestanding configurations.
Evergreen even offers a wide selection of microcentrifuge tubes that range in capacities from 250 µ l to 2. ml. Some examples are polypropylene tubes, that may be used in combination with solvents, alcohols, chlorinated and aromatic hydrocarbons, and ketones. These tubes are sterilized using gamma radiation and are pressure tested within a vacuum chamber to be sure the reliability of its double-sealing screw caps.
Evergreen has designed a new microcentrifuge tube, in cooperation with Washington University Lipid Research Center, for usage in lipid fractionation studies. It really is a 1.5 ml polystyrene tube by having an 11 mm high-density polyethylene cap. Among the outstanding features of this tube is it is entirely transparent.
Nalgene® and Nunc™ cryogenic vials include a range of externally and internally threaded vials from 1. to 5. ml capacities that are silicone gasketed and guaranteed for usage within a centrifuge. The Nalgene 5000 series vials feature graduations and are certified to be sterile, noncytotoxic and nonpyrogenic, while the System 100 vials are guaranteed to be leakproof in the microcentrifuge around 8,000 g and throughout shipment and transport. However, the corporation warns that cryotubes improperly sealed in liquid phase can result in 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 a substantial catalog of products for handling liquid samples. Wheaton’s Cryules® can be purchased in both plastic and glass. The glass Cryule is manufactured out of Wheaton-33° low extractable glass that may be hermetically sealed. These are generally most suitable for that preservation of biological materials with liquid nitrogen at low temperatures. Wheaton’s plastic Cryules are autoclavable and, like each of the glass Cryules, can withstand temperatures between -196°C and 121°C. Wheaton Vacules are vials that are constructed for lyophilization and freeze-drying. Their heavy-wall construction ensures they are exceptionally durable, and they are often flame sealed or stored with a wide selection of stoppers and caps.
Corning Incorporated Science Products Division makes several polypropylene vials that are designed 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 easy-to-read graduations for partial volumes. Self-standing and locking features can be found with selected styles. Most 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 that 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 like iron, chromium, or nickel that happen to be typical constituents of dyes. Each one of the company’s vials was designed 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 comes with a patent-pending alignment system that guarantees that this microtube is aligned in the centrifuge rotor to become re-spun without disturbing the pelletized sediment.
Sarstedt Inc. has a extensive catalog of microcentrifuge tubes which can be ideal for both freezing at ultralow temperatures and centrifugation that come in an assortment of sizes, shapes, and colours. An individual has a choice of choosing from many different externally threaded microtubes with attached or enclosed screw caps that could be colored for identification. All Sarstedt’s tubes are sterile, along with the polypropylene material through which they can be constructed enables them to endure subfreezing temperatures along with temperatures and pressures within an autoclave. One of several areas that Sarstedt has paid particular focus on in developing its type of products is the necessity for cryogenic vials which contain 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 can be purchased in conical and skirted configurations. Stockwell’s microcentrifuge tubes can be subjected to a centrifugal force of 20,000 g and every one of its O-ring sealed tubes is sterilized.
Storage inventory systems can be a critical part of any long-term protocol for cryogenic preservation. Once cryogenic vials are stored at subfreezing temperatures they can undergo changes that can make them difficult to keep trace. Labels can be brittle, breaking and separating from vials, and improperly stored tubes can be dropped into liquid nitrogen making retrieval difficult and costly. One of the more popular methods for containing samples will be the canister and cane. Employing this technique, some vials are enclosed within a long aluminum shaft which is submerged within liquid nitrogen. The canes can be simply manipulated for small sample volumes and protect vials from damage that may occur from bumping or agitation. For greater storage capacities, however, the drawer method is usually preferred. Although drawer systems have a tendency to expose more samples to warming during exchange, the accessibility in the system reduces exposure time and energy to ambient temperatures leading to less evaporation from the freezer, plus cuts down on the researcher’s contact with possibly damaging cryogens.
Forma Scientific makes rack inventory systems for liquid-phase and vapor-phase storage. These racks are meant to optimize the volume of storage area afforded by Forma’s liquid nitrogen containers. The regular inventory configuration is really a cardboard or steel construction arranged into arrowhead or square designs. Vertical inventory systems let the user to organize approximately 82 racks at maximum density.
TetraLink International specializes in making storage boxes and rack systems for cryogenic storage. Designed for the widest possible applicability, its freezer storage systems are available in numerous sizes, shapes, and colors to match virtually any freezer. Clear lids allow contents to be viewed without opening the containers, and they could be adjusted in some 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 as much as 267 microtubes. These drawers could be installed in any upright freezer or refrigerator.
Nalgene and Nunc storage systems comprise a number of plastic or chipboard containers for microcentrifuge tubes and glass vials. These are generally keyed to avoid misalignment and provide temperature resistance from -196°C to 121°C.
Nalgene® CryoBox Racks provide stainless-steel retainer systems appropriate for all Nalgene and Nunc storage boxes. They have vertical and horizontal storage for boxes that maintain each box separately for quick retrieval.
National Labnet provides freezer racks and storage boxes to have an increasing number of sample containers. As high-throughput experiments require greater reserves of reagents, Cryogenic Movable tank has responded with boxes and racks that are constructed for numerous examples of both well plates and cryovials. They have also introduced boxes with telescoping lids in order to satisfy requirements for single box containers with vials of differing sizes.
Custom Biogenic Systems is one of the largest manufacturers of rack systems for cryogenic storage containers. Actually, many 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 choice of cardboard, aluminum, or stainless boxes with 1/2 inch or 5/8″ cell dividers. These systems can be purchased as individual units or as complete racks to be used in vapor- phase or liquid-phase storage.
Probably, the cryogenic products one buys today is definitely the same ones that might be used for a long time. A purchase made today may go on for ten years. Essentially, researchers buying Gas Cylinder are not just buying products by themselves, they are buying for their successors. The consumer should look into what might 46dexkpky during the period of years if their samples become degraded or contaminated on account of improper storage. A little bit money which had been saved at the beginning by scrimping on vials or freezers may well not appear to be the best trade off when valuable samples are lost. Despite the safeguards internal to the majority of these devices many product managers recommend making regular maintenance on these products important. Appointing a lasting position that is accountable for the cryogenic safety of your laboratory’s biological collection is one of the best ways to assure the integrity of the samples.