“Time is the fire we burn in.” And even though we could be unable to quench its unrelenting flame, scientists have attempt to divert its path by isolating small enclosures where time slows to some crawl. Within these chambers the frenetic Brownian dance becomes a chaperoned waltz, as temperatures approach absolute zero. The internal environment of Air separation equipment is really a world apart, a reminder in the ultimate heat-death that has to befall our universe from the eons in the future.
For people who attempt to discover truths in regards to the workings of your cell, holding back the floodgates of your time is a problem of significant proportions. Scientists tend to be considering very specific cell properties that take place at critical junctions within the lifetime of a cell. Holding these processes away while their properties can be exploited is akin to the trouble of catching one’s shadow.
Cryogenic freezing of cells has been utilized as you means to fix the situation in the slow burn. By reducing the temperatures of samples for the glass transition phase of -133°C, the temperature from which all metabolic activity comes to a halt, scientists can easily seclude moments in time, returning time and again to analyze that instant in the past.
Not surprisingly, cryogenics has become an essential industry that makes customized products for up to every conceivable purpose. From small tabletop apparatus to industrial-scale liquifiers, the industry in cryogenics provides mechanical freezers, storage containers, and dewars in just about every size, shape, and configuration imaginable. By using these a wide variety of products to choose from knowledge of the ones that are most efficient may elude the typical consumer. To be able to provide a summary of the main producers of cryogenic laboratory supplies several manufacturers will be profiled in the following paragraphs.
Ultra-low lab freezers are one of those stuff that a lot of people never take into consideration until they quit working. Made to run for several years without interruption in service, lab freezers are definitely the quiet sentinels in the laboratory, keeping a vigilant watch within the researcher’s most prized possessions. Most scientists try to avoid the very thought of what might happen if their freezer failed, or they attempt to erase the memory of the day whenever it did. A career’s amount of samples might be lost in just one afternoon– numerous years of careful collecting and cataloging reduced to mere puddles on to the ground. Even though this sort of scenario looms ominously from the periphery of each and every researcher’s consciousness, not many are prepared for a day whenever it actually occurs. Manufacturers of ultra-low lab freezers have got great pains to make certain that power failures and refrigerant leaks will never compromise one’s samples. They build machines that are intended to be forgotten.
MMR Technologies may be the only company that utilizes the Kleemenko cooling cycle in its refrigerators. Even though the gas industry provides this procedure for many years, MMR Technologies was the very first company to patent the technology and adapt it for really small, lightweight, and portable freezing systems.
How the Kleemenko cycle works is the fact that an assortment of compressed gas and liquid is passed down a countercurrent exchanger and is permitted to expand via a capillary or throttling valve. Cooling occurs upon expansion, and also the cool gas passes backup the temperature exchanger, precooling the incoming high-pressure gas. A number of liquid-vapor separators may be incorporated within the cycle so the increase of the liquid could be used 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 for storing frozen tissue, cell cultures, organs, and the body parts. The system allows the scientist to warm and funky samples uniformly without shocking them, and furthermore, as it provides an inside power source you can use it to the transportation of samples from storage facility to check out laboratory. Robert Paugh, product manager for MMR Technologies, was insistent on the requirement for controlled temperature ramping.
“As being a user you wish to are aware of the minimum temperature and the way it gets there,” said Paugh. MMR Technologies’ enhanced control systems and printed thermal record of cooling makes sure that uniform temperatures happen to be maintained throughout the cooling process.
Kelvinator Scientific, that is a subsidiary of Frigidaire, provides freezer units for laboratories and pharmacies that are designed for biological samples at temperatures as a result of -86°C. At temperatures this low animal and plant viruses, bacteria, spores, and bacteriophages can be preserved for prolonged periods. Locking lids are provided in order to protect samples from accidental exposure to ambient temperatures. Adjustable shelving, pullout drawers, and drawer partition inserts are helpful for separating different experiments.
NuAire, Inc. credits much of its ultralow freezing capabilities to the heavy-gauge galvanized steel cabinets. The temperature-conducting quality of 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 can perform holding samples below the crystallization point.
In line with the Clean Air Act of 1990 for systems using HCFC/HFC refrigerants, NuAire also works with a special mix of azeotropic gases which are non-flammable and permit on-site recycling. Additionally, a built in timer cycles the low stage compressor every twenty four hours, turning it away so the capillary tubing will likely be cleared of ice formation.
So-Low Environmental Equipment Co. features a long tradition of creating ultralow freezers for laboratory applications. Actually, with forty years of experience under its belt, So-Low is among the oldest manufacturers of ultralow temperature freezers in the industry. When the Montreal Protocol started the phase from CFC refrigerants in 1987, So-Low was among the first to utilize Dupont Suva 95, the newest CFC-free refrigerant that runs cooler along with less pressure than CFCs. In addition to its investigation of eco friendly refrigerants, So-Low also has developed a revolutionary compressor which is designed mainly 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 right down to -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 as an alternative to the standard cylindrical containers. All 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, and a storage system adjusts to allow for a range of tube sizes. Forma also provides a patented double door unit that separates long lasting from everyday storage.
Revco is among the largest manufacturers of laboratory freezers with more than half a century of expertise in the market. Revco’s Elite, Value, and Ultima mechanical freezers sustain temperatures from -10°C to as low as -120°C without CFC refrigerants and can be bought in chest, upright, and tabletop models. Its sophisticated Ultima freezers offer automatic electronic systems that constantly adjust conditions for the external and internal environment, correcting for subtle fluctuations in ambient temperature, excessive loading with warm samples, and dirty filters. Furthermore, it has a scrubbing cycle that removes vaporized lubricating oil in the evaporating coils.
Sanyo has become manufacturing laboratory and medical freezers in excess of two decades, starting with its creation of the first -40°C chest freezer in 1974. Sanyo duplicated this achievement with the growth of the 1st -152°C ultralow temperature freezer in 1991 and additional demonstrated its position by becoming the first manufacturer to provide a complete selection of CFC-free medical freezers. Today, Sanyo offers one of several largest selections of ultralow temperature lab freezers on the market today. Sanyo’s upright and chest freezers are designed for use within preserving cells, bacteria, spores, pollen, sperm, protozoa, and blood components for academic and industrial research.
The expression dewar, originally used on double walled glass vacuum flasks, is already placed on a wide array of insulated vessels created for maintenance of samples in liquid nitrogen. Depending upon their size, dewars usually rest on to the floor or sit down on tabletops where samples can be accessed. Because of the quality of insulation materials, some dewars have maintained critical temperatures provided that one year without being regenerated with liquid nitrogen. The normal thermal wall is made up of an aluminum or steel sandwich loaded with polyurethane. The dimensions and configuration of dewars vary to this kind of extent that numerous companies build custom dewars to acquire. Some of these companies as well as 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. Naturally, animal breeders are just a small portion of its customers. Blood and cell storage and also organ shipment are an equally large component of MVE’s business with medical and pharmaceutical applications representing the fastest-growing part of the niche for the company’s products.
MVE was the initial company to develop biological freezers capable of maintaining a -190°C environment for any full year without refilling with nitrogen. Since that time MVE has released the total collection of XLC series liquid and vapor-phase freezers. The XLC liquid nitrogen freezers are designed for handling as many as 36,000 vials at temperatures only -195.8°C. The vapor-phase freezers are suitable for cells that could be stored at -125°C but could 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 might cross-communicate within a liquid medium, like contaminated-blood bags which are prone to break open.
Quantum Technology is actually a worldwide manufacturer and supplier of laboratory freezers with offices in the United States and Germany. Its product line includes 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 managed to remain competitive is simply by offering on-site service and warranty repair. Another major selling point of Quantum’s refrigeration systems is they may be custom designed.
One of Quantum Technology’s most in-demand products is a helium recovery system. Although liquid helium is just $4 or $5 per liter, in several countries outside of North America and Europe, the fee for purchasing helium is an issue of concern. That is one of the reasons why Quantum Technology makes a competent two-stage and three-stage closed-cycle refrigerator wherein the helium is retained from the system. The helium using this refrigerator is reliquified to use 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 line of products that include wide-mouth flasks, insulated Thermo-Cups, stainless Thermo-Flasks, and enameled steel Thermo-Flasks. Twenty-six different models are offered with capacities from 200 cc to 10 liters, and each of these models is accessible by using a 24-month warranty. Other special highlights of the Thermo-Flask brand of products include vented lids to avoid pressure build-up, fold-down handles, and borosilicate inner vessels evacuated to provide coolant retention for samples stored in liquid nitrogen or solid CO2.
Barnstead Thermolyne manufactures the Bio-Cane and Locator Plus cryogenic storage systems, that are distributed by a variety of companies throughout america. The Bio-Cane systems can be bought in five sizes and give features including 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 up to 6,000 vials. Along with a number of the standard features present 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, as well as 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 paid by a protective mesh, and each and every wide-mouth model carries a vented polyethylene stopper to lower evaporation. Wide-mouth dewars can even be jacketed in aluminum casing for more safety.
Pope Scientific’s narrow-mouth or “constricted-neck” dewars are suitable for temporary storage or transfer applications with holding times greater than 14 days. Most of these units come built with a low-evaporation stopper, a completely shielded evacuation tip, a weighted base, and protective mesh. Alternatives for these instruments include fiberglass caddies for carrying or decanting.
Taylor-Wharton International definitely makes the K Series, XT (Extended Time), HC (High Capacity), and RS (Rack System) dewars that enable the researcher to save large volumes of semen, embryos, and biological samples at liquid-nitrogen temperatures. Each of these units is complemented by its very own inventory control system, which was created to maximize the quantity 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 can be maintained at temperatures of -196° C.
Cryogenic Tubes are among the most frequently 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 one day. Then its time to visit shopping. Making decisions about buying cryogenic tubes is often guided by three primary issues, the 1st of which concerns the issue of if they are externally or internally threaded. Advocates of externally threaded vials propose that material is trapped inside the threads of internally threaded vials, while proponents from the internally threaded sort reason that externally threaded vials are definitely more easily contaminated by accidental contact. Although reports have been conducted in order to confirm or refute these claims, these have not been conclusive, and the debate continues on.
Another consideration which comes into account when selecting cryogenic tubes will be the material that these are constructed. While plastic vials are, perhaps, more durable than glass, they be more difficult to warm which might negatively change the viability of some cells. Some plastic tubes may also be contaminated with releasing fluids during the molding process. However, releasing fluids can be removed with the good care, plus some companies like Axygen are switching to new polished molds that do not require using releasing fluids. Glass, however, warms rapidly but can also be at the mercy of fracture on account of microchannels which may form within the glass, causing leakage of sample contents, or perhaps violent explosions. Plastic vials may also be vunerable to nitrogen penetration but the potential for explosion will not be as great.
Gasketing has also been a problem of some contention in this industry. Many cryovials come with a washer that keeps the interior pressure in the 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 with the lids of many non-gasketed cryotubes. Silicon is usually preferred since the best material for insulating caps against leakage. Although rubber is additionally used, it comes with a tendency to shed its elasticity when dropped to freezing temperatures, a problem which was demonstrated once the “O” rings around the space shuttle Challenger failed.
Simport Plastics, headquartered in Quebec, gives a large selection of cryotubes and microcentrifuge tubes that can be used at temperatures only -190°C. Intended for handling biological samples under freezing conditions for prolonged periods, its Cryovials™ come provided with attached leak proof caps that comprise of a dual lip and a silicon washer. A particular ridge on each cap makes handling easier, contributing to one-hand aseptic technique, and color-coded cap inserts in combination 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, as well as other biological fluids at vapor-phase liquid nitrogen temperatures (-195°C). CryoSure vials can be bought in 1. ml, 1.5 ml, and three.5 ml sizes and come in round-bottom and freestanding configurations.
Evergreen also provides a wide range of microcentrifuge tubes that range in capacities from 250 µ l to 2. ml. Included in this are polypropylene tubes, which may be used in combination with solvents, alcohols, chlorinated and aromatic hydrocarbons, and ketones. These tubes are sterilized using gamma radiation and therefore are pressure tested in the vacuum chamber to guarantee the reliability of its double-sealing screw caps.
Evergreen has developed a new microcentrifuge tube, in cooperation with Washington University Lipid Research Center, for use in lipid fractionation studies. It is a 1.5 ml polystyrene tube having an 11 mm high-density polyethylene cap. One of many outstanding options that come with this tube is it is utterly transparent.
Nalgene® and Nunc™ cryogenic vials include a selection of externally and internally threaded vials from 1. to 5. ml capacities that are silicone gasketed and guaranteed to use within a centrifuge. The Nalgene 5000 series vials feature graduations and are certified to become sterile, noncytotoxic and nonpyrogenic, even though the System 100 vials are guaranteed to be leakproof inside a microcentrifuge up to 8,000 g and through shipment and transport. However, the business 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 pretty much every eventuality. From serum bottles to mobile phase reservoirs, it provides developed an extensive catalog of items for handling liquid samples. Wheaton’s Cryules® are available in both plastic and glass. The glass Cryule is constructed from Wheaton-33° low extractable glass that could be hermetically sealed. These are suitable for the preservation of biological materials with liquid nitrogen at low temperatures. Wheaton’s plastic Cryules are autoclavable and, like all 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 means they are exceptionally durable, and they can be flame sealed or stored by using a wide selection 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 easy-to-read graduations for partial volumes. Self-standing and locking features are available with selected styles. All 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 happen to be designed with 99.9 percent pure polypropylene with no mineral fillers or heavy metals. Foreign substances are added only at the request from the customer, and Axygen’s colorants contain no metallic ions like iron, chromium, or nickel which are typical constituents of dyes. Each of the company’s vials was designed to snap closed in a locked position for centrifugation, and special piercing ports have the insertion of syringes easier for collecting samples. Axygen’s “O” ring closure system incorporates a patent-pending alignment system that guarantees that the microtube is aligned inside the centrifuge rotor to be re-spun without disturbing the pelletized sediment.
Sarstedt Inc. has a extensive catalog of microcentrifuge tubes that happen to be right for both freezing at ultralow temperatures and centrifugation that could come in a variety of sizes, shapes, and colours. The consumer has a choice of choosing from a variety of externally threaded microtubes with attached or enclosed screw caps which may be colored for identification. Each one of Sarstedt’s tubes are sterile, as well as the polypropylene material that these are constructed allows them to endure subfreezing temperatures as well as temperatures and pressures in a autoclave. One of the areas that Sarstedt has paid particular awareness of in developing its line of products is the requirement 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 can be found in conical and skirted configurations. Stockwell’s microcentrifuge tubes may be exposed to a centrifugal force of 20,000 g and every one of its O-ring sealed tubes has become sterilized.
Storage inventory systems are a critical element of any long term protocol for cryogenic preservation. Once cryogenic vials are stored at subfreezing temperatures they may undergo changes which make them hard to keep trace. Labels can be brittle, breaking and separating from vials, and improperly stored tubes may be dropped into liquid nitrogen making retrieval difficult and costly. One of the most popular techniques for containing samples is the canister and cane. Applying this technique, several vials are enclosed in a long aluminum shaft which is submerged within liquid nitrogen. The canes can be manipulated for small sample volumes and protect vials from damage that may 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 time and energy to ambient temperatures resulting in less evaporation in the freezer, plus lessens the researcher’s contact with potentially harmful cryogens.
Forma Scientific makes rack inventory systems for liquid-phase and vapor-phase storage. These racks are made to optimize the volume of storage space afforded by Forma’s liquid nitrogen containers. The regular inventory configuration can be a cardboard or steel construction arranged into arrowhead or square designs. Vertical inventory systems permit the user to set up up to 82 racks at maximum density.
TetraLink International specializes in making storage boxes and rack systems for cryogenic storage. Made for the widest possible applicability, its freezer storage systems are available in a multitude of sizes, shapes, and colors to fit nearly every freezer. Clear lids allow contents being viewed without opening the containers, and they could be adjusted in certain models to allow for 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 many as 267 microtubes. These drawers may be installed in almost any upright freezer or refrigerator.
Nalgene and Nunc storage systems comprise several plastic or chipboard containers for microcentrifuge tubes and glass vials. These are typically keyed to prevent misalignment and supply 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 easy retrieval.
National Labnet provides freezer racks and storage boxes to have an increasing selection of sample containers. As high-throughput experiments require greater reserves of reagents, Cryogenic ISO Tank Container has responded with boxes and racks that happen to be constructed for numerous samples of both well plates and cryovials. They also have introduced boxes with telescoping lids so that you can satisfy requirements for single box containers with vials of differing sizes.
Custom Biogenic Systems is amongst the largest manufacturers of rack systems for cryogenic packing containers. The truth is, several of its products are sold as standard accessories with several of the major producers of laboratory freezers. Its pie-shaped racks are built from stainless-steel and may include a selection of cardboard, aluminum, or steel boxes with 1/2 inch or 5/8″ cell dividers. These systems can be acquired as individual units or as complete racks to be used in vapor- phase or liquid-phase storage.
Almost certainly, the cryogenic products one buys today is definitely the same ones that will be used for years to come. An order made today may work for ten years. In place, researchers buying Cryogenic Centrifugal Pump are not just buying products for their own reasons, they may be buying for successors. The customer should consider what might 46dexkpky during the period of years if their samples become degraded or contaminated because of improper storage. Just a little money that was saved initially by scrimping on vials or freezers might not exactly appear to be the best trade off when valuable samples are lost. In spite of the safeguards internal to most of these devices many product managers recommend making regular maintenance on these products a high priority. Appointing a lasting position that is accountable for the cryogenic safety from the laboratory’s biological collection is among the guidelines on how to assure the integrity of these samples.