Everything below concerns Sublimation. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Last reviewed on 2026-06-16. Where a claim depends on a specific study, the study is described rather than over-claimed.
Lyophilized products are typically hygroscopic and require protection from moisture during storage. Manufacturers seal them in glass vials, often under vacuum or an inert gas such as nitrogen. The container closure system, including the stopper and crimp seal, must prevent water vapor ingress. Storage temperature varies from controlled room temperature to refrigerated or frozen conditions, depending on the formulation. Humidity-controlled environments are essential because even brief exposure to ambient air can degrade the product.
Stability of a lyophilized product depends on its glass transition temperature, the temperature at which the amorphous cake transitions from a glassy to a rubbery state. Storage below this temperature minimizes molecular mobility and slows chemical degradation. If the storage temperature exceeds the glass transition temperature, the cake may collapse, shrink, or become sticky. Accelerated stability studies at elevated temperatures and humidity help predict shelf life, but they do not always reflect real-time behavior. Residual moisture content also plays a critical role in long-term stability.
Reconstitution involves adding a suitable diluent, often sterile water or a buffer, to the dried cake. Gentle swirling or inversion helps dissolve the material without creating excessive foam. The time required for complete dissolution can range from seconds to several minutes and depends on the cake structure and the diluent. Improper reconstitution, such as vigorous shaking or using the wrong diluent, can cause protein aggregation or loss of activity. After reconstitution, the product may have a limited shelf life and should be used according to its labeling.
Lyophilization is a dehydration technique in which a product is frozen and the solvent is removed under reduced pressure. The low pressure allows ice to sublimate directly into vapor without passing through a bulk liquid phase. This differs from conventional drying, where heat drives evaporation and can damage heat-sensitive structures. The process is used for biological materials, pharmaceutical formulations, and some foods. Its main advantage is preservation of porous structure and rapid reconstitution.
Freezing is the first stage and sets the ice structure that later becomes the pore network. The formulation is cooled below its freezing point, often with a controlled ramp, and solutes concentrate as ice forms. Primary drying then lowers chamber pressure and supplies heat to sublime the ice. The product temperature must stay below its collapse or eutectic temperature to prevent structural loss. Secondary drying raises the temperature modestly to remove bound water and achieve a low residual moisture.
A freeze-dryer consists of a vacuum chamber, temperature-controlled shelves, a condenser, and a vacuum pump. Vials, ampoules, or bulk trays hold the product during the cycle. The condenser traps water vapor as ice at a temperature lower than the product. Cycle development balances shelf temperature, chamber pressure, and time. Scale-up can be difficult because heat and mass transfer change with equipment size, so process analytical tools and conservative validation are often used.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white porous cake | Color depends on formulation. |
| Typical storage temperature | 2–8 °C | Refrigerated for many biologics. |
| Residual moisture | <1% to 3% | Low moisture improves stability. |
| Container | Sealed glass vial | Often with rubber stopper and aluminum crimp. |
| Reconstitution time | Seconds to minutes | Varies with cake density and diluent. |
Stability studies examine how temperature, humidity, and time influence a lyophilized product. Accelerated conditions provide early information about degradation pathways, while long-term studies support shelf-life claims. The glass transition temperature of the dried formulation can indicate its physical stability, and storage above this temperature may increase molecular mobility and lead to collapse or aggregation. Container closure integrity also matters because moisture or oxygen ingress can degrade the product, so vial stoppers and seals are part of the quality system.
Handling and storage practices aim to keep the cake intact and dry. Vials are typically stored upright at controlled temperatures, often between 2 °C and 8 °C or at -20 °C for longer-term use. Reconstitution involves adding a suitable diluent and gently mixing until the solid dissolves. Shaking or rapid injection of diluent can create foam or damage sensitive molecules. Once reconstituted, the product may require refrigeration and use within a defined period.
Secondary drying removes bound water that remains after ice sublimation. Shelf temperature is raised gradually while pressure remains low, reducing water content to a target range. Over-drying can cause brittleness or electrostatic issues, while under-drying affects stability. The endpoint is often judged by pressure rise tests, temperature measurements, or water content analysis. Scale-up depends on matching heat and mass transfer across equipment sizes. Small changes in shelf temperature or pressure can alter cycle length substantially.
Lyophilization, or freeze-drying, removes water from a material by freezing it and then lowering pressure so ice changes directly to vapor. The process relies on sublimation, the phase transition from solid to gas without an intervening liquid state. It is used for heat-sensitive materials that would degrade in conventional drying. The three stages are freezing, primary drying, and secondary drying, each with distinct temperature and pressure requirements. In practice, cycle design balances these variables.
Freezing determines ice crystal structure and pore size, which affect drying speed and product uniformity. Rapid freezing creates small crystals, while slow freezing creates larger crystals and often faster sublimation. During primary drying, chamber pressure is held below the vapor pressure of ice, and shelf temperature supplies heat for sublimation. The ice front recedes, leaving a porous matrix. Thermal limits such as collapse and eutectic temperatures set safe boundaries for formulation. These limits vary with solute composition and concentration.
Moving forward, you'll see the DC movie universe being a universe, but one that comes from the heart of the filmmaker who's creating them." Additionally, DC began focusing on films "completely separate from everything else, set entirely outside" the DCEU as part of a new label, with the first film centered on the Joker. Following the commercial failure of Justice League (2017), which ended the DCEU approach spearheaded by Snyder, Warner Bros. executives reportedly reached out to Feige to have him lead the development of DC films but the talks "fizzled". In August 2022, Warner Bros. Discovery CEO David Zaslav announced a 10-year plan for the DC Extended Universe similar to the one that Horn and Iger employed with Feige for the MCU, with James Gunn and Peter Safran appointed in October 2022 to serve as the co-chairmen and co-CEOs of the newly formed DC Studios to develop a new shared universe, the DC Universe, the first content for which was announced in January 2023. By July 2024, both Feige and Gunn had expressed interest in one day creating a crossover between the two franchises, though both noted it was not something actively being discussed or considered. Gunn revealed following the second-season finale of Peacemaker in October 2025, that he had wanted to show Wade Wilson / Deadpool behind one of the alternate universe doors in the Quantum Unfolding Chamber and had reached out to Deadpool actor Ryan Reynolds about it, who was interested in appearing.
=== Animal === Laboratory tests assessing the toxicity of chlordiazepoxide, nitrazepam and diazepam on mice spermatozoa found that chlordiazepoxide produced toxicities in sperm including abnormalities involving both the shape and size of the sperm head. Nitrazepam, however, caused more profound abnormalities than chlordiazepoxide.
=== Medicaid and illegal immigrants === The bill prompted claims that illegal immigrants receive Medicaid. Illegal immigrants are already ineligible for full Medicaid benefits under the Personal Responsibility and Work Opportunity Act, so many illegal immigrants access state-funded health programs instead. According to a CBO analysis, the bill's provisions could lead some states to cut back those state-funded health programs, potentially causing an estimated 1.4 million people to lose state-level health coverage, including illegal immigrants.
Sources: en.wikipedia.org
In the backlash that followed, members of several caucuses called for Barranzuela's resignation. and threatened not to give a vote of confidence to Mirtha Vásquez's cabinet if he remained in office. The Ombudsman's Office issued a statement in its social networks reminding the citizens, and especially those in high positions, that they must comply with sanitary measures to counteract COVID-19 infections. The president of the Congressional Defense Committee, José Williams, informed that Barranzuela had been summoned on 3 November, to answer for the party in his house. The president of the Judicial Power, Elvia Barrios, said that "the law has to be applied equally to all, if there is a sanction, there has to be a sanction, the law is the same for all". Barranzuela met with President Castillo on the afternoon of 2 November at the Government Palace. He left moments after the arrival of premier Mirtha Vásquez, who a day earlier called his meeting "unacceptable". In the evening, Barranzuela made his resignation official, two days after the party was held, but rejected the accusations against him. On 4 November 2021, the cabinet received the approval of Congress, with 68 votes in favor, 56 against and one abstention, and Avelino Guillén was sworn in as the new Interior Minister.
The fetal immune system can be described as 'immunologically immature' due to the marked reduction in neutrophils, macrophages, monocytes, lymphocytes and also inflammatory mediators, compared with adult wounds. Physiologically, adult and fetal neutrophils differ, due to the fact that the concentration of neutrophils is higher in the adult than the fetus, this results in phagocytosis of the wound and the recruitment and release of inflammatory cytokines. Leading to the promotion of a more aggressive inflammatory response in adult wound healing. It is also thought that the time in which this inflammatory response occurs, is much shorter in the fetus thus limiting any damage.
The four substrates of this enzyme are 3-hydroxybenzenepropanoic acid, reduced nicotinamide adenine dinucleotide (NADH), oxygen, and a proton. Its products are 2,3-dihydroxyphenylpropionic acid, oxidised NAD+, and water. It is a flavoprotein that uses flavin adenine dinucleotide as a cofactor. The enzyme can act on related substrates, for example to convert 3'-hydroxycinnamic acid to 2,3-dihydroxycinnamic acid:
Chinese hamster ovary cell Mouse myeloma lymphoblstoid (e.g. NS0 cell) Fully Human Human embryonic kidney cells (HEK-293) Human embryonic retinal cells (Crucell's Per.C6) Human amniocyte cells (Glycotope and CEVEC)
Sources: en.wikipedia.org
The Selous Scouts was a special forces unit of the Rhodesian Army that operated during the Rhodesian Bush War from 1973 until the reconstitution of the country as Zimbabwe in 1980. It was mainly responsible for infiltrating the black majority population of Rhodesia and collecting intelligence on insurgents so that they could be attacked by regular elements of the security forces. The unit did this by forming small teams that posed as insurgents and usually included captured insurgents. Over time, the Selous Scouts increasingly attacked insurgents themselves and operated in the countries that neighboured Rhodesia. The unit developed a reputation for brutality and was responsible for attacking and killing civilians. The Selous Scouts were also involved in the Rhodesian chemical and biological weapons programme and used poisons and biological agents in some of its operations. The methods used by the unit led to the deaths of large numbers of insurgents, but proved counter-productive as they further alienated the black majority population from the white minority Rhodesian government and increased international opposition to the regime. Following the disbandment of the Selous Scouts after Rhodesia's transition to Zimbabwe, many of its members were recruited into the Apartheid-era South African security forces. They contributed to the adoption of the Selous Scouts' methods by the South African Defence Force and South African Police, and some took part in operations to undermine the government of Zimbabwe.
This phenomenon was used in the design of light meters and similar devices. Selenium's semiconductor properties found numerous other applications in electronics. The development of selenium rectifiers began during the early 1930s, and these replaced copper oxide rectifiers because they were more efficient. These lasted in commercial applications until the 1970s, following which they were replaced with less expensive and even more efficient silicon rectifiers. Selenium came to medical notice later because of its toxicity to industrial workers. Selenium was also recognized as an important veterinary toxin, which is seen in animals that have eaten high-selenium plants. In 1954, the first hints of specific biological functions of selenium were discovered in microorganisms by biochemist, Jane Pinsent. It was discovered to be essential for mammalian life in 1957. In the 1970s, it was shown to be present in two independent sets of enzymes. This was followed by the discovery of selenocysteine in proteins. During the 1980s, selenocysteine was shown to be encoded by the codon UGA. The recoding mechanism was worked out first in bacteria and then in mammals (see SECIS element).
=== In eukaryotes === As with any protein or RNA, rRNA production is prone to errors resulting in the production of non-functional rRNA. To correct this, the cell allows for degradation of rRNA through the non-functional rRNA decay (NRD) pathway. Much of the research in this topic was conducted on eukaryotic cells, specifically Saccharomyces cerevisiae yeast. Currently, only a basic understanding of how cells are able to target functionally defective ribosomes for ubiquination and degradation in eukaryotes is available.
=== FA2; 1967 === The new Familia appeared in November 1967 with the same pushrod 987 cc engine as used in the previous generation saloons. It was sold as the "Mazda 1000" in some markets. In July 1968 the rotary-engined version (R100) was introduced, along with a new coupé bodywork which was also available with the 1200 cc piston engine. After an April 1970 facelift (called the "Familia Presto" in the domestic Japanese market), the slightly different OHC "PC" 1-litre engine was also offered. A larger 1169 cc straight-four engined version came along in February 1968, becoming the "Mazda 1200" for export. In this form, the car was first exhibited in Europe at the 1968 Paris Motor Show in the autumn of that year. Power outputs (SAE gross) in Japan of the facelifted, overhead-cam-engined versions were 62 and 75 PS (46 and 55 kW) respectively. The Van (wagon) model was available with either three or five doors, although most export markets only received the five-door version.
=== Iraq === In a March 2000 article in The Guardian, Galloway described himself as a supporter of the Iraqi people and the Ba'ath Party, but not Saddam Hussein himself. In a House of Commons debate on 6 March 2002, Foreign Office minister Ben Bradshaw said Galloway was "not just an apologist, but a mouthpiece, for the Iraqi regime over many years." Galloway called the minister a liar and refused to withdraw on the grounds that Bradshaw's claim was "a clear imputation of dishonour", and the sitting was suspended due to the dispute. Bradshaw later withdrew his allegation, and Galloway apologised for using unparliamentary language. Giving evidence in his libel case against The Daily Telegraph in 2004, Galloway testified that he regarded Saddam as a "bestial dictator" and would have welcomed his removal from power, but not by means of a military attack on Iraq. Galloway also pointed out that he was a prominent critic of Saddam Hussein's government in the 1980s, as well as of the role of Margaret Thatcher's government in supporting arms sales to Iraq during the Iran–Iraq War.
Sources: en.wikipedia.org
Lyophilized products should be stored in airtight containers, protected from moisture and light, at the temperature specified by the manufacturer. Many require refrigeration at 2–8 °C, while some need frozen storage. Always check the product label for specific conditions.
Moisture can cause the porous cake to collapse, increase molecular mobility, and accelerate chemical degradation. It may also promote microbial growth if the product lacks preservatives. Proper sealing and handling are essential to maintain stability.
Some formulations contain labile biological molecules that degrade even in the dry state at higher temperatures. Others have a low glass transition temperature, meaning the cake can soften or collapse at room temperature. Cold storage reduces molecular motion and slows degradation.
Yes, the terms are generally interchangeable. Lyophilization is more common in pharmaceutical and laboratory contexts, while freeze-drying appears widely in food science and general writing. Both describe removal of solvent by sublimation under vacuum after freezing.