The short version of Collapse temperature fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
Quality control for lyophilized products includes appearance, cake structure, reconstitution time, pH, residual moisture, and potency. Residual moisture is a key attribute because excess water can reduce stability, while excessively low moisture may cause structural changes or aggregation in some systems. Stability studies compare real-time and accelerated conditions to estimate shelf life. Analytical methods must be validated for the specific matrix, container, and moisture range. Sterility and container integrity are also monitored for sterile products.
Handling practices aim to prevent moisture ingress and mechanical damage. Vials should remain stoppered and crimped until use, and reconstitution should follow the labeled diluent and volume. Shipping may involve temperature-controlled containers and desiccants, but direct contact between desiccant and product is avoided. Regulatory guidance expects documented storage conditions, excursion assessments, and stability commitments. Open questions remain about how best to predict long-term stability from short accelerated studies for every formulation class.
Freeze-drying is distinct from simple evaporation and from spray drying. Evaporation removes water at temperatures above freezing, while spray drying rapidly dries droplets in a heated gas stream. Lyophilization avoids high temperatures, which can be useful for heat-sensitive materials such as proteins, vaccines, and some foods. The porous cake produced by sublimation dissolves or rehydrates more quickly than a dense dried mass. Not all materials tolerate freezing or the pH shifts that can occur as solutes concentrate during ice formation.
Lyophilization removes water from a frozen material by sublimation under reduced pressure. The process begins with freezing, which converts liquid water into ice and fixes the structure of the sample. After freezing, primary drying lowers pressure so ice changes directly to vapor without passing through a liquid phase. Secondary drying then removes bound water that remains after ice sublimation. The result is a dry, porous solid that often retains its original shape.
| Property | Value | Notes |
|---|---|---|
| Typical appearance | White to off-white porous cake or powder | Color and structure vary with formulation. |
| Typical reconstitution time | Seconds to several minutes | Diluent, agitation, and temperature affect rate. |
| Typical storage temperature | 2–8 °C, 15–25 °C, or ≤−20 °C | Product-specific; protect from moisture and light. |
| Typical container closure | Glass vial with rubber stopper and crimp seal | Closure must limit moisture ingress. |
| Typical stability indicator | Residual moisture, potency, and reconstitution time | Monitored throughout shelf life. |
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.
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.
The physics of freeze-drying couples heat transfer, mass transfer, and phase change. Heat supplied through the shelf must reach the sublimation front without melting the ice or degrading the product. Water vapor then travels through the already dried layer and leaves the chamber, where low pressure and cold traps keep it from returning. The dried layer acts as a resistance to vapor flow, so drying rate changes as the front recedes. Open questions remain about how pore structure and formulation heterogeneity affect drying uniformity at larger scales.
Lyophilization removes water from a frozen material by sublimation under reduced pressure. The process begins with freezing, which converts liquid water into ice and concentrates dissolved solids. Primary drying then lowers chamber pressure so ice changes directly into vapor without passing through a liquid phase. Secondary drying raises the shelf temperature to remove bound water that remains after ice sublimation. The result is a dry, porous structure that can be reconstituted later.
Formulation composition influences whether freeze-drying produces an intact cake or a collapsed mass. Excipients such as sugars and polymers can raise the collapse temperature and provide bulk during drying. The critical temperature for primary drying is often the collapse temperature or the glass transition temperature of the maximally concentrated phase. If the product temperature exceeds this threshold, the frozen matrix may soften and lose structure. Established practice therefore links shelf temperature and chamber pressure to the formulation's thermal properties.
Quality control for freeze-dried forms includes visual inspection, water content measurement, and reconstitution time. A satisfactory cake is typically uniform, porous, and intact, although minor shrinkage or cracking may be acceptable if specifications allow. Karl Fischer titration, thermal gravimetric analysis, and near-infrared spectroscopy are used to measure water content. Reconstitution is assessed by adding a specified diluent and recording the time and ease of dissolution. Microbiological and particulate tests are added when the product is sterile or intended for injection.
Stability of a lyophilized solid depends on water content, temperature, and the physical state of the formulation. Amorphous products may slowly absorb moisture and drop below their glass transition temperature, causing collapse or crystallization. Some proteins and peptides can aggregate even in a dry state, especially when exposed to heat or moisture. Accelerated stability studies at elevated temperature and humidity help estimate shelf life, but real-time data remain the basis for expiration dating.
After drying, a lyophilized product is usually sealed under vacuum or an inert gas to limit moisture and oxygen exposure. The container closure system matters because stoppers and seals can allow moisture ingress over time. Storage conditions are selected from stability studies that track potency, cake appearance, and reconstitution behavior. Many freeze-dried materials are kept at controlled room temperature, while some require refrigeration or protection from light.
Patrick Pierre Sabatier, La pomme de terre, c'est aussi un produit diététique, Robert Laffont, 1993, 275 p. (ISBN 2-221-07631-1). Racines, tubercules, plantains et bananes dans la nutrition humaine, FAP, coll. « Nutrition », no 24, Rome, 1991 (ISBN 92-5-202862-5). Joël Robuchon et Patrick Sabatier, Le Meilleur et le Plus Simple de la pomme de terre, Robert Laffont, 1994, 250 p. (ISBN 2-253-08159-0).
Other additions to ColdFusion 8 are built-in Ajax widgets, file archive manipulation (CFZIP), Microsoft Exchange server integration (CFEXCHANGE), image manipulation including automatic CAPTCHA generation (CFIMAGE), multi-threading, per-application settings, Atom and RSS feeds, reporting enhancements, stronger encryption libraries, array and structure improvements, improved database interaction, extensive performance improvements, PDF manipulation and merging capabilities (CFPDF), interactive debugging, embedded database support with Apache Derby, and a more ECMAScript compliant CFSCRIPT. For development of ColdFusion applications, several tools are available: primarily Adobe Dreamweaver CS4, Macromedia HomeSite 5.x, CFEclipse, Eclipse and others. "Tag updaters" are available for these applications to update their support for the new ColdFusion 8 features.
=== Regulation of the 20S by the 19S === The 19S regulatory particle is responsible for stimulating the 20S to degrade proteins. A primary function of the 19S regulatory ATPases is to open the gate in the 20S that blocks the entry of substrates into the degradation chamber. The mechanism by which the proteasomal ATPase open this gate has been recently elucidated. 20S gate opening, and thus substrate degradation, requires the C-termini of the proteasomal ATPases, which contains a specific motif (i.e., HbYX motif). The ATPases C-termini bind into pockets in the top of the 20S, and tether the ATPase complex to the 20S proteolytic complex, thus joining the substrate unfolding equipment with the 20S degradation machinery. Binding of these C-termini into these 20S pockets by themselves stimulates opening of the gate in the 20S in much the same way that a "key-in-a-lock" opens a door. The precise mechanism by which this "key-in-a-lock" mechanism functions has been structurally elucidated in the context of human 26S proteasome at near-atomic resolution, suggesting that the insertion of five C-termini of ATPase subunits Rpt1/2/3/5/6 into the 20S surface pockets are required to fully open the 20S gate, confirming work previously done on yeast proteasome.
=== Social media and memes === On X (formerly Twitter), there are numerous accounts with names like "Socialists for Pritzker", "Nomadic Warriors for Pritzker", "Frat Bros for Pritzker", and "Anarchists for Pritzker". Socialists for Pritzker has over 13,000 followers. The accounts have been described as semi-ironic. Pritzker has said the attention is "entertaining, if a little strange" and that he keeps up with several of the accounts. Nomadic Warriors for Pritzker has dubbed Pritzker the "Great Khan of the Midwest" and mapped out battle plans for a Mongol Empire-inspired military campaign across the nation. The group of accounts, dubbed the "Pritzker Pals", launched a website, coconutbigboy.com, with the goal of influencing Vice President Kamala Harris to pick Pritzker as her running mate in the 2024 presidential election. A TikTok account called "Pritzker Memes" garnered 20,000 followers. Some of the memes relate to Pritzker's size, with one political commentator saying, "He is enormous, doesn't come off as particularly intellectual, and has good instincts". Pritzker launched his own beer brand, JBeers, ahead of the 2024 Democratic National Convention in Chicago. He also named Malört the DNC's "unofficial shot". On February 7, 2025, after President Trump announced that the Gulf of Mexico had been renamed the "Gulf of America", Pritzker posted a satirical video on his personal Twitter account announcing Illinois's annexation of Green Bay, Wisconsin, and the renaming of Lake Michigan to "Lake Illinois".
The Liberal Party grew out of the Whigs, who had their origins in an aristocratic faction in the reign of Charles II, and the early 19th century Radicals. The Whigs were in favour of reducing the power of the Crown and increasing the power of Parliament. Although their motives in this were originally to gain more power for themselves, the more idealistic Whigs gradually came to support an expansion of democracy for its own sake. The great figures of reformist Whiggery were Charles James Fox (died 1806) and his disciple and successor Earl Grey. After decades in opposition, the Whigs returned to power under Grey in 1830 and carried the First Reform Act in 1832. The Reform Act was the climax of Whiggism, but it also brought about the Whigs' demise. The admission of the middle classes to the franchise and to the House of Commons led eventually to the development of a systematic middle-class liberalism and the end of Whiggery, although for many years reforming aristocrats held senior positions in the party. In the years after Grey's retirement, the party was led first by Lord Melbourne, a fairly traditional Whig, and then by Lord John Russell, the son of a Duke but a crusading radical, and by Lord Palmerston, a renegade Irish Tory and essentially a conservative, although capable of radical gestures. As early as 1839, Russell had adopted the name of "Liberals"; in reality, his party was a loose coalition of Whigs in the House of Lords and Radicals in the Commons.
Sources: en.wikipedia.org
=== Post-settlement activity === In 1991, the local Bhopal authorities charged Anderson, who had retired in 1986, with manslaughter, a crime that carries a maximum penalty of 10 years in prison. He was declared a fugitive from justice by the Chief Judicial Magistrate of Bhopal on 1 February 1992 for failing to appear at the court hearings in a culpable homicide case in which he was named the chief defendant. Orders were passed to the Government of India to press for an extradition from the United States. The United States declined to extradite him citing a lack of evidence. The U.S. Supreme Court refused to hear an appeal of the decision of the lower federal courts in October 1993 against allowing victims of the Bhopal disaster to seek damages in a U.S. court. In 2004, the Indian Supreme Court ordered the Indian government to release any remaining settlement funds to victims. And in September 2006, the Welfare Commission for Bhopal Gas Victims announced that all original compensation claims and revised petitions had been "cleared". In 2006, the U.S. Court of Appeals for the Second Circuit in New York City upheld the dismissal of remaining claims in the case of Bano v. Union Carbide Corporation. This move blocked plaintiffs' motions for class certification and claims for property damages and remediation.
== Chemistry == THC is a molecule that combines polyketides (derived from acetyl CoA) and terpenoids (derived from isoprenylpyrophosphate). It is hydrophobic with very low solubility in water, but good solubility in many organic solvents. As a phytochemical, THC is assumed to be involved in the plant's evolutionary adaptation against insect predation, ultraviolet light, and environmental stress.
=== Apodization in mass spectrometry === During oscillation within an Orbitrap, a transient signal may not be stable until the ions settle into their oscillations. Toward the end, subtle ion collisions add up to cause noticeable dephasing. This presents a problem for the Fourier transform, as it averages the oscillatory signal across the length of the time-domain measurement. Software allows "apodization", the removal of the front and back section of the transient signal from consideration in the FT calculation. Thus, apodization improves the resolution of the resulting mass spectrum. Another way to improve the quality of the transient is to wait to collect data until ions have settled into stable oscillatory motion within the trap.
== Medical uses == When used in low doses, corticosteroids serve as an anti-inflammatory agent. At higher doses, they are considered as immunosuppressants. Corticosteroids inhibit the inflammatory response to a variety of inciting agents and, it is presumed, delay or slow healing. They inhibit edema, fibrin deposition, capillary dilation, leukocyte migration, capillary proliferation, fibroblast proliferation, deposition of collagen, and scar formation associated with inflammation.
== Deaths == 1 January – Frank McGarvey, Scottish footballer (St Mirren, Celtic, national team) (b. 1956) 18 March – Robert Lindsay, 29th Earl of Crawford, Scottish peer, MP (1955–1974) and Minister of State for Defence (1970–1972) (b. 1927) 21 March Willie Bell, Scottish footballer (Leeds United, national team) and manager (Birmingham City) (b. 1937) John Smith, Baron Kirkhill, Scottish peer, Lord Provost of Aberdeen (1971–1975) and Minister of State for Scotland (1975–1978) (b. 1930) 1 April – Ken Buchanan, professional boxer who became undisputed world lightweight champion in 1971 (b. 1945) 8 April – Bob Heatlie, Scottish songwriter ("Japanese Boy", "Cry Just a Little Bit", "Merry Christmas Everyone") and record producer (b. 1946). 30 April – Elizabeth Scott, Duchess of Buccleuch, wife of Richard Scott, 10th Duke of Buccleuch (b. 1954) 10 May – Hugo Burge, internet entrepreneur and owner of Marchmont House (b. 1972) 15 June – Gordon McQueen, Scottish footballer (Leeds United, Manchester United, national team) and manager. (b. 1953) 21 June – Winnie Ewing, Scottish politician (MP (1967–1979), MEP (1979–1999), MSP (1999–2003), President of the Scottish National Party (1987–2005)) (b. 1929) 26 June Craig Brown, Scottish professional footballer and football manager. (b. 1940) David Ogilvy, 13th Earl of Airlie, Scottish peer and Lord Chamberlain (1984–1997) (b. 1926) 2 July – Greig Oliver, 58, rugby union player. 6 September – John Cairney, Scottish actor (A Night to Remember, Cleopatra, Jason and the Argonauts), author and painter. (b.
Sources: en.wikipedia.org
== Tributes == "Referring to the death of Professor Brailsford Robertson yesterday, the Prime Minister (Mr. Scullin) said:— His untimely end has robbed Australia of a brilliant scientist, whose contribution to the Commonwealth's progress would always be remembered. On behalf of the Federal Ministry Mr. Scullin extended his sincere sympathy to Professor Robertson's family, and expressed its appreciation of the great national services which he had rendered." The Argus, 20 January 1930. "Professor Brailsford Robertson was one of Australia's most brilliant scientists. The value of the work he was accomplishing cannot be estimated." Hon. R.L. Butler, Premier of South Australia, 20 January 1930. "The main purpose of [Robertson's] studies was to solve the mystery of physical life in it successive stages of commencement, growth, decline, and cessation, for the benefit of his fellow-men. ... The amount of original work he accomplished in his short life was prodigious. I would be rash to assert that the loss to science, or as I should prefer to say, the loss to humanity, caused by his death is irreparable, but it will probably be a long time before anyone else is able to gather the threads together and produce the fabric he was attempting to weave on his loom." Sir George Murray, Chancellor of the University of Adelaide, 18 March 1932.
Before recording, Parsons and Harris played a preliminary four-show mini-tour as the headline act in a June 1973 Warner Bros. Records country rock package with the New Kentucky Colonels and Country Gazette. A shared backing band included Clarence White, Pete Kleinow and Chris Ethridge. On July 15, 1973, White was killed by a drunk driver in Palmdale, California, while loading equipment in his car for a concert with the New Kentucky Colonels. At White's funeral, Parsons and Bernie Leadon performed a rendition of "Farther Along"; that evening, Parsons reportedly informed Phil Kaufman of his final wish: to be cremated in Joshua Tree National Monument.
== Etymology == The name mercapturic acid is a combination of mercapturic and acid. The latter indicates that the compound is an acid. The former is a compound word consisting of the stem mercaptur-, coming from mercaptan, and the suffix -ic, meaning "having the character of". In sum, the name mercapturic acid means "an acid with mercaptan character/nature".
=== Herbal supplements === Some herbal supplements, including valerian, kava, chamomile, lavender, passion flower, and hops among others, are purported to have hypnotic effects and are used to treat sleeping problems, but little to no clinical data are available to support their use.
== Isotope vs. nuclide == A nuclide is a species of an atom with a specific number of protons and neutrons in the nucleus, for example, carbon-13 with 6 protons and 7 neutrons. Thus the terms are roughly the same, but the nuclide concept (referring to individual nuclear species) emphasizes nuclear properties over chemical properties, whereas the isotope concept (grouping all atoms of each element) emphasizes chemical over nuclear. The neutron number greatly affects nuclear properties, but its effect on chemical properties is negligible for most elements. Even for the lightest elements, whose ratio of neutron number to atomic number varies the most between isotopes, it usually has only a small effect although it matters in some circumstances (for hydrogen, the lightest element, the isotope effect is large enough to affect biology strongly). The term isotopes (originally also isotopic elements, now sometimes isotopic nuclides) is intended to imply comparison (like synonyms or isomers). For example, the nuclides 126C, 136C, 146C are isotopes (nuclides with the same atomic number but different mass numbers), but 4018Ar, 4019K, 4020Ca are isobars (nuclides with the same mass number). As the older and better-known term, isotope is however still used in some contexts where nuclide might be more appropriate, such as in nuclear technology and nuclear medicine.
Sources: en.wikipedia.org
Collapse occurs when the product temperature rises above its collapse or eutectic temperature during drying. The frozen matrix loses structure, producing a shrunken or melted appearance. This can slow reconstitution and may affect stability.
Karl Fischer titration is a common method, along with loss on drying and thermogravimetric analysis. Each method has different sensitivity and sample requirements. Results should be interpreted with the product's formulation and container in mind.
No. Lyophilization removes water but is not a sterilization step. Sterile products are typically filtered and filled aseptically before freezing, and container closure integrity is maintained afterward.
Lyophilization relies on sublimation, so water moves from solid ice to vapor without becoming liquid. The material is frozen, pressure is reduced, and controlled heat is supplied. Vapor is captured on a cold condenser, leaving a dry porous solid.