A practical reference on sublimation: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
Lyophilization is a drying process in which a solvent, usually water, is removed from a frozen material by sublimation under reduced pressure. The material is first solidified, then placed under vacuum so that ice transitions directly to vapor without a bulk liquid phase. This approach suits heat-sensitive substances that would degrade during conventional evaporation. Primary drying removes unbound ice, while secondary drying reduces water that remains adsorbed to the solid matrix. The result is a porous, lightweight solid that can be reconstituted later.
A typical cycle begins with freezing, sometimes including an annealing step to control ice crystal size. Freezing conditions influence the pore network that later allows vapor escape. During primary drying, shelf temperature and chamber pressure are set so heat enters the product while its temperature stays below the collapse or eutectic point. Secondary drying then raises the shelf temperature to desorb bound water and lower residual moisture. Cycle design depends on formulation, fill volume, container type, and equipment capability.
The physics of lyophilization couples heat transfer, mass transfer, and phase behavior. Sublimation requires a vapor pressure difference between the ice front and the chamber, and the dried layer adds resistance to vapor flow. Amorphous formulations are characterized by a glass transition temperature of the maximally freeze-concentrated solute, often denoted Tg'. Crystalline bulking agents can provide structure, while amorphous excipients stabilize labile components. Open questions remain about spatial heterogeneity, edge effects, and how laboratory cycles scale to production.
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.
| Property | Value | Notes |
|---|---|---|
| Physical state | Solid, porous cake or powder | Depends on formulation and container |
| Typical storage temperature | 2–25 °C, protected from moisture | Some materials require colder conditions |
| Solubility class | Usually readily soluble after reconstitution | Not an intrinsic chemical property |
| Common analytical method | Karl Fischer titration | Used for residual moisture |
| Common synonyms | Freeze-drying; lyophilisation | Lyophilisation is a spelling variant |
Industries use lyophilization for pharmaceuticals, biological products, and food preservation. In the pharmaceutical sector, it extends the shelf life of injectable drugs, vaccines, and proteins that are unstable in aqueous solution. Food manufacturers apply freeze-drying to coffee, fruits, and ready meals to retain flavor and texture. The process is energy-intensive and requires specialized equipment, which limits its use to high-value products. Ongoing research examines how formulation and process parameters affect the quality of the final dried product.
Lyophilization, also known as freeze-drying, is a process that removes water from a material by freezing it and then reducing pressure to allow ice to sublimate directly into vapor. The method begins with a freezing step that solidifies the water content. Next, primary drying lowers the pressure below the triple point of water, enabling sublimation without passing through a liquid phase. A final secondary drying step removes bound water through desorption. This sequence produces a dry, porous cake that can be reconstituted later.
The process relies on the phase diagram of water, where the triple point marks the conditions at which ice, liquid water, and vapor coexist. By maintaining pressure below this point, typically around 0.01 to 0.1 millibar, sublimation becomes the dominant mechanism. Formulations often include excipients such as sugars or polymers that act as lyoprotectants and bulking agents. These additives help preserve the structure of the active ingredient and prevent collapse during drying. The choice of excipient and freezing rate influences the final cake morphology and stability.
Quality control for lyophilized materials includes visual inspection, residual moisture measurement, and reconstitution testing. Cake appearance can reveal process problems such as collapse, shrinkage, or meltback, although appearance alone does not prove potency. Residual moisture is commonly measured by Karl Fischer titration or by loss on drying. Reconstitution time is checked because a slow or incomplete dissolve can indicate a change in pore structure. Stability studies track these attributes over time under defined temperature and humidity conditions.
Analytical methods for lyophilized solids must account for the low moisture content and the fragile cake. Karl Fischer titration is widely used for water content, while near-infrared spectroscopy can measure moisture non-destructively in sealed containers. X-ray diffraction and modulated differential scanning calorimetry help identify crystalline or amorphous phases. Residual solvent analysis may be needed if organic solvents were used during formulation. The combination of these methods supports batch release and long-term stability assessment.
A formulation often contains excipients that protect the active ingredient during freezing and drying. Bulking agents provide structure, while lyoprotectants stabilize sensitive molecules. The freezing step can produce ice crystals whose size and distribution affect the drying rate, and cycle design includes freezing, annealing, and drying phases. If the product temperature rises above a critical value, the cake may collapse or lose its porous structure. Successful lyophilization therefore depends on the interaction between formulation, equipment, and cycle design.
Lyophilization is a dehydration process that removes water from a frozen material by sublimation under low pressure. The material is first frozen to convert liquid water into ice. Next, the pressure is reduced below the triple point of water so that ice changes directly into vapor without passing through a liquid phase. This step is called primary drying. The result is a porous solid or cake that retains the original shape of the frozen solution.
Liberal Democrat History Group. Catalogue of the Liberal Party papers (mostly dating from after 1945) at LSE Archives. The Liberal Magazine Volume 2 1895. Liberal Magazine A Periodical for the Use of Liberal Speakers, Writers and Canvassers Volume 1 1893. Facts for Liberal Politicians By John Noble 1879. Proceedings in Connection with the Annual Meeting of the National Liberal Federation with the Annual Report By National Liberal Federation, 1881. Election Address and Speeches By Samuel Smith, 1882. Annual Report Presented at a Meeting of the Council By National Liberal Federation, 1887. Proceedings of the Annual Meeting of the Council By National Liberal Federation, 1895. Five Years of Liberal Policy and Conservative Opposition By George Charles Brodrick, 1874. Leaflets By National Liberal Federation, 1898. Pamphlets and Leaflets of the Liberal Publication Dept By Liberal Publication Department (Great Britain), 1900. The Liberal Magazine Volume 7, Publisher: Liberal Publication Department, 1900. Leaflets published by the Liberal Publication Department for the General Election of 1906, 1906. The Liberal year book for 1908. The Government's record, 1906–1913 : seven years of Liberal legislation and administration By Liberal Publication Dept. (Great Britain). The Yale Review Volume 4 1895. The Age of Lloyd George The Liberal Party and British Politics, 1890–1929 By Kenneth O. Morgan, 2021.
Substances found, according to the reports, are 1-Naphthol, naphthalene, Sevin, tarry residues, organochlorines, mercury, chromium, copper, nickel, lead, hexachlorethane, hexachlorobutadiene, pesticide HCH, volatile organic compounds and halo-organics. Many of these contaminants were also found in breast milk of women living near the area. Soil tests were conducted by Greenpeace in 1999. One sample (IT9012) from "sediment collected from drain under former Sevin plant" showed mercury levels to be at "20,000 and 6 million times" higher than expected levels. Organochlorine compounds at elevated levels were also present in groundwater collected from (sample IT9040) a 4.4 metres (14 ft) depth "bore-hole within the former UCIL site". This sample was obtained from a source posted with a warning sign which read "Water unfit for consumption". Chemicals that have been linked to various forms of cancer were also discovered, as well as trichloroethylene, known to impair foetal development, at 50 times above safety limits specified by the U.S. Environmental Protection Agency (EPA). In 2002, an inquiry by Fact-Finding Mission on Bhopal found a number of toxins, including mercury, lead, 1,3,5 trichlorobenzene, dichloromethane and chloroform, in nursing women's breast milk. A 2004 BBC Radio 5 broadcast reported the site is contaminated with toxic chemicals including hexachlorocyclohexane and mercury, held in open containers or loose on the ground.
== Ribozyme based origin of sexual reproduction == Sexual reproduction might have been present in the RNA world that preceded DNA cellular life forms. Early cellular life forms having genomes with single copies of essential RNA ribozyme molecules would likely have been vulnerable to environmental damaging conditions that could block replication of an essential ribozyme thus causing cell death. Merger of two such damaged early cells (sexual interaction) would allow undamaged combinations of RNA segments to come together, thus facilitating formation of a functional genome and allowing survival of the cell and ability to reproduce.
Applebaum's introduction has been criticized by Gulag researcher Wilson Bell, stating that her book "is, aside from the introduction, a well-done overview of the Gulag, but it did not offer an interpretative framework much beyond Solzhenitsyn's paradigms".
Sources: en.wikipedia.org
Eli Lilly and Company, doing business as Lilly, is an American multinational pharmaceutical company headquartered in Indianapolis, Indiana, with offices in 18 countries. Its products are sold in approximately 125 countries. The company was founded in 1876 by Eli Lilly, a pharmaceutical chemist and Union army veteran during the American Civil War for whom the company was later named. The company is ranked 4th on the list of largest biomedical companies by revenue and is the most valuable pharmaceutical company worldwide. It is ranked 100th on the Fortune 500 and 138th on the Forbes Global 2000. In November 2025, the company reached a $1 trillion market capitalization, the first health-care company in the world to do so. The company's primary products are tirzepatide (Mounjaro and Zepbound) for the treatment of type 2 diabetes, weight loss, and obstructive sleep apnea (56% of 2025 revenues); abemaciclib (Verzenio) for the treatment of advanced or metastatic breast cancers (9% of 2025 revenues); dulaglutide (Trulicity) for the treatment of type 2 diabetes (7% of 2025 revenues); ixekizumab (Taltz) for the treatment of autoimmune diseases (6% of 2025 revenues); and empagliflozin (Jardiance) for the treatment of type 2 diabetes (5% of 2025 revenues).
=== Stress === Stress, to a physiologist, means any situation that threatens the continued stability of the body and its functions. Stress affects a wide variety of body systems: the two most consistently activated are the hypothalamic-pituitary-adrenal axis and the norepinephrine system, including both the sympathetic nervous system and the locus coeruleus-centered system in the brain. Stressors of many types evoke increases in noradrenergic activity, which mobilizes the brain and body to meet the threat. Chronic stress, if continued for a long time, can damage many parts of the body. A significant part of the damage is due to the effects of sustained norepinephrine release, because of norepinephrine's general function of directing resources away from maintenance, regeneration, and reproduction, and toward systems that are required for active movement. The consequences can include slowing of growth (in children), sleeplessness, loss of libido, gastrointestinal problems, impaired disease resistance, slower rates of injury healing, depression, and increased vulnerability to addiction.
== Toxicity to animals == Minoxidil is highly toxic to dogs and cats, even in doses as small as a drop or lick. There are reported cases of cats dying shortly after coming in contact with minimal amounts of the substance. There is no specific antidote, but lipid rescue has been used successfully.
Coenzyme Q (CoQ) is a quinone and an electron carrier in the mitochondrial electron transport chain (ETC) of eukaryotes and many bacteria. The other name for CoQ is ubiquinone which was assigned by the IUPAC-IUB Commission on Biochemical Nomenclature in 1975 due to its ubiquitous presence from bacteria to humans. In humans the isoprene side chain has ten isoprene units, hence the abbreviation CoQ10. Coenzyme Q is a coenzyme family that is ubiquitous in animals and many Pseudomonadota, a group of gram-negative bacteria. The fact that the coenzyme is ubiquitous gives the origin of its other name, ubiquinone. In humans, the most common form of coenzyme Q is coenzyme Q10, also called CoQ10 () or ubiquinone-10. Coenzyme Q10 is a 1,4-benzoquinone, in which "Q" refers to the quinone chemical group and "10" refers to the number of isoprenyl chemical subunits (shown enclosed in brackets in the diagram) in its tail. In natural ubiquinones, there are from six to ten subunits in the tail, with humans having a tail of 10 isoprene units (50 carbon atoms) connected to its benzoquinone "head". This family of fat-soluble substances is present in all respiring eukaryotic cells, primarily in the mitochondria. Ninety-five percent of the human body's energy is generated this way. Organs with the highest energy requirements—such as the heart, liver, and kidney—have the highest CoQ10 concentrations. There are three redox states of CoQ: fully oxidized (ubiquinone), semiquinone (ubisemiquinone), and fully reduced (ubiquinol).
In October 2020, Nick Tarabay joined the cast as a series regular as Eclipso while Jonathan Cake was cast as Shade and Ysa Penarejo was cast in an undisclosed role in recurring capacities for the second season (later revealed to be Jennifer-Lynn Hayden / Jade, the daughter of Green Lantern), while Jim Gaffigan was cast as the voice of Thunderbolt. The following month, Alkoya Brunson was cast in a recurring role as Jakeem Thunder. In February 2021, John Wesley Shipp was revealed to be reprising his role as Jay Garrick from The Flash, albeit as an alternate version. Alex Collins replaced Thomas as Doctor Mid-Nite for the second season. Hopkins and Osmanski were promoted to series regulars for the third season in August 2021, following their recurring roles in the first season and guest appearance in the second. McHale was also promoted to a series regular in October for the third season following his guest appearances in the first two seasons. In March 2022, Tim Gabriel was cast as Todd Rice / Obsidian. In May, Seth Green joined the cast in recasting to succeed Gaffigan who voiced Thunderbolt last season. The third season trailer confirmed the return of Eric Goins as Steven Sharpe / Gambler, who appeared in the first but was absent from the second.
Sources: en.wikipedia.org
Eucalyptus globulus subsp. bicostata (Maiden, Blakely & Simmonds) J.B.Kirkp. (formerly Eucalyptus bicostata), commonly known as Victorian blue gum or eurabbie, has sessile flower buds arranged in groups of three; Eucalyptus globulus Labill. subsp. globulus, commonly known as Tasmanian blue gum, has flower buds arranged singly in leaf axils; Eucalyptus globulus subsp. maidenii (F.Muell.) J.B.Kirkp. (formerly Eucalyptus maidenii), commonly known as Maiden's gum has flower buds arranged in groups of seven Eucalyptus globulus subsp. pseudoglobulus (Naudin) J.B.Kirkp. (formerly Eucalyptus globulus var. pseudoglobulus), commonly known as Victorian eurabbie has pedicellate flower buds arranged in groups of three.
=== Thyroid inhibition === Perchlorate is a potent competitive inhibitor of the thyroid sodium-iodide symporter. Thus, it has been used to treat hyperthyroidism since the 1950s. At very high doses (70,000–300,000 ppb) the administration of potassium perchlorate was considered the standard of care in the United States, and remains the approved pharmacologic intervention for many countries. In large amounts perchlorate interferes with iodine uptake into the thyroid gland. In adults, the thyroid gland helps regulate the metabolism by releasing hormones, while in children, the thyroid helps in proper development. The NAS, in its 2005 report, Health Implications of Perchlorate Ingestion, emphasized that this effect, also known as Iodide Uptake Inhibition (IUI) is not an adverse health effect. However, in January 2008, California's Department of Toxic Substances Control stated that perchlorate is becoming a serious threat to human health and water resources. In 2010, the EPA's Office of the Inspector General determined that the agency's own perchlorate reference dose (RfD) of 24.5 parts per billion protects against all human biological effects from exposure, as the federal government is responsible for all US military base groundwater contamination. This finding was due to a significant shift in policy at the EPA in basing its risk assessment on non-adverse effects such as IUI instead of adverse effects.
Carbohydrates are compounds made up of types of sugar. Carbohydrates are classified according to their number of sugar units: monosaccharides (such as glucose and fructose), disaccharides (such as sucrose and lactose), oligosaccharides, and polysaccharides (such as starch, glycogen, and cellulose). Proteins are organic compounds that consist of amino acids joined by peptide bonds. Since the body cannot manufacture some of the amino acids (termed essential amino acids), the diet must supply them. Through digestion, proteins are broken down by proteases back into free amino acids. Fats consist of a glycerin molecule with three fatty acids attached. Fatty acid molecules contain a -COOH group attached to unbranched hydrocarbon chains connected by single bonds alone (saturated fatty acids) or by both double and single bonds (unsaturated fatty acids). Fats are needed for construction and maintenance of cell membranes, to maintain a stable body temperature, and to sustain the health of skin and hair. Because the body does not manufacture certain fatty acids (termed essential fatty acids), they must be obtained through one's diet.
=== In television === "Cancelled", an episode of the animated sitcom South Park Series 2 of COBRA, a British thriller series, revolves around a sustained campaign of cyberwar against the United Kingdom and the British government's response to it.
Sources: en.wikipedia.org
Freezing only converts liquid to solid. Lyophilization adds vacuum and controlled warming so frozen solvent sublimes, leaving a dry porous solid. The two steps are related but not interchangeable.
Reduced pressure keeps the solvent below its triple point, allowing ice to become vapor without melting. Vacuum also helps remove water vapor from the product chamber. The exact pressure is chosen with the formulation and equipment.
Residual moisture is water that remains in the dried solid after secondary drying. It is often measured by Karl Fischer titration, near-infrared spectroscopy, or thermogravimetry. Acceptable levels depend on the material and its stability profile.
Sealed vials or containers should be kept at the temperature specified by stability data, often controlled room temperature or 2–8 °C. Moisture and oxygen barriers are important because both can degrade sensitive materials. Opened containers may need immediate use or protection from ambient humidity.