This is a working overview of sublimation, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-05-27. Anything still debated is marked as such rather than presented as settled.
Quality control for freeze-dried lots combines visual inspection with instrumental tests. Cake appearance, color, and shrinkage are recorded against a reference, while residual moisture is measured by Karl Fischer titration or loss on drying. Thermal analysis can reveal phase transitions and crystallization events, and X-ray diffraction distinguishes amorphous from crystalline solids. Microbiological tests and container closure integrity checks are also routine for sterile products. Analytical methods must be validated for the matrix, because excipients and low moisture can affect accuracy. Open questions include how best to predict long-term stability from short-term data.
Lyophilized solids are often hygroscopic, so handling occurs in controlled low-humidity areas or glove boxes when the material is exposed. Vials remain sealed with elastomeric stoppers and aluminum crimps until use, because airborne moisture can raise residual water and shorten shelf life. The porous cake is fragile and may crack, shrink, or powder during transport. Personnel typically avoid repeated warming and cooling of sealed units, which can draw moisture through closures. These practices aim to preserve the low water content achieved during drying.
Storage conditions depend on the formulation and the intended shelf life. Many pharmaceutical and biological freeze-dried products are kept at 2–8 °C, while some stable foods and reagents tolerate room temperature. Others require −20 °C or colder to slow chemical degradation or aggregation. Protection from light and oxygen is common because oxidation can continue in the dry state. Stability studies usually monitor potency, appearance, moisture, and reconstitution time over months or years. Predictions from accelerated studies are useful but may not fully capture real-time changes.
A typical cycle begins with freezing, which fixes the material into a solid and determines ice crystal size. Primary drying then raises heat under vacuum so ice sublimes, often near or below the collapse temperature of the formulation. Secondary drying removes bound water that remains after ice is gone, usually by gently warming the product. Each stage balances heat input against pressure to avoid melting or structural damage. Temperature probes and pressure sensors guide the transition between stages.
In practice, lyophilization is slower and more energy intensive than simple drying. Cycle times can range from hours to several days depending on load, container, and formulation. Amorphous materials may require excipients that help preserve structure during freezing and drying. The method is widely used for biological materials, pharmaceuticals, and foods where heat drying would cause unacceptable change. Open questions remain about scaling cycles between laboratory and production equipment, and this gap affects technology transfer.
| Property | Value | Notes |
|---|---|---|
| Typical storage temperature | 2–8 °C | Some products tolerate room temperature or require −20 °C. |
| Residual moisture method | Karl Fischer titration | Coulometric or volumetric; specific for water. |
| Cake appearance | Uniform porous plug | Collapse, shrinkage, or meltback indicates process deviation. |
| Reconstitution time | Seconds to several minutes | Depends on cake porosity, diluent, and formulation. |
| Primary container | Glass vial with elastomeric stopper | Crimp seal limits moisture ingress. |
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.
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.
Mondobiotech (styled mondoBIOTECH) was a Swiss biotechnology company focused on identifying potential treatments for rare diseases. Founded in 2001, it developed drug candidates by examining existing research on human peptides and other biological substances, and sought partners to conduct further development and licensing. Its holding company listed shares on the SIX Swiss Exchange in 2009. The holding company changed its name to THERAMetrics in 2013 and completed a combination with Pierrel Research International later that year; following a further business combination, it became Relief Therapeutics Holding AG in 2016.
Specific site targeting requires the residues to also be modified to be accessible and chemically bioorthogonal to the rest of the silk protein. Cytosine residues are commonly used for this type of conjugation through a Michael addition, but they tend to undergo exchange reactions which makes them unstable for long durations in a biological environment. These two methods are rather outdated but have been useful in validating the fact that 4RepCT can be tuned in the important areas of cellular adhesion, antimicrobial potency, and the type of molecule or drug attached to it. Later azide functional groups were conjugated to the N-terminal of a dragline silk protein using EDC/NHS coupling, yielding glycopolymer-conjugated films with enhanced cell adhesion and DNA-silk chimeras with controllable micro-architectures. Armed with this, the researchers in this study investigated the incorporation of 3 L-Aha residues into 4RepCT, yielding
DrugPedia is a wiki created for collecting and compiling information related to computer-aided drug design. It is developed under the umbrella of the OSDD project and covers a wide range of subjects around drugs like bioinformatics, cheminformatics, clinical informatics etc. Indipedia: A wiki for collecting and compiling drug information related to India. It is intended is to provide comprehensive information about India created for Indians by Indians. It is developed under the umbrella of the OSDD project. The CRDD Forum was launched to discuss the challenges in developing computational resources for drug discovery.
=== World War I and aftermath === During World War I, what later became known as the Sudetenland experienced a rate of war deaths that was higher than most other German-speaking areas of Austria-Hungary and exceeded only by German South Moravia and Carinthia. Thirty-four of each 1,000 inhabitants were killed. Austria-Hungary broke apart at the end of World War I. In late October 1918, an independent Czechoslovak state, consisting of the lands of the Bohemian kingdom and areas belonging to the Kingdom of Hungary, was proclaimed. The German deputies of Bohemia, Moravia, and Silesia in the Imperial Council (Reichsrat) referred to the Fourteen Points of US President Woodrow Wilson and the right proposed therein to self-determination and attempted to negotiate the union of the German-speaking territories with the new Republic of German Austria, which itself aimed at joining Weimar Germany. The German-speaking parts of the former Lands of the Bohemian Crown were to be part of a newly created Czechoslovakia, a multi-ethnic state of several nations: Czechs, Germans, Slovaks, Hungarians, Poles and Ruthenians. On 20 September 1918, the Prague government asked for the opinion of the United States on the Sudetenland. Wilson sent Ambassador Archibald Coolidge into Czechoslovakia. Coolidge insisted on respecting the Germans' right to self-determination and uniting all German-speaking areas with either Germany or Austria, with the exception of northern Bohemia. However, the American delegation at the Paris talks decided not to follow Coolidge's proposal.
Sources: en.wikipedia.org
== Career == After graduating from Ohio State University in 1938, Minnich wrote to Carl Moore to ask for a job and he offered her a position as a research technician helping start a Hematology department at Washington University. She remained at Washington University for her entire career. She was promoted to a research associate in 1954, research assistant professor in 1958, research associate professor in 1963, and full professor of Medicine in 1974 (the first person without a doctorate degree to reach this rank at Washington University). She became professor emeritus in 1978 and retired in 1984. She also worked at Barnes Hospital in St. Louis from 1975 to the mid-1980s as assistant and then associate director of Hematology. She was regarded as an excellent teacher and, in addition to her official teaching responsibilities, she gave informal "night courses" to pathologists, lab technicians, and others. She created a series of audiovisual teaching materials describing the morphology of blood and bone marrow that were published by the American Society of Clinical Pathologists in the early 1980s as a 10-part course in morphologic hematology.
==== Australia ==== Mescaline is considered a schedule 9 substance in Australia under the Poisons Standard (February 2020). A schedule 9 substance is classified as "Substances with a high potential for causing harm at low exposure and which require special precautions during manufacture, handling or use. These poisons should be available only to specialised or authorised users who have the skills necessary to handle them safely. Special regulations restricting their availability, possession, storage or use may apply."
Both lancelets and lampreys have a primitive but functional interferon system that responds to their versions of interferons by upregulating gene similar to the well-known interferon-stimulated genes (LSGs) of land animals. The lamprey interferon receptor has also been identified as a heterodimer of the cytokine receptor family B (CRFB) family, much like in jawed vertebrates. By comparing the genome organizations of jawed fish, jawless fish, and lancelet, it was found that interferons arose by a duplication of interleukin 10 in a chordate ancestor to the vertebrates and the lancelets. By the time the bony fish (e.g. teleosts, tetrapods including humans) diverged from the cartilaginous fish (e.g. sharks), the duplication and specialization of interferon into types I, II (gamma), III (lambda), and IV had been complete. (This is known because types I, II, IV have been found in tetrapods, teleosts, and sharks, and that type III has been found in tetrapods and sharks.) Mammals, actually amniotes in general, are unlike the rest of the animal kingdom in that most of their type I IFNs are intronless, and are placed in a position not colinear with the other vertebrates. This is because the original type I IFN gene was copied in an intronless form (possibly by a retrotransposon acting on mRNA) to a new location between HACD4 and MTAP in a common ancestor of the amniotes, followed by a loss of the ancestral version.
Sources: en.wikipedia.org
In 1960, the protagonist, Jack, is a passenger on a plane that crashes in the Atlantic Ocean. The only survivor, Jack makes his way to a nearby lighthouse; inside is a bathysphere that takes him to Rapture. Jack is contacted via radio by Atlas, who helps guide him through the ruined city. Atlas requests Jack's help in saving his family, who he says are in a docked bathysphere. When Jack first encounters the Little Sisters, Atlas urges him to kill them to harvest their ADAM. Dr. Brigid Tenenbaum intervenes and insists Jack should spare them, providing him with a plasmid that can remove the sea slug from their bodies and free them of their brainwashing. Jack works his way to the bathysphere, but Ryan destroys it before Jack can reach it. Infuriated, Atlas has Jack fight his way through various districts toward Ryan's lair, forcing Jack to contend with Rapture's deranged citizens along the way, such as the surgical doctor J.S. Steinman and artist and musician Sander Cohen. Jack enters Ryan's office. Ryan reveals the truth of Jack's origins: he is Ryan's illegitimate son, sold by Ryan's mistress as an embryo to Fontaine, who had Tenenbaum and Suchong rapidly age Jack into adulthood and turned into an obedient assassin, capable of accessing any of Rapture's systems locked to Ryan's genetic code and thus ensure Fontaine's victory in the war. Jack was smuggled to the surface with false memories of a normal life, waiting to be called back to Rapture when needed.
Although these are both aspects of earthworm activities the net effect is important to ascertain, in particular in the frame of organic matter disappearance linked to global warming. It seems that there is now a consensus about the prominent role of earthworms in carbon sequestration due to the fact that part of organic matter is mineralized at or near the soil surface while the major part is incorporated in the deep soil where it is stabilized by links with clay minerals.
Many jurisdictions require operators be certified or licensed to work with chainsaws. Injury can also result if the chain breaks during operation due to poor maintenance or attempting to cut inappropriate materials. Gasoline-powered chainsaws expose operators to harmful carbon monoxide gas, especially indoors or in partially enclosed outdoor areas. Drop starting, or turning on a chainsaw by dropping it with one hand while pulling the starting cord with the other, is a safety violation in most states in the U.S. Keeping both hands on the saw for stability is essential for safe chainsaw use. Safe and effective chainsaw and crosscut use on federally administered public lands within the United States has been codified since 2016 in the Final Directive for National Saw Program issued by the United States Forest Service, which specifies the training, testing, and certification process for employees and unpaid volunteers who operate chainsaws within public lands.
Sources: en.wikipedia.org
Karl Fischer titration is widely used because it is specific for water and works at low levels. Loss on drying is simpler but less specific, since volatile solvents or decomposition products can also be lost.
Collapse can occur when the product temperature exceeds its critical formulation temperature during drying. The porous structure then melts or shrinks, reducing reconstitution speed and sometimes altering stability.
No. Low moisture slows many degradation pathways but does not stop oxidation, hydrolysis, or physical changes completely. Storage temperature, container closure, and formulation still influence shelf life.
Primary drying removes ice by sublimation under vacuum. Secondary drying removes water that is bound to the material, often by warming the product after most ice has left. Both stages occur below temperatures that would cause unwanted melting.