The short version of Karl Fischer fits in a sentence. The long version — which is the one that helps — is below.
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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.
After lyophilization, the product is usually a porous cake or powder with a large internal surface area. This structure can absorb moisture quickly if exposed to humid air, so vials are sealed under vacuum or an inert gas. Moisture uptake may lower the glass transition temperature of the dried matrix and accelerate chemical or physical degradation. Storage conditions therefore depend on the formulation, container, and intended shelf life. Some products remain stable at room temperature, while others require refrigeration or freezing.
The process generally proceeds in three stages: freezing, primary drying, and secondary drying. During freezing, controlled cooling converts water into ice and may also crystallize or vitrify solutes. In primary drying, the pressure is lowered below the triple point, and heat is supplied so ice sublimes directly to vapor. Secondary drying removes water that remains bound to the solid matrix, yielding a low final water content. Product temperature must stay below the collapse or glass transition temperature to maintain structure. Cycle design therefore balances shelf temperature, chamber pressure, and time.
Freeze-drying is used for materials whose activity or structure depends on low temperature and low water content. Examples include certain biologics, diagnostic reagents, starter cultures, coffee, and porous inorganic precursors. The dried product forms a cake whose porosity aids rapid wetting and dissolution. Main drawbacks are high energy use, long cycle times, and sensitivity to formulation and equipment variation. Questions remain about how freezing rates and ice morphology affect batch uniformity, especially when moving from laboratory to production scale.
Lyophilization, also called freeze-drying, is a dehydration process in which a solvent, usually water, is frozen and then removed by sublimation under reduced pressure. The method preserves heat-sensitive materials that would degrade in conventional drying. Large-scale use grew during the mid-twentieth century for blood plasma and antibiotics, and it later expanded to vaccines, enzymes, foods, and advanced materials. The process produces a dry, porous solid that usually reconstitutes rapidly. It is distinct from simple evaporation because the solvent bypasses the liquid phase during primary removal.
| 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. |
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.
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.
The low pressure used during drying allows water vapor to move from the ice surface to a cold condenser. Energy supplied as heat drives sublimation but must stay below the collapse temperature of the frozen matrix. If the product becomes too warm, the frozen structure may soften or melt, reducing pore formation and slowing drying. Formulations often include bulking agents, stabilizers, or buffers to support a rigid cake. The final moisture content depends on formulation, freezing rate, and the length of secondary drying.
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.
After drying, a lyophilized product is usually sealed under vacuum or an inert gas to limit moisture uptake. Residual water content is measured because small changes can alter chemical stability and cake appearance. Storage temperature depends on the material; many biological products are kept at 2–8 °C, while some require −20 °C or colder. Exposure to ambient humidity during handling can cause the porous solid to absorb water and collapse. Container closures and stoppers are therefore selected for low moisture transmission and compatibility.
Quality control for lyophilized materials includes visual inspection of the cake, measurement of residual moisture, and tests for reconstitution time. An acceptable cake is typically uniform and may be slightly porous; shrinkage, meltback, or cracks can indicate process deviations. Analytical methods such as Karl Fischer titration, thermogravimetric analysis, and near-infrared spectroscopy quantify water content. Reconstitution time is recorded because a very slow or incomplete dissolution can signal collapse or aggregation. Stability studies compare samples stored under defined temperature and humidity conditions over months or years.
=== Toxicity === There are two aspects to the harmful effects of plutonium: radioactivity and heavy metal poisoning. Plutonium compounds are radioactive and accumulate in bone marrow. Contamination by plutonium oxide has resulted from nuclear disasters and radioactive incidents, including military nuclear accidents where nuclear weapons have burned. Studies of the effects of these smaller releases, as well as of the widespread radiation poisoning sickness and death following the atomic bombings of Hiroshima and Nagasaki, have provided considerable information regarding the dangers, symptoms and prognosis of radiation poisoning, which in the case of the Japanese survivors was largely unrelated to direct plutonium exposure. The decay of plutonium, releases three types of ionizing radiation: alpha (α), beta (β), and gamma (γ). Either acute or longer-term exposure carries a danger of serious health outcomes including radiation sickness, genetic damage, cancer, and death. The danger increases with the amount of exposure. α-radiation can travel only a short distance and cannot travel through the outer, dead layer of human skin. β-radiation can penetrate human skin, but cannot go all the way through the body. γ-radiation can go all the way through the body. Even though α radiation cannot penetrate the skin, ingested or inhaled plutonium does irradiate internal organs. α-particles generated by inhaled plutonium have been found to cause lung cancer in a cohort of European nuclear workers.
A nasal septum perforation is a medical condition in which the nasal septum, the bony/cartilaginous wall dividing the nasal cavities, develops a hole or fissure. Nasal administration may cause nasal septum perforation by gradually injuring and ulcerating the epithelium, causing cartilage exposure and necrosis.
In a joint statement on 13 January 2026, the prime ministers of Greenland and Denmark said that Greenland was facing an "unacceptable pressure" campaign and a "geopolitical crisis" caused by the US. They said that Greenland is not for sale under any circumstances. Frederiksen said, "our message is clear: Greenland is not for sale" and "you can't buy another people". Nielsen emphasised that talk about buying another people shows a lack of respect, and that Greenland does not want to be owned nor governed by the US. Greenlandic politicians have welcomed a NATO mission in Greenland to protect the island following Trump's threats.
The raised square bar and multilevel dining became the company standard. Dallas doubled the sales and tripled profits of TGI Fridays' previous best. Families began visiting the new suburban locations during the day for casual food; "it took six or seven years, but T.G.I. Fridays became a very different animal", Stillman said. Attracted by this performance, he merged into the Dallas franchise, forming TGI Fridays, Inc., and Scoggin was the CEO for the next 15 years. Scoggin is credited with the then-new 200-seat prototype and many of the TGI Fridays innovations including a large from-scratch menu, potato skins, bartender Olympics, and frozen drinks. In 1975, the company was sold to Carlson Companies, and Stillman and the original investors departed. Stillman kept the original location and, now married, founded Smith & Wollensky in 1977 with Benson. Scoggin continued as CEO on an earn-out contract and finalized his sale in 1980, signing a new contract to continue as the company's CEO. When the company was passing through the 100-store mark, it issued an initial public offering in 1983 with Goldman Sachs. Scoggin developed the first international franchise and the template for future international development. The first restaurant was opened in the UK with Whitbread PLC. By the time Scoggin departed in 1986, the company had widened its appeal: alcohol consumption was de-emphasized, and quality was emphasized over quantity. The company became privately held again in 1989. The focus was then switched from singles to families.
Sources: en.wikipedia.org
The Society recognizes achievements and promotes academic research through four annual awards. The Biemann Medal and the John B. Fenn Award for a Distinguished Contribution in Mass Spectrometry both are awarded in recognition of singular achievements or contributions in fundamental or applied mass spectrometry, with the Biemann Medal being focused on individuals who are early in their careers. The Ronald A. Hites Award is awarded for outstanding original research demonstrated in papers published in the Journal of the American Society for Mass Spectrometry. The Research Awards are given to young scientists in mass spectrometry, based on the evaluation of their proposed research. The Fellows of ASMS are awarded to individuals in recognition for their scientific contribution to mass spectrometry and for their contribution to the ASMS community. Journal of the American Society for Mass Spectrometry Measuring Mass: From Positive Rays to Proteins The past presidents of ASMS are:
The structure of CARD11 involves multiple domains that impact the protein's ability to activate BCL10 and NF-κB activity. CARD11 has a CARD domain, a serine-threonine rich region, is associated with the N-terminus, which is essential for NF-κB signaling activity. The region following the CARD domain is highly coiled. In deleting the CARD domain, all NF-κB signaling activity was prevented. The CARD domain on CARD11 interacts with the CARD domain on BCL10 to initiate the signaling pathway. On the C-terminus of CARD11 there is the MAGUK domain that is associated with the cell membrane. This domain is often referred to as the inhibitory domain. Protein kinase C activates CARD11 by phosphorylating serine residues within the inhibitory domain. CARD11 has been shown to interact with BCL10. This interaction occurs between the CARD domain on BCL10 and the CARD domain on CARD11, and results in signal propagation and NF-κB activation. Human CARD11 genome location and CARD11 gene details page in the UCSC Genome Browser.
Recent studies have discovered a pathway that links stress to the onset of disease through the activation of certain genes. The experience of psychological stress activates transcription factors that activate genes. In a study by Cole et al., it was concluded that GABA-1 transcription factor activates the interleukin-6-gene. This gene codes for a protein that activates the inflammatory response which directs an immune response to the site of the inflammation. Chronic inflammation makes an individual more susceptible to diseases such as cancer, heart disease, and diabetes. Another study found that physical stress caused increased cortisol:DHEAS (dehydroepiandrosterone sulphate) molar ratios which may contribute to reduced immunity, especially in the elderly for whom cortisol:DHEAS ratios are already increased. This is because DHEAS levels decrease with age while cortisol levels do not. This high ratio was found to suppress the activity of neutrophils and raise susceptibility for infection.
Sources: en.wikipedia.org
== Adverse effects == Ziprasidone (and all other second generation antipsychotics (SGAs)) received a boxed warning in the US due to increased mortality in elderly people with dementia-related psychosis. Sleepiness and headache are very common adverse effects (>10%). Common adverse effects (1–10%), include producing too much saliva or having dry mouth, runny nose, respiratory disorders or coughing, nausea and vomiting, stomach aches, constipation or diarrhea, loss of appetite, weight gain (but the smallest risk for weight gain compared to other antipsychotics), rashes, fast heart beats, blood pressure falling when standing up quickly, muscle pain, weakness, twitches, dizziness, and anxiety. Extrapyramidal symptoms are also common and include tremor, dystonia (sustained or repetitive muscle contractions), akathisia (the feeling of a need to be in motion), parkinsonism, and muscle rigidity; in a 2013 meta-analysis of 15 antipsychotic drugs, ziprasidone ranked 8th for such side effects. Ziprasidone is known to trigger mania in some bipolar patients. This medication can cause birth defects, according to animal studies, although this side effect has not been confirmed in humans. Recently, the FDA required the manufacturers of some atypical antipsychotics to include a warning about the risk of hyperglycemia and Type II diabetes with atypical antipsychotics. Some evidence suggests that ziprasidone does not cause insulin resistance to the degree of other atypical antipsychotics, such as olanzapine.
Liu Wenhui travelled to Chongqing to negotiate with Liu Xiang, but Liu Xiang would not hand over the confiscated shipment. This was because Liu Xiang had a policy of not allowing any other Sichuanese warlord to gain aircraft (he himself had already acquired a rudimentary air force consisting of several Potez 25 and Breguet 14 bombers). Western sources also agree that Liu Wenhui tried obtaining aircraft, although according to them the aircraft were either seized in Hankou by the central government or crashed en route to Chengdu. The Chinese sources go further by asserting that in May 1931, Liu Wenhui attempted to bribe Liu Xiang's subordinates, including Fan Shaozhen, to join him, but they reported this matter to Liu Xiang, causing Liu to waste 450,000 yuan. An angered Liu supposedly then cut off Liu Xiang's grain supply, forcing the Chongqing warlord to urgently purchase grain from Hunan to prevent hunger. Whatever the matter, it is clear that Liu Wenhui's once-cooperative relationship with his nephew, General Liu Xiang, had soured and turned into a rivalry. On 19 October 1932, Liu Xiang's general, Tang Shizun, and ninety-four other Sichuanese warlords issued a circular telegram to denounce Liu Wenhui. The telegram asserted that Liu was power-hungry, unscrupulous, corrupt, and nepotistic, with no real plans for governing Sichuan and resorting to underhanded tactics such as bribery, backstabbing, and banditry to gain and maintain power. On the eve of war in 1932, Liu Wenhui's armies were estimated at around 120,000 men, slightly outnumbering Liu Xiang's 100,000.
There is a wide variety in the mechanical properties achievable in biosynthetic spider silk depending on the spidroin sequences used, spinning method, native spider species and whether efficiency in production or maximum mechanical properties are emphasized.
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.
Yes. Lyophilization and freeze-drying are synonyms for the same vacuum-assisted sublimation process. The term lyophilization is more common in pharmaceutical and laboratory settings, while freeze-drying is widely used in food and general contexts.