Cryo Protective Agent
Cryo Protective Agent - Related Videos
01:24
Drugs for Peptic Ulcer Disease: Sucralfate as Mucosal Protective Agents
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2024
In the intricate landscape of the gastric lumen, excessive acid secretion disrupts the natural defense mechanisms, weakening the mucus-bicarbonate barrier. This vulnerability allows pepsin to infiltrate epithelial cells, digesting mucosal proteins and triggering erosion, leading to ulcer formation. In this scenario, mucosal protective agents like sucralfate play an essential role. Sucralfate, a complex of sulfated sucrose and aluminum hydroxide, demonstrates its usefulness in acidic conditions,...
11:27
Preparation and In Vitro Characterization of Dendrimer-based Contrast Agents for Magnetic Resonance Imaging
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Cited by 5 •
2016
This protocol describes the preparation and characterization of a dendrimeric magnetic resonance imaging (MRI) contrast agent that carries cyclen-based macrocyclic chelates coordinating paramagnetic gadolinium ions. In a series of MRI experiments in vitro, this agent produced an amplified MRI signal when compared to the commercially available monomeric analogue.
01:20
Drugs for Peptic Ulcer Disease: Prostaglandin Analogs as Mucosal Protective Agents
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2024
The gastric mucosa produces prostaglandins E2 (PGE2) and prostacyclin (PGI2), crucial in maintaining gastric health. They exert cytoprotective effects, including increasing bicarbonate secretion, releasing protective mucin, reducing gastric acid output, and preventing harmful vasoconstriction. These effects are mediated through various receptors, such as EP1, EP2, EP3, and EP4. Non-steroidal anti-inflammatory drugs (NSAIDs) can induce peptic ulcers by inhibiting cyclooxygenase, decreasing...
10:19
Reducing Agents
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2023
Source: Vy M. Dong and Daniel Kim, Department of Chemistry, University of California, Irvine, CA Controlling the reactivity and selectivity during the synthesis of a molecule is very important criteria for chemists. This has led to the development of many reagents that allow chemists to pick and choose reagents suitable for a given task. Quite often, a balance between reactivity and selectivity needs to be achieved. This experiment will use IR spectroscopy to monitor the reaction and to...
10:54
Cryo-electron Microscopy Specimen Preparation By Means Of a Focused Ion Beam
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Cited by 5 •
2014
Cryo Electron Microscopes, either Scanning (SEM) or Transmission (TEM), are widely used for characterization of biological samples or other materials with a high water content1. A SEM/Focused Ion Beam (FIB) is used to identify features of interest in samples and extract a thin, electron-transparent lamella for transfer to a cryo-TEM.
FAQs
The key distinction is where the agent acts relative to the cell. Intracellular agents can enter cells and influence water movement within them, whereas extracellular agents remain outside and help shape the surrounding freezing environment. This difference affects how osmotic stress is managed and guides selection for particular cells, tissues, embryos, gametes, or microorganisms.
Ice formation can damage biological structures, while temperature changes drive water movement across cellular boundaries. A cryoprotective agent helps limit these stresses by reducing ice-crystal formation and moderating shifts in water distribution. Effective protection therefore depends on preserving cellular conditions during both cooling and warming, rather than addressing freezing alone.
Concentration determines whether protection outweighs toxicity. Too little agent may leave cells vulnerable to ice-related injury, uncontrolled water movement, or osmotic stress. Too much can expose cells to chemical or osmotic toxicity. Cryopreservation protocols therefore require a balance between sufficient protection and acceptable exposure for the specific biological material.
A general workflow includes selecting an agent suited to the biological material, applying it at an appropriate concentration, freezing the material, and later removing or reducing the agent during thawing-related handling. Each stage matters because protection must continue through temperature change without creating excessive chemical or osmotic stress.
Cryoprotective agents support preservation of a broad range of biological materials, including cells, embryos, gametes, tissues, and microorganisms. Their use allows these materials to remain available for later study or application after freezing and thawing. The appropriate chemistry and concentration depend on the material’s sensitivity to cellular, osmotic, and chemical injury.
In biology, these agents contribute to cryopreservation programs in research, reproductive medicine, biobanking, and regenerative applications. Preserved cells, embryos, gametes, tissues, and microorganisms can support investigations or future use without requiring continuous activity at normal temperatures. Outcomes depend on maintaining viability and limiting damage throughout the freezing and thawing process.