Top Tweets for #pharmaceutical_methods
#Positive_pressure_rooms maintain a higher pressure inside the treated area than that of the surrounding environment. This means air can leave the room without circulating back in.
#Pharmaceutical_Methods
#Electrochemical_detection (ECD) coupled with HPLC is a powerful tool for the detection of neurotransmitters, environmental assessment, and the detection of phenol compounds from food samples. Various neurotransmitters are detectable.
#Pharmaceutical_Methods
#Chronoamperometry is the technique in which the current is measured, at a fixed potential, at different times since the start of polarisation.
#Pharmaceutical_Methods
The M+2 #peak in a mass spectrum arises from the presence of chlorine or bromine atoms in an organic compound. It also deals briefly with the origin of the M+4 peak in compounds containing two chlorine atoms.
#Pharmaceutical_Methods
#Fluorescence_quenching refers to any process that decreases the fluorescence intensity of a sample due to excited-state reactions, molecular rearrangements, energy transfer, ground-state complex formation, and colli-sional quenching.
#Pharmaceutical_Methods
Bragg's method is a technique in which a beam of x-rays is directed against a #crystal, the atoms of which, because of their lattice arrangement, reflect the ray in the same way as a series of plane surfaces.
#Pharmaceutical_Methods
#Method_validation data provide information which enables the comparability of results from samples analysed in different laboratories and using different methods to be assessed ensuring that measurement results reported to customers are correct.
#Pharmaceutical_Methods
Vacuum distillation is ideal for separating mixtures of liquids with very high #boiling_points. In order to boil these compounds, heating to high temperatures is an inefficient method.
#Pharmaceutical_Methods
#Vacuum_distillation is the process of lowering the pressure in the column above the solvent to less than the vapor pressure of the mixture, creating a vacuum, and causing the elements with lower vapor pressures to evaporate off.
#Pharmaceutical_Methods
The #combination_column is used to separate the argon and oxygen peaks; the oxygen is eliminated due to the catalytic reaction with hydrogen (hydrogen is used as the carrier gas), so only the argon peak is eluted.
#Pharmaceutical_Methods
An #ideal_gas is one that follows the gas laws at all conditions of temperature and pressure. To do so, the gas needs to completely abide by the kinetic-molecular theory.
#Pharmaceutical_Methods
Difference between #UHPLC and HPLC is the size of used particles filled into the column. Particle sizes ≤ 2 µm are commonly used for UHPLC. Particles with a size of 3 µm up to 5 µm are usual for classical analytical HPLC.
#Pharmaceutical_Methods
A common packing material for #size_exclusion_chromatography_columns is molecular sieves. Zeolites are a common molecular sieve that is used. The molecular sieves have pores that small molecules can go into, but large molecules cannot.
#Pharmaceutical_Methods
Usually HPLC has a #guard_column ahead of the analytical column to protect and extend the life of the analytical column. The guard column removes particulate matter, contaminants, and molecules that bind irreversibly to the column.
#Pharmaceutical_Methods
#Emulsions can be disrupted by the addition of brine or salt water, which increases the ionic strength of the aqueous layer and facilitates separation of the two phases by forcing the surfactant-like molecule to separate into one phase or the other.
#Pharmaceutical_Methods
Another well-established HighG-technology is the #rotating_extractive_centrifuge, which is often used for liquid-liquid extractions and is operated with g-forces between 200 and 2000.
#Pharmaceutical_Methods
The initial role of the #ethanol and monovalent cations is to remove the solvation shell surrounding the DNA and permitting the precipitation of the DNA in pellet form. The ethanol also serves to promote the aggregation of the DNA.
#Pharmaceutical_Methods
#Solid_phase_DNA_extraction exploits interactions of DNA with a solid substrate, such as silica resin/beads in the presence of chaotropic salts, allowing for rapid purification of DNA from digested samples.
#Pharmaceutical_Methods
The absorption of #IR_radiation causes bonds to stretch and bend. Stretches correspond to the increasing and decreasing of the bond lengths within a molecule. Bends correspond to the increasing and decreasing of the angle between bonds in a molecule.
#Pharmaceutical_Methods
#Vibrational_dephasing is caused by several factors including intramolecular vibrational energy redistribution (IVR), pure dephasing, ensemble effect, etc. This result strongly indicates that the dephasing of these vibrational modes is influenced by ET. #Pharmaceutical_Methods
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