amino acid analysis Hydrolysis of a protein or peptide into its individual residues (free amino acids), followed by chromatographic separation
and UV-visible detection for analytical purposes.
amino acids A class of 20 naturally occurring hydrocarbon molecules that combine to form proteins in living things. They include alanine
(A), arginine (R), asparagine (N), aspartic acid (D), cysteine (C), glutamic acid (E), glutamine (Q), glycine (G), histidine
(H), isoleucine (I), leucine (L), lysine (K), methionine (M), phenylalanine (F), proline (P), serine (S), threonine (T), tryptophan
(W), tyrosine (Y), and valine (V). (Those are the so-called normal amino acids; others have been synthesized and are used
in medicinal chemistry.) They are incorporated into proteins by transfer RNA according to the genetic code.
amorphous Having no apparent shape or order; non-crystalline.
ampholyte An electrolyte that can be either positively or negatively charged, depending on the pH of its medium.
amphoteric A substance that has both acid and base properties; amphoteric molecules can accept or donate protons to act as an acid or
ampule A small, sterile glass vessel with an airtight seal that contains a single drug dose.
amyloid Insoluble fibrous protein aggregates sharing specific structural traits. Abnormal accumulation of amyloid in organs may lead
to amyloidosis and may play a role in various other neurodegenerative diseases.
anaerobic Growing in the absence of air or oxygen. Some anaerobic organisms are killed by brief exposure to oxygen, whereas it may simply
retard or stop the growth of others.
analytical methods Processes used to analyze or characterize a mixture, a compound, or an unknown material.
anion A negatively charged ion (having more electrons than protons).
annual review An evaluation, conducted at least annually, which assesses the quality standards of each drug product to determine the need
for changes in drug
product specifications or manufacturing or control procedures. [From FDAQSG]
anodes Positive electrodes; negative ions (anions) migrate carrying electric current toward positive anodes.
antibody An infection-fighting protein molecule that tags, neutralizes, and helps destroy foreign microorganisms or toxins. Also known
as immunoglobulins, antibodies are produced by the immune system in response to antigens.
antifoam agent A chemical added to a fermentation broth to counteract the foaming (bubbles) that can be caused by mixing, sparging, or stirring.
antigen Any agent that reacts specifically with an antibody. Each antigen may contain more than one site capable of binding to a particular
antibody. (See immunogen)
antigenicity The capacity of a substance to induce the formation of antibodies or to elicit an immune response when injected into an animal.
Amino acid analysis can be used to quantitatively determine the amount of protein and the proportions of amino acids in a
sample. The Waters UPLC Amino Acid Analysis Solution is a turnkey chromatographic system that provides accurate, high-throughput
amino acid analysis.
antisense oligonucleotides Antisense oligonucleotides interact with complementary strands of nucleic acids, modifying expression of genes.
Active pharmaceutical ingredient; the chemical entity that has the drug activity and structure, but is not yet formulated with excipients.
aprotinin A polypeptide that inhibits (blocks the action of) serine proteases.
aptamer Single-stranded RNA or double-stranded DNA molecules made up of short lengths of nucleic acids that form three-dimensional
structures and can bind to specific endogenous targets to produce its biological action.
aqueous solution A solvent solution made with water.
Arginine; one of more than 20 naturally occurring amino acids.
artificial chromosome DNA synthesized in chromosomal form for use as an expression vector.
aseptic Sterile, free from bacteria, viruses, and other pathogenic contaminants.