undercooling An uncommon method of biomolecular preservation in which emulsions are used to cool the solution below its freezing point
underflow The dewatered solids that result from compaction during centrifugation.
unfolding A form of protein degradation in which the three-dimensional structure of a molecule unravels to something that more closely
resembles a basic chain of amino acids.
unicellular A single-cell organism.
unit operation A distinct chemical or physical step in a downstream process, such as ultrafiltration, centrifugation, or chromatography.
USP or USP-NF The United States Pharmacopeial Convention, Inc., which establishes and disseminates officially recognized standards of quality and authoritative information for the use in
the manufacture and testing of drugs, excipients, and raw materials. Also called one of the compendia. Other compendia include,
for example, Ph.Eur (Pharmacopeia Europa), JP (Japanese Pharmacopeia). The USP, which defined specifications for approved drugs as well as general methods and guidances, merged with the NF, National Formulary, which focused on specifications for raw materials and excipients. General chapters are not legally binding,
but specific chapters are considered to be binding, and defined USP methods are accepted by the FDA as an appropriate standard.
USP sterility test A method defined in the USP and Ph.Eur, and considered acceptable for per-lot testing of parenteral drugs to test for sterility. By itself, this test does not prove
a given lot is sterile; rather, taken together with all other validation, GMP controls, and product/process testing, it increases
confidence that a given lot is safe. (See sterility).
Ultraviolet-visible spectroscopy, an analytical method that measures the absorption of light in the 200–750 nm range of the electromagnetic spectrum.
It is used in determining protein concentration and is often applied to HPLC detection.
vaccines Preparations that elicit an immune response (production of antibodies) to protect a person or animal from a disease-causing
vacuolation In cell and tissue culture, excess fluid, debris (aggregates), or gas (from sparging) can form inside a cell vacuole, a
cavity within the cell that can be relatively clear and fluid filled, gas filled (as in a number of blue-green algae), or
food filled (as in protozoa).
Valine, one of over 20 naturally occurring amino acids.
validation 1. Documented evidence that shows that an assay or process, when operated within specified ranges of critical parameters, has
a high probability of specifications. 2. The process of determining the degree of validity; the procedures involved in checking
data for correctness, compliance with standards, and conformance with the requirement specifications. A series of experiments
performed using a pre-approved protocol, that will generate adequate documented evidence to support a claim of a validated
Variant Creutzfeld-Jakob disease; a fatal neurological disease in humans, believed to be caused by infection with a prion that also causes bovine spongiform
encephalopathy (BSE) or "mad cow disease" in cattle. CJD, or classical CJD, is not caused by the BSE agent, and its etiology
vector The plasmid, virus, or other vehicle used to carry an r-DNA sequence into the cell of another species.
venture capital Also risk capital; money invested in a small, young, or start-up company that is perceived to have excellent growth prospects but without other
access to capital markets. Venture capitalists generally supply capital in return for substantial equity and/or a seat on
the board of directors. Sometimes, they provide management and other financial support to their investee companies.
Vero An established cell line derived from the kidney of the African green monkey.