silica Silicon dioxide,SiO2, occurring naturally in crystalline, microcrystalline, and amorphous form; used to make glass and ceramics, and used in pharmaceuticals.
Silica gel is a jelly-like form of silicon dioxide that is widely used as a solid medium, as a dehumidifying and dehydrating
agent, and in many chemical processes.
Steam-in-place; using steam to clean and sterilize equipment or systems without removing them from their installed location. (See CIP)
Small interfering RNA, short interfering RNA, or silencing RNA a class of 20 to 25 nucleotide-long double-stranded RNA molecules that play a variety of roles in biology. Most notably, siRNA
is involved in the RNA interference (RNAi) pathway, where it interferes with the expression a specific gene. (See RNAi)
skid Common term for a complete chromatography system on wheels.
Simulated moving bed; a method in liquid chromatography of making separations constant rather than in a batch process.
sodium hydroxide A highly caustic, alkaline chemical (NaOH) used to neutralize acids and destroy soft body tissues (with potassium hydroxide,
the most widely used caustic agent in industry).
solubility The degree to which a solute can be dissolved in a defined solvent (sometimes describes the opposite of hydrophobicity).
solute A substance that is dissolved in a solvent; the part of a solution that is uniformly dispersed in another substance.
somatic cell In higher organisms, a cell that (unlike germ cells) carries the full genetic make-up of an organism.
Standard operating procedures; detailed (step-by-step), instructions to achieve uniformity in the performance of a specific process or piece of equipment,
which are approved by the quality control unit and used for GMP operations.
Southwestern blot Analytical blotting technique for studying DNA-protein interactions using labeled DNA to detect proteins transferred to membrane
sparge To spray. A sparger is the component of a fermentor that sprays air into the broth.
species In chemistry, a particular kind of atomic nucleus, atom, molecule, or ion.
specifications Tests, analytical procedures, and appropriate acceptance criteria that are numerical limits or ranges that establish a set
of criteria to which a raw material, drug substance, or drug product must conform to be considered acceptable for its intended
specificity The degree to which a substance exerts a definitive and distinctive influence on a particular part of the body and on the
course of a particular disease.
spectrometry Spectroscopy methods related to measurements of mass.
spectroscopy Study of the molecular absorption of light using optics. Different wavelengths and types of light can tell different things
about the molecules' identity and condition. Proteins are often studied using fluorescence and infrared (see FT-IR) spectroscopy.
Fluorescence spectroscopy induces molecules to emit light by the application of laser energy.
spike Adding a known amount of analyte from a laboratory standard, sometimes with something highly reactive (such as a radioactive
or fluorescent dye) to act as a tracer. Used to check a method for recovery or accuracy.
sponsor Organization that takes primary ownership and responsibility for a product, and usually will be the license holder. A sponsor
may outsource testing, clinical trials, or manufacturing to other entities (CLO, CRO, CMO) but retains oversight of the program.
The exact division of roles is specified in contracts and in the quality agreement, a key GMP document.
spray-drying Creation of a fine powder by passing a bulk or final drug formulation through a hot air stream to evaporate dispersed droplets;
contrast with freeze-drying.