Biotech terms, in plain words.

A

Affinity capture

A way of isolating particles using a binder, such as an antibody, that attaches to a chosen surface marker.

Antibody

A protein that binds a specific target, used in research and diagnostics to identify or capture molecules.

B

Bioavailability

The share of a substance that reaches the place in the body where it is meant to act.

Biosafety cabinet

A ventilated enclosure that protects both the work and the worker when handling cells and samples.

C

Cargo

The proteins, lipids or nucleic acids carried inside a vesicle or a delivery particle.

Cell banking

Freezing a well-characterised set of cells in many identical vials so that later work starts from the same material.

Certificate of analysis

A document listing the tests run on a batch and the results, signed by the quality function.

Cleanroom grade

A rating of how clean a controlled room is, with Grade A the cleanest and Grade D the least strict of the classified grades.

Conditioned medium

The liquid in which cells have been grown, containing the factors and vesicles they have released.

Cytokine

A small signalling protein released by cells that influences how other cells behave.

D

Deviation

Any departure from an approved procedure, recorded and investigated in a quality system.

Dynamic light scattering

A method that estimates particle size by measuring how light scattered from particles fluctuates over time.

E

Encapsulation efficiency

The share of a payload that ends up enclosed inside a carrier, such as a liposome, instead of staying free.

Endotoxin

A fragment of the outer wall of some bacteria that can cause strong reactions, so it is tested for in many materials.

Exosome

A small membrane-bound vesicle, usually tens to a couple of hundred nanometres across, released by cells and carrying proteins, lipids and nucleic acids.

Extracellular vesicle

The broad family of membrane-bound particles that cells release, which includes exosomes.

F

Flow cytometry

A method that reads markers on thousands of single cells per second as they pass a laser.

G

GMP

Good Manufacturing Practice, the set of quality rules for making products intended for human use.

Growth factor

A protein that tells cells to grow, divide or change, often found in what stem cells secrete.

I

Immunoassay

A test that uses antibodies to detect or measure a specific substance in a sample.

L

Limit of detection

The lowest amount of a target that an assay can reliably tell apart from nothing.

Lipid bilayer

Two layers of lipid molecules arranged tail to tail, forming the membrane of cells, vesicles and liposomes.

Lipid nanoparticle

A lipid-based carrier with an internal structure suited to nucleic acids, widely used to deliver RNA.

Liposome

A hollow sphere made of a lipid bilayer, with a watery core that can hold a payload.

M

Marker protein

A protein on or in a particle or cell that helps identify what it is.

Mesenchymal stem cell

A multipotent cell found in tissues such as bone marrow and fat, studied for the factors it secretes and its ability to modulate its surroundings.

Multiplex assay

A test that looks for several targets at once in a single sample.

N

Nanoparticle tracking analysis

A method that follows individual particles under a microscope to estimate their size and concentration.

O

Organoid

A small three-dimensional culture that mimics aspects of the structure and behaviour of a real tissue.

P

Passage

One round of growing cells until they fill their dish, then dividing them into new dishes.

Phenotype

The observable characteristics of a cell, such as the markers on its surface.

Point of care

Testing carried out close to the patient, rather than in a central laboratory.

Polydispersity index

A number describing how uniform the sizes are in a population of particles, with lower values meaning more uniform.

Potency assay

A functional test showing that a product does the biological activity it is meant to do.

S

Secretome

The full set of molecules and vesicles that a cell releases into its surroundings.

Size-exclusion chromatography

A column method that separates particles by size, with larger ones passing through faster than smaller ones.

Specificity

How well an assay avoids reacting to anything other than its intended target.

Stability study

A planned test showing how a material holds up over time under stated storage conditions.

T

Tangential flow filtration

A filtration method in which fluid flows across a membrane, letting small molecules through while retaining larger particles.

Transmission electron microscopy

A microscope that images extremely small structures, including vesicles, using a beam of electrons.

U

Ultracentrifugation

Spinning samples at very high speed so that particles separate by size and density.

Z

Zeta potential

A measure of the electrical charge at a particle's surface, which affects how stable a suspension is.