Bioavailability
Also known as: oral bioavailability · systemic availability
The fraction of an administered dose that actually reaches circulation intact — low for oral peptides, higher for injection.
Bioavailability is the proportion of an administered amount that reaches the bloodstream in active form. The route matters enormously: injection is close to complete, while other routes lose material along the way.
It is the central challenge for oral peptides: the digestive tract breaks peptide bonds, so oral bioavailability is usually very low. This is why most research peptides are studied via injected or intranasal routes, and why stability modifications matter.
RELATED TERMS
Subcutaneous
Into the layer of fat just beneath the skin — the route most peptide research protocols reference.
Intramuscular
Into muscle tissue — a delivery route with faster absorption than subcutaneous, referenced in some research protocols.
Intranasal
Delivery through the nasal lining — the route some peptides such as Semax and Selank are studied via.
Half-Life
The time for a compound’s concentration to fall by half — a key determinant of dosing frequency in research.
Stability
How well a peptide resists degradation over time under given conditions — the property that dictates storage and handling.
Educational content, not medical advice. All products supplied for research purposes only — not for human consumption.