Glossary

Dit artikel beschrijft onderzoek en analysemethoden. Het is geen dosering-, gebruiks- of medisch advies. Onze producten zijn alleen voor laboratoriumonderzoek.

The terms you encounter on product pages, labels, and analysis reports, briefly explained.

Aliquot

A measured portion of a solution, intended for a single analysis or experiment. Working with aliquots prevents opening the entire vial repeatedly.

Bacteriostatic water

Sterile water with 0.9 % benzyl alcohol as a preservative. This allows multiple withdrawals from the same vial. The standard solvent for lyophilised powder.

Batch and lot

A batch is a single production run. The lot number on the label links your vial to that batch and to the corresponding analysis report.

CAS number

A unique registration number assigned by the Chemical Abstracts Service. Two substances with different names but the same CAS number are the same compound.

Concentration

The amount of substance per volume of solution, usually in mg/ml or IU/ml. Vial content divided by the volume of solvent in ml. The calculator calculates this for you.

Endotoxin

Remnants of the cell wall of certain bacteria. The content is measured using a LAL test and expressed in EU per mg. Not every report includes this measurement.

FTIR

Fourier-transform infrared spectroscopy. Provides a spectral fingerprint of a substance and is used to confirm identity.

Content (quantitative determination)

The measured amount of substance in the vial, for example 9.8 mg for a stated 10 mg. This is distinct from purity.

Lyophilised

Freeze-dried. Water has been removed from the frozen material under vacuum, leaving a dry powder or 'cake' that is more stable than a solution.

HPLC

High-performance liquid chromatography: liquid chromatography that separates the components in a sample. Purity is the proportion of the main peak relative to the total peak area.

IU

International Unit. A unit of measurement for biological activity, used for substances such as hCG and somatropin, instead of milligrams.

LC-MS and MS

Mass spectrometry measures the mass of molecules. If the measured mass corresponds to the expected mass, the identity is confirmed. In LC-MS, this is preceded by separation via liquid chromatography.

Molecular weight

The mass of a single molecule, expressed in g/mol or daltons (Da).

Peptide

A short chain of amino acids, ranging from two to approximately forty. Longer, folded chains are called proteins.

Reconstitution

Dissolving lyophilised powder in a solvent. See the reconstitution guide.

Research use only (RUO)

Intended exclusively for laboratory and in vitro research. Not for human or animal use and not for diagnosis, treatment, or prevention.

Septum

The rubber stopper in the neck of a vial. Clean it with an alcohol wipe and allow it to dry before piercing.

TFA

Trifluoroacetic acid. Often remains bound to the peptide as a counterion (TFA salt) after synthesis and purification. Some reports state the content.

U-100 scale

A scale graduation where 100 units equal 1 ml. One unit is therefore 0.01 ml.

Purity

The percentage of the measured material consisting of the target substance, usually determined by HPLC. Purity does not indicate the quantity in the vial; refer to the content determination for that.

All products from PEPTID8 are intended exclusively for laboratory and in vitro research. They are not intended for administration to humans or animals and are not medicinal products, dietary supplements, or cosmetic products. We do not provide advice regarding use or quantities.