Lyophilization
Lyophilization removes water by freezing and sublimation to create a dry solid. The resulting lyophilizate is still checked for residual water by Karl Fischer titration.
See also:
handling and storage
Research glossary
Peptide reference-standard glossary
Plain-language definitions of the analytical, structural, regulatory, and storage terms that appear on Canada Peptides Certificates of Analysis and across the research guide. 73 terms across five categories. Each entry links to related articles, product pages, and source references where useful.
Chemistry
Lyophilizate
A lyophilizate is the dry cake or powder produced by lyophilization. It should be read with storage condition, water content, and COA context.
See also:
handling and storage
Residue
A residue is an amino-acid unit after incorporation into a peptide chain. Residues connect through a peptide bond and carry side chain chemistry.
See also:
acetyl capped cosmetic peptides
Peptide bond
A peptide bond is the amide linkage joining amino-acid residues. It contributes to UV-Vis A205 absorbance and to metal coordination in some peptide complexes.
See also:
ghk cu copper peptide complexes
Products:
CP-035
Alpha-amino acid
An alpha-amino acid has the amino and carboxyl groups attached to the alpha carbon. Modified examples such as Aib, sarcosine, and D-amino acid variants change peptide behaviour.
See also:
ghrelin mimetic reference standards
Modified amino acid
A modified amino acid changes stereochemistry, side-chain bulk, terminal behaviour, or backbone properties relative to canonical residues. Examples include Aib, sarcosine, and D-amino acid.
See also:
ghrelin mimetic reference standards
Aib
Aib is alpha-aminoisobutyric acid, a sterically restricted modified residue used to tune peptide conformation and stability. It should be interpreted beside modified amino acid and N-terminal context.
See also:
ghrelin mimetic reference standards
Products:
CP-012
Sarcosine
Sarcosine is N-methylglycine, a methylated amino-acid derivative that changes backbone hydrogen-bonding behaviour. It belongs in the same glossary family as modified amino acid and peptide bond.
See also:
ghrelin mimetic reference standards
D-amino acid
A D-amino acid has the opposite stereochemical configuration from the common L-form. Mass spectrometry does not distinguish D and L forms by mass alone, so HPLC-MS must be interpreted with synthesis or chiral-method records.
See also:
ghrelin mimetic reference standards
N-terminal
The N-terminal end is the amino end of a peptide. It may be free, acetylated, lipidated, or otherwise modified, which changes molecular weight and HPLC retention.
See also:
acetyl capped cosmetic peptides
C-terminal
The C-terminal end is the carboxyl end of a peptide. It can be a free acid or amide and should be checked beside N-terminal state on modified peptide COAs.
See also:
cjc 1295 dac tesamorelin structure
Side chain
A side chain is the variable group attached to an amino-acid residue. Side-chain charge and hydrophobicity shape isoelectric point, retention, and amphipathic peptide behaviour.
See also:
ll37 magainin cationic peptides
Products:
CP-034
Isoelectric point pI
Isoelectric point is the pH at which a molecule has no net charge. It depends on side chain pKa values and terminal groups, especially in cationic peptides.
See also:
ll37 magainin cationic peptides
Products:
CP-034
Molecular weight
Molecular weight is the average mass value often shown on a catalog or COA. It should be distinguished from monoisotopic mass and from salt-adjusted mass.
See also:
reading a coa
Monoisotopic mass
Monoisotopic mass is calculated from the lightest stable isotopes of each element. It differs from average mass and is important for high-accuracy MS assignments.
See also:
alpha msh melanotan structural
Average mass
Average mass uses natural isotope abundance and is common in catalog molecular weight displays. It should be read beside monoisotopic mass and method tolerance.
See also:
reading a coa
Counter-ion
A counter-ion balances charge in a salt form and can change net mass per vial. Common examples include acetate salt, TFA salt, and hydrochloride salt.
See also:
ghk cu copper peptide complexes
Hydrochloride salt
A hydrochloride salt uses chloride as the counter-ion for a protonated molecule. It should be compared with acetate salt and TFA salt in mass accounting.
See also:
reading a coa
Acetate salt
An acetate salt contains acetate as the counter-ion. It changes gross material mass and should be disclosed beside counter-ion and molecular weight fields.
See also:
reading a coa
TFA salt
A TFA salt contains trifluoroacetate counter-ion remaining from peptide purification or salt exchange. It should be interpreted with trifluoroacetic acid and residual-solvent context.
See also:
reading a coa
Trifluoroacetic acid
Trifluoroacetic acid is commonly used in peptide HPLC mobile phases and can contribute to TFA salt forms. It links to TFA salt and HPLC interpretation.
See also:
reading a coa
Lipidation
Lipidation attaches a lipid group to a peptide, changing retention, solubility, and self-association. Palmitoylation is a common C16 lipidation example.
See also:
palmitoylated pentapeptide lipidation
Products:
CP-061
Palmitoylation
Palmitoylation attaches a C16 fatty acyl group to a molecule. In Matrixyl-style standards it should be read with lipidation, HPLC, and unmodified peptide impurity checks.
See also:
palmitoylated pentapeptide lipidation
Products:
CP-061
Glycation
Glycation is non-enzymatic attachment of reducing sugars to amino groups. It can affect side chain chemistry and should not be confused with glycosylation in protein contexts.
See also:
reading a coa
Oxidation
Oxidation adds oxygen or changes electron state in susceptible residues such as methionine. It should be tracked beside deamidation and HPLC-MS impurity profiles.
See also:
acetyl capped cosmetic peptides
Deamidation
Deamidation converts susceptible amide side chains to acid forms and can shift mass and charge. It is often reviewed beside oxidation and chromatographic peak shape.
See also:
epitalon tb500 nad reference standards
Products:
CP-031
Aggregation
Aggregation is self-association of molecules into larger assemblies. It can affect HPLC recovery, CD spectroscopy, and apparent purity.
See also:
ll37 magainin cationic peptides
Method
HPLC
High-performance liquid chromatography separates peptide species by retention on a column. It is often paired with LC-MS or HPLC-MS to connect purity with identity.
UPLC
Ultra-performance liquid chromatography uses smaller particles and higher pressure than conventional HPLC. It can sharpen peptide impurity resolution before HRMS confirmation.
See also:
reading a coa
LC-MS
Liquid chromatography coupled to mass spectrometry links chromatographic separation with mass-based identity. It is the broader method family that includes HPLC-MS workflows.
See also:
reading a coa
HPLC-MS
HPLC-MS couples HPLC separation with mass spectrometry identity confirmation. Canada Peptides uses the term to support research reference standard identity and purity review.
MALDI-TOF
Matrix-assisted laser desorption ionisation time-of-flight mass spectrometry measures peptide mass after matrix-assisted desorption. It complements ESI-MS for larger peptides and proteins.
See also:
ll37 magainin cationic peptides
ESI-MS
Electrospray ionisation mass spectrometry transfers peptide ions from solution into the gas phase. It is common in LC-MS and HPLC-MS identity workflows.
See also:
acetyl capped cosmetic peptides
HRMS
High-resolution mass spectrometry distinguishes close mass differences by resolving power and mass accuracy. It supports monoisotopic mass assignment for modified peptides.
See also:
alpha msh melanotan structural
Karl Fischer titration
Karl Fischer titration measures water content in a lyophilizate. The result affects mass accounting for reference standards and should be read beside COA purity lines.
See also:
reading a coa
GC headspace
GC headspace analysis measures volatile residual solvents released from a sealed sample vial. It is often connected to ICH Q3C(R8) residual-solvent limits.
See also:
reading a coa
LAL endotoxin test
The LAL endotoxin test detects bacterial endotoxin in materials where endotoxin control is relevant. It is separate from HPLC-MS identity and from SDS-PAGE size checks.
See also:
reading a coa
BCA assay
The bicinchoninic acid assay estimates protein or peptide concentration through copper-dependent colour formation. It should not be confused with amino acid analysis, which is a stronger absolute-content method.
See also:
acetyl capped cosmetic peptides
Amino acid analysis AAA
Amino acid analysis hydrolyses a peptide and quantifies released residues against standards. It can support content assignment when UV-Vis A205 or HPLC area percent is insufficient.
See also:
acetyl capped cosmetic peptides
CD spectroscopy
Circular dichroism spectroscopy estimates secondary-structure content under defined solvent conditions. It is useful for cationic peptides such as LL-37 when read beside NMR or HPLC-MS.
See also:
ll37 magainin cationic peptides
Products:
CP-034
NMR
Nuclear magnetic resonance spectroscopy can assign solution or micelle-bound peptide structure under stated conditions. It complements CD spectroscopy for conformational studies.
See also:
ll37 magainin cationic peptides
Products:
CP-034
Isoelectric focusing
Isoelectric focusing separates molecules by isoelectric point. It is more common for proteins than short peptides but helps explain charge-based separation logic.
See also:
ll37 magainin cationic peptides
Products:
CP-034
SDS-PAGE
SDS-PAGE separates proteins and larger peptides by apparent size after SDS binding. It is distinct from HPLC and is less informative for many short peptide reference standards.
See also:
reading a coa
UV-Vis A205
UV-Vis A205 uses peptide-bond absorbance near 205 nm. It is useful for Trp/Tyr-poor cosmetic peptides when controlled against buffer background and compared with amino acid analysis.
See also:
acetyl capped cosmetic peptides
Quality
RUO Research Use Only
RUO means Research Use Only and should be paired with the phrase not for human consumption or therapeutic use. It is a compliance frame separate from reference standard quality.
See also:
reading a coa
Reference standard
A reference standard is a characterised material used to support analytical comparison. It should be tied to a COA, lot number, and method record.
See also:
reading a coa
Primary reference material
A primary reference material has high metrological status and supports calibration of secondary materials. It sits above secondary reference material in traceability hierarchy.
See also:
reading a coa
Secondary reference material
A secondary reference material is calibrated against a primary reference material or validated method. It should be documented with lot number and COA evidence.
See also:
reading a coa
Certificate of Analysis COA
A Certificate of Analysis records identity, purity, lot, and supporting test results for a released material. It should connect HPLC-MS, Karl Fischer titration, and lot traceability.
See also:
reading a coa
Batch number
A batch number identifies a manufacturing or synthesis batch. It is related to, but not always identical with, the lot number on a COA.
See also:
reading a coa
Lot number
A lot number links a vial to the specific released material and COA. It should be checked beside batch number and retest date.
See also:
reading a coa
Expiry date
An expiry date is the supplier-stated date through which the sealed material is supported under stated storage. It should be read beside retest date and storage terms.
See also:
handling and storage
Retest date
A retest date indicates when a material should be rechecked if still held under inventory control. It differs from expiry date and depends on storage condition.
See also:
handling and storage
ICH Q3C(R8)
ICH Q3C(R8) is the residual-solvent guideline used to classify and limit solvents in materials. It links naturally to GC headspace and COA solvent lines.
See also:
reading a coa
USP
USP is the United States Pharmacopeia, a compendial standards body. It is distinct from EP and from supplier-specific research reference standard specifications.
See also:
reading a coa
EP European Pharmacopoeia
EP means European Pharmacopoeia. It is a compendial reference source and should be distinguished from USP and ISO 17025.
See also:
reading a coa
ISO 17025
ISO 17025 is an international standard for testing and calibration laboratory competence. It supports confidence in method execution but does not replace COA review.
See also:
reading a coa
Receptor
GLP-1R
GLP-1R is the glucagon-like peptide-1 receptor. It belongs with GIPR and GCGR in metabolic peptide receptor panels.
See also:
reading a coa
GIPR
GIPR is the glucose-dependent insulinotropic polypeptide receptor. It is commonly discussed beside GLP-1R and GCGR.
See also:
reading a coa
GCGR
GCGR is the glucagon receptor. It is a metabolic receptor comparator beside GLP-1R and GIPR.
See also:
reading a coa
Products:
CP-003
GHSR-1a
GHSR-1a is the ghrelin receptor used in many in-vitro binding and signalling assays. It anchors the ghrelin mimetic article and connects to modified peptide terms.
See also:
ghrelin mimetic reference standards
MC4R
MC4R is melanocortin receptor 4, a GPCR in the melanocortin family. It should be read beside MC1R and melanocortin receptor family.
See also:
alpha msh melanotan structural
MC1R
MC1R is melanocortin receptor 1, a receptor-family anchor for alpha-MSH analogue classification. It pairs with MC4R and melanocortin receptor family.
See also:
alpha msh melanotan structural
Products:
CP-051
Mu-opioid receptor
The mu-opioid receptor is a GPCR target outside the current Canada Peptides orphan set. It is included for receptor glossary coverage and should be kept separate from melanocortin receptor family entries.
See also:
reading a coa
Melanocortin receptor family
The melanocortin receptor family includes MC1R through MC5R and provides context for alpha-MSH analogues. This entry cross-links MC1R and MC4R.
See also:
alpha msh melanotan structural
Storage
-80 C storage
-80 C storage is ultra-low temperature storage used when a molecule-specific stability file calls for it. It should be compared with -20 C storage and 4 C storage.
See also:
handling and storage
-20 C storage
-20 C storage is a common sealed-vial condition for lyophilized peptide reference standards. It should be read with lyophilized stability and cold-chain shipping.
See also:
handling and storage
4 C storage
4 C storage is refrigerated storage used for short-term holding only when supported by the lot file. It should not be assumed from -20 C storage instructions.
See also:
handling and storage
Lyophilized stability
Lyophilized stability describes the supported stability of the sealed dry material. It depends on lyophilizate quality, water content, seal integrity, and storage temperature.
See also:
handling and storage
Prepared-stock stability
Prepared-stock stability describes the supported window after a material has been prepared for an in-vitro method. It is different from lyophilized stability and depends on matrix, container, and temperature.
See also:
handling and storage
BAC bacteriostatic water
BAC means bacteriostatic water, a preserved aqueous laboratory diluent. It should be distinguished from sterile WFI-grade water and from molecule-specific solvent systems.
See also:
handling and storage
Sterile WFI-grade water
Sterile WFI-grade water is sterile water prepared to a high purity grade for laboratory workflows. This glossary wording avoids route-of-use language while cross-linking to BAC bacteriostatic water.
See also:
handling and storage
Cold-chain shipping
Cold-chain shipping uses temperature-controlled packaging to protect material during transit. It should be read beside -20 C storage and receiving inspection.
See also:
handling and storage