The UAE Reference Library: Technical Specifications for Analytical Reagents

Each entry below states the compound's registry identifiers and molecular specification, describes its chain architecture and the structural features that govern its analytical behaviour, sets out the in vitro screening contexts in which it is used as a reference standard, and notes handling constraints arising from its specific chemistry rather than from general good practice.

Every numerical specification on this page — CAS registry number, molecular formula, molecular weight, purity specification and analytical method — is read at build time from the same identifier registry that generates the corresponding product page, the structured data and the certificate of analysis. There is no separately maintained copy, so the index cannot drift from the released documentation.

Where a CAS registry number is recorded as not applicable, the material is a multi-component blend, a dual-vial kit or a prepared aqueous diluent, none of which has a single registry number. No approximate or nearest-match number is substituted in those cases.

BPC-157 (Body Protection Compound-157) (also cited as Pentadecapeptide BPC-157, PL 14736): CAS Registry Number 137525-51-0; molecular formula C62H98N16O22; average molecular weight 1419.55 g/mol; sequence 15-amino-acid gastric pentadecapeptide; supplied as 10 mg of lyophilized material; stored at 2–8 °C; released against a 99.91% specification determined by HPLC; catalogue product code VL-BPC-157-10.

A synthetic pentadecapeptide of fifteen residues, derived as a partial sequence of a gastric protein and prepared by solid-phase synthesis. The chain carries no cysteine residues and therefore forms no disulfide bridges, which removes disulfide scrambling from its degradation profile and simplifies its chromatographic behaviour relative to cyclised peptides of comparable length. It is supplied as a lyophilized powder of white appearance.

Used in vitro as a reference standard for analytical method development and system-suitability work: establishing retention behaviour on reversed-phase columns, calibrating ultraviolet response at 214 nm, and serving as a characterised comparator in receptor-binding and cell-based screening assays reported in the peptide literature. Its well-defined mass makes it a convenient identity control in LC-MS method qualification.

Stable as a sealed lyophilized solid under standard cold storage. In aqueous solution the backbone amide bonds are subject to hydrolysis, so prepared stocks should be aliquoted and held frozen rather than maintained as a single refrigerated volume.

GHK-Cu (copper tripeptide-1) (also cited as Gly-His-Lys·Cu²⁺, copper peptide GHK): CAS Registry Number 89030-95-5; molecular formula C14H22CuN6O4; average molecular weight 403.92 g/mol; sequence Gly-His-Lys (copper complex); supplied as 50 mg of lyophilized material; stored at 2–8 °C; released against a 99.89% specification determined by HPLC; catalogue product code VL-GHK-CU-50.

A copper(II) complex of the tripeptide glycyl-L-histidyl-L-lysine, in which the metal centre is coordinated by the imidazole nitrogen of the histidine residue together with backbone nitrogen and terminal amine donors. The complex is the origin of the characteristic blue-green colour of the lyophilized solid, and it is a defining analytical feature: loss of colour indicates dissociation of the copper centre and therefore a change in the species present.

Employed in vitro as a metal-peptide complex reference standard, in coordination-chemistry method development, in spectrophotometric work exploiting the copper d-d absorption band, and as a characterised comparator in cell-culture screening assays reported for copper tripeptides. Frequently used to validate that an analytical method resolves the metallated complex from the free peptide.

The copper centre is pH-labile. Acidic conditions and strong chelating agents in the buffer matrix will strip the metal and convert the material to free GHK, which is chromatographically and spectroscopically distinct. Diluent composition should be confirmed before reconstitution, and colour change treated as a disqualifying observation.

GHK-Cu (copper tripeptide-1) (also cited as Gly-His-Lys·Cu²⁺): CAS Registry Number 89030-95-5; molecular formula C14H22CuN6O4; average molecular weight 403.92 g/mol; sequence Gly-His-Lys (copper complex); supplied as 100 mg of lyophilized material; stored at 2–8 °C; released against a 99.90% specification determined by HPLC; catalogue product code VL-GHK-CU-100.

The same copper(II) glycyl-L-histidyl-L-lysine complex supplied at higher fill mass for workflows requiring larger stock volumes or higher working concentrations. Chemically identical to the 50 mg presentation; the distinction is fill quantity only.

Used where a single reconstitution must supply an extended screening campaign or a higher-concentration stock, reducing the number of vial-opening events and therefore the number of moisture-ingress opportunities across a study.

As for the 50 mg presentation. The larger fill increases the case for immediate subdivision into single-use aliquots, since a larger stock volume otherwise invites repeated freeze-thaw cycling.

AHK-Cu (Ala-His-Lys copper peptide) (also cited as Ala-His-Lys·Cu²⁺): CAS Registry Number 174699-09-3; sequence Ala-His-Lys (copper complex); supplied as 100 mg of lyophilized material; stored at 2–8 °C; released against a 99.88% specification determined by HPLC; catalogue product code VL-AHK-CU-100.

A copper(II) complex of the tripeptide alanyl-L-histidyl-L-lysine, structurally analogous to the glycyl homologue with alanine substituted at the amino-terminal position. The additional methyl group alters hydrophobicity and consequently retention behaviour, which makes the pair useful as a resolution test for chromatographic methods intended to separate closely related copper tripeptides.

Applied in vitro as a structural analogue reference standard in comparative coordination chemistry and in method-development work where separation of closely related metallopeptides must be demonstrated.

Shares the pH lability of the copper centre described for the glycyl homologue. Chelating buffer components should be excluded from the diluent matrix.

Retatrutide (GLP-3 RT) (also cited as LY3437943, triple GLP-1/GIP/glucagon receptor agonist peptide): CAS Registry Number 2381089-83-2; molecular formula C172H265N43O55; average molecular weight 4113.64 g/mol; supplied as 10 mg of lyophilized material; stored at 2–8 °C · protect from light; released against a 99.91% specification determined by HPLC; catalogue product code VL-GLP3-RT-10.

A large synthetic polypeptide, substantially longer than the tripeptide and pentadecapeptide standards in this catalogue, prepared by solid-phase synthesis and supplied lyophilized. Its molecular mass places it at the upper end of the range routinely handled by standard reversed-phase methods, and it typically requires a shallower acetonitrile gradient than short peptides to achieve acceptable peak shape.

Used in vitro as a high-molecular-weight reference standard in receptor-binding assay development and as a system-suitability marker where a method must be demonstrated to perform across a wide mass range. Its charge-state envelope in electrospray ionisation is broad and well populated, which makes it a useful test article for mass-spectrometric deconvolution workflows.

Larger polypeptides are more susceptible to aggregation and to interfacial adsorption than short peptides. Reconstitute by directing diluent down the vial wall, avoid agitation entirely, and inspect for haze before every use. Working dilutions at low concentration should be prepared in low-binding vessels immediately before use.

Semax (ACTH 4-10 analogue) (also cited as Heptapeptide Semax, MEHFPGP): CAS Registry Number 80714-61-0; molecular formula C37H51N9O10; average molecular weight 813.87 g/mol; sequence Met-Glu-His-Phe-Pro-Gly-Pro; supplied as 10 mg of lyophilized material; stored at 2–8 °C; released against a 99.88% specification determined by HPLC; catalogue product code VL-SEMAX-10.

A synthetic heptapeptide comprising the sequence Met-Glu-His-Phe-Pro-Gly-Pro, an analogue of a corticotropin fragment extended at the carboxyl terminus by a Pro-Gly-Pro motif. The chain contains a single methionine residue at the amino terminus, which is the principal oxidation-sensitive site and the feature that most affects its analytical behaviour on storage.

Used in vitro as a short-chain reference standard in neuropeptide analytical method development, and as a defined test article in oxidation-stability studies where methionine sulfoxide formation is the monitored transformation.

The amino-terminal methionine is readily oxidised by dissolved oxygen and by trace transition metals, producing a sulfoxide with a distinct retention time. Protect from light, minimise headspace exposure, and prefer freshly prepared solutions where oxidation state must be controlled.

Oxytocin (also cited as OT, cyclic nonapeptide hormone): CAS Registry Number 50-56-6; molecular formula C43H66N12O12S2; average molecular weight 1007.19 g/mol; sequence Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly (disulfide bridge); supplied as 10 mg of lyophilized material; stored at 2–8 °C; released against a 99.91% specification determined by HPLC; catalogue product code VL-OXY-10.

A cyclic nonapeptide of the sequence Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly, closed by an intramolecular disulfide bridge between the cysteine residues at positions one and six. The resulting twenty-membered ring with a carboxyl-terminal tripeptide tail is the classic disulfide-cyclised peptide architecture, and the constrained conformation is directly responsible for its chromatographic and mass-spectrometric signature.

Used in vitro as a well-characterised cyclic peptide reference standard in method development, disulfide-integrity assessment, and as a comparator in binding studies reported in the peptide literature. The disulfide bridge makes it a standard test article for methods intended to distinguish cyclised from reduced linear forms.

The disulfide bridge is susceptible to reduction and to scrambling under alkaline conditions or in the presence of reducing agents. Reduced and scrambled forms are chromatographically distinguishable from the intact cyclic peptide. Exclude reducing species from the diluent and avoid alkaline matrices.

PT-141 (Bremelanotide acetate) (also cited as Melanotan II derivative, MC4-R agonist peptide): CAS Registry Number 189691-06-3; supplied as 10 mg of lyophilized material; stored at 2–8 °C; released against a 99.89% specification determined by HPLC; catalogue product code VL-PT141-10.

A synthetic cyclic peptide of the melanocortin structural family, supplied as the acetate salt and lyophilized to a white powder. The cyclic architecture confers conformational rigidity, which is reflected in narrow chromatographic peak shape relative to comparably sized linear peptides.

Applied in vitro as a melanocortin-family reference standard in receptor-binding assay development and as a characterised comparator in cell-based screening reported for cyclic melanocortin analogues.

Supplied as an acetate salt, so the nominal vial mass includes counter-ion mass. Where absolute molar accuracy is required, use the certified peptide content rather than the nominal label mass in the concentration calculation.

Melanotan II (MT-II) (also cited as MT2, cyclic α-MSH analogue): CAS Registry Number 121062-08-6; supplied as 10 mg of lyophilized material; stored at 2–8 °C; released against a 99.87% specification determined by HPLC; catalogue product code VL-MT2-10.

A cyclic heptapeptide analogue within the melanocortin structural family, closed through a lactam bridge rather than a disulfide. The lactam linkage is chemically more robust than a disulfide and is not susceptible to reduction, which distinguishes its stability profile from that of disulfide-cyclised peptides of similar size.

Used in vitro as a conformationally constrained reference standard, and in comparative method development alongside disulfide-cyclised peptides to demonstrate that a method resolves the two cyclisation chemistries.

The lactam bridge is stable to the reducing conditions that affect disulfide-cyclised peptides. Standard lyophilized storage and single-cycle aliquot management apply.

β-Nicotinamide adenine dinucleotide (NAD⁺) (also cited as NAD, oxidized diphosphopyridine nucleotide): CAS Registry Number 53-84-9; molecular formula C21H27N7O14P2; average molecular weight 663.43 g/mol; supplied as 1000 mg of lyophilized material; stored at 2–8 °C · protect from light; released against a 99.90% specification determined by HPLC; catalogue product code VL-NAD-1000.

β-Nicotinamide adenine dinucleotide in its oxidised form: a dinucleotide in which nicotinamide mononucleotide and adenosine monophosphate are joined through a pyrophosphate bridge. It is not a peptide and its analytical behaviour differs accordingly — detection is normally at 260 nm, where the adenine chromophore absorbs strongly, rather than at the 214 nm peptide-bond wavelength.

Used in vitro as a coenzyme reference standard in enzymatic assay development, in redox-couple work where the oxidised and reduced forms must be resolved and quantified, and as a calibration standard in chromatographic methods for nucleotide analysis.

The pyrophosphate bridge is hydrolytically labile, particularly under alkaline conditions, and the oxidised form is readily reduced. Prepare solutions fresh where redox state is analytically significant, and buffer near neutral pH.

L-Glutathione (reduced) (also cited as GSH, γ-L-Glutamyl-L-cysteinylglycine): CAS Registry Number 70-18-8; molecular formula C10H17N3O6S; average molecular weight 307.32 g/mol; supplied as 1500 mg of lyophilized material; stored at 2–8 °C · protect from light; released against a 99.91% specification determined by HPLC; catalogue product code VL-GLUT-1500.

A tripeptide of the sequence γ-L-glutamyl-L-cysteinylglycine, distinguished by an atypical peptide bond formed through the gamma-carboxyl of the glutamate side chain rather than its alpha-carboxyl. That linkage confers resistance to conventional aminopeptidase cleavage and is a structural feature of analytical interest in its own right. The free cysteine thiol is the dominant reactive site.

Used in vitro as a thiol reference standard in redox chemistry, in the calibration of thiol-quantification assays, and as a defined reducing agent in method development where the oxidised disulfide dimer and the reduced monomer must be chromatographically resolved.

The free thiol oxidises readily in air to the disulfide dimer, a distinct species with distinct chromatographic behaviour. Minimise headspace, prepare solutions immediately before use where the reduced form is required, and treat solution age as an analytical variable.

MOTS-c (Mitochondrial ORF of the 12S rRNA type-c) (also cited as Mitochondrial-derived peptide MOT-C): CAS Registry Number 1627580-64-6; supplied as 10 mg of lyophilized material; stored at 2–8 °C; released against a 99.90% specification determined by HPLC; catalogue product code VL-MOTC-10.

A short mitochondrial-derived peptide encoded within a mitochondrial ribosomal RNA reading frame, prepared synthetically and supplied lyophilized. Its short chain length gives it early elution on reversed-phase gradients relative to the longer peptides in this catalogue.

Used in vitro as a mitochondrial-derived peptide reference standard in analytical method development and as a characterised comparator in cell-based screening assays reported for this peptide class.

Standard lyophilized storage applies. Short peptides elute early on reversed-phase gradients and may require adjusted initial organic composition to achieve adequate retention and peak shape.

Three classes of catalogue item are deliberately excluded from the registry table above because they have no single chemical identity. Multi-component blends combine several distinct peptides in a defined ratio and are characterised component by component rather than as a single substance. Dual-vial kits supply two materials intended for separate reconstitution and carry a certificate for each component. Prepared aqueous diluents — sterile laboratory water and bacteriostatic laboratory diluent — are solutions rather than substances and are released against microbiological rather than chromatographic specifications.

For each of these, the certificate of analysis states the applicable specification and the method used to determine it, and the batch verification index records the outcome for the released lot. Assigning a CAS registry number to any of them would be a misstatement of what the material is, so none is assigned.