What identity fields should a tesamorelin supplier Australia list on the CoA?
A research certificate of analysis is the identity artefact a purchasing laboratory retains after goods-in. For tesamorelin, the header should name the substance so that it can be reconciled with the vial label and the purchase order: the international non-proprietary name tesamorelin, any catalogue code, the historical synonym TH9507 where the supplier still prints it, the salt form (commonly acetate), and a sequence descriptor. Chemical evaluations identify tesamorelin as a synthetic human growth hormone-releasing factor analogue (PMID:17086939; PMID:19243281). The sequence line must therefore specify the 44-residue GHRH backbone together with the N-terminal trans-3-hexenoyl modification. A label that reads only “GHRH”, “GRF(1–44)” or “growth hormone-releasing factor” is chemically incomplete: unmodified GHRH(1–44), truncated fragments and hexenoylated full-length material are different entities and must not share a generic name.
The identity block should also carry a unique lot number, a manufacture or retest date in ISO format, the stated net peptide content or as-is mass basis, and the appearance of the lyophilised solid. Net peptide content, usually obtained from amino-acid analysis or nitrogen determination after correction for counter-ion and water, is not the same quantity as chromatographic purity. Both belong on the CoA, because a high HPLC area-percent can still correspond to a lower peptide mass fraction when acetate, residual water or process solvent are substantial. Methods used for identity should be named—typically reversed-phase HPLC retention-time correspondence to a qualified reference and an intact-mass match by electrospray or MALDI—rather than a bare “conforms” tick. Australian laboratories should query lots whose CoA omits method identification, the theoretical mass, or the observed mass. The report should identify the testing laboratory, the specification version and a unique document number so the file can be archived against the goods-in record.
Receiving staff should transcribe CoA fields into the inventory record before any aliquot is taken for method development. Discrepancies between the purchase-order description and the CoA sequence line are grounds to quarantine the vial. A tesamorelin supplier Australia that cannot produce this header block for the current lot is not ready for a research purchase, irrespective of advertised purity.
How does mass spectrometry confirm trans-3-hexenoyl GHRH identity?
Mass spectrometry is the orthogonal identity method that HPLC retention time cannot replace. Tesamorelin’s defining structural feature relative to human GHRH(1–44) is N-terminal acylation with a trans-3-hexenoyl group. On a CoA this should appear as a stated theoretical average or monoisotopic mass for the hexenoylated sequence, an observed mass from ESI-MS or MALDI-TOF, and a mass-error tolerance in daltons or ppm. Purchasing laboratories should test whether the reported observed mass is consistent with the hexenoylated 44-mer rather than with free-N-terminus GHRH(1–44). The hexenoyl modification contributes a mass increment of C6H8O, approximately 96 Da, relative to the unmodified peptide. A lot whose deconvoluted mass matches the unmodified backbone, or a truncated analogue, has failed identity regardless of HPLC purity.
Intact-mass spectra of a 44-residue peptide typically show a charge envelope under electrospray ionisation. The CoA or accompanying MS report should list the ionisation mode, the charge states used for deconvolution, and whether the mass refers to the free peptide or a stated salt. Multiply charged ions must be deconvoluted before comparison with theory; quoting a single m/z without charge state is not an identity result. Where a spectrum image is supplied, the receiving laboratory should check that the envelope is consistent with the claimed sequence and that a second envelope corresponding to a des-hexenoyl species does not dominate. Tandem MS of a proteolytic digest can localise the hexenoyl group to the N-terminal residue; b-ions beginning at the modified tyrosine are the relevant diagnostic. These measurements confirm that the lot is the named analogue rather than a related GHRH species (PMID:21283099; PMID:20872317). They do not replace a written sequence specification on the CoA, and they are not a substitute for lot-level HPLC related-substance data discussed below.
Which reversed-phase HPLC purity fields belong in a tesamorelin lot report?
Reversed-phase HPLC remains the standard purity assay for synthetic tesamorelin lots. A research CoA should report area-percent purity at a stated wavelength, commonly 214 nm or 220 nm, together with column chemistry (typically C18), gradient range, integration events and a related-substance profile. A headline purity percentage without a chromatogram, method identifier or peak table is not a complete result. Laboratories should look for a main-peak retention time, a system-suitability statement covering tailing factor and injection precision, and a diode-array peak-purity comment where DAD is used. Related substances expected in a hexenoylated 44-mer include deletion sequences, incomplete hexenoylation (des-hexenoyl GHRH(1–44)), methionine oxidation at residue 27, and residual protecting-group species from solid-phase synthesis.
Acceptance criteria belong on the specification. Typical research specifications set a minimum main-peak area-percent and maxima for any single unspecified impurity and for total impurities; the CoA should show measured values against those limits. If the supplier’s HPLC method differs from the receiving laboratory’s method, absolute retention times will not transfer. Identity then rests on mass spectrometry plus a method-stated relative retention time to a reference, not on a minute value copied from another laboratory. Chromatographic purity is not net peptide content: acetate, trifluoroacetate and water are poorly detected at 214 nm in many peptide methods, so a high HPLC purity lot still requires a separate content assay. Australian purchasing teams should request the numbered peak table, not only a percentage, and should archive the method version so later lots remain comparable on the same system.
How should Australian laboratories reconcile lot labels, CoAs and tracked dispatch?
Supplier evaluation in Australia is a documentation and logistics exercise as much as a chemistry exercise. Before a purchase order is released, the laboratory should require a CoA for the current lot or a complete template of the CoA fields, confirmation that the lot number on the vial label will match the CoA, and a packing list that repeats that lot number. ClaraScience positions research peptide supply around local Australian stock, tracked dispatch and batch documentation rather than around unverifiable paperwork. Receiving inspection should capture the vial label, the closure and the CoA, then record the lot in the inventory system against the analytical report number.
Traceability fails when a vendor reprints a generic CoA, when vials from different syntheses are sold under one lot number without a homogeneity statement, or when the CoA date is inconsistent with the stated manufacture date. Multi-vial orders should either share a single lot with a statement that all vials were filled from that lot, or carry per-vial identifiers cross-referenced to the parent lot. The purchase file should retain the supplier’s legal name, the research-use statement and the specification identifier. Tracked dispatch provides a chain-of-custody record from warehouse to goods-in; the consignment number belongs in the same file as the CoA. None of this documentation authorises human use. It exists so that an analytical result generated later can still be linked to a defined chemical lot. Laboratories that skip label-to-CoA reconciliation discover identity problems only after methods have been run, which wastes instrument time and breaks comparability between experiments.
What counter-ion, water and residual-solvent data complete the CoA?
A tesamorelin CoA that reports only HPLC area-percent is incomplete for quantitative research work. Synthetic peptides are typically isolated as acetate or trifluoroacetate salts and retain water. Counter-ion identity and approximate content—ion chromatography, fluorine NMR for trifluoroacetate, or a stated acetate assay—explain part of the mass on the laboratory balance. Residual trifluoroacetate can interfere with some spectroscopic research assays even when the peptide is used only as a reagent; laboratories that specify the acetate salt should see that form named on both the label and the CoA. Karl Fischer water content, or a loss-on-drying figure with a method reference, belongs alongside residual-solvent data where purification used acetonitrile, methanol or other process solvents. Headspace gas chromatography is the usual residual-solvent technique; the CoA should name the solvents sought and the reporting limit.
Appearance of the lyophilised cake, generally described as a white to off-white solid, is a weak identity test but a useful integrity check. Discoloration or collapse can indicate a process deviation or container failure and should trigger a query before the vial is opened for analysis. Solubility statements on a research CoA should be framed as sample-preparation guidance for HPLC or MS, for example dissolution in dilute acetic acid or aqueous acetonitrile for chromatography. Amino-acid analysis, where supplied, further constrains identity for a 44-residue chain and supports the net peptide content figure. Together these ancillary results let a purchasing laboratory convert milligrams of powder into an estimated peptide mass and judge whether the lot is suitable for a calibrated analytical method. They do not speak to any biological outcome and must not be read that way.
How do research buyers compare tesamorelin suppliers on documentation alone?
When two vendors both offer tesamorelin to Australian research buyers, the discriminating evidence is the completeness of the lot file, not the product name. A practical comparison matrix includes whether the sequence line explicitly includes the trans-3-hexenoyl N-terminus; whether intact mass and HPLC purity are both reported with methods; whether related-substance peaks are tabulated; whether salt form, water and residual solvent are addressed; whether lot numbers on labels, CoAs and dispatch notes match; and whether a research-use-only statement is unambiguous. Literature nomenclature treats tesamorelin as a growth hormone-releasing factor analogue and records the TH9507 designation (PMID:20554713; PMID:19243281), so a supplier that cannot map its catalogue name to that chemical identity is a poor documentation partner.
Price per milligram is interpretable only after the mass basis—net peptide versus as-is powder—is known. A cheaper lot with unstated water and acetate content can be more expensive on a peptide-mass basis. Independent verification, by retaining a vial for in-house HPLC-MS or sending an aliquot to a contract laboratory, should be budgeted for the first lot from a new supplier and after any change in manufacturing site or specification. ClaraScience’s research catalogue is intended to be evaluated on those documentary criteria: local stock, tracked dispatch, and batch reports that a receiving laboratory can file. Marketing adjectives such as “premium” without method-level data should be ignored. The correct purchase decision is the lot whose identity, purity and traceability records will survive an audit of the laboratory’s research quality system.
Order Tesamorelin with documentation
If this guide helped you evaluate Tesamorelin for laboratory work, the next step is documented supply: research-grade stock from Australian warehouses, Express tracked shipping, and batch documentation with every order.
Open the Tesamorelin card on the ClaraScience shop for current stock and add-to-cart, or request wholesale access when you need bulk restocks and tier pricing.
Frequently asked questions
Is tesamorelin identical to GHRH(1–44) on a certificate of analysis?
No. Tesamorelin is the N-terminally trans-3-hexenoyl analogue of the 44-residue GHRH sequence. A CoA that lists only GHRH or GRF(1–44), without the hexenoyl modification and without a mass consistent with that modification, does not establish tesamorelin identity. Require both the sequence descriptor and an intact-mass match before releasing the lot for research use.
What paperwork should accompany tesamorelin purchased for Australian laboratory research?
A lot-specific CoA, a packing list that repeats the lot number, and a tracked-dispatch record. The vial label must match the CoA for name, lot and salt form. File these with the purchase order and goods-in checklist. Local Australian stock shortens the documentation chain. The material remains research-use only.
Which orthogonal methods confirm tesamorelin identity?
Reversed-phase HPLC retention-time correspondence to a qualified reference plus intact-mass spectrometry against the theoretical mass of the hexenoylated 44-mer. Tandem MS can localise the N-terminal modification. Chromatographic purity without a mass match does not confirm identity, because a wrong sequence can still appear as a single HPLC peak.
How do HPLC purity and net peptide content differ on a tesamorelin CoA?
HPLC area-percent describes the distribution of UV-active related substances. Net peptide content estimates the peptide mass fraction after counter-ion and water. A laboratory converting weighed powder into a solution for an analytical method needs both figures. Neither result is a biological claim; both are chemical accounting fields.
How should two tesamorelin suppliers be compared before an Australian purchase?
Compare sequence descriptors (hexenoyl stated or not), intact-mass data, HPLC related-substance tables, salt and water fields, and whether vial labels match CoA lot numbers. Ignore unspecified grade language. Prefer suppliers who provide local stock, tracked dispatch and a complete batch file that a research quality system can archive.
References
- PMID:17086939 — Drug evaluation: tesamorelin, a synthetic human growth hormone releasing factor — Curr Opin Investig Drugs — 2006
- PMID:19243281 — Tesamorelin, a human growth hormone releasing factor analogue — Expert Opin Investig Drugs — 2009
- PMID:21283099 — Tesamorelin — Nat Rev Drug Discov — 2011
- PMID:20872317 — Growth hormone-releasing factor agonists for the treatment of HIV-associated lipodystrophy — Curr Opin Investig Drugs — 2010
- PMID:20554713 — Effects of tesamorelin (TH9507), a growth hormone-releasing factor analog, in human immunodeficiency virus-infected patients with excess abdominal fat: a pooled analysis of two multicenter, double-blind placebo-controlled phase 3 trials with safety extension data — J Clin Endocrinol Metab — 2010
Research use only
This article is provided for laboratory research and educational purposes only. Products referenced are not for human or veterinary use. ClaraScience makes no therapeutic, medical, or efficacy claims, and nothing here constitutes medical advice.
