AssayIndex

AX-2026-043701

MK-677 (Ibutamoren mesylate) · 500 mg declared · Bachem Holding (Suzhou) Co., Ltd. · lot BCH-2601-G7291

FAILVERIFIED
Report ID
AX-2026-043701
Compound
MK-677 (Ibutamoren mesylate)
Compound class
Non-peptide adjuncts
Supplier
BCH — Bachem Holding (Suzhou) Co., Ltd.
Batch / lot
BCH-2601-G7291
Declared label claim
500mg
Laboratory
Janoshik Analytical
Assay date
11 Mar 2026
Submitted
22 Mar 2026
Quarter
2026-Q1
Submitter
r.vermeulen
Sample provenance
Buyer-sourced
Section 1

Results

Measured against the index acceptance specification for the non-peptide adjuncts class. A specification is a decision the index made; a result is a measurement. See where each threshold came from.

ParameterMethodResultUnitIndex spec
PurityRP-HPLC, 30 min gradient, 214 nm97.97% area≥ 98.5FAIL
Total impuritiesRP-HPLC, sum of reported peaks2.03% area≤ 1.5FAIL
Largest single impurityRP-HPLC — spiroindane regioisomer0.98% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula624.2181DaNOT TESTED
Identity — observed monoisotopic massLC-MS, high resolution (ESI-TOF/QTOF)624.2187DaNOT TESTED
Mass accuracyobserved vs theoretical+1.0ppm± 10PASS
Total peptide contentby difference from the gravimetric mass balance79.76%w/wNOT TESTED
Target-compound contenttotal peptide content × purity78.14%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen649.26mg500 mg declaredNOT TESTED
Recovered target peptidegross fill × target content507.332mg500 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim101.5%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate4.13%≤ 10.0PASS
Counter-ion (mesylate)anion-exchange ion chromatography15.26%≤ 12.0FAIL
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.85%NOT TESTED
Endotoxinnot ordered on this submissionnot determined≤ 5.0NOT TESTED
Sterilitynot ordered on this submissionnot determinedno growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundWhite lyophilised cake, intactwhite to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureClear, colourless, no visible particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration4.412.5 – 8.0PASS
Retention time (observed)RP-HPLC, 30 min gradient14.03min13.86 ± 0.30 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.120.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²75,683≥ 20,000PASS
Resolution to nearest impurityvs free base (des-mesylate, −96 Da)0.19no index criterionREPORTED
Section 2

Chromatogram and peak integration

The figure is drawn from the table. It is not an independent illustration — if a number in the table changed, the trace would change with it.

02099419862978396 MK-677 (Ibutamoren mesylate)14.03 min · 97.97 % 14.475.83 same trace · ×50 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 05101520253035 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 30 min gradient, 214 nm. Drawn from the peak-integration table below: peak positions are the reported retention times, peak areas are the reported area percentages, peak widths follow the reported plate count of 75,683, and skew follows the reported asymmetry factor of 1.12. Baseline noise is seeded from the report ID and is illustrative. The lower panel is the same trace at a stated vertical expansion with the slow gradient drift subtracted, because at full scale a 0.98 % impurity against a 97.97 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1MK-677 (Ibutamoren mesylate) — main peak14.034,761,64697.97
2spiroindane regioisomer14.4747,6310.980.000
3sulfonamide hydrolysis product (+18 Da)13.1728,1900.58+18.011
4O-desmethyl metabolite analogue (−14 Da)13.5113,6090.28-14.016
5residual DMF (process solvent)5.835,3460.11-551.000
6free base (des-mesylate, −96 Da)14.073,8880.08-96.011
Closure check — purity + Σ impurities 100.00CLOSES

Reporting threshold 0.05 % area. Peaks below it are not reported and are therefore excluded from the total, which overstates purity by their sum — see peak integration.

Section 3

Mass spectrum and identity

Theoretical monoisotopic mass 624.2181 Da, computed from C27H36N4O5S · CH4O3S. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100250325400475550625700 [M+1H]1+625.23[M+2H]2+313.12 m/z Relative abundance (%)
Figure 2. ESI charge-state envelope, high-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 624.2187 Da. Sodium (+21.982/z) and potassium (+37.956/z) adducts are shown where the parent charge state exceeds 25 % relative abundance; they are adducts of the same molecule and are not impurities.
ChargeTheoretical m/zObserved m/zΔ m/zRel. abundance (%)
2+313.1163313.11660.000354.2
1+625.2254625.22600.0006100.0
Section 4

Gravimetric mass balance

Water, counter-ion, residual and total peptide content are exhaustive and mutually exclusive categories. They must account for 100 % of the cake mass. The index closes this to within 0.02 pp and the build asserts it.

ComponentDetermination%w/w of cake
WaterKarl Fischer4.13
Counter-ion (mesylate)ion chromatography15.26
Residual solvent + inorganic residueestimated0.85
Total peptide contentby difference79.76
Total100.00 CLOSES

Supplier certificate, as declared

The supplier's own figures for this lot, beside the independent measurement. Divergence is assessed against the batch median, not against this single report — see rule AX-R05.

FigureSupplier COAThis reportIndex note
Purity (% area)97.8497.97divergence -0.14 pp vs batch median
Total impurities (% area)2.162.03
Largest single impurity (% area)1.320.98
Water (%)2.04.13
Counter-ion (%)3.115.26
Peptide content (%w/w)97.679.76
Endotoxin (EU/mg)1.00not determined
Method stated on certificateYEScolumn, gradient and wavelength given
Section 5

Provenance and caveats

Where a sample came from changes the weight of the evidence. The index treats it as a first-class field.

Sample provenance
Buyer-sourced
Evidentiary weight
Strongest available evidence in this index.
Chain of custody
Retail purchase → submitter (ambient, 28 d) → laboratory (hand-carried, 9 d) → assay.
Assay date
11 Mar 2026
Submitted to the index
22 Mar 2026
Laboratory
Janoshik Analytical, Ostrava, Czechia
Method basis
30 min gradient · high-resolution MS
Verification status
VERIFIED
Section 6

Annotations 4

Signed technical comments from index contributors. Not a discussion forum — annotations question or contextualise the result, and the data team replies where a reply is warranted.

ms_confirm
Two instruments or it is not confirmed, and this record is one instrument. It is a good one instrument, and the index records it as confirmed rather than corroborated for that reason.
isotope_cluster
Nothing here rules out a positional isomer with the same formula. Mass cannot; only chromatography can, and the gradient length on this record is the relevant fact for that.
peak_integrator
Resolution to the nearest named impurity is reported on this record with no verdict attached, which is the correct handling. A threshold on that figure would penalise compounds for their own impurity profiles.
hplc_ola
A longer gradient buys resolution on close-eluting pairs at a linear cost in run time. Janoshik ran 30 min here; the reference method runs 30, and the difference is visible in this figure.
Section 7

Related records

Same batch — lot BCH-2601-G7291 n=7

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043697BCH-2601-G7291PeptideMeter2026-Q198.264.31Buyer-sourced1FAIL
AX-2026-043698BCH-2601-G7291Nordanalyt2026-Q197.673.9597.7Buyer-sourced1FAIL
AX-2026-043699BCH-2601-G7291PeptideMeter2026-Q198.093.9897.5Buyer-sourced1FAIL
AX-2026-043700BCH-2601-G7291Medutest2026-Q197.983.5989.1Buyer-sourced2FAIL
AX-2026-043702BCH-2601-G7291Medutest2026-Q198.413.7192.0Laboratory-retained1FAIL
AX-2026-043703BCH-2601-G7291Janoshik2026-Q197.974.1497.4Buyer-sourced1FAIL
Other recent MK-677 (Ibutamoren mesylate) records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041754FGPFGP-2604-K9878Janoshik2026-Q299.895.0693.8Buyer-sourced0FAIL
AX-2026-042619SWBSWB-2605-B6440Janoshik2026-Q299.303.05Buyer-sourced0FAIL
AX-2026-041756FGPFGP-2604-K9878Janoshik2026-Q299.624.4189.4Buyer-sourced1FAIL
AX-2026-041751FGPFGP-2604-K9878Janoshik2026-Q299.795.6988.7Buyer-sourced1FAIL
AX-2026-043676BCHBCH-2511-G7498Medutest2026-Q298.864.8199.6Buyer-sourced1FAIL
AX-2026-043678BCHBCH-2511-G7498Kestrel2026-Q298.743.73Buyer-sourced0FAIL
AX-2026-041753FGPFGP-2604-K9878Janoshik2026-Q299.935.7288.7Buyer-sourced1FAIL
AX-2026-043677BCHBCH-2511-G7498Janoshik2026-Q298.834.58Supplier-supplied0FAIL
Other recent BCH records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043691BPC-157BCH-2603-L7768Janoshik2026-Q398.665.12Supplier-supplied1MARGINAL
AX-2026-043693BPC-157BCH-2603-L7768PeptideMeter2026-Q397.825.2194.9Buyer-sourced0FAIL
AX-2026-043686BPC-157BCH-2603-L7768VendorInvestigate2026-Q397.645.27Buyer-sourced0FAIL
AX-2026-043695BPC-157BCH-2603-L7768Janoshik2026-Q397.615.42Buyer-sourced0FAIL
AX-2026-043726N-Acetyl Semax AmideBCH-2602-E8475Janoshik2026-Q397.899.67104.2Buyer-sourced0FAIL
AX-2026-043688BPC-157BCH-2603-L7768Janoshik2026-Q397.945.56Buyer-sourced0FAIL
AX-2026-043658BPC-157BCH-2603-G6644Janoshik2026-Q398.454.37101.8Supplier-supplied0PASS
AX-2026-043692BPC-157BCH-2603-L7768VendorInvestigate2026-Q397.605.61Buyer-sourced0FAIL