AssayIndex

GLBI-2512-S8068

L-Carnosine · 500 mg declared · GL Biochem (Shanghai) Ltd. · manufactured 27 Dec 2025

CHARACTERISED
Lot code
GLBI-2512-S8068
Supplier
GL Biochem — GL Biochem (Shanghai) Ltd.
Compound
L-Carnosine
Compound class
Short bioregulator peptides
Declared label claim
500mg
Manufacture date
27 Dec 2025
Index quarter
2026-Q2
Independent assays
9
Laboratories involved
PeptideMeter, Medutest, Janoshik
Provenance mix
Buyer-sourced ×7 · Supplier-supplied ×1 · Laboratory-retained ×1
Section 1

Reproducibility across independent tests

Every report below is an observation of the same physical material. What they disagree about is measurement; what they agree about is the lot. The size of the disagreement is compared against what the contributing laboratories' own repeatability figures predict.

Independent assays 9
Median purity 99.60% n=9
Spread (max − min) 0.77pp n=9
Standard deviation 0.246pp n=9
98.198.498.799.199.499.7100.1This lot (GLBI-2512-S8068)This lot (GLBI-2512-S8068): Q1 99.46, median 99.60, Q3 99.62, n=9outlier 99.16outlier 99.93n=9All L-CarnosineAll L-Carnosine: Q1 99.21, median 99.58, Q3 99.84, n=26outlier 98.20n=26 Purity (% area)
Figure 1. This lot's independent purity results against the whole L-Carnosine record set in the index. The vertical line is the index acceptance specification for the short bioregulator peptides class, 99.0 % area. A narrow box on the top row against a wide box on the bottom row is the ideal reading: it means the disagreement between lots is much larger than the disagreement within this one.
Section 2

Member reports 9

Every report the index holds on this lot. Each is a page carrying its own chromatogram, mass spectrum, mass balance, provenance and caveats.

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043188GLBI-2512-S8068PeptideMeter2026-Q299.628.43Buyer-sourced0PASS
AX-2026-043189GLBI-2512-S8068Medutest2026-Q299.608.49Buyer-sourced0PASS
AX-2026-043190GLBI-2512-S8068Janoshik2026-Q299.468.66Buyer-sourced0PASS
AX-2026-043191GLBI-2512-S8068Janoshik2026-Q299.608.38Buyer-sourced1MARGINAL
AX-2026-043192GLBI-2512-S8068Janoshik2026-Q299.288.71106.8Buyer-sourced0PASS
AX-2026-043193GLBI-2512-S8068Medutest2026-Q299.938.4891.9Buyer-sourced0PASS
AX-2026-043194GLBI-2512-S8068Janoshik2026-Q299.628.1690.4Buyer-sourced0PASS
AX-2026-043195GLBI-2512-S8068Janoshik2026-Q299.168.6989.4Laboratory-retained1MARGINAL
AX-2026-043196GLBI-2512-S8068Medutest2026-Q299.868.6091.5Supplier-supplied0PASS
Section 3

By laboratory

Where more than one laboratory assayed this lot, the difference between them is a paired observation of their relative bias — the same material, the same time window, different instruments. Those pairs are what the index's bias estimates are built from.

LaboratoryReportsPurity results (% area)MedianGradientPublished bias (pp)Bias-adjusted
PeptideMeter199.6299.6228min-0.0599.67
Medutest399.60, 99.93, 99.8699.8625min+0.0899.78
Janoshik599.46, 99.60, 99.28, 99.62, 99.1699.4630min+0.0099.46

This lot contributes 3 paired comparisons to the inter-lab analysis.

Section 4

The supplier's certificate for this lot

One number the supplier wrote, beside the median of the numbers other people measured on the same physical material. That comparison is only available because the index groups by lot.

FigureSupplier COAThis reportIndex note
Purity (% area)99.4599.62divergence -0.15 pp vs batch median
Total impurities (% area)0.550.38
Largest single impurity (% area)0.290.22
Water (%)7.18.43
Counter-ion (%)not statedN/A
Peptide content (%w/w)not statednot determined
Endotoxin (EU/mg)0.33not determined
Method stated on certificateYEScolumn, gradient and wavelength given
Section 5

Impurity fingerprint

The named impurities reported across this lot's assays, with how consistently each was seen. A fingerprint is what allows two lot numbers held by different companies to be identified as one bulk.

Named impurityReported inMedian % areaRange
D-carnosine epimer9 / 90.220.04–0.42
β-alanine (−137 Da)8 / 90.070.03–0.13
anserine (methylcarnosine, +14 Da)8 / 90.090.03–0.40
free histidine (−71 Da)8 / 90.040.03–0.07
Section 7

What this rollup does not establish