Sample Requirements

General Requirements

Sample accessibility

Please ensure that the amount, which is required for a specific analysis, is actually accessible by our analysts. For instance: 2 mg of an oily substance which is spread over the interior of the sample vial does not correspond to 2 mg of analysis ready substance. In these instances, the sample amount needs to be increased to ensure access to the required 2 mg. 

On the other hand, freeze dried products are easily accessible, and usually, the amount stated on the vial is quantitatively accessibly by our analysts. However, it is good practice to provide surplus substance for e.g. reanalysis purposes and comfort of use in our laboratories.

Please review our “Sample amount table” for required sample amounts.

Sample homogeneity

Reproducibility and accuracy of our results strongly depend on factors such as sample homogeneity. Pronounced discrepancies between e.g. two duplicate values could arise from poor sample homogeneity. For instance: the sample is partially crystalline and partially in powder form. The two, very different, macroscopic form could lead to very different analytical outcomes, as one form might enclose residual solvents tightly.

Sample Amount

Method

Amount [mg] Single analysis

Amount [mg] Duplicate analysis
A.0.1.Enantiomeric purity by GC-FID

2

4
A.0.8. Enantiomeric purity by HPLC-UV

2

4
A.0.3. Enantiomeric purity by GC-MS – free amino acids/derivatives

3

5
A.0.3. Enantiomeric purity by GC-MS – peptides

4

8
A.0.10. Enantiomeric purity – enhanced accuracy double analysis

-

4
A.0.4. Quantitative determination; incl. determination of blind values

3

6
A.0.4.0. Quantitative determination excl.   determination of blind values

2

4
A.0.6.3. Amino acids as contaminants

8

-
C.26.1. Residuals of solvents (in duplicate)

3

5
C.27.1. Counter ions (in duplicate)

2

3
C.28.1. Water (in duplicate)

2

3
C.32. Determination of anions in duplicate via IC 

-

4
X.0.8. sequencing using HR-MS

2

-
X.0.8.1. Molecular weight

1

-

Sample Containers and labelling

Container

Please ensure that the sample is contained in a suitable vessel. For instance: 

  • Sample vial has to be tightly sealed (e.g. crimped lid) if volatile substances like residual solvents or water need to be determined
  • Vessel size should match the amount of sample. Recovery of sample becomes increasingly challenging with unnecessarily large vessel.
  • Packaging should account for vessel material e.g.: glass vials demand for shock absorbent padding.

Labelling

  • Please ensure that the sample vial itself is properly labelled. We do not accept unlabelled vials packed in labelled plastic bags.
  • Labelling should be resilient, permanent and contain all necessary information for unequivocal sample identification (e.g. name, lot#, batch#,…). Please avoid handwritten labels. 

Sample Characterization

Chemical Structures

Generally, including a structural drawing with your order form accelerates order processing and choice of appropriate analyses. This is especially the case, if your analyte contains non canonical amino acids. Structures can be included as high resolution image or, ideally, as digital file such as. *.mol.,*.skc, *.rxn, *.chm *.cdx, *.mst, *.rpt or *.wmf.

Nomenclature

Please use the amino acid naming convention defined by IUPAC or any other commonly used nomenclature. Proprietary naming needs to be either deciphered into IUPAC conforming lettering or ideally accompanied by a chemical structure. 

Additional characterization

A more detailed sample characterization could be necessary. Required information is listed with each detailed method description – e.g.: 

  • Amino acid sequence
  • Presence and type of protecting groups
  • Expected peptide content
  • Identity of excipients
  • Sample solubility
Inquiry & Ordering