FAQ
How much sample is required for my analysis?
Each CHN analysis should include at least 5mg of transferable sample. Halogens depend upon the theoretical percentages expected.
| % expected | %Cl | %Br | %F | %O | %P | %I | %S |
| 1-5% | 25mg | 10mg | 20mg | 20mg | 4mg | 5mg | 30mg |
| 5-10% | 10mg | 5mg | 10mg | 10mg | 3mg | 4mg | 15mg |
| 10-20% | 5mg | 3mg | 10mg | 5mg | 3mg | 3mg | 8mg |
| above 25% | 4mg | 2mg | 10mg | 4mg | 2mg | 3mg | 8mg |
*All sample sizes are meant as transferable from the vial.
**If the sample’s consistency is sticky or static sensitive, additional sample is required.
Is it important to list Molecular Formulas?
It is important that samples include a molecular formula. This allows us to rule out interferences and select the optimal sample size for highest accuracy. If mistakes are made due to lack of input on this matter, retesting can be done at additional expense. Combustion aids are available at no additional charge and should be indicated on the Submission Form.
Can you provide RUSH service for my sample?
Yes, RUSH Service is available with a guaranteed 48 hour (M-F) turn around, for an additional charge. Please indicate RUSH on Sample Submission Form. Rush analyses is limited to limited quantities of CHN, Cl, S, I, or Br analysis. Please note that RUSH requested for F, P, or O analysis will be attempted, but is not guaranteed.
Do you handle air-sensitive samples?
We maintain a Nitrogen glove box at 40ppm of Oxygen. An additional charge per sample analysis is charged for glove box handling. It is important that samples are sealed adequately when shipped. Air sensitive samples must be transferrable. Due to techniques used, we cannot analyze phosphorus as an air sensitive substance. Drying is never able to be done on air sensitive samples.
Are there any specific types of samples that you do not handle?
Yes, due to the health and safety of personnel, we do NOT handle any compounds containing Osmium, Non-Depleted Uranium, or Thallium or with a high toxicity or strong stench. We do not handle any Finished Pharmaceuticals for release or Highly volatile liquid samples with boiling points of less than 40 deg C.
How do you perform the analyses?
CHN analysis is performed via combustion at 990 deg C with the elemental analyzer.
Sulfur, Chlorine, Bromine, and Iodine are done via flask combustion and subsequent titration.
Oxygen is preformed by pyrolysis at 1200 deg C and determined gravimetrically. (Unterzaucher Method). Oxygen determination is done on purely organic substances only (no metals or phosphorus present).
Fluorine is done by bomb digestion and subsequent determination by ISE.
Do you perform organic trace analysis?
For CHN analysis, our Lowest Detection Limit is 0.15% and our methods are accurate to 0.3%. For all other analysis types offered, the lowest detectable percentage is 0.4% (4000 ppm)
