Plan a trial for your application
Hydration state and potency review
Confirm anhydrous, monohydrate or dihydrate form before comparing lot results on an anhydrous basis.
Changing formulation suppliers
Request manufacturing site, impurity study and retest-period information. Relate moisture and potency to the validated formulation process.
Purchase specifications and incoming inspection
Include the intended grade or current specification in the enquiry. Use the table to compare selection criteria and inspection conditions. The specification agreed by both parties defines the contractual limits. USP · Azithromycin forms and potency definition ↗
| Property | Unit | Published or agreed specification | Test conditions and checks |
|---|---|---|---|
| Hydration state | Substance identity | USP lists anhydrous, monohydrate and dihydrate forms. | Verify the offered form, test reference and moisture content. |
| Potency | µg/mg | Cited USP monograph: 945–1030 on an anhydrous basis. | State the edition, measured moisture and conversion basis. |
| Related substances | % | Use the intended monograph and project limits. | Request the method, specified impurities and reporting threshold. |
When approving a sample, record the grade, methods, limits and specification revision. On receipt, match the packing lot number to the lot-specific COA and record the measured values and release decision.
Chemical identity
| Database entry | Molecular or composition formula | Molar mass |
|---|---|---|
| Azithromycin | C38H72N2O12 | 749.0 g/mol |
The values refer to the compound indicated. Confirm hydrate form, solution concentration and blend composition for the commercial grade.
From samples to commercial delivery
Packaging and receiving
Original packs must trace form, lot and manufacturing site. Request approved transit temperatures and the deviation procedure before receipt.
Storage and handling
If temperature or humidity controls apply, agree recording before quotation. Review seals and transport logs before release.
Sample and order lead times
State quantity and document-review milestones for R&D, validation and commercial batches. Confirm MOQ, quality release, dispatch and remaining time to retest at receipt.
Questions from the plant
How can COAs for different hydrate forms be compared?
Check manufacturing quality documents for the intended registration market and compare batch results from the same method.
Can two potency results under the same product name be compared directly?
Check as-received versus anhydrous basis and each lot’s measured moisture. Align potency units and conversion method before assessing the difference.
Report a delivery or batch issue
Include the order number, lot number from the package, label photos and inspection records for the affected lot. When retesting, check hydration state, assay or potency conversion, Related substances.
Request documents for your application
TDS · Technical data sheet
For grade selection and sample approval, specify the grade and revision required.
SDS · Safety data sheet
Specify the country or region of use and the required language.
COA · Certificate of analysis
Request a sample COA during supplier review. For incoming inspection, provide the actual lot number.