Description
HIGH-PURITY SPECIALTY INGREDIENT
L-Selenomethionine Powder 98%
L-selenomethionine is supplied as a single-entity selenium amino acid at 98.0% by HPLC, released against a batch-specific certificate of analysis. Selenium-containing materials are dosed on their selenium content as well as on their assay, so both figures belong on the specification. It is an industrial raw material for further processing and is not a finished consumer product.
COA-Backed Specification
| Identity | L-Selenomethionine |
|---|---|
| Form and colour | Fine white to off-white crystalline powder |
| Assay | 98.0% |
| Method | HPLC |
| Particle size | 98% through 80 mesh |
| Loss on drying | <=5.0%; result 4.40% |
| Ash | <=5.0%; result 4.40% |
| Selenium content | Elemental selenium figure reported per batch |
| Isomeric form | L-isomer, confirmed on the certificate of analysis |
| Assay basis | Compound basis; the elemental basis is reported separately |
| Heavy metals | Within the limits of the approved specification |
| Microbiological limits | Within the limits of the approved specification |
| Representative batch | LXXD260615 |
| Manufacture date | 15 Jun 2026 |
| Shelf life | Two years when stored properly |
Representative values do not replace the current shipment COA.
Buyer Decision Guide
Agree the assay, the selenium content basis and the isomeric form before approval. Confirm whether the buyer’s specification is written on the compound basis or on the elemental selenium basis, because the same material reports a different figure on each and the two cannot be compared directly.
- Assay: 98.0% by HPLC, released against the batch COA.
- Elemental selenium content reported per batch.
- Isomeric form confirmed: L-isomer.
- Assay basis stated so it can be compared with the buyer’s specification.
- COA, specification sheet and safety data sheet accompany each shipment.
- Regulatory status, permitted uses and labelling are the buyer’s responsibility for the destination market.
How This Grade Differs
Selenomethionine is offered as the L-isomer and as the racemic mixture, and selenium is also supplied as selenite and selenate salts. The isomeric form and the selenium species both change the specification and the handling. These are separate products and should not be substituted without confirming the specification.
For a substitution review, compare botanical identity, plant part, assay target, analytical method, physical form and the current offered-batch COA.
Application Areas
- Tablet and capsule systems for mineral fortification
- Premix and dry-blend manufacturing
- Functional food and beverage systems
- Animal nutrition premix systems
Packaging and Delivery
- Evaluation sample typically 10-20 g, subject to stock
- Regular MOQ typically 1 kg
- 1 kg foil bag or 25 kg fibre drum with inner food-grade liner
- Custom packing and private-label options subject to confirmation
- Typical lead time 7-15 working days after deposit
Quality and Documentation
Representative batch LXXD260615 supports the specification table above. Use the cited record for preliminary comparison and request the offered-lot COA for final technical approval. Batch COA, specification sheet, agreed third-party testing and export documents are available for buyer verification.
Frequently Asked Questions
What specification defines L-Selenomethionine Powder 98%?
For L-Selenomethionine Powder 98%: 98.0%, tested by HPLC.
Which identity details must remain consistent?
For L-Selenomethionine Powder 98%: match L-Selenomethionine across the quotation, specification and offered-batch COA. The offered grade is 98.0%.
How is batch-specific approval completed?
For L-Selenomethionine Powder 98%: the page cites representative batch LXXD260615. Final approval requires the current lot’s identity, specification results and relevant dates.
What forms part of the technical review?
For L-Selenomethionine Powder 98%: do not assess 98.0% in isolation; particle size, moisture or drying data and market-relevant safety limits can also affect acceptance.
Are you a manufacturer or a trading company?
LongBio is Shaanxi Longsheng Biotechnology Co., Ltd., a direct manufacturer of botanical extracts and functional ingredients integrating R&D, production and export support. Factory review can be arranged by video or an on-site visit.
Can I request the current batch COA before ordering?
Yes. Request the applicable current or representative COA and compare product identity, method, limits and results before approving a purchase order.
What is the minimum order quantity?
The regular MOQ is typically 1 kg. An evaluation sample of 10-20 g can usually be arranged before a formal order, subject to stock.
Do you support custom specifications or packing?
Alternative assay targets, particle size, packing and private-label requirements can be reviewed case by case, subject to production feasibility and a revised written specification.
Request COA, Sample or Quotation
Send your target specification, application, order quantity, destination country and required test limits.
