Molecular weight chitosan

The selection depends entirely on the intended use: High Molecular Weight (HMW) chitosan (>300 kDa) is ideal for film-forming, wastewater treatment (flocculation), and textile finishing due to its high viscosity. Medium Molecular Weight (MMW) (100-300 kDa) is widely used in agriculture as a plant growth promoter. Low Molecular Weight (LMW) (<100 kDa) or Chitosan Oligosaccharides are preferred for biomedical and nutraceutical applications because of their superior water solubility and high bioactivity.

Beyond molecular weight, you must confirm the Degree of Deacetylation (DDA), which should ideally be above 85% for high-quality grades. Other critical parameters include viscosity (measured in mPa.s), ash content (<1%), moisture content (<10%), and pH level. For medical or food-grade sourcing, request a heavy metal analysis report to ensure lead, arsenic, and mercury levels are within safe limits.

For food-grade applications, ensure the supplier has ISO 22000 or HACCP certification. If exporting to the US, FDA GRAS (Generally Recognized as Safe) status is vital. For the EU market, compliance with REACH regulations is necessary. If the product is derived from shellfish, allergen labeling is a mandatory requirement for customs and end-user safety.

Most commercial chitosan is derived from shrimp or crab shells. However, for vegan or hypoallergenic markets, you should source fungal-based chitosan (derived from Aspergillus niger). Fungal chitosan offers better batch-to-batch consistency and avoids the seasonal fluctuations and allergen risks associated with marine-sourced raw materials.

The main risk is Customs clearance delays due to the product being a white powder. To mitigate this, ensure the supplier provides a comprehensive MSDS (Material Safety Data Sheet) and a Certificate of Analysis (COA) for every batch. On Made-in-China.com, prioritize Audited Suppliers who have experience with international chemical shipping protocols.

Use Secured Payment services offered by the platform to hold funds until shipping documents are verified. For large orders, hire a third-party inspection agency (like SGS or Intertek) to perform a Pre-Shipment Inspection (PSI) to test the actual Molecular Weight and DDA against the agreed specifications before the balance is paid.

Chitosan is hygroscopic (absorbs moisture), which can lead to clumping and degradation. Ensure the packaging includes double-layer PE bags inside fiber drums with desiccant packs. For shipping to humid climates, specify palletization with shrink-wrap to prevent moisture ingress during sea freight.

Chitosan prices fluctuate based on the raw material (shell) harvest seasons. Negotiate a tiered pricing structure based on annual volume rather than spot buys. Request a sample for lab testing (typically 50-100g) before committing to a bulk contract, and clarify if the quoted price is FOB (Free on Board) or CIF (Cost, Insurance, and Freight) to avoid hidden logistics costs.