Quick answer: Hydroxypropyl Cyclodextrin dissolves readily in water as a powder, but a clear finished phase still depends on guest loading and process order. The product page lists water solubility above about 50 g/100 mL at 25°C, MS 0.40–1.50, assay ≥98%, use about 0.5–5%, and water-phase processing up to about 60°C. Judging “soluble” from the powder alone misses the complexation step.
INCI and guest role are in Hydroxypropyl Cyclodextrin Carries Lipophilic Guests in Water. Native β-CD comparison is in Why Hydroxypropyl Beats Native Beta-Cyclodextrin in Serums.
What the solubility number means
Published tables often put unsubstituted β-CD near about 18 mg/mL water and HPβCD well above about 600 mg/mL. Cosmetics Add’s grade targets >50 g/100 mL at 25°C—more than enough for typical cosmetic water phases when you are only dissolving the carrier.
That number is the powder going into solution. It is not a promise that every lipophilic guest stays clear at every molar ratio. Guest size, polarity, stoichiometry, temperature, and competing solvents all move the haze line. If a pilot is cloudy after “the cyclodextrin dissolved,” the next check is guest load and complexation—not a claim that the HP-β-CD failed its solubility spec.
Use level in the finished formula is a separate band. The product page suggests about 0.5–5% HP-β-CD depending on guest concentration. That band is set by encapsulation need and aesthetics, not by pushing toward the powder’s maximum solubility.
What molar substitution changes on the lot
MS (molar substitution) is the average number of hydroxypropyl groups per glucopyranose unit. This grade lists 0.40–1.50. Literature HPβCD grades often sit near roughly 0.6 MS. Two COAs can share the INCI and still differ inside the allowed MS window. Write the band you will accept, and match the sample COA before you lock a production drum.
Loss on drying ≤5.0% and heavy metals ≤10 ppm sit on the same specification block. Moisture pickup after the drum is open can cake the powder; that is a handling check, not proof of the wrong INCI.
Process order on this product page
- Dissolve Hydroxypropyl Cyclodextrin in the water phase at room temperature or slightly elevated temperature (up to about 60°C) until the solution is clear.
- For encapsulation, premix with the lipophilic guest per the TDS—confirm whether your protocol premixes guest with CD before aqueous addition or introduces guest into already-dissolved CD.
- Check haze, odor, and guest assay after the complexation step—not after the carrier dissolve alone.
- Hold the chassis inside the listed pH window (about 3.0–10.0) unless the guest TDS demands a tighter range.
If haze remains, check guest load, MS of the lot, residual solvents, competing solvents or salts, and whether unsubstituted β-CD was issued under a vague PO. Do not raise HP-β-CD past the TDS band without a new stability and sensory check. Do not copy a percent from a pre-diluted guest–CD solution onto a neat ≥98% powder without recalculating guest-content math.
Retinol and other guests still need their own TDS
Encapsulation language around Retinol or fragrance oils does not move the vitamin or oil onto the cyclodextrin purchase line. Each guest keeps its own assay, light/heat limits, and regulatory pack. HP-β-CD is the carrier line on the COA.
What to send before the first sample ships
- INCI Hydroxypropyl Cyclodextrin; CAS line(s) you accept (128446-35-5 and/or 94035-02-6)
- MS band (for example 0.40–1.50) and assay (≥98.0% if required)
- Target use level and guest identity
- Confirm water-phase dissolve up to ~60°C and the premix order you will follow
- Whether you need a written complexation protocol with the sample
- Bench-sample pack size, plus COA, SDS, and TDS
Documents and a sample are on the product page. Match sample MS, water dissolve behavior, and guest clarity to the protocol you locked, then scale.
