How to choose a calcium phosphate phase for your indication

Choosing a calcium phosphate (CaP) phase is rarely about “the best material” and almost always about matching resorption, handling, and manufacturing constraints to your device concept. Below is a practical framework to compare α‑TCP, β‑TCP, HA, and TTCP/OCP systems in a way that survives scale‑up and supplier changes.

In practice, teams usually pick a phase based on a few constraints: whether the device must set in situ, how fast the material should resorb (relative to healing), and what your manufacturing line can reliably reproduce. The table and checklist below are meant to make those tradeoffs explicit.

Start with the workflow (not the chemistry)

• If you need a setting reaction (cement), focus on α‑TCP/TTCP‑based systems and the liquid phase, not only powder phase names.
• If you are making a non‑setting filler or composite, processing compatibility and PSD often dominate performance and reproducibility.
• For coatings or surface modification, phase purity plus morphology and dispersion behavior matter more than a single “purity” number.

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

Quick comparison: common phases in OEM programs

• α‑TCP: reactive and often used in setting systems; sensitive to moisture and processing history.
• β‑TCP: slower resorption than α‑TCP in many contexts; often used as a resorbable filler or as a component in composites.
• Hydroxyapatite (HA): typically more stable/less resorbable; widely used where long-term phase stability is desired.
• TTCP / OCP combinations: used in cement-like systems and can be tuned via formulation and processing.

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

Decision matrix you can actually use

Rule of thumb: if a parameter affects your process, include the method and sample prep in the spec. That single line saves weeks later.

Common pitfalls we see during transfer & scale‑up

• PSD mismatch: a new supplier uses a different measurement method and your ‘same PSD’ becomes a different powder in reality.
• Moisture/handling drift: especially for reactive phases; packaging and storage can change behavior before it reaches your line.
• Phase identity assumptions: names like “HA” hide large differences in morphology and agglomeration.

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

What to ask your supplier (minimum viable spec)

• PSD range + measurement method + dispersion assumptions.
• Moisture handling and packaging expectations (especially for reactive phases).
• Lot-to-lot variability expectations (ranges), not just a single typical value.
• Documentation scope: typical values for evaluation vs full COA for production.

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

If you want a recommendation

• Tell us your device concept, target handling, and your manufacturing constraints. We’ll propose a phase/system and a practical spec that’s easy to qualify.

Tip: if you’re unsure which bullet is critical, tell us your process step that fails (feeding, mixing, viscosity, setting). We’ll map the failure mode to the right spec controls.

Example spec snippet (copy/paste)

• Product: [phase/form factor]
• Particle size (PSD): [range] — Method: [laser diffraction / sieve / DLS], dispersion: [settings]
• Moisture: ≤ [x]% — Packaging: sealed, moisture-protected
• Documentation: Typical values for evaluation; Full COA for production lots on request
• Lot-to-lot variability: [acceptable ranges] for PSD/moisture/other critical items

Talk to us

Email info@kannrybio.com or use the contact form to discuss your target spec and stage (evaluation vs production). We can recommend a suitable grade and documentation scope.