CHT Ceramic Hydroxyapatite Type II Support

CHT ceramic hydroxyapatite, (Ca₅(PO₄)3OH)₂, support is a leading purification medium for today's demanding downstream process industry. Its mixed-mode support offers unique selectivities and often separates biomolecules that appear homogeneous using other chromatographic methods. The diverse binding capabilities of CHT for host cell proteins, leached protein A, antibody dimmers and aggregates, nucleic acids, and viruses allow its use at any stage from initial capture to final polishing.

The robust properties of CHT ceramic hydroxyapatite improve efficiency, yield, and financial value through:

• Excellent capture at elevated flow rates, enabling processing at all scales
• Large capacity for high-titer upstream feedstocks
• Exceptional selectivity, allowing a two-step chromatographic process

Hydroxyapatite (Ca₅(PO₄)3OH)₂ is a form of calcium phosphate used in the chromatographic separation of biomolecules. Sets of five calcium doublets (C-sites) and pairs of hydroxyl-containing phosphate triplets (P-sites) are arranged in a repeating geometric pattern. Repeating hexagonal structures can be seen in electron micrographs of the material; space-filling models and repeat structure from Raman spectroscopy have also been constructed.

Two types of CHT ceramic hydroxyapatite, Type I and Type II, are available in three particle sizes, 20, 40, and 80 µm. Both types have elution characteristics similar to crystalline hydroxyapatite, but also have some important differences:

• Type I, sintered at 400°C, has a higher protein binding capacity and better capacity for acidic proteins
• Type II, sintered at 700°C, has a lower protein binding capacity, but offers better resolution of nucleic acids and certain proteins; it also has a very low affinity for albumin and is particularly well-suited for the purification of many species and classes of immunoglobulins

Regulatory support files are available upon request. Bio-Rad Laboratories is an ISO9001 registered corporation.