Croscarmellose Sodium SR Granules are pharmaceutical-grade granulated material designed for formulation applications involving a sustained-release granule system containing Croscarmellose Sodium as a functional excipient. Croscarmellose Sodium is the sodium salt of cross-linked, partly O-(carboxymethylated) cellulose and is widely recognized as a pharmaceutical excipient. Its CAS Number is 74811-65-7.
The SR (Sustained-Release) designation refers to the release characteristics of the finished granule formulation rather than to Croscarmellose Sodium itself. Croscarmellose Sodium is primarily associated with disintegration functionality, so the sustained-release performance of an SR granule system depends on the complete formulation, controlling excipients, coating or matrix system, manufacturing process and validated dissolution profile.
Croscarmellose Sodium is a cross-linked polymer of sodium carboxymethylcellulose. The cross-linked structure gives the material functional properties that make it useful as a pharmaceutical excipient. USP defines Croscarmellose Sodium as the sodium salt of a cross-linked, partly O-(carboxymethylated) cellulose.
Croscarmellose Sodium is commonly used as a functional disintegrant in oral solid formulations. It can be incorporated into different formulation systems depending on the intended dosage form and manufacturing process.
The CAS Number associated with Croscarmellose Sodium is 74811-65-7.
Croscarmellose Sodium SR Granules are intended for applications where the granulated material forms part of a sustained-release formulation system.
A sustained-release granule system may be designed to provide controlled release over a defined period. The actual release mechanism may depend on the formulation matrix, polymer system, coating technology, granule structure and other formulation variables.
Therefore, the SR characteristics of the finished product should be established through appropriate dissolution and release testing.
Important characteristics of a sustained-release granule product can include:
The actual numerical specifications for these parameters should come from the approved SDP product specification.
Croscarmellose Sodium is primarily used as a functional disintegrant excipient. Its cross-linked cellulose structure contributes to water uptake and swelling characteristics.
For an SR formulation, the final release behavior should not be attributed solely to Croscarmellose Sodium. Instead, the complete formulation system should be evaluated to determine how the active ingredient and excipient components interact and how the granule system controls release.
Croscarmellose Sodium has established compendial quality requirements. The USP material includes controls for identification, pH, loss on drying, residue on ignition, degree of substitution, water-soluble material and settling volume.
The published USP specification gives a pH of 5.0–7.0 for the specified dispersion and loss on drying of not more than 10.0%.
The residue on ignition specification is 14.0–28.0% calculated on the dried basis, while the degree of substitution is 0.60–0.85 on the dried basis.
Granule physical characteristics can influence material handling, blending, segregation, coating and downstream processing.
For Croscarmellose Sodium SR Granules, relevant product-specific characteristics may include:
Particle Size: Actual SDP specification
Bulk Density: Actual SDP specification
Tapped Density: Actual SDP specification
Flowability: Actual SDP specification
Moisture: Actual SDP specification
Do not publish D10, D50, D90, density or flow values unless they are supported by SDP's actual specification or analytical data.
The most important product-specific characteristic for an SR granule system is its release profile.
Depending on the formulation, evaluation may include:
For example, if the approved specification establishes dissolution at specific time points, those exact time points and acceptance criteria should be published.
A generic value such as “NLT 80% at 12 hours” should not be inserted unless it is actually the approved specification for the product.
Quality control for the Croscarmellose Sodium component can include:
The USP-derived specification gives total aerobic microbial count NMT 1,000 CFU/g, combined molds and yeasts NMT 100 CFU/g, and absence of E. coli.
For the finished SR granules, additional product-specific controls may include particle size, moisture, assay, content uniformity and dissolution/release testing.
Croscarmellose Sodium SR Granules may be considered for:
The actual application should be determined according to the formulation design and validated manufacturing process.
Croscarmellose Sodium should be preserved in well-closed containers according to the USP material.
Finished SR granules should be stored according to their approved product specification and packaging requirements, with appropriate protection from environmental conditions that could affect moisture, granule integrity or release performance.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | 98.0% – 102.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.2% |
| Heavy Metals | NMT 10 ppm |
| pH (1% Solution) | 2.0 – 4.0 |
| Individual Impurity | NMT 0.5% |
| Water Content | NMT 1.0% |