April 17, 2024
Microcrystalline Cellulose

Microcrystalline Cellulose: A Unique and Versatile Excipient

Microcrystalline cellulose (MCC) is considered one of the most widely used excipients in the pharmaceutical industry. As an excipient, MCC serves multiple functional purposes in drug formulations and bring several benefits to finished drug products. This article discusses key aspects of MCC including its sources, production process, physico-chemical properties, functionality and various applications in pharmaceutical formulations.

Sources of MCC

MCC is produced from cellulose, a natural polymer found in abundant amounts in wood pulp and non-woody plants. Cellulose is the major constituent of plant cell walls and cotton. The primary commercial sources of cellulose used for MCC production are wood pulp and cotton. Other minor sources include straw, bagasse and microbial cellulose. The highly pure alpha cellulose extracted from these natural sources undergoes further processing to produce MCC.

Production of MCC

MCC is produced through an acid hydrolysis process where Microcrystalline Cellulose is treated with mineral acids like sulfuric acid. This leads to the cleavage of beta-glycosidic bonds between the glucose units of cellulose chains. The partially hydrolyzed cellulose obtained is then washed, filtered and dried. The process results in deposition of fine crystalline particles of pure cellulose. Further jet milling is done to obtain powdered MCC with uniform microscopic particle size in the range of 20-200 μm. Strict quality control is maintained during production to ensure consistency in properties between different MCC grades.

Physico-chemical Properties

Some important physico-chemical properties of MCC that contribute to its functionality include:
– Crystalline, porous, bulky particles that provide volume-filling capabilities.
– pH neutral and chemically inert nature safeguard stability of medicaments.
– High porosity (up to 90%) and surface area (15-30 m2/g) facilitating adsorption characteristics.
– Excellent flow and compressibility properties for tableting.
– Low moisture content (<0.5%) preventing caking or lumping.
– Insoluble in water and gastrointestinal fluids.

Funtionality in Pharmaceutical Formulations

As an excipient, MCC provides multifunctional benefits across various oral and parenteral dosage forms. Some key functional roles of MCC include:

Binder: Adds cohesive strength and processability to powder blends. Improves tableting characteristics in direct compression formulations.
Diluent: Acts as a major filler-diluent in tablets increasing bulk weight at low costs.
Disintegrant: Provides rapid disintegration of tablets due to wicking and swelling properties upon water absorption.
Glidant: Improves flow characteristics and uniform mixing of powders during manufacturing.
Adsorbent: Readily adsorbs drugs, flavors, pigments, preservatives etc enhancing stability and shelf-life.
Bulking agent: Increases viscosity and volume of suspensions, creams, ointments etc without affecting drug bioavailability.

Applications

Some major applications where MCC finds extensive usage include:
Tablets: Used as binder, diluent or disintegrant in multiple therapeutic categories like analgesics, anti-infectives etc.
Capsules: Improves flow properties of powders filled in hard and soft gelatin capsules.
Sustained release dosage forms: Provides slowed drug release when compression coated on pellets or granules.
Parenterals: Acts as bulking agent and adsorbent in injections, lyophilized products and ointments/creams.
Cough syrups, suspensions and emulsions: Provides appropriate viscosity and stability.
Other uses: Found in veterinary, nutraceutical and food supplement products as well.

MCC has become a gold standard pharmaceutical excipient used extensively across varied dosage forms. Its unique physico-chemical properties and multifunctional role confer significant advantages to formulation development and large-scale manufacturing. With wide availability at low costs, consistency and established safety, MCC will continue to be widely preferred for innovator as well as generic drug products globally.

*Note:
1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it