Overview
β-Cyclodextrin (β-CD) is a cyclic oligosaccharide derived from starch via enzymatic conversion. Its unique toroidal structure with a hydrophobic cavity and hydrophilic exterior enables it to form inclusion complexes with various molecules, enhancing their solubility, stability, and bioavailability. This property makes β-CD invaluable in pharmaceuticals, food, and cosmetics. First identified in the late 19th century, β-CD has gained industrial significance due to its non-toxic nature and versatility. It is produced commercially through the action of cyclodextrin glucosyltransferase (CGTase) on starch, followed by purification processes to achieve high purity.
Physical and Chemical Properties
β-Cyclodextrin is a white, odorless, crystalline powder with moderate solubility in water. Its molecular structure consists of seven α-D-glucopyranose units linked by α-1,4 glycosidic bonds, forming a truncated cone shape. The internal cavity (6.0–6.5 Å diameter) is hydrophobic, while the outer surface is hydrophilic due to hydroxyl groups. Thermal stability is moderate, with decomposition occurring around 260°C. β-CD is stable under acidic conditions but hydrolyzes in strong acids. Its ability to form complexes is pH-dependent, with optimal performance in neutral to slightly alkaline environments. The compound is non-hygroscopic but should be protected from prolonged exposure to moisture.
Main Applications
In pharmaceuticals, β-CD is widely used to improve drug solubility, mask unpleasant tastes, and enhance stability. Examples include ibuprofen-β-CD complexes for faster absorption and antifungal drugs like itraconazole. The food industry employs β-CD to encapsulate flavors, reduce bitterness, and extend shelf life by protecting sensitive compounds from oxidation. The cosmetics sector utilizes β-CD to stabilize fragrances and control the release of active ingredients. In industrial applications, it serves as a green catalyst and separation agent. Emerging uses include environmental remediation (e.g., pollutant removal) and nanotechnology (e.g., drug-loaded nanoparticles).
Safety and Storage
β-Cyclodextrin is classified as Generally Recognized as Safe (GRAS) by the FDA for food and pharmaceutical use. Oral toxicity is low (LD50 >5,000 mg/kg in rats), but high doses may cause gastrointestinal discomfort. Inhalation of powder should be avoided to prevent respiratory irritation. For storage, keep β-CD in sealed containers at room temperature (15–25°C) with relative humidity below 65%. Prolonged exposure to high humidity can lead to clumping. Bulk quantities should be stored on pallets in a well-ventilated area, away from incompatible substances like strong oxidizers.
B2B Procurement Guide
When sourcing β-cyclodextrin, prioritize suppliers with ISO 9001 certification and batch-specific certificates of analysis (CoA). Key specifications to verify include purity (≥98%), residual solvents (<0.5%), and microbial limits. Pharmaceutical-grade β-CD should comply with USP/EP monographs. For large-scale procurement, request samples to test compatibility with your application. Consider logistical factors like minimum order quantities (MOQs) and lead times. Pricing varies with purity and packaging; bulk purchases (e.g., 500+ kg) typically offer 10–20% cost savings. Establish long-term contracts with reliable suppliers to ensure consistent quality and supply chain stability.