Hydroxypropyl-γ-Cyclodextrin

Hydroxypropyl-γ-cyclodextrin (HPGCD) is a modified cyclodextrin, a cyclic oligosaccharide, with hydroxypropyl groups added to enhance its properties, primarily solubility and stability. It's used as a pharmaceutical excipient and in other applications to improve the properties of various molecules. 

Key Characteristics and Uses:

Chemical Structure:

HPGCD is a derivative of gamma-cyclodextrin, which is a cyclic molecule composed of eight glucose units. Hydroxypropyl groups are added to some of these glucose units, increasing its solubility and ability to form inclusion complexes. 

Solubility Enhancement:

One of the primary uses of HPGCD is to increase the solubility of poorly water-soluble drugs and other molecules, making them more bioavailable. 

Complex Formation:

HPGCD can form inclusion complexes with various molecules, encapsulating them and modifying their properties. This includes improved stability, controlled release, and altered solubility. 

Applications:

Pharmaceuticals: HPGCD is used as an excipient in drug formulations to improve drug solubility, stability, and bioavailability. 

Cosmetics and Personal Care: It is used to enhance the solubility and stability of active ingredients in cosmetics and personal care products, improving their performance and user experience. 

Food Industry: HPGCD can be used as a carrier for flavours, sweeteners, and colours, and it's also proposed for use with vitamins and polyunsaturated fatty acids. 

Research: HPGCD is used in research for various applications, including improving the solubility of curcumin for wound healing and studying its effects on cell function, particularly in relation to lysosomal storage diseases. 

Safety:

HPGCD is generally recognised as safe (GRAS) by regulatory bodies and is considered safe for use in cosmetics and oral consumption. 

In essence, HPGCD is a versatile molecule with the ability to modify the properties of other molecules, making it useful in a wide range of applications where solubility, stability, and controlled release are desired.