Solubility enhancement and application of cyclodextrins in local drug delivery

Cyclodextrins (CDs) have been used in many pharmaceutical formulations as their constitution and inherent shape present advantages for drugs with poor aqueous solubility and low bioavailability. Because CDs can act as drug carriers by forming inclusion complexes to conjugate with many drugs, they have been applied in many drug delivery systems and can be used to develop new strategies. The objectives of this review are to describe the role of CDs in local administration, the ways in which CDs are used, and relevant studies currently underway. The basic structure and characteristics of CDs, as well as the mechanisms used to formulate inclusion complexes to solubilize drugs are also described. Several studies have been conducted to investigate the use of CDs and most have shown improvements in drug solubility and bioavailability. CDs show potential not only in the pharmaceutical industry but also in a variety of applications, and further research into the use of other drug carriers is therefore necessary.