Cyclodextrin complexes: Perspective from drug delivery and formulation

Abstract

Cyclodextrins (CDs) have been widely investigated as a unique pharmaceutical excipient for past few decades and is still explored for new applications. They are highly versatile oligosaccharides which possess multifunctional characteristics, and are mainly used to improve the physicochemical stability, solubility, dissolution rate, and bioavailability of drugs. Stability constant, factors affecting complexation, techniques to enhance complexation efficiency, the preparation methods for molecular inclusion complexes and release of guest molecules are discussed in brief. In addition, different CD derivatives and their pharmacokinetics are elaborated. Further, the significance of CD complex in aqueous solubility, dissolution and bioavailability, stability, and taste masking is explained. The recent advancement of CDs in developing various drug delivery systems is enlightened. Indeed, the potential of CDs by means of inclusion complex formation have widen the applicability of these materials in various drug delivery systems including ocular, osmotic, mucoadhesive, transdermal, nasal, and targeted delivery systems. Feasibility studies have been performed on the benefit of these cyclic oligomers as nanocarriers, a strategy that can modify the drugs with improved physicochemical properties. Studies also demonstrated the feasibility of CDs to self-assemble in the form of stable nanoaggregates, which may extend the scope of CDs in drug delivery to the continually expanding list of new drug entities.

Inclusion of the Phytoalexin trans-Resveratrol in Native Cyclodextrins: A Thermal, Spectroscopic, and X-Ray Structural Study

“…CDs are cyclic oligosaccharides containing six (α-CD), seven (β-CD), eight (γ-CD), or more α-1,4-linked α-D-glucopyranose units, obtained from the enzymatic degradation of starch by Bacillus macerans. Native CDs and their derivatives, such as hydroxypropyl-β-CD (HPβCD), sulfobutyl ether β-CD (SBEβCD), and dimethyl β-CD (DMB), which possess higher aqueous solubility, are widely used in the pharmaceutical field, owing to their ability to solubilize and stabilize drug molecules [16][17][18][19]. While applications for drug delivery are the ultimate goals, their viability is entirely dependent on the feasibility of isolating well-defined inclusion complexes that can be incorporated into appropriate formulations (e.g., tablets, capsules).…”

Emerging role of nanosuspensions in drug delivery systems

“…Other ingredients Complexing agent such as cyclodextrin derivatives have been explored for the improvement of dissolution and bioavailability of actives in nanosuspensions [31]. Nanosuspensions like coarse suspension might contain buffers, preservatives, osmotic agents, cryoprotectants, organoleptic agents, depending on the type, route and physicochemical nature of drug.…”

“…Nanosuspension technique is the only option available, when a drug molecule has many disadvantages such as inability to form salt, large molecular weight and dose, high log P and melting point that hinder them in developing suitable formulations. A major limitation of molecular complexation using cyclodextrin in pharmaceutical formulations is their inherent nature to increase the formulation bulk because of large molecular weight of complexing agent [31]. Nanosuspensions can solve such unique drug delivery issues associated with the active pharmaceutical ingredients (API) by retaining it in a crystalline state while enable them with increased drug loading during formulation development.…”

Ultrasound‐assisted green synthesis of Cu‐based complexes of β‐cyclodextrin and their SOD‐like activity

“…[8][9][10][11] The external surface of β-CD is hydrophilic owing to it containing hydroxyl groups, while its inner cavity is hydrophobic as it is lined with ether-like anomeric oxygen atoms. [8][9][10][11] The external surface of β-CD is hydrophilic owing to it containing hydroxyl groups, while its inner cavity is hydrophobic as it is lined with ether-like anomeric oxygen atoms.…”

“…On the other hand, in recent decades, β-cyclodextrin (β-CD) derivatives have been used in pharmaceutical applications for numerous purposes, including improving the solubility, stability, safety and bioavailability of drugs. [8][9][10][11] The external surface of β-CD is hydrophilic owing to it containing hydroxyl groups, while its inner cavity is hydrophobic as it is lined with ether-like anomeric oxygen atoms. This cavity makes it a useful tool, as it is capable of including guest molecules of different types.…”