The majority of commercially available drugs exhibit high efficacy but poor selectivity as they are unfortunately taken up by non-target cells. This often causes significant side-effects mainly associated with drug cytotoxicity. Cyclodextrins (CDs) have emerged as benign molecular carriers that improve the stability and bioavailability of administered drugs. The biocompatibility and biodegradability of these oligosaccharide nanocages make them very promising for in vivo administration. Many reports unveil additional interesting properties of CDs including their ability to overcome certain forms of multidrug resistance. Furthermore, because of their ability to effectively deliver photosensitising anticancer drugs they could be useful in photodynamic therapy (PDT), a new approach that utilises light-controlled delivery. The EU-funded CYCLON project developed a series of drug delivery nanosystems based on CDs. The design of the cavities facilitates high drug loading capacity, enhances targeting and overall improves permeability and retention. Diverse families of specifically modified CDs and nanoscale metal-organic frameworks (nanoMOFs) were synthesised with novel architectures fit for different purposes. One such system proved ideal for carrying the anti-HIV AZT drugs into HIV target cells, exhibiting efficient protection against viral infection. The researchers demonstrated that the nanocarriers could maintain the stability of the drug delivery during transfer of doxorubicin to cancer cells. Furthermore the scientists developed nanoparticles that respond to light for the delivery of E. coli targeted bacteriocides. Overall, the results obtained with the CYCLON drug delivery platforms were very promising, supporting their multifunctionality and versatility. In particular, optically controlled drug release has massive potential. Over 63 publications were produced by CYCLON members; additionally, a NanoPDT international conference was organized in Gothenburg, Sweden.
Drug delivery, cyclodextrins, HIV, doxorubicin