Liposomal quercetin: evaluating drug delivery in vitroand biodistribution in vivo

Objective:The drug-loaded PEGylated nanomaterials have shown effective cell-killing in vitro,but to the best of authors' knowledge there have been no reports of successful drug delivery in vitroand in vivousing polyethyleneglycol-2000-distearoyl phosphatidyl ethanolamine (PEG2000-DSPE) nanomaterials loaded with unmodified drug molecules, such as quercetin (QUE). In this study, it remained an open question as to whether such formulations could prove effective in vitroand in vivo,and to study the distribution and clearance of PEG-DPSE-ylated lipid-based quercetin nanoliposomes (PEG2000-DPSE-QUE-NLs) as delivery vehicles for the anticancer drug in vitroand in vivo.Research design and methods:PEG-DPSE layers were attached to QUE-NLs, dispersed in aqueous media and characterized using TEM and HPLC/UV spectroscopy. Tumor cell killing efficacy was assessed in vitrousing MTT and trypan blue exclusion assays, and the distribution and clearance pathways, as well as repeated administration in rats, were studied by HPLC spectroscopy.Results:PEG2000-DPSE-QUE-NLs were efficiently dispersed in aqueous media compared with controls, and PEGylated (PEG2000-DPSE) NLs were found to be effective drug delivery vehicles when simply loaded with QUE. The plasma QUE concentration decreased significantly (p < 0.05) after repeated administration of PEG2000-DSPE liposomal QUE. There was a slight ABC phenomenon with the PEG2000-DSPE-modified QUE liposomes.Conclusion:The QUE/PEG2000-DPSE formulation was more effective than QUE in vitroon inhibiting the growth of glioma cancer cells. This work demonstrates that nanomaterials (PEG2000-DPSE) are effective drug delivery vehicles in vivoas tumor-targeted drug carriers.