Doxorubicin interactions with bovine serum albumin revealed by microdialysis with on-line laser-induced fluorescence detection at subpicogram level

Microdialysis as a sampling tool for the chemotherapeutic agent Doxorubicin

Doxorubicin is a chemotherapeutic agent used for more than fifty years to treat a great variety of cancers in both children and adults. Despite hereof, pharmacokinetic knowledge is almost solely based on systemic plasma concentrations. Microdialysis is a catheter-based pharmacokinetic sampling tool enabling simultaneous target site sampling of unbound molecules of interest. The aim of this study was to thoroughly evaluate the feasibility of applying microdialysis for sampling of Doxorubicin in both in vitro experiments and an in vivo setting. Doxorubicin relative recovery by gain and by loss was tested for different catheter types, perfusion fluids, concentrations and collection vials. Adsorption tests revealed polystyrene/santoprene vials to be the biggest contributor of unwanted adsorption between Doxorubicin and the microdialysis equipment, and confirmed LoBind Eppendorf tubes to be a suitable alternative. The methodological combination of polyamide membranes, saline as perfusion fluid and LoBind Eppendorf sampling tubes demonstrated no statistically significant differences for relative recovery by gain and by loss, and the relative recovery was also found to be concentration independent. We conclude, that a proper microdialysis set-up can be used to collect samples containing concentrations of the chemotherapeutic drug Doxorubicin in vitro and in vivo, which encourage future pharmacokinetic studies to evaluate current treatment regimens to find the most effective and least toxic anti-neoplastic treatment for the patients.

Self-assembled anionic and cationic Au nanoparticles with Au nanoclusters for the exploration of different biological responsiveness in cancer therapy

Self-assembly overcomes the biodegradation resistance of some traditional inorganic drug carriers. Herein, we prepared self-assembled Au nanocluster-based nanoparticles with different sizes and charges based on solvent- and cation-induced self-assembly nanotechnology as anti-cancer drug vehicles to solve the potential metabolism problems of solid gold nanoparticles. We also systematically explored the responsiveness of cancer cells to self-assembled Au nanocluster-based nanoparticles with different sizes and surface modified properties. We discovered that self-assembled nanoparticles inherited molecular-like properties of small-size Au NCs and exhibited an aggregation-induced emission (AIE) phenomenon with intense luminescence. Self-assembled Au nanocluster-based nanoparticles (Au NPs and cAu NPs) taking advantage of their size and positive charge exhibited better cell uptake than Au NCs. Encouraged by the excellent biological compatibility and cell uptake of these nanomaterials, we prepared drug-loaded nanomaterials by diffusion absorption and hydrophobic-induced embedding. cAu NPs@DOX showed an excellent anti-cancer effect owing to efficient cell internalization; Au NPs@DOX exhibited slow release of cargo drugs which might be significant to in vivo drug delivery. This work plays a crucial role in the rational design of self-assembled multifunctional gold-based nanoparticles in the application of nanomaterial-assisted multifunctional drug delivery systems (DDSs).

A Simple and Easy Method of Monitoring Doxorubicin Release from a Liposomal Drug Formulation in the Serum Using Fluorescence Spectroscopy

Formulation of a drug as liposomes facilitates its delivery to the disease target. Rightly, liposomes are gaining popularity in the medical field. In order for the drug to show efficacy, release of the encapsulated drug from the liposome at the target site is required. However, the release is affected by the permeability of the lipid bilayer of the liposome, and it is important to examine the effect of the surrounding environment on the permeability. In this study, we showed the usefulness of fluorescence analysis, especially fluorescence fingerprint, for a rapid and simple monitoring of release of an encapsulated anticancer drug (doxorubicin) from its liposomal formulation (DOXIL). Our result indicated that the release is accelerated by the existence of membrane permeable ions, such as tris(hydroxymethyl)aminomethane, and blood proteins like albumin. Hence, monitoring of doxorubicin release by fluorescence analysis is useful for the efficacy evaluation of DOXIL in a biomimetic environment.

Doughnut-shaped bovine serum albumin nanoparticles loaded with doxorubicin for overcoming multidrug-resistant in cancer cells

Traditional spherical albumin nanoparticles remain as the dominant shape of nano-carriers described in the literature at present, due to their simple desolvation method of synthesis. However, non-spherical shapes also show great promise as cancer drug delivery vectors. In this study, we report a novel synthetic strategy based on dimethyl sulfoxide (DMSO) addition during desolvation step, to produce doughnut-shaped bovine serum albumin nanoparticles (DBSA-NPs), while maintaining narrow size distributions and homogeneity. The characteristics such as size, polydispersity and doxorubicin loading of prepared DBSA-NPs in comparison with spherical ones were determined. The biodegradation of DBSA-NPs loaded with doxorubicin (Dox-DBSA-NPs) in the presence of trypsin enzyme was spectrophotometrically monitored directly based on doxorubicin release profile. The release profile was analyzed with different kinetic models and it was best fitted with Higuchi kinetics model. The anticancer effect of Dox-DBSA-NPs against lymphoblastic leukemia (MOLT-4) and multidrug resistant uterine sarcoma (MES-SA/DX-5) cell lines were also investigated and the results were comparable with doxorubicin loaded spherical BSA nanoparticles. These results showed the potential of Dox-DBSA-NPs as a novel and high potential nano-carrier for management of non-resistance and also multidrug resistant cancer cells.