The various polymer-based nanocarriers are very attractive for in vitro and in vivo bioapplications. A new type of promising drug delivery systems for cancer tissues - poly(D,L-lactide) nanospheres stabilized with Cremophor EL and loaded with hydrophobic cyanines (IR-780 or ZnPc) or curcumin (CUR) were fabricated by the nanoprecipitation method [1]. Obtained Cremophor EL/PLA/water nanospheres demonstrated regular shape, low polydispersity (PdI<0.3) and high entrapment efficiency of selected cargo (over 90%). The size of those nanoconstructs below 130 nm are in the desired nanocarriers size range for tumor delivery, that is larger than the renal filtration cutoff and small enough for tumor penetration [2]. Low level of in vitro drug release from loaded nanospheres after long-time storage indicates their good stability. The half-life of nanocarriers in the circulation, and their biodistribution after parenteral administration are associated with the ability of plasma proteins adsorption. For these reasons the affinity of the obtained nanospheres for albumin as a major plasma protein was investigated in vitro. The binding of nanocarrier containing cyanine IR-780 with albumin immobilized in the wells of polystyrene plate occurred with lower efficiency than analogs loaded with ZnPc or CUR. The formation of albumin/nanosphere complexes was confirmed in 1HNMR DOSY experiments and similar differences of Cremophor EL/PLA/water nanospheres affinity to serum albumin were observed. The changes in diffusion coefficient values revealed that nanosphere-albumin complex dimensions were about twice higher than those for a free nanoparticle loaded with ZnPc or CUR.
References:
[1] Bazylinska U. et al., Colloid and Surf. A Physicochem. Eng. Aspects 2013, 8, 128-135;
[2] Solaro R. et al., Materials 2010, 3, 1928-1980.
Acknowledgement: the work was supported by Wroclaw Research Centre EIT+ within the project POIG.01.01.02-02-003/08
jadwiga.pietkiewicz@umed.wroc.pl
