Encapsulation of methotrexate and cyclophosphamide in interpolymer complexes formed between poly acrylic acid and poly ethylene glycol on multi-walled carbon nanotubes as drug delivery systems.

By combining the advantage of multi-walled carbon nanotubes (MWCNTs) and interpolymer complexes, we synthesis a new carrier system consist of poly(acrylic acid)/poly(ethylene glycol)/carbon nanotube (PAA/PEG/CNT). Then, Methotrexate (MTX) and Cyclophosphamide (CPP) were loaded on PAA/PEG/CNT, and the physicochemical properties of nanoparticles characterized by Infrared spectroscopy (IR), Scanning Electron Microscopy (SEM), Thermo Gravimetric Analysis (TGA) and Nuclear Magnetic Resonance (NMR). In the second part after efficiency determination of loaded drugs, in vitro drug release study was examined with ultra violet spectroscopy (UV) in pH=7.4 buffer (human body range) and pH=4 buffer (pH of cancer cells), and fever temperature drug release kinetic was studied by different mathematical models.

Study on the interaction of Co (III) DiAmsar with serum albumins: spectroscopic and molecular docking methods.

This study was designed to examine the interaction of cobalt-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane-1,8-diamine (Co(III) DiAmsar) as a hexadentate ligand with human serum albumin (HSA) and bovine serum albumin (BSA) under physiological conditions in Tris-HCl buffer solution at pH 7.4. To this aim, at first, Co (III) DiAmsar was synthesized and characterized by nuclear magnetic resonance (NMR), and mass spectroscopy and then its interaction with HSA and BSA was investigated by means of various spectroscopic methods (Fourier transform infrared (FT-IR), UV-visible (UV-vis), fluorescence, and cyclic voltammetry (CV)) and molecular docking technique. The results of fluorescence titration revealed that the Co (III) DiAmsar strongly quench the intrinsic fluorescence of HSA and BSA through a static quenching procedure. Binding constants (Ka) and the number of binding sites (n∼1) were calculated using Stern-Volmer equations. The ΔG parameters at different temperatures were calculated. Subsequently, the values of ΔH and ΔS were also calculated, which revealed that the van der Waals and hydrogen bonding interaction splay a major role in Co (III) DiAmsar-HSA and Co (III) DiAmsar-BSA associations. The distance r between donor (HSA and BSA) and acceptor (Co (III) DiAmsar) was obtained according to fluorescence resonance energy transfer. The data obtained by the molecular modeling study revealed the surrounding residues of HSA and BSA around Co (III) DiAmsar.