Resumo:
Nowadays, many research related tovhybrid materials and the advances in
Reversible-Deactivation Radical Polymerization (RDRP) techniques have enabled the
development of responsive materials. These compounds respond to specific stimuli
and have been integrating many research projects involving different drug delivery
systems. In particular, hybrid conjugates based on protein−polymer have been
integrating different formulations already approved by the Food and Drug
Administration. In general, protein-polymer conjugates can increase the drug plasmatic
half-life, altering the drug biodistribution profile and opening the possibility to reduce
the dose administrated, which is a relevant advantage for patients. In this work, poly
(N-vinylcaprolactam) (PNVCL) and poly (2-dimethylamino-ethyl methacrylate)
(PDMAEMA) polymers were grafted to the surface of a protein model, the bovine
serum albumin (BSA), by grafting-from approach, using the Atom Transfer Radical
Polymerization (ATRP) technique. Firstly, a macroinitiator (BSA-MI) was successfully
obtained and characterized by Sodium dodecyl sulfate polyacrylamide gel
electrophoresis and Matrix-Assisted Laser Desorption Ionization Time of Flight Mass
Spectrometry by modifying lysine groups present in the BSA. Then, the BSA-PNVCLco-PDMAEMA hybrid was synthesized using BSA-MI as an initiator. The conjugate
production was evaluated, revealing significant changes in the nanoparticles’
molecular mass and zeta potential . Additionally, it is demonstrated that altering the
monomers' ratio can further adjust the lower critical solution temperature (LCST) of the
protein-polymer conjugates. The results indicate the obtaining of a BSA-PNVCL-coPDMAEMA able to encapsulate approximately 1.9 mg of cisplatin for each 1 mg of the
hybrid, making this conjugate a very promising hybrid material with desirable properties
for a possible application in smart drug delivery systems.