Abstracts Book - IMRC 2018

• SB2-O009
A CHEMICAL ANALYSIS OF CHITOSAN NANOPARTICLES
PREPARED BY TWO DIFFERENT METHODS AND THEIR BEHAVIOR
DURING THEIR ENZYMATIC DEGRADATION
Paula A. Mendez 1 , Carlos A. López 1 , Betty L. López 1 , Yuliana Monsalve 1
1 Universidad de Antioquía, Facultad de Ciencias Exactas y Naturales, Colombia.
Designing drug delivery polymeric systems is getting attention in pharmaceutical
research. Chitosan (CS) is a natural, biodegradable and biocompatible
polysaccharide with antibacterial activity, which presents amine and hydroxyl
groups that can be modified in order to get chitosan derivatives for specific
biomedical applications. However, the chemical modifications can change the
intrinsic properties of the polymer; thus, it is important to evaluate the degradation
and biocompatibility of this polymer when it has been used to prepare controlled
release systems. The aim of this work was to obtain nanoparticles (NPs) of CS by
different methods. (NPs) were prepared by self-assembly and ionotropic gelation
method using CS with different chemical modifications, in order to establish and
compare their enzymatic degradation behavior. The first system was prepared by
self-assembly low molecular weight chitosan (LMWCS) modified with oleic acid (OA),
CSL-OA, the particle size was 327.2± 4.3 nm. The amphiphilic character of this
polymer allowed to form self-aggregated spontaneously. On the contrary, medium
molecular weight chitosan (MMWCS) modified with OA does not form nanoparticles
by self-assembly. Thus, the second system was obtained by ionotropic gelation
method by cross-linking with sodium tripolyphosphate (TPP), (CSM-OA/TPP), the
particle size was 230.5 ± 5.0 nm. The third system also was prepared by electrostatic
interaction between CSL modified with polyethylene glycol (PEG) and succinic
anhydride (Suc), (CSL-PEG-Suc), and TPP, the particle size was 184.3± 5.0 nm. All
systems showed colloidal stability during 30 days. The enzymatic degradation study
developed during five days for these nanoparticles showed a degradation percent
of 4.1% for the CSM-OA/TPP system, 29.1% for the CSL-PEG-Suc/TPP and 33.9% for
the CSL-OA; it means that chitosan keeps its biodegradability after the modification.
The preparation method and molecular weight showed an important effect on the
degradation profile because the systems prepared by cross-linking with TPP and
MMWCS showed a slower degradation. The change in particle size was another
evidence of the enzymatic degradation. The results showed biodegradable systems
with potential application in drug delivery.
Keywords: Chitosan, nanocarriers, enzymatic degradation
Presenting authors email: mendez515@gmail.com