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Journal of Materials Science and Nanotechnology | Volume: 2
August 20-21, 2018 | Paris, France
Materials Science and Materials Chemistry
International Conference on
Antimicrobial activity of Vancomycin loaded in biomimetic hydroxyapatite and poly (Lactic acid)
microcapsules
Gertrud-Alexandra Paltinean, Aurora Mocanu, Gheorghe Tomoaia, Sorin Rapuntean, Ioan Petean, Ossi Horovitz
and
Maria Tomoaia-
Cotisel
Babes-Bolyai University of Cluj-Napoca, Romania
A
ny orthopaedic surgical procedure carries possible bone
infection risks, which might be prevented by using bone
cement based on combining pure hydroxyapatite, HAP or
biomimetic hydroxyapatite, bHAP, poly (lactic acid), PLA, and
antibiotic drugs, like vancomycin, VCM, for local drug delivery,
and thus overcoming the disadvantages of systemic antibiotic
therapy. The goal of the current study was to determine the
vancomycin antimicrobial ability by using hydroxyapatites,
HAPs, and PLA microcapsules that are biocompatible and
nontoxic. Our results show that the initial burst release
and total release of active VCM agent can be controlled
by using VCM/HAP/PLA or VCM/bHAP/PLA composites in
aqueous dispersions. Among bone cement, the biomimetic
hydroxyapatite, like multi-substituted hydroxyapatite with
Mg, Zn, Sr and Si, HAP-Mg-Zn-Sr-Si, has attracted increased
interest due to its osteoconductivity in vivo, thus opening the
new opportunities for orthopaedic surgical procedures. In the
current investigation, both pure HAP and HAP-Mg-Zn-Sr-Si were
prepared by wet chemical methods, without surfactants or
template molecules and characterized by XRD, FTIR, TEM, SEM-
EDX and AFM. The PLA microcapsules were synthesized and
morphologically characterized, by TEM, SEM and AFM. Then,
HAPs mixed with vancomycin loaded in PLA microcapsules
were synthesized and structurally characterized by XRD, FTIR,
TEM, SEM-EDX and AFM. Further, the vancomycin release into
the water dissolution medium was quantitatively measured
by UV-Vis spectrum, which is characteristic for vancomycin.
The vancomycin was released into the dissolution medium
from composite microcapsules, within of 4 weeks, compared
to vancomycin loaded in pure HAP, where drug release was
observed for only about 2 weeks. The release of vancomycin is
dependent of themicrocapsules (i.e. solid) anddissolution liquid
ratio and can be controlled with precision. The antibacterial
activities of aqueous dispersions of VCM/HAP/PLA or VCM/
bHAP/PLA composites were determined using the inhibition
zone assay. High level of inhibition zone was obtained for the
aqueous dispersions of both VCM/HAP/PLA and VCM/bHAP/
PLA composites, used individually, against four pathogenic
species: Staphylococcus aureus, Salmonella typhimurium,
Bacillus cereus and Micrococcus luteus. Additionally, a distinct
inhibition zone was clearly formed in methicillin-resistant
Staphylococcus aureus media for up to 3 weeks incubation,
for these composites. This approach can be used for further
development of controlled delivery systems of therapeutic
vancomycinmolecules,forbiomedicalapplicationsasthecoating
of metallic implants and as bone grafts in orthopaedic surgery.
Speaker Biography
Gertrud-Alexandra Paltinean graduated from the Faculty of Chemistry and Chemical
Engineering of Babes-Bolyai University (bachelor degree, master degree and doctorate).
Her activities are focused on the preparation and characterization of nanomaterials based
on multisubstituted hydroxyapatite and air pollution, using advanced technologies (UV-
Vis, lyophilizer, AFM, STM) from the Physical Chemistry Center where she is a member.
e:
pgertrud@gmail.com