Nanospheres of chitosan and CdTe quantum dots for the
development of drug carrier systems
M. C. R. S. Bezerra1,2, D. P. L. A. Tenório1,2, C. R. Chaves1,2, T. M. Stamford1,2, Beate S.
Santos1,3, Adriana Fontes1, P. M. A. Farias1,2
1
Research Group on Nanostructures and Biological Interfaces – NIB, Universidade Federal de
Pernambuco, Recife, PE, Brazil
2
Graduate Program on Materials Science, PGMTR, Universidade Federal de Pernambuco,
Recife, PE, Brazil
Chitosan (Ch) nanospheres were prepared by reticulation with sodium tripolyphosphate
(NaTPP) with precursors of low molecular weight (MW) and high deacetilation degree (DD).
The obtained structures were compared by means of the influence of the distinct MW and DD
over the nanospheres size and surface charge distribution. The analyzed parameters aimed to
obtain the optimal configuration for the use of chitosan nanospheres labeled with fluorescent
cadmium telluride (CdTe) quantum dots as a model for the development of drug carrier
systems. The obtained structures were characterized by scanning and transmission electronic
microscopies (SEM and TEM, respectively), zeta potential measurements, particle size
distribution analysis (Figure 1) and spectroscopic methods (Figure 2). The obtained
nanospheres were highly luminescent (Figure 3) and presented smaller size and high values
for zeta potential for low molecular weighted chitosan. These features indicate the feasibility
of the obtained nanocomposite for its use as fluorescent drug carrier in physiologic medium.
180000
160000
Intensity / cps
140000
120000
100000
80000
60000
40000
20000
0
400
450
500
550
600
650
700
Wavelenght / nm
Figura 1: Size distribution of Chitosan
nanoparticles
Figura 2: Fluorescence emission spectrum
of Chitosan/CdTe nanocomposite
excited at 365 nm.
Figure 3:
Chitosan/CdTe
nanospheres.
Keywords: Chitosan nanospheres, drug carriers, nanocomposites.
Work supported by CNPq, FACEPE, CAPES, INFo,.
[1] H. C. Yang, W. H. Wang, K. S. Huang, M. H. Hon, Carbohydrate Polymers. 79, 176
(2010).
[2] K. S. Huang, W. J. Wu, J. B. Chen, H. S. Lian, Carbohydrate Polymers. 73, 254 (2008).
[3] H. Zhang, M. Oh, C. Allen, E. Kumacheva, Biomacromolecules, 5, 2461 (2004)
[email protected]; Avenida Professor Morais Rego, 1235. Laboratório de biofísica
química Professor Ricardo Ferreira, Centro de ciências da saúde, Recife, PE, Brazil