DEVELOPMENT AND CHARACTERIZATION OF LIPOSOMES
CONTAINING CHLOROALUMINUM PHTHALOCYANINE FOR
LEISHMANIASIS TREATMENT
LOPES, S.C.A.1, TEDESCO, A. C.2, LACAVA, Z.G.M.3, AZEVEDO, R.B.3, FERREIRA, L.A.M.1,
OLIVEIRA, M.C1.
1
Faculdade de Farmácia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brasil.
Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto,
SP, Brasil.
3
Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, DF, Brasil.
[email protected]
2
Keywords: chloroaluminum phthalocyanine, liposomes, leishmaniasis.
1. Introduction
Cutaneous leishmaniasis (CL) is a parasitic
disease of the skin which is the result of
leishmanial infection of dermal macrophages.
So far, no treatment modality available has been
satisfactory. In this context, photodynamic
therapy (PDT) is an alternative therapy.
Photosensitizers molecules (PS) are irradiated
by light, generating reactive oxygen species that
induce reduction or destruction of the parasite.
Chloroaluminum phtalocyanine (ClAlPh) is a
kind of PS which have shown to be effective in
PDT of leishmaniasis. The use of drug delivery
systems can be a strategy to improve therapeutic
efficacy of ClAlPh. In this work, we
investigated the encapsulation of ClAlPh in
liposomes and their stability.
2. Methods
Liposomes
composed
by
egg
phosphatidylcholine were prepared by Bangham
method. After preparation, the vesicles were
submitted to extrusion in polycarbonates
membranes (0.4 µM) and purified by
ultracentrifugation. The liposomes were
prepared in concentrations of 2.9 (LIP 1) and
5.7 µg.mL-1 (LIP 2) of ClAlPh. These
formulations
were
characterized
by
encapsulated amount, diameter and zeta
potential. The storage stability of liposomes was
also performed at 15, 30 and 60 days after their
preparation. The evaluated parameters were
size, zeta potential and amount of encapsulated
ClAlPh.
3. Results
The liposomes containing 2.9 and 5.7 µg.mL-1
of ClAlPh presented an encapsulated amount
and zeta potential of 2.2 ± 0.06 µg.mL-1
and -18.4 ± 2.0 mV ; 4.1 ± 0.07 µg.mL-1 and
-16.2 ± 2.2 mV, respectively. The mean droplet
diameter was equal to 269 nm (LIP 1) and 264
nm (LIP 2). Both formulations were
monodisperse (polydispersity index < 0.2). All
evaluated parameters remained constant
(p>0.05) during a storage period of 60 days
indicating a good physico-chemical stability of
liposomes (Tables 1 and 2).
Table 1. Physico-chemical
liposomes containing ClAlPha
stability
of
Time 0
60 days
Zeta
Size
Zeta
potential
(nm)
potential
(mV)
(mv)
LIP 1
269±45b -18.4±2.0b 264±40b -17.6±2.5b
LIP 2
264±38b -16.2±2.2b 264±36b -16.9±0.5b
a
Each value represents the mean ± S.D (n=3); bThere is no
significant difference among the values indicated at the
same line (p>0.05).
Samples
Size
(nm)
Table 2. Chemical stability of liposomes
containing ClAlPha
Concentration of ClAlPh (µg.mL-1)
Time 0
15 days
30 days
60 days
LIP 1
2.2±0.06b
1.9±0.3b 2.1±0.36b 2.4±0.43b
LIP 2
4.1±0.07b
4.1±0.2b 3.7±0.51b 4.1±0.16b
a
Each value represents the mean ± S.D (n=3); bThere is no
significant difference among the values indicated at the
same line (p>0.05).
Samples
4. Conclusion
In this study, liposomes containing ClAlPh have
proved to be stable carriers. This formulation
can be a promising delivery system for
treatment of CL.
Acknowledgments
The authors would like to thank CNPq (INCT
Nanobiotecnologia) for financial support.