Polymeric scaffolds for enhanced stability of melanin incorporated in liposomes

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:350

Article

Moraes, Marli L.¹  Gomes, Paulo J.²  Ribeiro, Paulo A.²  Vieira, Pedro²  Freitas, Adilson A.³  Koehler, Ralf⁴  Oliveira, Osvaldo N., Jr.⁵  Raposo, Maria² 

[1] Univ Fed Sao Carlos, BR-18043970 Sao Paulo, Brazil

[2] Univ Nova Lisboa, CEFITEC, Dept Fis, Fac Ciencias & Tecnol,FCT, P-2829516 Caparica, Portugal

[3] DEQB IST, Ctr Quim Estrutural, Lisbon, Portugal

[4] Helmholtz Zentrum Berlin Mat & Energie, D-14109 Berlin, Germany

[5] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13560970 Sao Paulo, Brazil

关键词: Melanin;    Liposome;    Dipalmitoyl phosphatidyl glycerol (DPPG);    Layer-by-layer films;    Fluorescence;    Neutron reflectivity;   

DOI  :  10.1016/j.jcis.2010.06.043

来源: Elsevier

【 摘 要 】

The use of melanin in bioinspired applications is mostly limited by its poor stability in solid films. This problem has been addressed here by incorporating melanin into dipalmitoyl phosphatidyl glycerol (DPPG) liposomes, which were then immobilized onto a solid substrate as an LbL film. Results from steady-state and time-resolved fluorescence indicated an increased stability for melanin incorporated into DPPG liposomes. If not protected by liposomes, melanin looses completely its fluorescence properties in LbL films. The thickness of the liposome-melanin layer obtained from neutron reflectivity data was 4.1 +/- 0.2 nm, consistent with the value estimated for the phospholipid bilayer of the liposomes, an evidence of the collapse of most liposomes. On the other hand, the final roughness indicated that some of the liposomes had their structure preserved. In summary, liposomes were proven excellent for encapsulation, thus providing a suitable environment, closer to the physiological conditions without using organic solvents or high pHs. (C) 2010 Elsevier Inc. All rights reserved.

【 授权许可】

Free