RESEARCH ARTICLE Copyright © 2012 American Scientific Publishers All rights reserved Printed in the United States of America Journal of Nanoscience and Nanotechnology Vol. 12, 1–5, 2012 New Magnetic Fluid Developed with Natural Organic Compounds Biocompatible J. G. Santos 1 ∗ , L. B. Silveira 1 , P. H. S. Fegueredo 1 , B. F. Araújo 1 , W. S. Peternele 1 , A. F. R. Rodriguez 2 , E. C. Vilela 4 , V. K. Garg 3 , A. C. Oliveira 3 , R. B. Azevedo 5 , and P. C. Morais 3 1 Laboratório de Nanomateriais e Nanobiomagnetismo-LNBIOMAG, Universidade Federal de Rondônia, Porto velho, RO 76900-900, Brazil 2 Departamento de Ciências, Universidade Federal do Acre, AC 79900-000, Brazil 3 Instituto de Física, Universidade de Brasília, Núcleo de Física Aplicada, Brasília, DF 70910900, Brazil 4 Instituto de Química, Central Analítica, Campus Samambaia – UFG-GO, Brazil 5 Universidade de Brasília, Instituto de Biologia, 70919-970, Brasília - DF, Brazil This work was developed with an aqueous suspension of maghemite nanoparticles and colloidal emulsions with nanoparticles of magnetite. The nanoparticles were synthesized by co-precipitation method. The first was the magnetic emulsion nanoparticles of maghemite dispersed in the aque- ous extract obtained from the leaf embauba (Cecropia Obtusifolia), whose tree is native to Central and South America. Thereby achieving the magnetic fluid extract embauba stabilized with ionic buffer solution pH 7.4. A second emulsion was prepared with colloidal magnetite nanoparticles with surfaces previously coated with oleic acid as a means of dispersing and using the oil extracted from in nature seed Andiroba (Carapa Guianensis), tree of the Brazilian Amazon. These new mag- netic fluids the nanoparticles were characterized by Photoacoustic spectroscopy (PAS) to deter- mine the coating layer of molecules on the surfaces of nanoparticles. In aqueous ionic magnetic fluid Cecropia Obtusifolia (MFCO) chlorogenic acid contributes to the electron density in the pres- ence of four groups alcohols, a ketone group and a carboxylic group. In magnetic fluid-based oil andiroba MFAD PAS spectra show that oleic acid molecules are tightly linked on the surface of the nanoparticles. Keywords: Cecropia Obtusifolia, Andiroba Oil, Maghemite, Magnetite, Nanoparticles, Magnetic Colloidal Emulsion, Embauba, Carapa Guianensis, Andiroba. 1. INTRODUCTION Biocompatible magnetic fluid have attracted intense inter- est in recent years, particularly due to the positive impact they offered to the biological and biomedical applications, ranging from the cell sorting technology to alternative can- cer therapies. 1 2 More recently, huge effort has been done towards the design and synthesis of new drug delivery sys- tems using biocompatible magnetic fluid. 3 4 Preparation of magnetic fluids using plant extracts and essentials oil used in folk medicine is an innovative alternative. A biomedical application of magnetic fluid requires that the material has chemical stability and no trace of toxicity. Requires that the size of the nanoparticles have a uniform distribution between 3–10 nm. 5 In addition to the magnetic nanoparticle the hosting template may carry a specific drug as well. ∗ Author to whom correspondence should be addressed. As long as the end news magnetic fluid based in natural layer offers long term biocompatibility and chemical sta- bility a wide range of applications opens up based on such material platform. 4–8 Cecropia Obtusifolia (Cecropiaceae) (see Fig. 1(a)) as embauba (Brazil) is a species from tropical America and its leaves are used in traditional medicine for the treatment of diabetes, an anti-inflammatory, hypoglycemic, hypolipi- demic agent and antioxidant proprieties. 9 Contain phenolic bioactive compounds such as chlorogenic acid, flavonoids and isoorientin. The extracts were monitored by HPLC for the chemical constituents and lyophilized. In the present study, concentred aqueous extract Cecropia Obtusifolia (COAE) were used as the biocompatible template to host different concentrations of maghemite nanoparticles sam- ples forming a magnetic colloidal suspension a new mag- netic fluid Cecropia Obtusifolia (MFCO). J. Nanosci. Nanotechnol. 2012, Vol. 12, No. xx 1533-4880/2012/12/001/005 doi:10.1166/jnn.2012.4917 1