Programa de Excelência Acadêmica – Proex (PgPat/UFBA/FIOCRUZ), INCT-MCTI/CNPq/CAPES/FAPs N° 16/2014 and grants from the Fundação de Amparo à Pesquisa do Estado da Bahia – FAPESB and the Conselho Nacional de Pesquisa e Desenvolvimento Científico – CNPq. PSTV holds a grant from CNPq for productivity in research (307832/2015–5). In addition, this study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – Brasil (CAPES) – Finance Code 001. The authors also acknowledge support from the Serviço de Microscopia Eletrônica (SME) – FIOCRUZ/BA for TEM analysis and CIENAM/UFBA for size and zeta potential measurements17-N-allylamino-17-demethoxygeldanamycin (17-AAG, tanespimycin) is an inhibitor of heat shock protein 90 (Hsp90), which has been studied in the treatment of cancer such as leukemia or solid tumors. Alternatively, 17-AAG may represent a promising therapeutic agent against leishmaniasis. However, the delivery of 17-AAG is difficult due to its poor aqueous solubility. For exploring the therapeutic value of 17-AAG, we developed solid lipid nanoparticles (SLN) by double emulsion method. SLN exhibited ~100 nm, PDI < 0.2 and zeta potential ~20 mV. In addition, SLN were morphologically spherical with negligible aggregation. The entrapment efficiency of 17-AAG into the lipid matrix reached at nearly 80%. In a separate set of experiments, fluorescent SLN (FITC-labeled) showed a remarkable macrophage uptake, peaking within 2 h of incubation by confocal microscopy. Regarding the drug internalization as critical step for elimination of intracellular Leishmania, this finding demonstrates an important feature of the developed SLN. Collectively, these data indicate the feasibility of developing SLN as potential delivery systems for 17-AAG in leishmaniasis chemotherapy.