Development of a Dispersive Liquid?Ionic Liquid Microextraction Method for the Determination of Nifurtimox and Benznidazole in Human Breast Milk. Optimization using a Central Composite Design.

PADRÓ, JM; PELLEGRINO VIDAL, R; AGUDELO MESA, LB; A CALIFANO; MARSON, M.; MASTRANTONIO, G; M. RETA

New Orleans

Simposio; 41st International Symposium on High Performance Liquid Phase Separations and Related Techniques; 2014

Iowa State University

Chagas disease, an infection caused by the protozoan parasite Trypanosomacruzi, constitutes a major public health problem in Latin America. The two drugscurrently available for the treatment, nifurtimox (NFX) and benznidazole (BNZ). Initialinfections with T. cruzi take place mostly in children, by vector or congenitaltransmission. As vector control improves, congenital transmission is rapidly becomingthe main route of infection, highlighting the importance of the diagnosis of maternalinfection. Human breast milk is a biological sample of great importance for theanalysis of therapeutic drugs, as unwanted exposure through breast milk could resultin pharmacological effects in the nursing infant. The goal of breast milk drug analysisis to inquire to which extent a neonate may be exposed to a drug during lactation.In this work, we developed a simple and efficient method to quantify BNZ andNFX in human breast milk, with a simple pre-treatment followed by a ionic liquidbased dispersive liquid?liquid microextraction (IL-DLLME), previous to an HPLC/UVanalysis. For the IL-DLLME technique, the ionic liquid (IL), [C8C1im][PF6], has beenused as ?extraction solvent? which was synthesized in our laboratory [1] andmethanol as ?disperser solvent?. According to a previous work [2], four significantvariables were selected to define the experimental field: volume of ionic liquid (VIL),volume of disperser solvent (VMeOH), KCl concentration (CKCl) and pH. A centralcomposite design (CCD) was used and mathematical models able to describe thesystem were obtained, thus allowing finding the optimal conditions for the analysis.The pH and VIL significantly affected the extraction response of BNZ, while for NFX,VIL, CKCl and the interaction term ?VIL x CKCl? were significant. At the optimumworking conditions, the predicted recoveries were 78.0 % and 91.6 % for BNZ andNFX, respectively. The reproducibility (inter-day) were 6.25 % and 5.77 % for BNZand NFX, respectively. Real samples were analysed and figures of merit wereobtained. The methodology is simple, robust, accurate and economical.