Tropical peat as a versatile material for solid-phase extraction of pesticides from medicinal plant Cordia salicifolia

Abstract

A turfa natural foi testada na extração em fase sólida de acefato, clorprofam, pirimicarbe, bifentrina, tetradifona e fosalona da planta medicinal Cordia salicifolia, utilizando cromatografia a gás acoplada a espectrometria de massas no modo de monitoramento de íons selecionados. Considerando que a legislação brasileira não estabelece limites máximos de resíduos para plantas medicinais, a recuperação foi avaliada em dois níveis de concentração (0,5 e 1,0 mg kg -1 ), resultando em valores de recuperação entre 64% e 118%, com coeficientes de variação entre 5,6% e 26,4% para a turfa. Os limites de detecção variaram entre 0,10 e 0,15 mg kg -1 , enquanto que os limites de quantificação, entre 0,15 e 0,25 mg kg -1 para os pesticidas estudados. O método desenvolvido foi linear no intervalo de 0,1 a 5,0 µg g -1 , com coeficientes de correlação entre 0,9975 e 0,9986. A comparação entre a turfa natural e o sorbente convencional (alumina neutra) apresentou desempenho similar da turfa na recuperação dos seis pesticidas.Natural peat was tested for solid-phase extraction of acephate, chlorpropham, pirimicarb, bifenthrin, tetradifon and phosalone from the medicinal plant Cordia salicifolia, using gas chromatography-mass spectrometry with selected ion monitoring (GC/MS, SIM). Considering that there are no Brazilian regulations concerning maximum permissible pesticide residue concentrations in medicinal herbs, recovery experiments were carried out (three replicates) at two arbitrary fortification levels (0.5 and 1.0 mg kg -1 ), resulting in recoveries ranging from 64% to 118% and relative standard deviations between 5.6% and 26.4% for peat sorbent. Detection and quantification limits for herb ranged from 0.10 to 0.15 mg kg -1 and from 0.15 to 0.25 mg kg -1 , respectively, for the different pesticides studied. The developed method was linear over the range assayed, 0.1-5.0 µg g -1 , with correlation coefficients ranging from 0.9975 to 0.9986 for all pesticides. Comparison between natural peat and conventional sorbent (neutral alumina) showed similar performance of peat for the six pesticides tested.Keywords: peat, pesticides, medicinal herb, matrix solid phase dispersion, gas chromatographymass spectrometry IntroductionMedicinal plants are consumed worldwide for treatment of disease and are important raw material for pharmaceutical industry production for phytopharmaceuticals. The significant increase in the use of medicinal herbs in recent decades may be attributed to popular knowledge, the cost of synthetic drugs and the resurgence of interest in the development of new drugs. World Health Organization report indicated that about 70-80% of the world population rely on non-conventional medicines mainly of herbal sources in their primary health care. 1 Traditionally herbs and herbal products have been considered to be gentle, nontoxic and even harmless mainly because of their "natural" origin. 1-3 Cordia salicifolia Cham (Boraginaceae family syn. Cordia ecalyculata Vell.) also known by several common names such as "porangaba", "ch...

Fractal aggregation and disaggregation of newly formed iron(iii) (hydr)oxide nanoparticles in the presence of natural organic matter and arsenic

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Pesticide Residues in Natural Products with Pharmaceutical Use: Occurrence, Analytical Advances and Perspectives

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Fluoranthene Biodegradation by Serratia sp. AC-11 Immobilized into Chitosan Beads

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