Determination of the Pesticide Napropamide in Soil, Pepper, and Tomato by Micelle-Stabilized Room-Temperature Phosphorescence

Abstract

A selective and sensitive method for determining napropamide by room-temperature phosphorescence in SDS micelles is proposed and applied to the determination of this substance in a technical formulation and in spiked soil, pepper, and tomato samples. The use of phosphorescence enhancers such as sodium dodecyl sulfate (micellar agent), thallium (I) nitrate (external heavy atom), and sodium sulfite (deoxygenation agent) was studied and optimized to obtain maximum sensitivity. The determination was performed in 66 mM SDS, 30 mM thallium (I) nitrate, and 8 mM sodium sulfite. Taking into account both maximum phosphorescence intensity and the time required to reach that, a pH value of 7.2 was selected. After the samples were left standing at room temperature for 10 min, the phosphorescence was totally developed. The intensity was then measured at lambda(ex) = 282 nm and lambda(em) = 528 nm. The calibration graph was linear for 50-600 ng mL(-1) napropamide. The detection limit, according to the error propagation theory, was 16 ng mL(-1). The method has been demonstrated for the analysis of soils, peppers, and tomatoes, but, because of matrix interference, the method of standard additions was applied to determine napropamide in the vegetable samples. Recoveries from all these matrixes of added napropamide were near 100%.

Luminescence methods for study and determination of pollutants in the environment

“…Since a large number of pesticides displayed relatively strong phosphorescence, several RTP methods have been applied to the environmental analysis of pesticides [99][100][101][102][103][104][105][106]. Segura et al [99] optimized a ME-RTP method in a dichloromethane/1-pentanol/SDS microemulsion to determine the insecticide carbaryl in real soil samples.…”

Persistence of Napropamide in/on Tea under North-East Indian Climatic Condition

“…1) is quite polar and slightly soluble in water and widely used as pre-emergence herbicide controlling in broad leaved weeds of tea, ground nut, citrus, grape vines, oil seeds, tobacco, tomatoes, and brinjal etc. (Agav and Voevodin 1985;Chang et al 1991;Kalinova and Rastenievdni 1991;Murillo Pulgariän and Garciäa Bermejo 2002). It is non-phytotoxic and gives full coverage of treated leaves but it is moderately toxic to fresh water fish (Anonymous 1984).…”

Applications of micelle enhancement in luminescence‐based analysis

“…These enhanced luminescence techniques have been developed for the detection of different categories of contaminants such as organic compounds, pesticides, metals and non‐metals. Table summarizes the enhancement effect of micelles in the luminescence detection of pollutants in water samples , canned beverages , soil , tomato and peppers , sewage , vegetables and fruits , potato pollutants and metals in aqueous samples over the last decade.…”