Automated Method for Extraction, Cleanup, and Gas Chromatographic Determination of Triazine Herbicides in Soil

Abstract

Complete automation of extraction, cleanup, and GLC determination of residue analysis of some important triazine herbicides in soils has been achieved. Manually sieved soil samples are continuously delivered to the system, which presents cleaned up extracts to an automated GLC injection system. Peak areas are calculated by a digital electronic integrator. The output of the integrator is connected to a teletype printer which generates both printed hard copy and a punched paper tape in standard ASCII code. This information is fed by a punchtape reader into a programmed Wang 700 desktop computer. Final analysis reports are printed by an attached typewriter. The system allows a 4-fold output of analytical results with half the personnel compared to manual analysis.

Comparison of extraction methods for triazine herbicides in root crops using electrolytic conductivity detection

“…The mixture was blended with 150 ml of methanol (225 ml for parsnips) (Delley et al, 1967;Shultz, 1970;Westlake et al, 1970). Other extracting solvents examined were: 80% (v/v) and 50% v/v methanol-water (Beynon, 1972); 90% (v/v) acetonitrile-water (Hormann et al, 1972); 35% (v/v) acetonitrile-water (Purkayastha and Cochrane, 1972); methanol-dichloromethane-ammonia (40:75:1) (Benfield and Chilweli, 1964); 65% v/v acetonitrile-water.…”

Atrazine, propachlor, and diazinon residues on small agricultural watersheds. Runoff losses, persistence, and movement

“…Extraction efficiencies for the soil samples were within the state-of-the-art for the technique used. Hormann et al (1972) reported extraction efficiencies of 70-80% for atrazine soil samples.…”

On-line liquid-liquid extraction in a segmented flow directly coupled to on-column injection into a gas chromatograph

“…A number of attempts toward the mechanization of sample workup procedures for chromatography have been made by utilizing flow techniques (6)(7)(8)(9)(10)(11)(12)(13). The earlier of these systems (8-11) made use of air segmented flow, incorporating the drawbacks inherent in this technique; low sample throughput, carryover, poor stability, and inefficient extraction (11,14,15).…”

“…The goal for the interface is to transfer the analyte, without losses or additions, from the workup unit to the analyzer. Most earlier systems were run separated from the gas chromatograph (8,(10)(11)(12)(13)18). The prepared samples were collected in vials and transferred to an autoinjector.…”