MATRIX: Soy flour
ANALYTES: Alachlor and atrazine
RANGE OF DETECTION: Alachlor: 20 to 1000 ppb, Atrazine: 14 to 400 ppb.
Alachlor RaPID AssayÒ kit and Sample Diluent. HS Atrazine RaPID AssayÒ kit and Sample Diluent. Reagents: methanol (pesticide grade); concentrated hydrochloric acid (ACS grade); distilled or deionized water Equipment: homogenizer, or laboratory blender with 150 mL capacity (minimum) sample containers; 500 mL graduated cylinder; 250 mL capacity beaker or flask; 50 mL polypropylene conical tubes; pipet calibrated to dispense 50 mL (atrazine) or 100 mL (alachlor); 13 x 100 mm glass test tubes, serological pipets, vortex mixer, scale or balance.
Use appropriate safety precautions when handling concentrated acid. Prepare 0.1 N HCl: Measure 238 mL distilled or deionized water into a beaker or flask. Slowly add, while mixing, 2.0 mL concentrated hydrochloric acid. Prepare extractant: Measure 400 mL methanol into 500 mL graduated cylinder. Add 0.1 N HCl to a final volume of 500 mL. Mix well. Allow solution to cool to room temperature.
Homogenizer: Add 20 mL of extractant to 5 grams of soy flour in a 50 mL conical tube. Homogenize for 15 seconds on high speed. Allow solids to settle for 10 minutes (or centrifuge). Blender: Add 80 mL of extractant to 20 grams of soy flour in the blender container. Blend for 2 minutes on high speed. Transfer the homogenate to a 50 mL conical tube. Allow the solids to settle for 10 minutes (or centrifuge).
Alachlor: Transfer 100 mL of the extract to exactly 4.9 mL of the Alachlor Sample. Diluent in a glass tube. Vortex to mix.
Atrazine: Transfer 50 mL of the extract to exactly 4.95 mL of the HS Atrazine Sample. Diluent in a glass tube. Vortex to mix.
Analyze the diluted extract as the 'sample' according to package insert of the RaPID Assay.