MATRIX: Wood, reduced to fine shavings or sawdust
ANALYTE: Pentachlorophenol (PCP)
RANGE OF DETECTION: 1 to 100 ppm
Pentachlorophenol RaPID AssayÒ Kit and Sample Diluent Reagents: acetonitrile (pesticide grade). Equipment: reciprocating shaker, plastic bottles (polypropylene or high density polyethylene, 30 mL) with plastic lined caps, 13 X 100 mm glass test tubes, serological pipets, vortex mixer, scale or balance, and equipment/tools for reducing wood to fine particles (refer to sample treatment section below).
If necessary, reduce wood poles, boards or lumber to fine chips, shavings or sawdust. Boring holes into the wood with a drill bit will generate shavings or chips that can be further reduced to fine particles using a coffee grinder or mill (e.g. Electric Seed & Coffee Mill, Model MC-170, Markson Science, Inc., Phoenix, AZ). Finer particulates will increase the pentachlorophenol extraction efficiency of this procedure. Do not perform the extraction procedure on moist wood. Air dry moist samples by spreading chips, shavings or sawdust in a thin layer for up to 24 hours at room temperatures.
Add 20 mL of acetonitrile to 1 g of reduced wood sample in a 30-mL plastic bottle. Position the sample bottle on its side and shake vigorously on reciprocating shaker at medium speed (100 cycles/min.) for 24 hours. This extraction will result in an extraction efficiency of approximately 70%. Longer extraction times can be used to increase extraction efficiency (refer to Procedural Notes section). Allow wood particles to settle for approximately 5 minutes.
Dilute the extract 500x (fold) with Sample Diluent. This can be prepared by making serial dilutions. Prepare the first dilution (25x) by transferring 0.20 mL of the extract to 4.80 mL of Sample Diluent. Mix thoroughly. Then transfer 0.25 mL of the first dilution to 4.75 mL of Sample Diluent. Mix thoroughly. Analyze the final dilution as the 'sample' according to package insert of the RaPID Assay.