tailieunhanh - Drugs and Poisons in Humans - A Handbook of Practical Analysis (Part 48)

Introduction: Naphthalene (naphthalin) is being widely used as a moth repellant (insecticide), and being sold at supermarkets and general stores. Since one package of the compound usually contains as much as –5 g of naphthalene, the accidental ingestion of such a product by a small infant may cause fatality. However, recently, p-dichlorobenzene products, to be dealt with in the next chapter, have become more popular as a moth repellant. Naphthalene exists in the form of colorless crystals at room temperature, but easily sublimes into its gas with an aromatic odor exerting the repellant effect for insects. In this chapter, a. | Naphthalene by Kanako Watanabe Introduction Naphthalene naphthalin is being widely used as a moth repellant insecticide and being sold at supermarkets and general stores. Since one package of the compound usually contains as much as g of naphthalene the accidental ingestion of such a product by a small infant may cause fatality. However recently p-dichlorobenzene products to be dealt with in the next chapter have become more popular as a moth repellant. Naphthalene exists in the form of colorless crystals at room temperature but easily sublimes into its gas with an aromatic odor exerting the repellant effect for insects. In this chapter a method for headspace GC MS analysis of naphthalene is presented utilizing its volatile property. Reagent and their preparation i. Reagents Naphthalene can be purchased from Sigma St. Louis MO USA stable-isotopic naphthalene-d8a internal standard IS from Aldrich Milwaukee WI USA . Other common chemicals used are of the highest purity commercially available. ii. Preparation Naphthalene and naphthalene-d8 IS solutions 2-mg aliquot each is dissolved in 2 mL methanol to prepare stock solution separately. A 1-pL aliquot of each stock solution is injected into GC MS to measure each mass spectrum. For spiked tests the above each stock solution is diluted 10-fold with methanol a different volume of the naphthalene solution 1-10 pL containing pg and 10 pL containing 1 pg of naphthalene-d8 IS solution are placed in each glass vial with a Teflon-septum cap containing mL of blank whole blood. GC MS conditions GC column b an Rtx-1 fused silica medium-bore capillary column 30 m x mm i. d. film thickness pm Restek Bellefonte PA USA . GC conditions instrument a GC-17A gas chromatographc Shimadzu Corp. Kyoto Japan column oven temperature 50 C 1 min 10 C min 150 C 20 C min 280 C injection temperature 250 C carrier gas He its flow rate 3 mL min injection mode splitless for 1 min after injection followed by the .