2.4.1. Vegetables (Parsley, Basil)
Two types of vegetables were chosen for analysis. These were
parsley and basil which were collected from the local supermarket.
Parsley and basil samples were air-dried followed by drying at
105 8C for 2 h and then powdered. 0.5 g of basil sample and 0.3 g of
parsley sample were taken in Teflon flasks, and 5.0 mL of
concentrated nitric acid and 5.0 mL of 30% (v/v) hydrofluoric acid
were added. After standing for 8 h, the samples were digested in a
microwave system for 10 min at 106 8C. The clear solutions
obtained were transferred to a 400 mL beaker; and diluted to
300 mL, then adjusted to the pH of 6.6.