Hitachi ZA3000 Series Instruction Manual page 511

4.2 Reagents
Note that the reducing agent should be prepared beforehand
because arsenic needs to be reduced in the four-liquid flow channel.
(1) 1% Sodium Borohydride (NaBH
Dissolve 5 g of sodium borohydride (analytical grade or higher)
and 2 g of sodium hydroxide (special grade or higher) with pure
water, and adjust the total volume to 500 mL.
(2) 1.0 mol/L Hydrochloric Acid (HCI)
Dilute 50 mL of hydrochloric acid (special grade or higher) by
adding 550 mL of pure water.
(3) Reducing Agent Solution
Dissolve 250 g of potassium iodide (special grade or higher) and
100 g of L(+)- ascorbic acid (special grade or higher) in pure
water and adjust the total volume to 500 mL.
(4) Standard Solutions
Dilute commercially available standard solution or arsenic
(approx. 1,000 mg/L).
NOTE 1: When using a toxic, corrosive, or stimulative reagent, be
careful not to incur a physical inflammation or injury.
Reagents should be properly treated by referring to SDS
(Safety Data Sheet) that provides information about
material characteristics and handling.
Wear proper protective clothes (e.g. safety goggles and
gloves) so that a reagent will not come into direct contact
with the skin.
Ventilate the laboratory room adequately to prevent
accidental inhalation of harmful vapor.
NOTE 2: Use the sodium borohydride solution only on the day it is
prepared. Do not keep the solution for a longer period
because hydrolysis reaction can occur during storage.
4 - 2
) Solution
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