Separation of explosives from drinking water
|LiChroCART® 250-4 Purospher® RP-18 HC, 5 μm|
|Mobile phase||A: Acetonitrile / Methanol; 20 / 80, v/v
B: Sodium dihydrogenphosphate buffer (c = 0.01 mol/L, pH 4.5)
Gradient 0 min 35 % A; 28 min 55 % A; 40 min 85 % A; 50 min 85 % A; 51 min 35 % A; 71 min 35 % A
|Flow rate||0.8 mL/min|
|Detection||DAD 210 and 235 nm|
|In. volume||40 μL|
1. Octogen (HMX)
|Solid phase extraction with LiChrolut® EN (200 mg) (Cat. No. 1.19870):|
|Solvents||A: Methanol (LiChrosolv® Cat. No. 1.06007),
B: Acetonitrile (LiChrosolv® Cat. No. 1.00030);
C: Water (LiChrosolv® Cat. No. 1.15333).
|Sample pretreatment||Filtrate if necessary and add approx. 5 g NaCl / 1L water sample.
Conditioning of extraction column: 3 mL A, 3 mL B, 10 mL C, do not allow column to dry out!
|Sample application||pass 1 L water sample through the extraction column within 1 hour by using LiChrolut® extraction unit (Cat. No. 1.19851) which is connected to the water sample reservoir with PTFE hose (Cat. No. 1.22143) and a steel capillary.|
|Drying step||10 min by means of nitrogen and LiChrolut® drying unit (Cat. No. 1.19852).|
|Elution step||1 x 2 mL, then 1 x 3 mL A/B (1:1), collect in a conical flask and gently evaporate the solvent by means of nitrogen up to a and volume of 0.5 mL. Fill up to 1.0 mL with C. Subsequently filtrate sample into a 1.5 mL sample vial through a 0.2 μm membrane filter.|