Stock borate saline buffer (Kotoulas and Moroz' 1971) containing 0O15 M sodium chloride and O-15 M boric acid was adjusted to pH 8 6 with sodium hydroxide and used as a 10% solution. Stock potassium phosphate buffer pH 7, 1 mol/l containing sodium azide (2 g/l) was diluted to 0-1 mol/l for use and Tween 20 (0 05%) was added to reduce nonspecific binding effects (Engvall and Perlmann, 1972). A stock solution (10 mg/ml) of rabbit FIl in phosphate buffer was prepared and filtered for use. It was stored at -20°C. Alkaline sodium dodecyl sulphate (SDS) was prepared using 2 g/100 ml 0 -1 N NaOH.
MethodUsing a 1 cm diameter quartz cell in a Locarte digital fluorimeter with 13 stage PM tube and zinc lamp, the optimum sensitivity was achieved with a primary filter combination 805 Q (Ilford) and BG 12/2 mm (Schott) and secondary filters 805 Q, OG 515/2 mm, and Wratten 55 (Kodak). The instrument response was linear, turbidity interference minimal, and stability within experiments and between days high after a few minutes' warm-up. After treatment with ethanol and hot 40 % caustic soda solution, the plastic discs were rinsed 247 on 6 April 2019 by guest. Protected by copyright.