Abstract: Collagen (50 mg) was dissolved in 6.5 mL acetic acid, the pH of the solution was adjusted to 4.7 with 5 M NaOH and diluted to 20 mL with water. Glass beads (2.5 ml), silanized and activated by the method of Tang et al., (Analyst, 1995, in press), were added together with 50 mg sodium cyanotetrahydroborate. The collagen-immobilized beads were washed with water and 0.5 M carbonate/bicarbonate buffer of pH 9.5 to produce a final volume of 4 mL. Lucifer Yellow VS (1.5 ml; 1 ml/ml in pH 9.5 buffer) was added and the mixture was inverted in the dark for 12 h. The dye-labelled collagen beads were washed with water and PBS containing 0.1%. Tween 20 and packed into a disposable plastic syringe tube which was incorporated into the flow injection system of Tang et al., (loc. cit.). Collagenase (20 µL; I) was injected into the flow system at 0.2 ml/min and the fluorescence emitted was measured at 540 nm (excitation at 430 nm). The calibration graph was linear up to 100 ng of I and the detection limit was 1.6 ng. The RSD (n = 7) was 3.5% at 10 ng of I.