2.2. Needle-type enzyme sensor and measurement
Fig. 1 shows a schematic of the needle-type enzyme sensor
and images of the detector region. The sensor consists
of a needle-type hollow container, immobilized enzyme membrane
and optic fiber probe with ruthenium complex. The sensor
assembly is described below.
2.2.1. Needle-type hollow container
The hole at the tip of a commercially available 18-gauge
needle (diameter: 1.2 mm; Terumo, Tokyo, Japan) was blocked
using epoxy resin (Toagosei Co., Tokyo, Japan). Next, 4×
1.0mm holes were made on one side of the needle, and 4×
0.8mm holes were made on the opposite side (Fig. 1A and E).