*2.2. Preparation of Chemicals*

To prepare NCC solution, 1 g of NCC was diluted in 100 mL deionized water. Then, 0.2 g of CTA was diluted in 20 mL of deionized water to obtain CTA solution. NCC solution was then dropped into CTA solution drop by drop while heat stirred for 24 h. The CTA-NCC solution was centrifuged at 3000 rpm for 15 min. Then, CTA-NCC/CGQD solution (0.05 wt%) was obtained by dispersing 1 mL of CGQD into 1 mL of CTA-NCC. The glucose solution was prepared by dissolving 9.91 mg of glucose with 100 mL of deionized water to produce 10 µM of glucose solution. To prepare glucose solution with various concentration, the 10 µM of glucose solution was diluted with deionized water based on the formula M1V<sup>1</sup> = M2V<sup>2</sup> to obtain 0.005, 0.01, 0.03, 0.05 and 0.1 µM of glucose [43–45].
