This program contains 3 projects following (i) the dopamine biosensor, (ii) the glucose sensor, and (iii) the uric sensor. The first project was the dopamine biosensors development using chitosan at carbon dots (CHIT@CD) and the tyrosinase enzymes (Tyr) deposit on the screen-printed carbon electrode (SPCE) (SPCE/CHIT@CD/Tyr). It showed 25 times usage, with a low detection limit of 0.036 ?M. This biosensor was successfully tested for dopamine in the blood sample provided with the percentage recovery in the range of 96.00 - 98.80 percent. The second project was the development of a glucose sensor on the glassy carbon electrode based on Ni particles and ordered mesoporous carbon. This glucose sensor showed a low detection limit at 0.59 ?M and it was successfully tested for glucose in urine samples with satisfactory percent recoveries. The last project was the development of a uric sensor based on Cu metal corporate with graphene oxide (GO) on a pencil carbon electrode (Cu@Go/PCE). This sensor was ability performed in the detection of uric in urine and blood sample. It was shown not significantly different at paired T-test to the standard method at 95% confidence level.