A blood monitoring system is capable of monitoring the blood of a subject in vivo. The blood monitoring system comprises: 1) an array of movable microneedle micromachined within associated wells 2) array of motion actuators able to move each needle in and out of their associated wells 3) array of microvalves associated with each microneedle able to control the flow of air around the microneedle 4) an array of chemical sensors inserted into patient by movable microneedles 5) an array of inductors able to measure chemical concentration in the vicinity of inserted chemical sensors 6) conducting vias that provide timed actuating signal signals from a control system to each motion actuator 7) conducting vias that transmit signal produced by array of chemical sensors to the control system for processing, although the blood monitoring system can comprise other numbers and types of elements in other configurations.