Measurements of insulin quantities in a syringe are performed capacitively in an integrated insulin dose recorder/blood glucose meter. The syringe is placed in a holder before and after the administration of the dose. Capacitor electrodes may be situated within the syringe and/or outside the syringe...http://www.google.co.uk/patents/US6110148?utm_source=gb-gplus-sharePatent US6110148 - Capacitance-based dose measurements in syringes
