Systems and methods for the identification of compounds in medical fluids using admittance spectroscopy

A benchtop drug solution analyzer for determining the identity, concentration or identity and concentration of a drug solution by admittance spectroscopy to determine surface interactions of the drug solution on fluid-contacting surfaces of a plurality of electrodes, the analyzer comprising:

• a measurement cell comprising a plurality of electrodes having fluid-contacting surfaces, the measurement cell configured to receive a sample of the drug solution so that the drug solution is contacted by the plurality of electrodes;
• a signal generator configured to provide electrical excitation at a plurality of frequencies for application from a plurality of pairs of electrodes of the measurement cell, wherein each pair of electrodes is configured to have different surface interactions with the solution at different frequencies than the other pairs of electrodes;
• a signal receiver configured to receive complex admittance data from the plurality of pairs of electrodes of the measurement cell;
• a controller configured to coordinate the application of signals from the signal generator, and the acquisition of complex admittance data from the signal receiver, to create an admittance spectrographic fingerprint of the drug solution, wherein the controller is configured to apply electrical excitation to each pair of electrodes that results in a voltage that is below 500 mV and below the threshold level for electrochemical reactions, further wherein the admittance spectrographic fingerprint comprises complex admittance information indicative of surface interactions between the drug solution and the fluid-contacting surfaces;
• and
• a processor configured to receive the admittance spectrographic fingerprint and to determine the identity, concentration or identity and concentration of one or more compounds in the drug solution by comparing the admittance spectrographic fingerprint to a library of admittance spectrographic data comprising complex admittance data measured from a plurality of known compounds and mixtures of compounds in a carrier solution at a plurality of frequencies and known concentrations.