Detection of purine and pyrimidine nucleotides and underivatized nucleic acids by sinusoidal voltammetry

A device for detecting nucleotides and nucleic acid polymers in a sample comprising:

• an electrocatalytic metal electrode;
• means for bringing a sample into contact with the electrode;
• means for applying a sinusoidal voltage having an amplitude and a fundamental frequency to the electrode, the amplitude being sufficient to elicit a redox reaction of at least one form of nucleotides and nucleic acid polymers at the electrode;
• means for measuring a current at the electrode, the current resulting from the elicited redox reaction;
• means for producing a frequency spectrum of the measured current;
• and
• means for analyzing signal at of least one harmonic of the frequency spectrum greater than the fundamental frequency to detect nucleotides and nucleic acid polymers.

A method for detecting nucleotides and nucleic acid polymers in a sample comprising the steps of:

• contacting a surface of a copper electrode with the sample dissolved in an aqueous buffer with a pH of more than 7.0;
• applying a sinusoidal voltage having an amplitude of from about 0.05 V to about 0.55 V, measured against a silver/silver chloride electrode, and a fundamental frequency of 2 Hz. to the copper electrode to elicit a redox reaction of at least one form of nucleotides and nucleic acid polymers at the copper electrode;
• measuring a current at the copper electrode, the current resulting from the elicited redox reaction;
• producing a frequency spectrum of the measured current;
• and
• detecting the nucleotides and nucleic acid polymers by reference to a harmonic of the frequency spectrum greater than the fundamental frequency.

A device for detecting nucleotides and nucleic acid polymers in a sample comprising:

• a copper electrode;
• means for contacting the copper electrode with the sample dissolved in a high pH aqueous buffer;
• means for applying a sinusoidal voltage having an amplitude of from about 0.05 V to about 0.55 V, measured against a silver/silver chloride electrode, and a fundamental frequency of 2 Hz. to the copper electrode to elicit a redox reaction of nucleotides and nucleic acid polymers at the copper electrode;
• means for measuring a current at the copper electrode, the current resulting from the elicited redox reaction;
• means for producing a frequency spectrum of the measured current;
• and
• means for detecting the nucleotides and nucleic acid polymers by reference to a harmonic of the frequency spectrum greater than the fundamental frequency.