Described herein is an amperometric biosensor, e.g., chronoamperometric biosensor for the measurement of the concentration of nicotine. Also disclosed herein is a wearable nicotine biosensor device and a biosensor that detects nicotine in smoke. The biosensor disclosed herein comprises a nicotine-catalyzing enzyme, such as NicA2 or mutant NicA2 enzymes. Also described herein are systems comprising said amperometric biosensor, e.g., chronoamperometric biosensor and methods of using said chronoamperometric biosensor.

A method of measuring and identifying LSD and its major metabolite O-H-LSD, by obtaining a sample from an individual, and measuring, identifying, and quantifying LSD and O-H-LSD in the sample by performing a LC-MS/MS analysis. A method of treating and monitoring individuals taking LSD, by administering a microdose of LSD, a prodrug of LSD, or an analog of LSD to the individual, monitoring the individual by obtaining a sample from an individual and measuring and identifying the analytes in the sample by performing a LC-MS/MS analysis, and adjusting the microdose based on the amount of LSD quantified in the LC-MS/MS analysis. A method of adjusting dosing of LSD, by administering a microdose of LSD, a prodrug of LSD, or an analog of LSD to the individual, and adjusting the microdose based on blood concentration analytics.

Assays and methods for verifying the validity of a urine sample submitted for Drugs of Abuse (DOA) testing. Embodiments include a SUD Diagnostic Panel that includes six assays: specific gravity index assay, long-duration counterfeit urine assay, short-duration counterfeit urine assay, oxidant history assay, pH assay, and creatinine assay. The SUD Diagnostic Panel detects twelve principle classes of adulteration. Detection of adulteration of one or more urine samples from a patient indicates an attempt to subvert test results and provides an objective indication in one instance and an object diagnosis in another instance of SUD.

Provided is a coronavirus detection method which is suitable for a coronavirus disease 2019 (COVID-19) detection. The method includes the following steps. A field-effect transistor-based biosensor (BioFET) platform is provided, wherein the BioFET platform includes a BioFET and a sensor card. The sensor card is detachably connected to the BioFET, wherein the sensor card includes a plurality of sensors and each of the plurality of sensors includes a response electrode. A nucleic acid probe specific to a nucleic acid sequence of COVID-19 virus is immobilized on a surface of the response electrode. A test solution is placed on the response electrode of the sensor card. A pulse voltage is applied to the response electrode, and a detection current generated from the sensor card is measured.

The method uses a device which measures the volatile organic compounds (VOCs) present in headspaces of fluid samples to differentiate between authentic and synthetic urine samples. The method includes the use of a device which includes an array of resistive microchemical sensors. The device may be exposed to samples of synthetic and authentic urine to identify a pattern of VOCs in each, these steps being referred to herein as training the device. The device may then be exposed to a urine sample of unknown authenticity and a pattern of VOCs identified. The pattern of VOCs from the urine sample of unknown authenticity may be compared to those of synthetic and authentic urine. In some embodiments the device is installed in a toilet. The method may be used to identify a false sample provided for a urine analysis intended to screen for use of illicit drugs.

The embodiments disclose a method including functionalizing a biosensor with a biologic analytical target prior to installation into a detection cartridge, depositing a test subject bodily fluid test sample onto the biosensor surface, inserting the detection cartridge into a portable detection cartridge reader, measuring the electrical impedance of the bodily fluid test sample across biosensor energized electrodes, providing algorithms for analyzing measured electrical impedance data of the bodily fluid test sample obtained in the detection cartridge, identifying and determining the presence of biologic analytical target molecules in the bodily fluid test sample, and transmitting results of the test results to the test subject.

A system for diagnosing COVID-19 infection. The system includes a biosensor, an electrochemical stimulator-analyzer, and a processing unit. The biosensor is configured to be put in contact with a blood serum sample of a person suspected to be infected of COVID-19 virus. The processing unit is configured to apply an AC potential amplitude to the biosensor while sweeping a frequency range utilizing the electrochemical stimulator-analyzer, recording an electrochemical impedance spectroscopy (EIS) associated with the blood serum sample utilizing the electrochemical stimulator-analyzer, calculating a charge transfer resistance (R.sub.CT) of the recorded EIS, and detecting a COVID-19 infection of the person based on the calculated R.sub.CT if the calculated R.sub.CT is equal to or more than a threshold value.

The embodiments disclose a method including functionalizing a biosensor with a biologic analytical target prior to installation into a detection cartridge, depositing a test subject bodily fluid test sample onto the biosensor surface, inserting the detection cartridge into a portable detection cartridge reader, measuring the electrical impedance of the bodily fluid test sample across biosensor energized electrodes, providing algorithms for analyzing measured electrical impedance data of the bodily fluid test sample obtained in the detection cartridge, identifying and determining the presence of biologic analytical target molecules in the bodily fluid test sample, and transmitting results of the test results to the test subject.

Systems and methods of functionalizing a graphene sensor surface are provided. A representative method of functionalizing the graphene sensor surface includes providing a graphene layer including a sensor surface. The method may include binding a plurality of molecular complexes to the sensor surface of the graphene layer using a buffer solution. Each molecular complex may include a linker molecule configured to couple to the sensor surface at a first linker position, and a binding molecule coupled to the linker molecule at a second linker position different from the first linker position. The representative method further includes coupling one or more detector molecules to a first subset of the molecular complexes and coupling one or more passivation agents to a second subset of the molecular complexes. At least some of the molecular complexes of the first subset are different from those of the second subset.

Systems and methods for oxidizing phenolic cannabinoids with fuel cells are described. The oxidation processes for phenolic cannabinoids and/or Δ.sup.9-THC can be detected and the concentration of phenolic cannabinoids and/or Δ.sup.9-THC can be reported directly with fuel cells. Many embodiments provide integrating cannabinoid fuel cells into marijuana breathalyzer devices.