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After intensely ultrasonic cracking, activated carbon obtained larger specific surface area in the premise of the high electric conductivity being maintained, which has provided a prerequisite for the construction of highly sensitive electrochemical sensors. An electrochemical sensor for sensitive analysis of puerarin in Radix Puerariae was successfully constructed using the prepared ultra-micro activated carbon in this work. The electrochemical behavior of puerarin on the sensor was investigated by cyclic voltammetry and differential pulse voltammetry. Moreover, the conditions of sensor preparing and puerarin detecting were optimized. Under the optimal conditions, the oxidation peak current increased linearly with the concentration of puerarin in the range of 2.4 x 10[?]7 mol L[?]1[?]1.54 x 10[?]5 mol L[?]1, and the detection limit was 6.4 x 10[?]8 mol L[?]1. In addition, the proposed sensor also exhibited good reproducibility, stability and selectivity. With superior performance in sample analysis, the proposed method would not only provide a new way for rapid and sensitive detection of puerarin, but also give a new idea for the application of activated carbon materials in the field of electrochemical sensors.

In this study, a newfangled molecularly imprinted electrochemical sensor based on nanoporous carbon (NC) was constructed and applied to the sensitive determination of calycosin in complex Chinese medicine samples. Aniline as functional monomer and calycosin as template were used to assemble molecularly imprinted polymer (MIP), which was bonded to the surface of NC modified glassy carbon electrode (GCE) by electropolymerization. After characterization of the successfully prepared MIP/NC composite, the electrochemical performance of the proposed sensor (MIP/NC/GCE) was evaluated by cyclic voltammetry, electrochemical impedance spectroscopy and chronocoulometry. The results proved that the sensor could accelerate electron transfer rate and heighten specific surface area. Under optimized conditions, the proposed sensor was used to detect calycosin, which displayed good reproducibility, stability and selectivity. The method demonstrated a liner range of 4.20 x 10[?]7[?]1.29 x 10[?]4 mol/L with the detection limit of 8.5 x 10[?]8 mol/L. Moreover, this study will provide a prospective exploration for the application of electrochemical analysis technology in the active ingredient detection of traditional Chinese medicine.

As hesperidin is a key indicator of some herbs and traditional Chinese medicine preparations, it is important to realize its sensitive, fast and high selective detection. In this work, prepared ultrafine activated carbon with high electrical conductivity was introduced as base decorated material of electrode, then with the use of self-assembly method and electro-polymerization method, the molecularly imprinted polymer was prepared on the electrode by using hesperidin as template molecular and o-aminothiophenol as functional monomer. Scanning electron microscope, cyclic voltammetry and electrochemical impedance spectroscopy were employed to characterize the morphological features and the stepwise modification of electrode, separately. The influence of pH, ratio of monomer to template, self-assembly time and so on were investigated and optimized. Under the optimized condition, the fabricated sensor exhibits a wide linear range from 85nM to 30uM with a low detection limit of 45nM. The decorated sensor has favorable selectivity, reproducibility and stability that could be used in real sample analysis.

After intensely ultrasonic cracking, activated carbon obtained larger specific surface area in the premise of the high electric conductivity being maintained, which has provided a prerequisite for the construction of highly sensitive electrochemical sensors. An electrochemical sensor for sensitive analysis of puerarin in Radix Puerariaewas successfully constructed using the prepared ultra-micro activated carbon in this work. The electrochemical behavior of puerarin on the sensor was investigated by cyclic voltammetry and differential pulse voltammetry. Moreover, the conditions of sensor preparing and puerarin detecting were optimized. Under the optimal conditions, the oxidation peak current increased linearly with the concentration of puerarin in the range of 2.4 × 10−7mol L−1∼1.54 × 10−5mol L−1, and the detection limit was 6.4 × 10−8mol L−1. In addition, the proposed sensor also exhibited good reproducibility, stability and selectivity. With superior performance in sample analysis, the proposed method would not only provide a new way for rapid and sensitive detection of puerarin, but also give a new idea for the application of activated carbon materials in the field of electrochemical sensors.

As hesperidin is a key indicator of some herbs and traditional Chinese medicine preparations, it is important to realize its sensitive, fast and high selective detection. In this work, prepared ultrafine activated carbon with high electrical conductivity was introduced as base decorated material of electrode, then with the use of self-assembly method and electro-polymerization method, the molecularly imprinted polymer was prepared on the electrode by using hesperidin as template molecular and o-aminothiophenol as functional monomer. Scanning electron microscope, cyclic voltammetry and electrochemical impedance spectroscopy were employed to characterize the morphological features and the stepwise modification of electrode, separately. The influence of pH, ratio of monomer to template, self-assembly time and so on were investigated and optimized. Under the optimized condition, the fabricated sensor exhibits a wide linear range from 85nM to 30μM with a low detection limit of 45nM. The decorated sensor has favorable selectivity, reproducibility and stability that could be used in real sample analysis.

In this study, a newfangled molecularly imprinted electrochemical sensor based on nanoporous carbon (NC) was constructed and applied to the sensitive determination of calycosin in complex Chinese medicine samples. Aniline as functional monomer and calycosin as template were used to assemble molecularly imprinted polymer (MIP), which was bonded to the surface of NC modified glassy carbon electrode (GCE) by electropolymerization. After characterization of the successfully prepared MIP/NC composite, the electrochemical performance of the proposed sensor (MIP/NC/GCE) was evaluated by cyclic voltammetry, electrochemical impedance spectroscopy and chronocoulometry. The results proved that the sensor could accelerate electron transfer rate and heighten specific surface area. Under optimized conditions, the proposed sensor was used to detect calycosin, which displayed good reproducibility, stability and selectivity. The method demonstrated a liner range of 4.20 × 10−7∼1.29 × 10−4mol/L with the detection limit of 8.5 × 10−8mol/L. Moreover, this study will provide a prospective exploration for the application of electrochemical analysis technology in the active ingredient detection of traditional Chinese medicine.