Detection of GHRP-6 using a multi-walled carbon nanotube-based molecularly imprinted electrochemical sensor

Growth hormone-releasing hexapeptide (GHRP-6) is a kind of stimulant, which can be illegally used in athletic performance enhancement during sports. The accurate and sensitive detection of GHRP-6 is crucial for ensuring fair competition. Electrochemical sensors achieve quantitative analysis by monitoring the changes in electrochemical signals induced by target analytes. In this study, we developed an electrochemical sensor based on voltammetry to detect GHRP-6, providing a novel and advanced analytical methodology for its detection. The GHRP-6 was used as templates, phenol as polymer monomers, and MWCNTs as signal amplification materials, to build a detection method based on molecularly imprinted electrochemistry (MIEC). The fabricated sensor displayed rapid binding kinetics due to the location of all imprinting cavities on the polymer’s surface. This method displayed a linear relationship in the concentration range of 0.1 ∼ 100 ng/mL, featuring a detection limit of 1.21 pg/mL (S/N = 3). The percent recovery of GHRP-6 was 96.0 ∼ 103.2 % with the RSD in the range of 1.49 ∼ 5.56 %. The reproducibility test of the method resulted in an RSD of 3.19 %. Compared to the normal detection method, this technique shows more reproducibility and stability in real human serum samples. This study introduces an advanced, simple, and practical detection method for GHRP-6 in clinical samples.