A cost-effective and sensitive voltammetric sensor for determination of baicalein in herbal medicine based on shuttle-shape α-Fe2O3 nanoparticle decorated multi-walled carbon nanotubes

Excessive intake of baicalein (BA) may lead to many adverse heathy risks. Hence, it is highly desirable to develop a convenient and sensitive method for the determination of BA. Herein, a low-cost and highly sensitive electrochemical sensor was fabricated for determination of BA in herbal medicine based on shuttle-shape α-Fe 2 O 3 nanoparticles decorated multiwalled carbon nanotubes (s-Fe 2 O 3 /MWCNTs). Various microscopic and spectroscopic methods confirmed the successful formation of s-Fe 2 O 3 /MWCNTs. CV and EIS techniques revealed that the s-Fe 2 O 3 /MWCNTs significantly improved the electroactive surface area and electron transport ability. Owing to the synergistic interactions between s-Fe 2 O 3 NPs and MWCNTs, the s-Fe 2 O 3 /MWCNTs exhibited superior electrocatalytic toward BA oxidation through a two electrons two protons pathway. Under optimal experimental conditions (accumulation potential of 0 V, accumulation time of 120 s, and pH of 6.0), The s-Fe 2 O 3 /MWCNT/GCE displayed a wide detection range from 0.001 to 10 μM with an ultrahigh sensitivity (6.154 μA μM −1 ) and extremely low limit of detection (0.2 nM). The s-Fe 2 O 3 /MWCNTs demonstrated strong anti-interfering ability against common potential interfering substances even at high concentration, and maintained stable peak current responses for at least 2 weeks. Furthermore, the s-Fe 2 O 3 /MWCNTs achieved the reliable detection of BA in traditional herbal medicine with satisfactory recovery (97 − 105 %). Considering their low cost, convenient operation, and comprehensive sensing performance, the s-Fe 2 O 3 /MWCNTs have demonstrated promising application prospects in sensitive detection of flavonoids.