Simultaneous electrochemical detection of gallic acid and uric acid with p-tert-butylcalix[4]arene-based coordination polymer/mesoporous carbon composite

Design and synthesis of an efficient electrocatalyst for simultaneous determination of gallic acid (GA) and uric acid (UA) is vital in the biological field. Herein, we synthesized a new p-tert-butylcalix[4]arene-based metal-organic electrocatalyst (Mn-L@MC) by combining Mn-L (H4L = tetrakis[(2-biphenylcarboxyl)oxy]-p-tertbutylcalix[4]arene) and mesoporous carbon (MC) via a simple mechanical grinding method. Synergistic effect between Mn-L and MC made the Mn-L@MC composite behave high-efficiency electrocatalytic performance toward simultaneous detection of GA and UA. Under optimal experimental conditions, the Mn-L@MC-2 electrode material featured relatively wide linear range (0.5-90 mu M) for the two analytes, and low determination limits of 0.043 mu M for GA and 0.059 mu M for UA. The remarkable electrochemical detection behavior of Mn-L@MC-2 electrode material toward GA and UA are comparable to those known sensors containing precious metals. The Mn-L@MC-2 material exhibited high selectivity, superior reproducibility, and acceptable stability during the determination of the two analytes. The sensor was assembled to simultaneously detect GA and UA in healthy human urine with satisfactory recoveries.

Automated summary

The design and synthesis of an efficient electrocatalyst for simultaneous determination of gallic acid (GA) and uric acid (UA) is crucial in the biological field. In this study, a new p-tert-butylcalix[4]arene-based metal-organic electrocatalyst (Mn-L@MC) was synthesized by combining Mn-L and mesoporous carbon (MC) using a simple mechanical grinding method. The synergistic effect between Mn-L and MC resulted in high-efficiency electrocatalytic performance of the Mn-L@MC composite towards simultaneous detection of GA and UA. The Mn-L@MC-2 electrode material exhibited a relatively wide linear range and low detection limits for the two analytes. The remarkable electrochemical detection behavior of Mn-L@MC-2 electrode material towards GA and UA is comparable to that of sensors containing precious metals. The material showed high selectivity, superior reproducibility, and acceptable stability during the determination of the two analytes.