Fig. 6

Selectivity and practicality of the CSDR-Sensor. a Selectivity of the CSDR system with cocaine, benzoylecgonine (BE), and ecgonine methyl ester (EME). b Linear standard curves of cocaine detection in urine are obtained from 10 nM to 100 µM in an 8 cm distance in a capillary tube. Each data point is an average of three replicates (N = 3), and the error bars indicate the standard deviations