Determination of ephedrine in herbal mixtures using the optimized sensor and the recovery of spiked standard concentrations.

Herbal product	EPH concentration in the sample (ppm ± % RSD)a	Spiked EPH standard (recovery% ± % RSD)a
Royal Regime Tea®	Nil	105.03 ± 2.41
Herbal mixture of unknown composition purchased from a local apothecary	227.01 ± 3.418	98.85 ± 4.81

^aAverage of five determination.