Novel spectrofluorimetric method for boldine alkaloid determination in herbal drugs and phytopharmaceuticals

A new green on-line method for Boldine determination (BOL) in herbal drugs and phytopharmaceuticals, using its native fluorescence in acid media (λ_ex=282nm; λ_em=373nm) has been developed. The presented methodology involves for the first time, a flow injection (FI) strategy using a mini-column of multiwalled carbon nanotubes as retention agent coupled with molecular fluorescence. Different parameters influence as sample pH and flow rate, eluent flow rate and composition; on BOL sensitivity and elution time was investigated by multifactorial techniques. Adequate dynamic calibration range (r²=0.9993) was obtained over a concentration interval of 0.029-27.0μgmL^-1 BOL. The limits of detection (LOD) and quantification (LOQ) were 0.008 and 0.029μgmL^-1, respectively. The average recoveries in explored samples ranged from 95% to 103%. Under optimized conditions, the throughput sample as high as 30h^-1 was achieved with high repeatability performance (99%). The proposed development represents a useful and valuable tool emulating the analytical efficiency of the official methodologies for quality control of herbal and phytopharmaceutical drugs containing BOL. Moreover, this approach shows advantages respect to low cost, simplicity and environmental and analyst friendly.