A screening method based on 1D CSSF-TOCSY for the identification and quantification of 11 illegal adulterants in herbal medicines.

• Simultaneous identify and quantify 11 chemical adulterants in antitussive and antiasthmatic herbal medicinal products by an NMR analytical method. • Highly selective chemical shift filters with TOCSY allows acquiring specific background-free signals for each chemical adulterants to reduce the possibility of false-positives. • Fast and efficient sample preparation and analysis, and 1D CSSF-TOCSY method was well validated, satisfying all of the validation criteria, which has broad application prospects. In this work, an NMR analytical procedure based on highly chemical-shift-selective filtration (CSSF) with total correlation spectroscopy (TOCSY) was used for the rapid identification and quantification of trimethoprim, benproperine phosphate, diclofenac sodium, pentoxyverine citrate, diphenhydramine hydrochloride, sulfamethoxazole, dioxopromethazine hydrochloride, chlorphenamine maleate, prednisone acetate, theophylline, and diazepam in antitussive and antiasthmatic herbal medicinal products. This method is advantageous for content determination owing to its specific background-free signals for each chemical adulterant and easy-to-perform pretreatment operations. Satisfactory results in terms of limit of quantification (0.70–1.35 mg/g), precision (relative standard deviation, RSD%: 2.05–7.08), accuracy (bias%: 0.16–6.51), and recovery (85.4%–106.5%) were achieved. Among 28 batches of antitussive and antiasthmatic herbal medicinal products, 27 batches contained illegal adulterants, which differed in terms of the amount and type of compounds. The established method was employed for the qualitative screening and quantitative detection of illegal adulterants in herbal medicinal products because of its strong selectivity and fast analysis. Image, graphical abstract [ABSTRACT FROM AUTHOR]