Rapid screening of non-steroidal anti-inflammatory drugs illegally added in anti-rheumatic herbal supplements and herbal remedies by portable ion mobility spectrometry

In this work, for the first time, a high-performance ion mobility spectrometry with electrospray ionization (ESI-HPIMS) method has been employed as a rapid screening tool for the detection of acetaminophen, ibuprofen, naproxen, diclofenac sodium and indomethacin illegally added in anti-rheumatic herbal supplements and herbal remedies. Samples were dissolved and filtered through a 0.45 μm microporous membrane, then the filtrate was directly injected into the high-performance ion mobility spectrometry for analysis. Using this approach, the screening of illegal additions can be accomplished in as rapid as two to three minutes with no pretreatment required. The proposed method provided a LOD of 0.06-0.33 μg mL−1, as well as a good seperation of the five NSAIDs. The precision of the method was 0.1-0.4% (repeatability, n = 6) and 0.9-3.3% (reproducibility, n = 3). The proposed method appeared to be simple, rapid and highly specific, thus could be effective for the in-situ screening of NSAIDs in anti-rheumatic herbal supplements and herbal remedies.