Efficient detection of aflatoxins B1, B2, G1, and G2 has been performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using a UV-absorbing ionic liquid matrix to obtain "matrix-free" mass spectra and addition of NaCl to enhance sensitivity via Na+ cationization. Using ionic alpha-cyano-4-hydroxycinnamic acid (Et3N-alpha-CHCA) as the matrix, matrix-free mass spectra in the m/z range of interest are acquired, and the B1, B2, G1, and G2 aflatoxins are readily detected with an LOD as low as 50 fmol. The technique is fast, requires little sample preparation and no derivatization or chromatographic separation, and seems therefore to be suitable for high-throughput aflatoxin screening. It should be easily extended to other micotoxins and provide an attractive technique to control the quality of major crops subjected to huge world commercial trades such as peanuts, corn, and rice as well as to monitor bioterrorism threats by micotoxin poisoning.

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A fast procedure to classify perfumes and identify counterfeit samples is described. Dilution of a few microL of the sample in a 1:1 methanol/water solution is followed by detection of its major polar components via direct infusion electrospray ionization mass spectrometry (ESI-MS) in the positive ion mode. As proof-of-principle cases, three famous brands of perfumes were used. The ESI+-MS fingerprints of authentic samples were very characteristic, showing distinctive sets of polar markers for each sample. Principal component analysis (PCA) placed samples of the three perfume brands in well-defined groups. Counterfeit samples were also clearly detected owing to contrasting ESI-MS fingerprints, with PCA placing these samples far away from the authentic samples.

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