A preliminary study of light-ageing effects on the analysis of natural flavonoid-dyed wools by photodiode array HPLC and by direct temperature mass spectrometry

Initial results from high performance liquid chromatographic (HPLC) analysis of accelerated fluorescent tube- and mercury-incandescent lamp-aged mordanted wools dyed with old fustic, weld, quercitron bark, quercetin, dyer's greenweed and onion skins indicate that additional chromophoric and non-chromophoric compounds are generated upon photodegradation.Greater amounts of these components were generated after mercury-incandescent light-ageing with respect to ultraviolet-filtered fluorescent light-ageing. Total amounts recovered from dyed wools of quercetin (onion skins); luteolin and apigenin (both weld and dyer's greenweed); and genistein (dyer's greenweed) all increased upon accelerated ageing. While several hypotheses are offered, further experimentation may explain this interesting phenomenon. Direct temperature mass spectrometry (MS) was successfully applied as a novel and promising technique for in situ dyed fibre analysis. Preliminary results for some of the light-aged wools above demonstrated its potential for studying changes dye-fibre interaction upon ageing.