“…Ion-pair TLC with silica gel impregnated with Aliquat 336 in an Aliquat-saturated buffer (pH 7) with methanol was used for the separation of phenolic acids(100). The TLC of phenolic acids (and aldehydes) from the degradation of lignin was investigated on silica gel 60 F 254 impregnated with ferric chloride or nitrate(101) and re versed-phase separation of phenolic acids on silanized silica gel (sil C 18 -50 and RP-18) together with 4% detergent (either JV-dodecylpyridimum chloride or dodecylbenzenesulfonic acid)(102). The TLC separations of Copyright © 2003 by Taylor & Francis Group LLC…”