Cheng Ching K. Chiang1, Balaka Barkakaty2, Judit E. Puskas1,3, Wenshuang Xie4, Katrina Cornish4, Federic Peruch5, Alain Deffieux5
This paper reports the investigation of the compn. of guayule latex and washed rubber particles (WRPs) using high-resoln. size exclusion chromatog. (SEC) and matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI-ToF MS). Guayule WRPs and inactive homogenate were analyzed by high-resoln. SEC. Guayule WRPs extd. from different batches showed that the concn. of low MW fractions in the WRPs were lower (27-31 %) than in the inactive homogenate (54%). The low MW region in the WRPs showed only three (L2, L4, and L5 in WRP 02_28_11) or four peaks (in WRP 11_17_11 and WRP 02_23_11), with MWs between 400 and 8000 Da. ALDI anal. of the SEC-fractionated low MW fractions verified oligoisoprene structures, with a mass difference of 68 Da (mass of one isoprene unit) between the major peaks.