STUDY ON THE SYNERGIC EFFECT OF CHITOSAN DEGRADATION IN HOMOGENEITY WITH HYDROPEROXIDE AND GAMMA CO-60 RADIATION
STUDY ON THE SYNERGIC EFFECT
OF CHITOSAN DEGRADATION IN HOMOGENEITY WITH HYDROPEROXIDE AND GAMMA CO-60
RADIATION
Bui Phuoc Phuc, Nguyen Trieu,
Ha Thuc Huy, Dang Van Phu1,
Nguyen Ngoc Duy1,
Nguyen Quoc Hien1
Faculty of Chemistry, University
of Natural Sciences
1Research
and Development Center for Radiation Technology, VAEC
Abstract
Beta-chitosan
with deacetylation degree (DD) 70.3% and mass average molecular weight (Mw0)
9.15 × 104 in dilute lactic acid solution was effectively degraded
by hydro peroxide (1%) under irradiation with gamma Co-60 radiation (1.33kGy/h)
in low dose range up to 16kGy. The degradation effect was studied by
measurement of Mw with gel permeation chromatography. Based on Mw
results, it indicated that the synergic effect of degradation was of 56% at
4kGy and gradually decreased to zero at 16kGy. Values of scission yield (Gs)
were found out to be Gsw = 22.51 × 10-7 mol/J and Gswo
= 2.83 × 10-7 mol/J for 5% chitosan (w/v) in solution with and
without 1% hydro peroxide, respectively. In addition, the structure of the
degraded product was characterized by Fourier transform infrared (FTIR)
spectroscopy. The DD value of chitosan calculated from FTIR spectra was almost
not changed by irradiation of chitosan solution either with or without 1% hydro
peroxide. The resultant oligochitosan products show highly elicitation effect
against diseases for plants (sugarcane and rice).
|
