Evaluation of degradation of polyethylene glycol by ultra weak chemiluminescence and direct oxygen determination.

DOI NDL Digital Collections Web Site Web Site 1 Citations
  • IMAEDA Kazuo
    Department of Analytical Chemistry, Faculty of Pharmaceutical Science, Hoshi University
  • OHSAWA Keiko
    Department of Analytical Chemistry, Faculty of Pharmaceutical Science, Hoshi University
  • UCHIYAMA Katsumi
    Department of Analytical Chemistry, Faculty of Pharmaceutical Science, Hoshi University
  • MUTOH Akihiro
    Department of Analytical Chemistry, Faculty of Pharmaceutical Science, Hoshi University

Bibliographic Information

Other Title
  • 極微弱化学発光及び酸素直接定量法によるポリエチレングリコールの劣化度の評価
  • キョクビジャク カガク ハッコウ オヨビ サンソ チョクセツ テイリョウホウ

Search this article

Abstract

Ultra weak chemiluminescence occurs when a material is degraded. Degradation of macrogol 4000 was evaluated by measuring the ultra weak chemiluminescence. Intensity of ultra weak chemiluminescence from degraded macrogol 4000 by UV irradiation was compared with the oxygen content of the same material determined by direct oxygen determination method. An apparatus made for measuring ultra weak chemiluminescence consists of a photomultiplier tube R585 (Hamamatsu Photonics, Co., Ltd., Japan), a sample holder which is incorporated in a black box, a thermo-controller, and a photon counter C1230 (Hamamatsu Photonics, Co., Ltd., Japan). Macrogol 4000 was irradiated for 048 h by UV rays (maximum radiation band: 254 nm) at an intensity of 5μW/cm2. Intensity of ultra weak chemiluminescence reached a maximum after 3h of UV irradiations. Over 3h of UV irradiation, the intensity of chemiluminescence decreased. Oxygen content of macrogol 4000 showed the maximum (41.5%) at 5 h of UV irradiation. The value was about 4.8% higher than the theoretical oxygen content of macrogol 4000 (36.7%). The pH value of an aqueous solution of macrogol 4000 (1g/100 ml) the decreased according to UV irradiation time. The greatest decrease in the pH was observed at 57 h of UV irradiation. The IR spectra of macrogol 4000 (for 648 h of UV irradiation) showed a weak absorption band at about 1700 cm-1 corresponding to a carbonyl group. From these results it was suggested that the dissolved oxygen in the macrogol 4000 gave peroxyradical resulting in a high energy state aldehyde or ketone group for 03h of UV irradiation, so the intensity of ultra weak chemiluminescence increased. For 35h UV irradiation, macrogol 4000 incorporated atmospheric oxygen as the carbonyl group was oxidized to give carbonic acid or peroxy acid. After 5 h UV irradiation, the ether bonds of macrogol were cleaved to give volatile materials such as formaldehyde, formic acid, acetoaldehyde, and acetic acid. As these volatile acids or aldehydes vaporized in the air, oxygen content of macrogol decreased to the initial level. A combination of the measurement of ultra weak chemiluminescence and the direct oxygen determination would make a reliable and accurate evaluation method for degradation of materials.

Journal

  • BUNSEKI KAGAKU

    BUNSEKI KAGAKU 34 (9), 554-558, 1985

    The Japan Society for Analytical Chemistry

Citations (1)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top