Photosensitized degradation of amoxicillin in natural organic matter isolate solutions

Title
Photosensitized degradation of amoxicillin in natural organic matter isolate solutions
Author(s)
정진영하오민 쑤[하오민 쑤]윌리엄 쿠퍼[윌리엄 쿠퍼]웨이후아 송[웨이후아 송]
Keywords
TREATMENT-PLANT EFFLUENT; BETA-LACTAM ANTIBIOTICS; SINGLET OXYGEN; AQUEOUS-SOLUTION; AQUATIC ENVIRONMENT; SURFACE WATERS; INDIRECT PHOTODEGRADATION; PHOTOCHEMICAL FORMATION; INDIRECT PHOTOLYSIS; ALGAL TOXICITY
Issue Date
201101
Publisher
PERGAMON-ELSEVIER SCIENCE LTD
Citation
WATER RESEARCH, v.45, no.2, pp.632 - 638
Abstract
Amoxicillin is a widely used antibiotic and has been detected in natural waters. Its environmental fate is in part determined by hydrolysis, and, direct and indirect photolysis. The hydrolysis rate in distilled water and water to which five different isolated of dissolved organic matter (DOM) was added, were evaluated. In the five different DOM solutions hydrolysis accounted for 5-18% loss of amoxicillin. Direct and indirect photolysis rates were determined using a solar simulator and it appeared that indirect photolysis was the dominant loss mechanism. Direct photolysis, in a solar simulator, accounted for 6-21% loss of amoxicillin in the simulated natural waters. The steady-state concentrations of singlet oxygen, (1)Delta O-2 (similar to 10(-13) M) and hydroxyl radical, center dot OH (similar to 10(-17) M) were obtained in aqueous solutions of five different dissolved organic matter samples using a solar simulator. The bimolecular reaction rate constant of (1)Delta O-2 with amoxicillin was measured in the different solutions, k(Delta O2) = 1.44 x 10(4) M-1 s(-1). The sunlight mediated amoxicillin loss rate with (1)Delta O-2 (similar to 10(-9) s(-1)), and with center dot OH (similar to 10(-7) s(-1)), were also determined for the different samples of DOM. While (1)Delta O-2 only accounted for 0.03-0.08% of the total loss rate, the hydroxyl radical contributed 10-22%. It appears that the direct reaction of singlet and triplet excited state DOM ((DOM)-D-3*) with amoxicillin accounts for 48-74% of the loss of amoxicillin. Furthermore, the pseudo first-order photodegradation rate showed a positive correlation with the sorption of amoxicillin to DOM, which further supported the assumption that excited state DOM* plays a key role in the photochemical transformation of amoxicillin in natural waters. This is the first study to report the relative contribution of all five processes to the fate of amoxicillin in aqueous solution. (c) 2010 Elsevier Ltd. All rights reserved.
URI
http://hdl.handle.net/YU.REPOSITORY/25726http://dx.doi.org/10.1016/j.watres.2010.08.024
ISSN
0043-1354
Appears in Collections:
공과대학 > 환경공학과 > Articles
Files in This Item:
There are no files associated with this item.
Export
RIS (EndNote)
XLS (Excel)
XML


qrcode

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

BROWSE