ISSN:
1075-4261
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Physics
Notes:
Surface-enhanced resonance Raman scattering (SERRS) in silver colloids has been used to study the polyene antibiotic amphotericin B (AmB), its methylester (AmE), and its N-fructosyl derivative (N-Fru-AmB). The intensity of SERR spectra strongly varied with the amphotericin concentration, the nature of added salts, the Ag colloid preparation and the excitation wavelength. The systematic study of all these parameters allowed determination of optimal conditions for the specific detection of AmB and AmE. Under these conditions AmB was detected at 10-10 M in silver colloids prepared according to Creighton et al., with 60m M NaNO3, whereas in the case of AmE the detection threshold was 10-9 M in silver colloids prepared according to Lee and Meisel with 30m M NaCl. Circular dichroism (CD) was used as a complementary technique to study the self-association of the polyenes, characterized by a dichroic doublet at 340 nm. We observed that the addition of silver colloid leads to a modification in the structure of the self-associated species. © 1996 John Wiley & Sons, Inc.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
