A method of synthesis of silver sols is introduced and characterized, which is easily made, reproducible and convenient
to combine with optical fiber. In a series of experiments, the hot spots in the mixture of silver sols just prepared and R6G
should be chosen to get the high signal-to-noise Raman spectra (RS) of analyte molecule. Surface-enhancement Raman
spectrums (SERS) of R6G are obtained in the form of thin film and liquid drop.