SCANNING NEAR-FIELD FLUORESCENCE MICROSCOPY OF A PHASE-SEPARATED HYDROCARBON-FLUOROCARBON MIXED MONOLAYER

We previously developed scanning near-field fluorescence microscopy (S NFM) by combining SNOM and atomic force microscopy (AFM). We demonstra te that this combination can be used for fluorescence imaging and spec troscopy for a localized nanoarea. A small amount of a cationic cyanin e dye with two long alkyl chains (CD) was added to see whether this hy drocarbon (HC) fluorescent dye is preferentially dissolved in the HC i sland phase in phase-separated mixed monolayers of HC and fluorocarbon (FC) amphiphiles. The SNFM image clearly shows that the modified SNOM -AFM can be used to observe fluorescence and topography images. The im age also confirms the preferential dissolution of CD in the HC phase. (C) 1998 Elsevier Science B.V. All rights reserved.