Evaluation of Chemical Interactions between Small Molecules in the Gas Phase Using Chemical Force Microscopy

Sensors

Jieun Lee³  Soomi Ju³  In Tae Kim³  Sun-Hwa Jung⁵  Sun-Joon Min⁴  Chulki Kim¹  Sang Jun Sim²  Sang Kyung Kim³ 

[1] Center for Sensor System Research, Korea Institute of Science and Technology (KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Korea;Department of Chemical and Biological Engineering, Korea University, 5-ga Annam-dong, Seongbuk-gu, Seoul 136-713, Korea;Center for Biomicrosystems, Korea Institute of Science and Technology (KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Korea;Department of Applied Chemistry, Hanyang University, Sangnok-gu, Ansan, Gyeonggi-do 15588, Korea;Center for Neuro-Medicine, Brain Science Institute, Korea Institute of Science and Technology(KIST), Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791, Korea;

关键词: chemical force microscopy;    micro-contact printing;    lateral force image;    benzene specific peptide;   

DOI  :  10.3390/s151229823

来源: mdpi

【 摘 要 】

Chemical force microscopy analyzes the interactions between various chemical/biochemical moieties in situ. In this work we examined force-distance curves and lateral force to measure the interaction between modified AFM tips and differently functionalized molecular monolayers. Especially for the measurements in gas phase, we investigated the effect of humidity on the analysis of force-distance curves and the images in lateral force mode. Flat chemical patterns composed of different functional groups were made through micro-contact printing and lateral force mode provided more resolved analysis of the chemical patterns. From the images of 1-octadecanethiol/11-mercapto-1-undecanoic acid patterns, the amine group functionalized tip brought out higher contrast of the patterns than an intact silicon nitride tip owing to the additional chemical interaction between carboxyl and amine groups. For more complex chemical interactions, relative chemical affinities toward specific peptides were assessed on the pattern of 1-octadecanethiol/phenyl-terminated alkanethiol. The lateral image of chemical force microscopy reflected specific preference of a peptide to phenyl group as well as the hydrophobic interaction.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.