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In this paper, we describe the synthesis of new chiral nanosized surfaces based on chiral self-assembled monolayers coated with metal oxide (Al 2 O 3 ) nanolayers. In this new type of nanosized chiral surface, the Al 2 O 3 nanolayers enable the protection of the chiral self-assembled monolayers while preserving their enantioselective nature. The chiral nature of the SAMs/Al 2 O 3 films was characterized by a variety of techniques, such as, quartz crystal microbalance, circular dichroism (CD) spectroscopy and chiral crystallization. The proposed methodology for the preparation of nanoscale chiral surfaces described in this article could open up opportunities in other fields of chemistry, such as chiral catalysis. [ABSTRACT FROM AUTHOR]

The control over crystal polymorphism is a well-established subject in crystallization and materials chemistry. In recent years, self-assembled monolayers (SAMs) with different functionalized groups have been used as a new chemical approach to control crystal nucleation and polymorphism. In this paper, we focus on a study of the different mechanisms involved in polymorphism control by crystallization onto SAMs. We study the crystallization of l-glutamic acid on SAMs with various functionalized end groups: R–OH, R–CH3 and R–COOH. Furthermore, in this work we select crystallization conditions in which we can identify different mechanisms of polymorphism stabilization and show that functionalized SAMs can be used to stabilize crystal polymorphism by means of crystal adsorption from the crystallization solution onto SAMs, and not merely by nucleation and crystal growth onto the SAMs. [ABSTRACT FROM AUTHOR]

In this paper, we describe for the first time the synthesis of new chiral nanosized metal oxide surfaces based on chiral self-assembled monolayers (SAMs) coated with metal oxide (TiO2) nanolayers. In this new type of nanosize chiral surface, the metal oxide nanolayers enable the protection of the chiral self-assembled monolayers while preserving their enantioselective nature. The chiral nature of the SAM/TiO2 films was characterized by variety of unique techniques, such as second-harmonic generation circular dichroism (SHG-CD), quartz crystal microbalance, and chiral adsorption measurements with circular dichroism spectroscopy. The chiral resolution abilities of the SAMs coated with metal oxide (TiO2) nanolayers were investigated in the crystallization of a racemic mixture of threonine and glutamic acid. Our proposed methodology for the preparation of nanoscale chiral surfaces described in this article could open up opportunities in other fields of chemistry, such as chiral catalysis. [ABSTRACT FROM AUTHOR]