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Juices, wines, and extracts from plants contain high concentrations of various chiral compounds such as carboxylic acids or sugars. Several prior studies reported the synthesis of metallic and semiconducting nanoparticles relying on components of complex biological solutions. Herein, we present preparation of chiral CdS and CdSe quantum dots (QDs) using apple juice and red wine via phase transfer ligand exchange. Although both apple juice and red wine contain a complex mixture of chiral and achiral compounds, we have successfully used them for selective induction of predicted chiroptical properties and confirmed L‐malic acid from the apple juice and L‐tartaric acid from the red wine as the chiral inducers. This work illustrates the capability of using complex mixtures to construct chiral QDs with desired chiroptical properties as well as potential of QDs to selectively report a chiral molecule in a complex chiral mixture without the need for elaborate chiral recognition system. [ABSTRACT FROM AUTHOR]

[Display omitted] The functionalization of semiconductor nanocrystals, quantum dots (QDs), with small organic molecules has been studied extensively to gain better knowledge on how to tune the electronic, optical and chiroptical properties of QDs. Chiral QDs have progressively emerged as key materials in a vast range of applications including biosensing and biorecognition, imaging, asymmetric catalysis, optoelectronic devices, and spintronics. To engage the full potential of the unique properties of chiral nanomaterials and be able to prepare them with tailorable chiroptical characteristics, it is essential to understand how chirality is rendered from chiral molecular ligands at the surface of nanocrystals to the electronic states of QDs. Using a series of polar protic and aprotic solvents together with ammonium (NH 4 +), tetramethylammonium (TMA+), and tetrabutylammonium (TBA+) countercations in the preparation of threonine-functionalized cadmium sulfide (Thr-CdS) QDs by phase transfer ligand exchange approach, we demonstrated the significance of the role both the solvent and the countercations play in the transfer of chirality from chiral molecular ligand to achiral semiconductor QDs as apparent by the modulations of the signatures and anisotropy of the circular dichroism (CD) spectra. Moreover, we have utilized tetrabutylammonium countercation to successfully synthesize chiral QDs in nonpolar cyclohexane solvent for the first time. This study provides further insights into the origin of the ligand induced chirality of colloidal nanomaterials and facilitates the synthesis of tailormade chiral QDs. [ABSTRACT FROM AUTHOR]

A complex and well-organized network of non-covalent bonds (also known as supramolecular interactions) is the foundation of the immense functional and structural diversity of biological systems. Chirality can be found at the center of almost all biological processes as clearly evidenced by the homochirality of the biological world. Stereoselective interactions are responsible for the self-assembly of macromolecules, biomolecular recognition, as well as cellular machinery and communication. Non-covalent interactions are also ideally suited for the construction of bio-inspired artificial nanoarchitectures with prescribed properties and functions. Nucleic acids (NAs) proved to be valuable chiral scaffolds for precise arrangement of desired molecular components into chiral, periodically patterned nanosystems. Single stranded NAs (ssDNA and ssRNA) are particularly suitable for templated supramolecular bottom-up nanoassembly. In this review article, we describe the progress in using the homochiral ssDNA and ssRNA as templates to assemble molecular components into chiral double-zipper supramolecular nanostructures via non-covalent interactions ( i.e. , hydrogen and coordination bonding, electrostatic and π–π stacking interactions) and discuss their chiroptical and structural properties. We outline the challenges in controlling the handedness of ssNA templated assemblies as well as challenges in accessing either of two helical geometries using the same ssNA template. We discuss empirical methods and theoretical simulations for determination of the handedness as well as chiroptical and structural properties of templated assemblies. We highlight higher order architectures of chiral ssNA templated nanoassemblies as detected by atomic force and transmission electron microscopies (AFM and TEM). [ABSTRACT FROM AUTHOR]