![]() ![]() This is one of the current challenges in biophysics, which raised questions on the emergence of RNA 3. RNA has been reported to spontaneously replicate in a homochiral system, but this replication can be blocked by the presence of the opposing enantiomers. Importantly, building blocks of life 2, such as proteins, nucleic acids, glycans, and lipids are dominated by an asymmetrically distributed number of enantiomers. Many naturally occurring molecules, with amino acids being prominent examples, are chiral. ![]() In chemistry, chiral molecules are defined as left- or right-handed enantiomers forming sets of stereoisomers. The terms chiral and chirality originally stem from geometry and were defined by Lord Kelvin as “ I call any geometrical figure, or group of points, chiral, and say that it has chirality if its image in a plane mirror, ideally realized, cannot be brought to coincide with itself.” 1 In this terminology, chirality refers purely to the object’s geometry and does not necessarily infer any information on the physical and chemical properties of a chiral material. We then consider emerging applications of chiral carbon dots in sensing, bioimaging, and catalysis, and conclude this review with a summary and future challenges. In the main part of this review we focus on chiral carbon dots, introducing their fabrication techniques such as bottom-up and top-down chemical syntheses, their morphology, and optical/chiroptical properties. Then approaches used to induce chirality in nanomaterials are reviewed. We start this review by introducing examples of molecular chirality and its origins and providing a summary of chiroptical spectroscopy used for its characterization. ![]() In recent years, synthetic efforts leading to chiral carbon dots with other attractive optical properties such as two-photon absorption and circularly polarized light emission have flourished. (g) This compound does not contain asymmetric carbon atom and is an achiral compound.Carbon dots are luminescent carbonaceous nanoparticles that can be endowed with chiral properties, making them particularly interesting for biomedical applications due to their low cytotoxicity and facile synthesis. The compound gives a different or non-superimposable mirror image to that of the original object.Ĭhirality axis is shown where the substituents are different on each ring. (f) This compound does not contain asymmetric carbon atom but it is chiral since it has different ortho substituents on each ring. It gives a different or non-superimposable mirror image to that of the original object, (e) This compound contain an asymmetric carbon atom and it is chiral. (d) does not contain asymmetric carbon atom and is an achiral compound. The compound gives a different or non-superimposable mirror image to that of the original object. (c) does not contain asymmetric carbon atom but it is chiral. (b) does not contain asymmetric carbon atom but it is chiral. The compound gives a different or non-superimposable mirror image to that of the original object.This kind of chirality is known as axial chirality. ![]() (a) does not contain asymmetric carbon atom but it is chiral. If the two groups one end of the allene are different and the two groups on the other end of the allene are different, then the allene is called as chiral.īiphenyls are considered to be chiral if the substituents at the ortho position are larger in size and must contain different ortho substituents on each ring. ![]()
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