Related Experiment Video
Updated: Jul 9, 2026
08:51
Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
All-Optical Chirality-Sensitive Sorting via Reversible Lateral Forces in Interference Fields
Tianhang Zhang1,2, Mahdy Rahman Chowdhury Mahdy2,3, Yongmin Liu4
1Graduate School for Integrative Sciences and Engineering, National University of Singapore , Centre for Life Sciences (CeLS), #05-01, 28 Medical Drive, Singapore 117456, Singapore.
ACS Nano
|April 4, 2017
Summary
This study introduces an all-optical method for separating chiral molecules. Chirality-dependent optical forces enable passive sorting of these substances, offering new possibilities in chemistry and biology.
Area of Science:
- Optics
- Physical Chemistry
- Biophysics
Background:
- Chiral separation is crucial in chemistry and biology but presents significant challenges.
- Existing methods for chiral separation are often complex and inefficient.
Purpose of the Study:
- To develop an all-optical, passive method for sorting chiral objects.
- To investigate chirality-dependent lateral optical forces for separation.
Main Methods:
- Inducing lateral optical forces using interfered optical fields with controlled polarization states.
- Analyzing optical forces on chiral objects in two-plane-wave interference patterns.
- Utilizing interference at an interface between two media for chiral-selective separation.
Main Results:
- Nonzero lateral optical forces were observed for linearly and circularly polarized light, causing observable particle motion.
- While forces differed in magnitude for different chiralities, their directions were similar for opposite handedness, initially hindering separation.
- Achieved chiral-selective separation by employing more complex polarization states and interface-induced interference.
Conclusions:
- An all-optical, passive sorting technique for chiral substances has been demonstrated.
- The method leverages chirality-dependent lateral optical forces, offering a robust approach for sorting chiral molecules and biomolecules.
Related Concept Videos
02:52Stereoisomerism
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
02:25Chirality
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
02:24Properties of Enantiomers and Optical Activity
It is essential to understand the difference between chiral and achiral interactions and the implications thereof in optical activity and their applications. Just as our feet, which are chiral, interact uniquely with chiral objects, such as a pair of shoes, but identically with achiral socks, enantiomers of a molecule exhibit different properties only when they interact with other chiral media. An example of a significant implication from this facet is the phenomenon known as optical activity,...
02:05Prochirality
The concept of prochirality leads to the nomenclature of the individual faces of a molecule and plays a crucial role in the enantioselective reaction. It is a concept where two or more achiral molecules react to produce chiral products. A typical process is the reaction of an achiral ketone to generate a chiral alcohol. Here, the achiral reactant reacts with an achiral reducing agent, sodium borohydride, to generate an equimolar mixture of the chiral enantiomers of the product. For example, an...
02:30Chirality in Nature
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid. The...
01:34Woodward–Hoffmann Selection Rules and Microscopic Reversibility
Electrocyclic reactions, cycloadditions, and sigmatropic rearrangements are concerted pericyclic reactions that proceed via a cyclic transition state. These reactions are stereospecific and regioselective. The stereochemistry of the products depends on the symmetry characteristics of the interacting orbitals and the reaction conditions. Accordingly, pericyclic reactions are classified as either symmetry-allowed or symmetry-forbidden. Woodward and Hoffmann presented the selection criteria for...