‘Barcodes’ for Molecules Expedite Medical Advancements
There’s now an easier way to ID unique molecules. UCF NanoScience Technology Center researchers developed a special “barcode” to identify molecules. Led by UCF NanoScience Technology Center Professor Debashis Chanda, the team developed a “barcoding” technique to identify chiral molecules based on unique infrared fingerprints quickly. Molecules can be identified using a special pixelated 2D sensor array that interacts with precise light with the specific properties of the molecules, capturing unique vibrational absorptions, which are mapped as a barcode. The study, funded by the U.S. National Science Foundation, was recently published in Advanced Materials.
Understanding the nature of chiral molecules is crucial to biological and pharmaceutical research because the mirror image pairs, or enantiomers, can each have different effects in the body or in chemical reactions. 56% of all modern drugs and medicine are chiral, and 90% of those are a mixture containing equal amounts of two enantiomers of a chiral compound. Most modern medicines and drugs are chiral and are marketed as racemates (equal mixtures of enantiomers), which in some cases can have unwanted consequences.
“On molecular adsorption, the combined system’s response depends on the degree and positional overlap of the molecule’s absorbance and sensor resonance,” Chanda says. “The measured signal is analyzed and encoded to generate a ‘chiral barcode’ for uniquely identifying the adsorbed chiral molecule. We show applicability of the platform by analyzing and generating unique chirality-based barcodes for an enantiomeric pair of small molecules, as well as a pair of spectrally similar larger chiral biomolecules based on very low volumes of analytes at ultra-low concentrations.”
The sensing platform is made of nanopatterned gold where the interactions between the plasmonic and photonic cavity modes produce strong chiral “superchiral” light. By changing the geometrical parameters, 25 spectrally de-tuned sensors in 5×5 array were produced. When a molecule is added to this array, each sensing element produces slightly different chiral response, resulting in a unique barcode.
Existing platforms require chiral nanostructures of varying asymmetries that can be difficult to replicate. The proposed system’s inherent achirality overcomes this problem, greatly simplifying the fabrication process.
