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  • Capture of Phenylalanine and Phenylalanine-Terminated Peptides Using a Supramolecular Macrocycle for Surface-Enhanced Raman Scattering Detection
Title: Capture of Phenylalanine and Phenylalanine-Terminated Peptides Using a Supramolecular Macrocycle for Surface-Enhanced Raman Scattering Detection
The cucurbit[n]uril (CB[ n]) family of macrocycles are known to bind a variety of small molecules with high affinity. These motifs thus have promise in an ever-growing list of trace detection methods. Surface-enhanced Raman scattering (SERS) detection schemes employing CB[ n] motifs exhibit increased sensitivity due to selective concentration of the analyte at the nanoparticle surface, coupled with the ability of CB[ n] to facilitate the formation of well-defined electromagnetic hot spots. Herein, we report a CB[7] SERS assay for quantification of phenylalanine (Phe) and further demonstrate its utility for detecting peptides with an N-terminal Phe. The CB[7]–guest interaction improves the sensitivity 5–25-fold over direct detection of Phe using citrate-capped silver nanoparticle aggregates, enabling use of a portable Raman system. We further illustrate detection of insulin via binding of CB[7] to the N-terminal Phe residue on its B-chain, suggesting a general strategy for detecting Phe-terminated peptides of clinically relevant biomolecules.  more » « less
Award ID(s):
1709566
PAR ID:
10300923
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Applied Spectroscopy
Volume:
74
Issue:
11
ISSN:
0003-7028
Page Range / eLocation ID:
1374 to 1383
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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