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Title: Mechanical unfolding of ensemble biomolecular structures by shear force
Mechanical unfolding of biomolecular structures has been exclusively performed at the single-molecule level by single-molecule force spectroscopy (SMFS) techniques. Here we transformed sophisticated mechanical investigations on individual molecules into a simple platform suitable for molecular ensembles. By using shear flow inside a homogenizer tip, DNA secondary structures such as i-motifs are unfolded by shear force up to 50 pN at a 77 796 s −1 shear rate. We found that the larger the molecules, the higher the exerted shear forces. This shear force approach revealed affinity between ligands and i-motif structures. It also demonstrated a mechano-click reaction in which a Cu( i ) catalyzed azide–alkyne cycloaddition was modulated by shear force. We anticipate that this ensemble force spectroscopy method can investigate intra- and inter-molecular interactions with the throughput, accuracy, and robustness unparalleled to those of SMFS methods.  more » « less
Award ID(s):
1904921
PAR ID:
10331931
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Chemical Science
Volume:
12
Issue:
30
ISSN:
2041-6520
Page Range / eLocation ID:
10159 to 10164
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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