9
A P P L I C A T I O N N O T E
Figure 6: (A) DLS analysis of copolymer nanodisc-stabilized GLP1R. The cumulant analysis reported the polydisper-
sity index (PDI) of the sample to be 0.06 ± 0.02. The size distribution analysis reported the hydrodynamic radius (rH)
of the GLP1R nanodisc to be 5.51 ± 0.12 nm. (B). Binding of Exendin (9-39) to nanodisc-stabilized GLP1R. The fluo-
rescently labeled GLP1R was used at a constant concentration of 20 nM with varying concentrations of the Exendin
(9-39) in 20 mM HEPES pH 7, 150 mM NaCl, and 0.005% Tween 20. Ratios of the fluorescence intensities at 670 and
650 nm were used for interaction analysis yielding the Kd of 4.51 nM with S/N ratio of 10.1. Error bars represent the
standard deviation of 3 independent measurements and with a confidence of 95%, Kd is within 1.79-5.91 nM.
The copolymer nanodisc-stabilized full-length GPCR, GLP1R, was found to be highly mon-
odisperse and thermally stable. Using this high-quality protein sample, the Spectral Shi
measurement was successfully employed to study the binding of a peptide to the membrane
nanodiscs in the assay buffer without further optimization steps. The Monolith X is designed
for user-friendly operation, offering a straightforward assay setup and intuitive so ware
that provides detailed guidance to users. This ease of use makes interaction analysis ac-
cessible to interdisciplinary scientists and enables biophysical experts to be more efficient,
especially when working with challenging protein targets.
0
2
4
6
8
10
12
14
16
Relative
probability
1 10 100 1000
Radius [nm]
0.88
0.9
0.92
0.94
0.96
0.98
1
1.02
670nm
/
650nm
1x10
-11
1x10
-10
1x10
-9
1x10
-8
1x10
-7
1x10
-6
1x10
-5
Ligand Concentration [M]
(A) (B)