Multimode 8 afm instrument

A Bruker Multimode 8
AFM instrument (Billerica, Massachusetts, USA) was used to acquire
AFM images to determine the thickness of the NHA (Figure S2) and to investigate the morphology of the polyNIPAM
monolayer on a surface (Figure S7). Cantilevers
for measurements were ScanAsyst Air with a resonance frequency of
70 kHz and a force constant of 0.4 N/m for dry conditions and ScanAsyst
Fluid with a resonance frequency of 150 kHz and a force constant of
0.7 N/m for liquid conditions. All measurements were carried out with
the ScanAsyst tapping mode. For liquid measurements, 20 μL of
H₂O was dropped on the sample and the tip was completely
immersed.

UV–vis spectra were recorded
using either Varian Cary 300 (Agilent) (400–900 nm) spectrophotometer
or StellarNet (StellarNet Inc, Florida) (200–1080 nm) systems.
Atomic force microscopy (AFM) measurements were collected using
the amplitude-modulated (peak force tapping) mode of a multimode-8
AFM instrument (Bruker, Santa Barbara, CA). Digital transmission electron
microscopy (TEM) was done with a Thermo Scientific Talos L120C (Experimental
details in Supporting Information). Crystal
sizes of seeds and stars were determined with powder X-ray diffraction
(XRD), using a Bruker D8 ADVANCE with a Lynx-Eye strip detector. The
seeds and stars were prepared and then washed with water to remove
polymers (Experimental details in Supporting Information).