2.3.1. Di fferential Scanning Calorimetry

Approximately 4 mg of filtered and air-dried OPT-NCC (to constant mass) was placed into an aluminum pan and sealed. The pan was then placed directly into the furnace of a DSC 6000 PerkinElmer Di fferential Scanning Calorimeter (Waltham, MA, USA) and the data generated was analyzed using version 11 Pyris ™ Manager Software (PerkinElmer). The temperature of the DSC was monitored with a computer and a controlled heating rate of 10 K/min was used for the analysis over the temperature range 30–150 ◦C. All DSC analyses were conducted in triplicate (*n* = 3) under a nitrogen atmosphere purged at a flow rate of 20 mL/min and the thermogram for the micro co-crystal (uncoated) was used as a reference.

### 2.3.2. Energy-Dispersive X-ray Spectroscopy Scanning Electron Microscopy

Elemental analysis was performed using a Vega ® Scanning Electron Microscope (TESCAN, Brno, Czechia) fitted with an INCA PENTA FET. Approximately 1 mg of the OPT-NCC was dusted onto a graphite plate and the sample irradiated at an accelerated voltage of 20 kV (*n* = 3).
