Figure 1.

Overview of PLA film preparation and degradation experiment. (a) Compounds of the polymer film: poly (l-lactic acid) (PLA) and fluorescent nanodiamonds (FNDs). (b) FND sensors are embedded in the polymer by simple mixing, and spin-coating is used to produce a thin film. (c) The PLA film containing nanodiamond sensors is immersed in a degradation medium, which contains Gd³⁺. When the film is degraded, Gd³⁺ (green dots) can come closer to the nanodiamonds and thus leads to an increase in spin noise, which can be detected by a home-made magnetometry setup. (d) Particle tracking is used to evaluate polymer degradation in real time.