Afterglow-driven tablet quality assessment (Ⅱ): edible ultralong organic phosphorescent sodium carboxymethyl...

Sodium carboxymethyl cellulose, an edible ultralong organic room-temperature phosphorescent excipient, was employed to formulate anti-counterfeit ink for tablets. A series of anti-counterfeit patterns on diverse tablet shapes were formed through spraying. The anti-counterfeit tablets were examined for afterglow imaging, phosphorescence lifetime, and the effects of temperature and humidity on their afterglow patterns. Findings show: Excitation at 254 nm and 365 nm gives maximum absorption wavelengths of 501 nm and 470 nm for the anti-counterfeit inks, respectively; At 254 nm excitation, phosphorescence lifetime variances for flower, heart, and moon patterns across different tablet shapes are 4.69 %, 5.96 %, and 7.10 %, respectively. At 365 nm, the values are 6.34 %, 12.1 % and 28.05 %, respectively. The phosphorescence lifetime differences among different anti-counterfeiting patterns at 254 nm and 365 nm are less than 7.56 % and 26.52 %, respectively. As relative humidity increased from 23 % to 94 %, the phosphorescence lifetime decreased by 61.85 %. When temperature increased from 0 °C to 40 °C, the afterglow image's color shifted from blue to yellow-green, and the afterglow duration was reduced by 53.48 %; The ambient environment doesn't significantly influence long-term afterglow stability. This work successfully prepared anti-counterfeiting tablets with afterglow, providing key insights for optimizing pattern design and storage conditions for practical anti-counterfeit applications.