Lignin-Derived Carbon Dot/Cellulose Nanofiber Films for Real-Time Food Freshness Monitoring

Abstract

Herein, a facile, environmental-friendly, and sustainable strategy for efficient separation, conversion, and utilization of lignocellulose components was developed. Lignocellulose components were separated by green deep eutectic solvent (DES). The extracted lignin had potential for downstream production of aromatic chemicals and was used to synthesize lignin-doped carbon dots (CDs) in a ratiometric fluorescent probe for detecting biogenic amines (BAs) that were generated from food spoilage. The preparation of CDs provided an efficient strategy to convert biomass waste into carbon-based nanomaterials. This probe exhibited a sensitive, rapid, and linear response to BAs with a low detection limit of 0.045 μM. The retained cellulose with the crystal I structure was used to prepare cellulose nanofibers (CNFs) via oxidation and mechanical treatment. Furthermore, the CNFs were used as a matrix to fabricate CDs/CNFs films for real-time and visual food freshness monitoring. From biomass waste to rational applications, this study not only expanded the comprehensive utilization of lignocellulose in a green and environment-friendly manner but also demonstrated the prospects of CDs-based composite films in on-site monitoring of food quality and safety.

Biobased Intelligent Food-Packaging Materials with Sustained-Release Antibacterial and Real-Time Monitoring Ability

“…After 48 h at room temperature, shrimp packaged using the composite film with AAEO decays significantly slower (pH from 6.2 to 6.6) than that of the film without AAEO (pH from 6.2 to 7.1), with smaller changes in HSV (hue, saturation, value) values. Compared with the related reported studies, as shown in Figure e and Table S1, the developed intelligent food packaging materials can better monitor the freshness with significant color response (higher Δ S , Δ H , and Δ V values). − …”

Synthesis and Characterization of Amorphous Lawsone Polymer Dots for Fluorescent Applications

“…This slight bathochromic shift could be attributed the higher dipole moment and dielectric constant of DMSO (3.96 D and 47, respectively) relative to THF (1.75 D and 7.5) and acetonitrile (3.92 D and 37). The presence of DMSO could result in a small perturbation in the electronic structure on the LPD surface, which could couple with the shielded fluorophore in the core leading to a slight change in the dipole moment and the resulting emissive states. , Additionally, the LPDs were synthesized under different temperatures (Figure S4b–f), and soak times showed a nearly identical emission spectrum as shown in Figure . This could suggest that the fluorophore responsible for the observed properties is encapsulated within a polymeric structure with limited interaction with the solvent.…”

Study on the microcrystal cellulose and the derived 2D graphene and relative carbon materials

“…Spherical carbon and fullerene carbon dot 49,50 is usually fabricated from sugar, starch, and relative sugar polymers [51][52][53] . In this study the sMCCs sugar, hydrolyzed from sugarcane pith, is used to fabricate the sphere carbon.…”