Confocal Analysis of CNC based Hydrogels and Suspensions

Abstract

Cellulose nano crystal (CNC) hydrogels, while mechanically weak, have unique properties such as easy synthesis, high water content, and biocompatibility. Further improvement is needed to make CNC hydrogels mechanically stable and self-healable. Herein, using quantitative fluorescence recovery after photobleaching (FRAP) analysis, we assess stability, collapse, and level of self-healing of CNC hydrogels with different CNC and sodium chloride (NaCl) concentrations. We use the mean signal intensity obtained by confocal laser scanning microscopy (CLSM) to measure signal loss of the samples made of CNC hydrogels of different CNC concentrations and as a function of initial gel height and NaCl loading. The CNC dynamics inside the gels based on universality curves is unraveled which links the zeta potentials to the immobile particle percentages and the storage moduli as a function of NaCl/CNC concentration ratio. FRAP recovery analysis shows that for the ratio of NaCl/CNC beyond 0.1, the mobility of the ensemble of CNC particles becomes severely restricted. Hydrogel samples with low CNC concentrations (6 g/L and 10 g/L) experience a more substantial collapse rate under gravity than the rate observed for samples with a high CNC concentration (30 g/L). Increasing the CNC concentration hinders particle mobility and thus impedes the self-healing process. Quantification of the gel collapse behavior of CNC gel and its self-healing property is critical in many applications, including water and air filters, oil spill sponges, and tissue engineering.

Asphaltene Modeling, Emulsion, and Aggregation: A Review

“…The calcium ion, salinity, and acidity all had an impact on the adhesion strength. These results are remarkably like other nanofillers [36][37][38][39][40][41][42] . Results are depicted schematically in Figure 1 displaying how AFM came into measuring the interaction between surface of asphaltene.…”

Nanocellulose Product Design Aided by Confocal Laser Scanning Microscopy

“…Diffusion inside particle gels or suspensions can also be measured using FRAP; as stated earlier, one of the goals of particle suspension preparation is to use particles in networked states due to superior properties of the network state over the disordered state depending on an application. This part was completely discussed in the Introduction and in refs and , so we will not go into greater detail here. To summarize, we briefly covered the many systems that fall under the FRAP umbrella, as well as the governing parameters that influence cellulose-based gels, which most commonly occur from the coagulation of CNC-based nanoscale colloids such as CNCs and CNFs in the literature.…”