Clay/polymer composite materials have become increasingly popular in biomedical applications, including drug delivery, tissue engineering, cosmetics and fabrication of cell capturing surfaces. It is crucially important to investigate the biological effects of these materials, establishing their biocompatibility, toxicity range, biodistribution and uptake mechanisms. In addition, the self-assembly pathways and patterns should also be carefully investigated, as these directly affect the functional properties of the materials. Convectional microscopy techniques, such as optical and electron microscopies, are limited by either resolution or sample preparation requirements. As a result, novel approaches are required for effective and rapid imaging and analysis of clay/polymer based materials and their interactions with biological entities. In this talk, the recent results on imaging and characterisation of polymer/halloysite (and other clay) composites using three “less traditional” microscopy techniques, namely dark-field hyperspectral, 3D non-fluorescent confocal laser scanning and PeakForce Tapping atomic force microscopies are reported. The traditional microscopy techniques, such as fluorescence and electron microscopies, were also used in correlative mode to confirm observation with the novel techniques. The use of these technique is illustrated with a number of examples, such as cellular uptake and localisation in cytoplasm, in situ drug release and detection of clay particles on cellular membranes and within live invertebrates. The results on 3D imaging and quantitative characterisation of surface roughness parameters of polymer-modified halloysite nanotubes on glass surfaces and hair cuticles are reported. In addition, dynamic imaging of clay nanotubes uptake by live human cells and Caenorhabditis nematodes is discussed.

Examining cellular uptake and self-assembly of clay/polymer composites in situ with “less traditional” microscopy techniques

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.