Biological Thermal Performance of Organic and Inorganic Aerogels as Patches for Photothermal Therapy

Abstract

Aerogels are materials with unique properties, among which are low density and thermal conductivity. They are also known for their exquisite biocompatibility and biodegradability. All these features make them attractive for biomedical applications, such as their potential use in photothermal therapy (PTT). This technique is, yet, still associated with undesirable effects on surrounding tissues which emphasizes the need to minimize the exposure of healthy regions. One way to do so relies on the use of materials able to block the radiation and the heat generated. Aerogels might be potentially useful for this purpose by acting as insulators. Silica- and pectin-based aerogels are reported as the best inorganic and organic thermal insulators, respectively; thus, the aim of this work relies on assessing the possibility of using these materials as light and thermal insulators and delimiters for PTT. Silica- and pectin-based aerogels were prepared and fully characterized. The thermal protection efficacy of the aerogels when irradiated with a near-infrared laser was assessed using phantoms and ex vivo grafts. Lastly, safety was assessed in human volunteers. Both types presented good textural properties and safe profiles. Moreover, thermal activation unveils the better performance of silica-based aerogels, confirming the potential of this material for PTT.

Functional Characterization and Toxicity of Pectin from Red Chilto Fruit Waste (Peels)

“…With the highest concentration tested (50 mg/mL, 5%), the viability of A. salina and C. elegans was practically unaffected. Ferreira-Gonçalves [ 68 ] evaluated the toxicity of different concentrations of apple pectin and observed that those above 3% (wt.) had high mortality rates on A. salina .…”

Highlighted Advances in Therapies for Difficult-To-Treat Brain Tumours Such as Glioblastoma

“…The materials for PTAs vary from metallic nanostructures of gold and copper to carbon and graphene nanostructures, polymer nanoparticles, and so on; they are sensitive to different laser wavelengths [ 123 , 124 , 125 ]. PTT can be associated with unwanted damage to surrounding healthy tissues, but delimitation of the light beam can be achieved via optical systems or blocking with insulating materials, such as aerogels [ 126 ].…”

Emerging Trends in Nanotechnology: Aerogel-Based Materials for Biomedical Applications

“…In some instances, the original aerogel has needed to be modified using more biocompatible elements to prevent toxicity. Consequently, non-invasive disease detection tests must be undertaken, not only to exclude any possible hazardous occurrence and describe the safe dosage but also to enhance the design of the aerogel and boost its biocompatibility [ 202 ].…”