Phenolic film engineering for template-mediated microcapsule preparation

Abstract

Microcapsules are of scientific and technological interest because of their ability to encapsulate cargo inside their hollow interiors, thereby separating and protecting the cargo from the external environment. Both template-free and -mediated strategies have been exploited to prepare microcapsules. For the latter strategy, coating sacrificial particulate templates with robust films is a key step towards obtaining mechanically-stable hollow architectures following template removal. In this review, we focus on phenolic-based film engineering techniques utilizing dopamine (DA) and tannic acid (TA), which have recently emerged as new platforms for template-mediated capsule preparation. The first part of the review describes the selfpolymerization of DA, which preferentially occurs at interfaces. The second part of the review describes TA capsules. Particular emphasis is placed on the coordination-triggered rapid deposition of TA on different substrates. These examples highlight the versatility and simplicity of phenolic film engineering strategies for microcapsule preparation. Phenolics are abundant bio-based materials, and thus form an attractive field of research for the future development of microcapsules.

Supramolecular Stimuli‐Responsive Microgels Crosslinked by Tannic Acid

“…The physically crosslinked PVCL/TA microgels can be very attractive for different applications not only because of the biocompatibility of the building blocks but also due to their responsiveness to environmental changes. The pH‐sensitivity of TA‐assembled materials has been studied strongly in the last years . In an exploratory manner, we investigated the pH‐triggered degradation of the PVCL/TA‐microgels (0.5 mol%).…”

“…The pH-sensitivity of TA-assembled materials has been studied strongly in the last years. [14,19,[31][32][33][34] In an exploratory manner, we investigated the pH-triggered degradation of the PVCL/TA-microgels (0.5 mol%). The pH of the aqueous solution was increased from 6 to 12 by adding NaOH and the pH and turbidity changes were monitored ( Figure 4b).…”

Stimuli‐Responsive Tannin–FeIII Hybrid Microcapsules Demonstrated by the Active Release of an Anti‐Tuberculosis Agent

“…[13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] With respect to administration, especially to the human body,i deally such capsules should be fabricated based on ab iocompatibleb iodegradablep olymer consisting of an amphiphilic backbonet hat gives the possibility to bind equally efficiently to the hydrophobic core and cover it but also to have ah igh affinity to water. [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] With respect to administration, especially to the human body,i deally such capsules should be fabricated based on ab iocompatibleb iodegradablep olymer consisting of an amphiphilic backbonet hat gives the possibility to bind equally efficiently to the hydrophobic core and cover it but also to have ah igh affinity to water.…”

Domino games: Controlling structure and patterns of carbon nanomaterials in 2D & 3D

“…metal center and carbonizeable framework get separated rather early in the process. The recent (re-)focus on phenolic systems as scaffolding entities is therefore rather exciting [51]. Phenols are in addition redox active (2. design rule), naturally abundant (tannins in red wine or tee) and thus potentially suitable for large scale production.…”