film thicknesses. These films exhibit low surface roughness and
film densities comparable to LbL films. Applied to particle
templates, CAPATRP affords robust hollow capsules or particle
replicas following template removal. ATRP allows facile
single-step CAP film formation at room temperature without
stringent air-free conditions and supports the utilisation of a
wide range of pendant vinylic functionalised macrocross-
linkers to afford compositionally diverse films. Current studies
are focused on applying the CAP process to macrocross-
linkers with complex architectures to prepare films not readily
accessible via traditional grafting approaches, as well as the
application of the CAP approach towards the development of
nanoengineered films and particles for a range of applications,
ranging from membranes to drug delivery.
Fig. 3 (a) Fluorescence intensity evolution of film growth on SiO2
particles after each CAPATRP step, as followed by flow cytometry.
(b) Fluorescence microscopy images of P(HEA-co-MOEA)-FITC
capsules in solution after 4 reinitiation and CAPATRP steps; inset
corresponds to a bright field microscopy image. P(HEA-co-MOEA)
capsules in dehydrated states by (c) SEM and (d) AFM. Fluorescence
microscopy images of (e) MS particles coated with a single CAPATRP
film of P(HEA-co-MOEA)-FITC and (f) polymeric replica spheres
obtained after template removal; insets show corresponding bright
field microscopy images. Scale bars are 5 mm (b, e, f) and 2 mm (c, d).
This work was supported by the Australian Research
Council under the Federation Fellowship (F.C., FF0776078)
and Discovery Project (F.C., G.G.Q, DP1094147) schemes.
We thank C. R. Kinnane for help with SEM.
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templates. Fluorescence intensity data obtained from flow
cytometry illustrates the continuous growth of fluorescein
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after template removal demonstrates the successful infiltration
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c
This journal is The Royal Society of Chemistry 2011
Chem. Commun., 2011, 47, 12601–12603 12603