Direct preparation of gelatin microcapsules on paper surface using simple coacervation technique

Abstract

A simple coacervation technique was used to coat a functional paper with gelatin microcapsules containing geraniol to prepare functional papers with sustained fragrance release. This method eliminated the need for microcapsule preparation and coating with a binder. A gelatin solution containing geraniol and Tween 20 was coacervated using sodium carbonate (Na 2 CO 3 ) solution; the final Na 2 CO 3 concentration in the solution was 5 wt %. Filter papers impregnated with the coacervation mixture were immersed in 0-20 wt % Na 2 CO 3 solutions. Gelatin microcapsules were formed on the paper surface when 15 or 20 wt % Na 2 CO 3 solutions were used. The maximum amount of geraniol was fixed on paper prepared under these conditions, and the percentage of residual geraniol in the paper (RES) was about 70% after 72 h; this value was much higher than that for a blank sheet. The formation of gelatin microcapsules was important for the fixation and sustained release of geraniol. Figure 5. Residual geraniol for gelatin microcapsules prepared on (l) blank paper, (~) reference paper prepared using geraniol-Ca(OH) 2 composite powder and binder, and papers prepared using (n) 15 wt % Na 2 CO 3 and (^) 20 wt % Na 2 CO 3 . ARTICLE WWW.MATERIALSVIEWS.COM WILEYONLINELIBRARY.COM/APP

All-Aqueous Direct Deposition of Fragrance-Loaded Nanoparticles onto Fabric Surfaces by Electrospraying

“…A closer inspection of Figure A and B reveals that, after coating with SF by electrospray, the 11-day accumulated release percentage of limonene from LimIC@tSF can be decreased by about 15 times compared to that of LimIC (2.5% vs 37.8%), whereas the total amount of rose oxide released was about 8 times lower than that of its CD complex RoseIC (1.4% vs 12.7%). This observation suggests that this CD-assisted encapsulation strategy is particularly attractive for the loading and controlled release of highly volatile fragrances. − With regard to facile and green preparation and to controlled release of aroma molecules, the sprayed SF nanoparticles outperformed the previously reported fragrant nanocapsules. , More importantly, the kinetic characteristics of the zero-order release observed for the present aroma-delivery systems are highly desirable, because they allow constant release of entrapped olfactory molecules and hence keep the smell at a certain level. , …”

“…43−46 With regard to facile and green preparation and to controlled release of aroma molecules, the sprayed SF nanoparticles outperformed the previously reported fragrant nanocapsules. 10,47 More importantly, the kinetic characteristics of the zero-order release observed for the present aromadelivery systems are highly desirable, because they allow constant release of entrapped olfactory molecules and hence keep the smell at a certain level. 48,49 Finally, we explored the feasibility of using the electrospray technique to directly adhere nanoparticles to the substrate surface, which would have great advantages in various applications such as fabric finishing.…”

Assessment of the delivery of citronella oil from microcapsules supported on wool fabrics

“…The FTIR spectrum of gelatin shows the presence of amide and amine. The bands identified are: 3,431.10 cm -1 (CONH 2 ), 1,631.71 cm -1 (primary amide C=O stretch), 1,543.40 cm -1 (secondary aromatic amide), 2,927.08 (-NH 2 ), 1,337.05(deformation C-N) and 1,078.33 cm -1 (axial deformation of the aliphatic amine C-N)[33,35].The amino group belonging to the chain of gelatin has a positive charge in the acid medium due to the presence of a protonated amino group (NH…”

Low temperature-dependence of N,N-dimethyl-3-methylbenzamide (DEET) release from a functional paper containing paraffin–DEET composites prepared using interfacial polymerization

“…Functional papers that release fragrances are useful in applications such as insecticide sheets [12,13], which can release, for example, the insect repellant N,N-dimethyl-3-methylbenzamide (DEET) [14][15][16][17], which is the focus of the work presented here. DEET is a popular insect repellent because of its high efficiency and safety.…”

“…We have recently investigated fixing functional materials without either microencapsulation or binder-coating processes [12,13,[18][19][20][21][22], including preparing functional paper using interfacial polymerization on the paper surface [12,[19][20][21]. This technique will be useful for preparing functional papers that emit DEET.…”