8 research outputs found
Preparing mono-dispersed liquid core PDMS microcapsules from thiol–ene–epoxy-tailored flow-focusing microfluidic devices
A dual-cure system based on thiol–ene and thiol–epoxy “click chemistry” reactions proved to be an effective and easy to use tool for microfluidic chips, which provides control over material properties and enables covalently bonding of chip wafers.</p
Glycerol-silicone elastomers as active matrices with controllable release profiles
Drug
release regimes must be controlled for the optimal therapeutic
effect. Although it is relatively straightforward to create first-order
release matrices, it can be challenging to avoid an initial burst.
Matrices with zero-order profiles are perceived to be beneficial in
many cases but are even more difficult to formulate. We describe the
straightforward synthesis of elastomeric composites prepared from
silicone in which the active substance is dispersed in glycerol. The
release of glycerol-soluble actives from the films of these materials
was shown to be tunable with respect to the order of release (zero-
or first-order) simply by changing the glycerol content. Importantly,
release from the elastomers showed no burst effect. The discrete glycerol
domains embedded within a silicone matrix act as reservoirs for active
substances. Upon contact with aqueous media, the active substances
are released from the matrices exhibiting zero-order, near zero-order,
or first-order release kinetics. Various parameters that could influence
the release process, including glycerol content, glycerol domain size,
or membrane thickness, are thoroughly investigated, elucidating guidelines
for creating matrices capable of delivering the active substances
at desired rates. Additionally, the composites proved to absorb significant
amounts of liquid water (up to 1850% of sample mass), a feature that
can be tuned by the manipulation of the composite structure