proteins, present bioactive ligands to cells, and degrade at a tunable
rate [10e12]. Furthermore, ionically crosslinked alginates have
been used extensively for drug delivery, cell encapsulation, and
tissue engineering because ionic crosslinking can be largely benign
to cells and encapsulated molecules [13].
The encapsulation of various small molecules, proteins, and cells
in alginate hydrogels has thus far been largely limited to the
reversible ionic crosslinking method which uses divalent cations,
such as Ca2þ, to form ionic bridges between adjacent polymer
chains. These gels have been shown to be weak and to lose mechanical
integrity over time in vitro and in vivo due to the reversible
nature of the crosslinking and subsequent outward flux of ions from
the hydrogel [14]. Calcium crosslinked alginate gels can yield nonuniform
physical properties, due to extremely rapid crosslinking
with certain ions [15]. Moreover, leached calcium from calcium
crosslinked alginate gels can be immunostimulatory, which is unfavorable
in many in vivo applications [16]. While alginate is well
proteins, present bioactive ligands to cells, and degrade at a tunablerate [10e12]. Furthermore, ionically crosslinked alginates havebeen used extensively for drug delivery, cell encapsulation, andtissue engineering because ionic crosslinking can be largely benignto cells and encapsulated molecules [13].The encapsulation of various small molecules, proteins, and cellsin alginate hydrogels has thus far been largely limited to thereversible ionic crosslinking method which uses divalent cations,such as Ca2þ, to form ionic bridges between adjacent polymerchains. These gels have been shown to be weak and to lose mechanicalintegrity over time in vitro and in vivo due to the reversiblenature of the crosslinking and subsequent outward flux of ions fromthe hydrogel [14]. Calcium crosslinked alginate gels can yield nonuniformphysical properties, due to extremely rapid crosslinkingwith certain ions [15]. Moreover, leached calcium from calciumcrosslinked alginate gels can be immunostimulatory, which is unfavorablein many in vivo applications [16]. While alginate is well
การแปล กรุณารอสักครู่..
