Stimuli-Responsive Self-Immolative Polymer Nanofiber Membranes Formed by Coaxial Electrospinning

The first self-immolative polymer (SIP) nanofiber membrane is demonstrated in this report, in which the immolation can be triggered by external stimulus. Electrospun SIP/polyacrylonitrile (PAN) fibers provide depolymerization that is ∼25 times quicker and more responsive (i.e., immolation) than that of a cast film in the triggering condition. Depolymerization of SIP in the SIP/PAN blended fiber membrane results in the transition of the surface properties from hydrophobic (∼110°) to hygroscopic (∼0°). Triggered release of encapsulated functional molecules was demonstrated using coaxially electrospun fiber membrane made of a SIP/PAN blend sheath and polyvinylpyrrolidone/dye core. Coaxial fibers with the SIP/PAN sheath provide minimal release of the encapsulated material in nontriggering solution, while it releases the encapsulated material instantly when the triggering condition is met. Its versatility has been strengthened compared to that of non-SIP coaxial fibers that provide no triggering reaction by external stimulus

(A) The HPMA-DMAEMA copolymer used for DNA delivery in both <i>in vitro</i> and <i>in vivo</i> studies. (B) Maps of the CMV-eGFP and Trophoblast-specific plasmids.

<p>(A) The HPMA-DMAEMA copolymer used for DNA delivery in both <i>in vitro</i> and <i>in vivo</i> studies. (B) Maps of the CMV-eGFP and Trophoblast-specific plasmids.</p

GFP expression in Human uterine fibroblasts after transfection with nanoparticles containing (A) CMV-GFP, (B) PLAC1-GFP or (C) CyP19a-923-GFP. HEK293 cells transfected with (D) CMV-GFP, (E) PLAC1-GFP or (F) CyP19a-923-GFP demonstrated low but visible transgene expression under the CMV promoter but no GFP expression with the trophoblast-specific promoters. GFP expression in HPMVECs cells after transfection with nanoparticles containing (G) CMV-GFP, (H) PLAC1-GFP or (I) CyP19a-923-GFP. Representative images seen on 4 different passages for each cell type.

<p>Cell nuclei are stained with Dapi (blue).</p

Representative images of (A) GFP expression following transfection of BeWo with plasmid alone or (B) CMV-eGFP nanoparticles demonstrate greater transgene expression following complex formation than plasmid alone. (C) GFP expression in BeWo cells after transfection with nanoparticles containing PLAC1-GFP or (D) CyP19a-923-GFP for 4 days, resulted in comparable transgene expression to the global CMV promoter, similar results were seen on 4 different passages. Cell nuclei are stained with Dapi (blue). Proliferation levels (E) and apoptosis levels (F) in BeWo cells were not changed when cells were incubated with nanocomplexes for 48 hours compared to BeWo cells incubated with eGFP plasmid alone for the same time period, mean +/- SEM, n>4 passages per treatment.

<p>Representative images of (A) GFP expression following transfection of BeWo with plasmid alone or (B) CMV-eGFP nanoparticles demonstrate greater transgene expression following complex formation than plasmid alone. (C) GFP expression in BeWo cells after transfection with nanoparticles containing PLAC1-GFP or (D) CyP19a-923-GFP for 4 days, resulted in comparable transgene expression to the global CMV promoter, similar results were seen on 4 different passages. Cell nuclei are stained with Dapi (blue). Proliferation levels (E) and apoptosis levels (F) in BeWo cells were not changed when cells were incubated with nanocomplexes for 48 hours compared to BeWo cells incubated with eGFP plasmid alone for the same time period, mean +/- SEM, n>4 passages per treatment.</p

Offspring birthweights at delivery were the same in Sham-operated, Internal control and UABL + PLAC1-HuIGF-1 nanoparticle treated group, however the Uterine Artery Branch Ligation, and Cyp19a-HuIGF-1 nanoparticle treated groups had significantly lower birthweights.

<p>N>6 dams per group, ANOVA<0.001, post-hoc Tukeys *<0.05, **<0.01.</p

Placental morphology in the Labyrinthine (L) zone in (A) Sham, (B) UABL,(C) NP-PLAC1-hIGF-1treated groups is similar whereas differences in morphology can be seen in the NP-Cyp19a-hIGF-1 (D) treated group. (Magnification 40X). (E) The ratio of placental Junctional zone (Jz) area to Labyrinthine zone (Lz) area demonstrates significant expansion of the junctional zone in placentas treated with NP-Cyp19a-hIGF-1.

<p>Placental morphology in the Labyrinthine (L) zone in (A) Sham, (B) UABL,(C) NP-PLAC1-hIGF-1treated groups is similar whereas differences in morphology can be seen in the NP-Cyp19a-hIGF-1 (D) treated group. (Magnification 40X). (E) The ratio of placental Junctional zone (Jz) area to Labyrinthine zone (Lz) area demonstrates significant expansion of the junctional zone in placentas treated with NP-Cyp19a-hIGF-1.</p

Oligonucleotide primers for RTqPCR.

<p>Oligonucleotide primers for RTqPCR.</p