3 research outputs found
Bioactive Organic Rosette Nanotubes Support Sensory Neurite Outgrowth
Regardless
of the intervention for peripheral nerve repair, slow
rates of axonal regeneration often result in poor clinical outcomes.
Thus, using new materials such as biologically inspired, biocompatible,
organic rosette nanotubes (RNTs) could provide a tailorable scaffold
to modulate neurite extension and attachment for improved nerve repair.
RNTs are obtained through the spontaneous self-assembly of a synthetic
DNA base analogue featuring the hydrogen bond triads of both guanine
and cytosine, the G∧C base. Here, we investigated the potential
of RNTs functionalized with lysine and Arg-Gly-Asp-Ser-Lys (<u>RGD</u>SK) peptide to support neural growth. We hypothesized
that (a) due to their dimensions, the RNTs would support neuron attachment,
and (b) their conjugation to the integrin-binding peptide <u>RGD</u>SK would further enhance neurite outgrowth compared
to unfunctionalized RNT. Neurite extension was examined on a variety
of RNT structures, including RNT with a lysine side chain (K1), a
mixture of the K1 and a free RGDS peptide, RNT alone, an RGDSK-functionalized
RNT, in addition to poly-d-lysine and laminin controls. Both
whole dorsal root ganglion (DRG) and single dissociated DRG neurons
were seeded onto RNT-coated substrates containing various ratios of
peptides. Analysis of neuron morphometrics showed that RNT blends
support DRG neuron attachment and neurite extension, with RGDS presentation
increasing neurite outgrowth from whole DRG by up to 47% over a 7-day
period compared to K1 alone (<i>p</i> < 0.013). In addition,
while RNTs increased the sprouting of primary neurites extending from
dissociated DRG neurons, the total neurite outgrowth per neuron remained
the same. These results show that functionalized biomimetic RNTs provide
a support for neurite growth and extension and have the ability to
modulate neuronal morphology. These results also pave the way for
the design of injectable RNT-based nanomaterials that support guided
neural regeneration following traumatic injury
Electroconductive Gelatin Methacryloyl-PEDOT:PSS Composite Hydrogels: Design, Synthesis, and Properties
Electroconductive
hydrogels are used in a wide range of biomedical
applications, including electrodes for patient monitoring and electrotherapy,
or as biosensors and electrochemical actuators. Approaches to design
electroconductive hydrogels are often met with low biocompatibility
and biodegradability, limiting their potential applications as biomaterials.
In this study, composite hydrogels were prepared from a conducting
polymer complex, polyÂ(3,4-ethylenedioxythiophene):polystyrenesulfonate
(PEDOT:PSS) dispersed within a photo-crosslinkable naturally derived
hydrogel, gelatin methacryloyl (GelMA). To determine the impact of
PEDOT:PSS loading on physical and microstructural properties and cellular
responses, the electrical and mechanical properties, electrical properties,
and biocompatibility of hydrogels loaded with 0–0.3% (w/v)
PEDOT:PSS were evaluated and compared to GelMA control. Our results
indicated that the properties
of the hydrogels, such as mechanics, degradation, and swelling, could
be tuned by changing the concentration of PEDOT:PSS. In particular,
the impedance of hydrogels decreased from 449.0 kOhm for control GelMA
to 281.2 and 261.0 kOhm for hydrogels containing 0.1% (w/v) and 0.3%
(w/v) PEDOT:PSS at 1 Hz frequency, respectively. In addition, an <i>ex vivo</i> experiment demonstrated that the threshold voltage
to stimulate contraction in explanted abdominal tissue connected by
the composite hydrogels decreased from 9.3 ± 1.2 V for GelMA
to 6.7 ± 1.5 V and 4.0 ± 1.0 V for hydrogels containing
0.1% (w/v) and 0.3% (w/v) PEDOT:PSS, respectively. <i>In vitro</i> studies showed that composite hydrogels containing 0.1% (w/v) PEDOT:PSS
supported the viability and spreading of C2C12 myoblasts, comparable
to GelMA controls. These results indicate the potential of our composite
hydrogel as an electroconductive biomaterial
Electroconductive Gelatin Methacryloyl-PEDOT:PSS Composite Hydrogels: Design, Synthesis, and Properties
Electroconductive
hydrogels are used in a wide range of biomedical
applications, including electrodes for patient monitoring and electrotherapy,
or as biosensors and electrochemical actuators. Approaches to design
electroconductive hydrogels are often met with low biocompatibility
and biodegradability, limiting their potential applications as biomaterials.
In this study, composite hydrogels were prepared from a conducting
polymer complex, polyÂ(3,4-ethylenedioxythiophene):polystyrenesulfonate
(PEDOT:PSS) dispersed within a photo-crosslinkable naturally derived
hydrogel, gelatin methacryloyl (GelMA). To determine the impact of
PEDOT:PSS loading on physical and microstructural properties and cellular
responses, the electrical and mechanical properties, electrical properties,
and biocompatibility of hydrogels loaded with 0–0.3% (w/v)
PEDOT:PSS were evaluated and compared to GelMA control. Our results
indicated that the properties
of the hydrogels, such as mechanics, degradation, and swelling, could
be tuned by changing the concentration of PEDOT:PSS. In particular,
the impedance of hydrogels decreased from 449.0 kOhm for control GelMA
to 281.2 and 261.0 kOhm for hydrogels containing 0.1% (w/v) and 0.3%
(w/v) PEDOT:PSS at 1 Hz frequency, respectively. In addition, an <i>ex vivo</i> experiment demonstrated that the threshold voltage
to stimulate contraction in explanted abdominal tissue connected by
the composite hydrogels decreased from 9.3 ± 1.2 V for GelMA
to 6.7 ± 1.5 V and 4.0 ± 1.0 V for hydrogels containing
0.1% (w/v) and 0.3% (w/v) PEDOT:PSS, respectively. <i>In vitro</i> studies showed that composite hydrogels containing 0.1% (w/v) PEDOT:PSS
supported the viability and spreading of C2C12 myoblasts, comparable
to GelMA controls. These results indicate the potential of our composite
hydrogel as an electroconductive biomaterial