14 research outputs found
Optimization of Alkyl Side Chain Length in Polyimide for Gate Dielectrics to Achieve High Mobility and Outstanding Operational Stability in Organic Transistors
Alkyl chain modification strategies in both organic semiconductors
and inorganic dielectrics play a crucial role in improving the performance
of organic thin-film transistors (OTFTs). Polyimide (PI) and its derivatives
have received extensive attention as dielectrics for application in
OTFTs because of flexibility, high-temperature resistance, and low
cost. However, low-temperature solution processing PI-based gate dielectric
for flexible OTFTs with high mobility, low operating voltage, and
high operational stability remains an enormous challenge. Furthermore,
even though di-n-decyldinaphtho[2,3-b:2′,3′-f]thieno[3,2-b]thiophene (C10-DNTT) is known to have very
high mobility as an air-stable and high-performance organic semiconductor,
the C10-DNTT-based TFTs on the PI gate dielectrics still
showed relatively low mobility. Here, inspired by alkyl side chain
engineering, we design and synthesize a series of PI materials with
different alkyl side chain lengths and systematically investigate
the PI surface properties and the evolution of organic semiconductor
morphology deposited on PI surfaces during the variation of alkyl
side chain lengths. It is found that the alkyl side chain length has
a critical influence on the PI surface properties, as well as the
grain size and molecular orientation of semiconductors. Good field-effect
characteristics are obtained with high mobilities (up to 1.05 and
5.22 cm2/Vs, which are some of the best values reported
to date), relatively low operating voltage, hysteresis-free behavior,
and high operational stability in OTFTs. These results suggest that
the strategy of optimizing alkyl side-chain lengths opens up a new
research avenue for tuning semiconductor growth to enable high mobility
and outstanding operational stability of PI-based OTFTs
Antibacterial and Hemocompatibility Switchable Polypropylene Nonwoven Fabric Membrane Surface
In
this article, a facile approach to fabricate a biofunctional polypropylene
nonwoven fabric membrane (PP NWF) with a switchable surface from antibacterial
property to hemocompatibility is presented. In the first step, a cationic
carboxybetaine ester monomer, [(2-(methacryboxy) ethyl)]-<i>N</i>,<i>N</i>-dimethylamino-ethylammonium bromide, methyl ester
(CABA-1-ester) was synthesized. Subsequently, this monomer was introduced
on the PP NWF surface via plasma pretreatment and a UV-induced graft
polymerization technique. Finally, a switchable surface from antibacterial
property to hemocompatibility was easily realized by hydrolysis of
poly(CABA-1-ester) moieties on the PP NWF surface under mild conditions.
Surface hydrolysis behaviors under different pH conditions were investigated.
These PP NWFs grafted with poly(CABA-1-ester) segments can cause significant
suppression of S. aureus proliferation;
after hydrolysis, these surfaces covered by poly[(2-(methacryloxy)
ethyl)] carboxybetaine (poly(CABA)) chains exhibited obvious reduction
in protein adsorption and platelet adhesion, and remarkably enhanced
antithrombotic properties. This strategy demonstrated that a switchable
PP NWF surface from antibacterial property to hemocompatibility was
easily developed by plasma pretreatment and UV-induced surface graft
polymerization and that this surface may become an attractive platform
for a range of biomedical applications
Facile Fabrication of Lubricant-Infused Wrinkling Surface for Preventing Thrombus Formation and Infection
Despite
the advanced modern biotechniques, thrombosis and bacterial infection
of biomedical devices remain common complications that are associated
with morbidity and mortality. Most antifouling surfaces are in solid
form and cannot simultaneously fulfill the requirements for antithrombosis
and antibacterial efficacy. In this work, we present a facile strategy
to fabricate a slippery surface. This surface is created by combining
photografting polymerization with osmotically driven wrinkling that
can generate a coarse morphology, and followed by infusing with fluorocarbon
liquid. The lubricant-infused wrinkling slippery surface can greatly
prevent protein attachment, reduce platelet adhesion, and suppress
thrombus formation in vitro. Furthermore, <i>E. coli</i> and <i>S. aureus</i> attachment on the slippery surfaces
is reduced by ∼98.8% and ∼96.9% after 24 h incubation,
relative to poly(styrene-<i>b</i>-isobutylene-<i>b</i>-styrene) (SIBS) references. This slippery surface is biocompatible
and has no toxicity to L929 cells. This surface-coating strategy that
effectively reduces thrombosis and the incidence of infection will
greatly decrease healthcare costs
Degradable Nanohydroxyapatite-Reinforced Superglue for Rapid Bone Fixation and Promoted Osteogenesis
Bone glue with robust adhesion is
crucial for treating
complicated
bone fractures, but it remains a formidable challenge to develop a
“true” bone glue with high adhesion strength, degradability,
bioactivity, and satisfactory operation time in clinical scenarios.
Herein, inspired by the hydroxyapatite and collagen matrix composition
of natural bone, we constructed a nanohydroxyapatite (nHAP) reinforced
osteogenic backbone-degradable superglue (O-BDSG) by in situ radical ring-opening polymerization. nHAP significantly enhances
adhesive cohesion by synergistically acting as noncovalent connectors
between polymer chains and increasing the molecular weight of the
polymer matrix. Moreover, nHAP endows the glue with bioactivity to
promote osteogenesis. The as-prepared glue presented a 9.79 MPa flexural
adhesion strength for bone, 4.7 times that without nHAP, and significantly
surpassed commercial cyanoacrylate (0.64 MPa). O-BDSG exhibited degradability
with 51% mass loss after 6 months of implantation. In vivo critical defect and tibia fracture models demonstrated the promoted
osteogenesis of the O-BDSG, with a regenerated bone volume of 75%
and mechanical function restoration to 94% of the native tibia after
8 weeks. The glue can be flexibly adapted to clinical scenarios with
a curing time window of about 3 min. This work shows promising prospects
for clinical application in orthopedic surgery and may inspire the
design and development of bone adhesives
Degradable Nanohydroxyapatite-Reinforced Superglue for Rapid Bone Fixation and Promoted Osteogenesis
Bone glue with robust adhesion is
crucial for treating
complicated
bone fractures, but it remains a formidable challenge to develop a
“true” bone glue with high adhesion strength, degradability,
bioactivity, and satisfactory operation time in clinical scenarios.
Herein, inspired by the hydroxyapatite and collagen matrix composition
of natural bone, we constructed a nanohydroxyapatite (nHAP) reinforced
osteogenic backbone-degradable superglue (O-BDSG) by in situ radical ring-opening polymerization. nHAP significantly enhances
adhesive cohesion by synergistically acting as noncovalent connectors
between polymer chains and increasing the molecular weight of the
polymer matrix. Moreover, nHAP endows the glue with bioactivity to
promote osteogenesis. The as-prepared glue presented a 9.79 MPa flexural
adhesion strength for bone, 4.7 times that without nHAP, and significantly
surpassed commercial cyanoacrylate (0.64 MPa). O-BDSG exhibited degradability
with 51% mass loss after 6 months of implantation. In vivo critical defect and tibia fracture models demonstrated the promoted
osteogenesis of the O-BDSG, with a regenerated bone volume of 75%
and mechanical function restoration to 94% of the native tibia after
8 weeks. The glue can be flexibly adapted to clinical scenarios with
a curing time window of about 3 min. This work shows promising prospects
for clinical application in orthopedic surgery and may inspire the
design and development of bone adhesives
Liquid-Infused Poly(styrene‑<i>b</i>‑isobutylene‑<i>b</i>‑styrene) Microfiber Coating Prevents Bacterial Attachment and Thrombosis
Infection
and thrombosis associated with medical implants cause significant
morbidity and mortality worldwide. As we know, current technologies
to prevent infection and thrombosis may cause severe side effects.
To overcome these complications without using antimicrobial and anticoagulant
drugs, we attempt to prepare a liquid-infused poly(styrene-<i>b</i>-isobutylene-<i>b</i>-styrene) (SIBS) microfiber
coating, which can be directly coated onto medical devices. Notably,
the SIBS microfiber was fabricated through solution blow spinning.
Compared to electrospinning, the solution blow spinning method is
faster and less expensive, and it is easy to spray fibers onto different
targets. The lubricating liquids then wick into and strongly adhere
the microfiber coating. These slippery coatings can effectively suppress
blood cell adhesion, reduce hemolysis, and inhibit blood coagulation
in vitro. In addition, <i>Pseudomonas aeruginosa</i> (<i>P. aeruginosa</i>) on the lubricant infused coatings slides
readily, and no visible residue is left after tilting. We furthermore
confirm that the lubricants have no effects on bacterial growth. The
slippery coatings are also not cytotoxic to L929 cells. This liquid-infused
SIBS microfiber coating could reduce the infection and thrombosis
of medical devices, thus benefiting human health
Liquid-Infused Poly(styrene‑<i>b</i>‑isobutylene‑<i>b</i>‑styrene) Microfiber Coating Prevents Bacterial Attachment and Thrombosis
Infection
and thrombosis associated with medical implants cause significant
morbidity and mortality worldwide. As we know, current technologies
to prevent infection and thrombosis may cause severe side effects.
To overcome these complications without using antimicrobial and anticoagulant
drugs, we attempt to prepare a liquid-infused poly(styrene-<i>b</i>-isobutylene-<i>b</i>-styrene) (SIBS) microfiber
coating, which can be directly coated onto medical devices. Notably,
the SIBS microfiber was fabricated through solution blow spinning.
Compared to electrospinning, the solution blow spinning method is
faster and less expensive, and it is easy to spray fibers onto different
targets. The lubricating liquids then wick into and strongly adhere
the microfiber coating. These slippery coatings can effectively suppress
blood cell adhesion, reduce hemolysis, and inhibit blood coagulation
in vitro. In addition, <i>Pseudomonas aeruginosa</i> (<i>P. aeruginosa</i>) on the lubricant infused coatings slides
readily, and no visible residue is left after tilting. We furthermore
confirm that the lubricants have no effects on bacterial growth. The
slippery coatings are also not cytotoxic to L929 cells. This liquid-infused
SIBS microfiber coating could reduce the infection and thrombosis
of medical devices, thus benefiting human health
Nuclease-Functionalized Poly(Styrene‑<i>b</i>‑isobutylene‑<i>b</i>‑styrene) Surface with Anti-Infection and Tissue Integration Bifunctions
Hydrophobic thermoplastic elastomers,
e.g., poly(styrene-<i>b</i>-isobutylene-<i>b</i>-styrene) (SIBS), have found
various in vivo biomedical applications. It has long been recognized
that biomaterials can be adversely affected by bacterial contamination
and clinical infection. However, inhibiting bacterial colonization
while simultaneously preserving or enhancing tissue-cell/material
interactions is a great challenge. Herein, SIBS substrates were functionalized
with nucleases under mild conditions, through polycarboxylate grafts
as intermediate. It was demonstrated that the nuclease-modified SIBS
could effectively prevent bacterial adhesion and biofilm formation.
Cell adhesion assays confirmed that nuclease coatings generally had
no negative effects on L929 cell adhesion, compared with the virgin
SIBS reference. Therefore, the as-reported nuclease coating may present
a promising approach to inhibit bacterial infection, while preserving
tissue-cell integration on polymeric biomaterials
Liquid-Infused Poly(styrene‑<i>b</i>‑isobutylene‑<i>b</i>‑styrene) Microfiber Coating Prevents Bacterial Attachment and Thrombosis
Infection
and thrombosis associated with medical implants cause significant
morbidity and mortality worldwide. As we know, current technologies
to prevent infection and thrombosis may cause severe side effects.
To overcome these complications without using antimicrobial and anticoagulant
drugs, we attempt to prepare a liquid-infused poly(styrene-<i>b</i>-isobutylene-<i>b</i>-styrene) (SIBS) microfiber
coating, which can be directly coated onto medical devices. Notably,
the SIBS microfiber was fabricated through solution blow spinning.
Compared to electrospinning, the solution blow spinning method is
faster and less expensive, and it is easy to spray fibers onto different
targets. The lubricating liquids then wick into and strongly adhere
the microfiber coating. These slippery coatings can effectively suppress
blood cell adhesion, reduce hemolysis, and inhibit blood coagulation
in vitro. In addition, <i>Pseudomonas aeruginosa</i> (<i>P. aeruginosa</i>) on the lubricant infused coatings slides
readily, and no visible residue is left after tilting. We furthermore
confirm that the lubricants have no effects on bacterial growth. The
slippery coatings are also not cytotoxic to L929 cells. This liquid-infused
SIBS microfiber coating could reduce the infection and thrombosis
of medical devices, thus benefiting human health
Fabrication of a Detection Platform with Boronic-Acid-Containing Zwitterionic Polymer Brush
Development of technologies for biomedical
detection platform is critical to meet the global challenges of various
disease diagnoses, especially for point-of-use applications. Because
of its natural simplicity, effectiveness, and easy repeatability,
random covalent-binding technique is widely adopted in antibody immobilization.
However, its antigen-binding capacity is relatively low when compared
to site-specific immobilization of antibody. Herein, we report that
a detection platform modified with boronic acid (BA)-containing sulfobetaine-based
polymer brush. Mainly because of the advantage of oriented immobilization
of antibody endowed with BA-containing three-dimensional polymer brush
architecture, the platform had a high antigen-binding capacity. Notably,
nonspecific protein adsorption was also suppressed by the zwitterionic
pendants, thus greatly enhanced signal-to-noise (S/N) values for antigen
recognition. Furthermore, antibodies captured by BA pendants could
be released in dissociation media. This new platform is promising
for potential applications in immunoassays