- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Photopolymerization of acrylates by enzymatically synthesized PCL based macrophotoinitiator
摘要： Polycaprolactone based macrophotoinitiator was synthesized via enzymatic ring-opening polymerization by using commercially available Irgacure-2959 as the nucleophilic initiator and Novozyme-435 as the immobilized lipase catalyst. The macrophotoinitiator was further utilized to photopolymerize benzyl acrylate (BzA), tetrahydrofurfurly acrylate (THFA), 2-hydroxyethyl acrylate (HEA) and poly (ethylene glycol) methyl ether acrylate (Mn ~ 480 g/mole) (PEGMEA-480) under Ar atmosphere. The obtained polymers were characterized by 1H Nuclear Magnetic Resonance, Fourier Transform Infrared Spectroscopy, Differential Scanning Calorimetry and Size Exclusion Chromatography. The highest dry polymer conversions were achieved with BzA and THFA. However, due to the gel formation during the photopolymerization reactions of HEA and PEGMEA-480, the dry polymer conversions were comparably lower. The photopolymerization product of BzA demonstrated a single glass transition temperature at –6.5 °C. The enzymatically synthesized macrophotoinitiator was shown to be an efficient catalyst for light-induced polymerization of the abovementioned monomers.
关键词： polycaprolactone,photopolymerization,biocomposites,enzymatic polymerization,macrophotoinitiator,biopolymers
更新于2025-09-23 15:21:01
-
Drug-releasing Biopolymeric Structures Manufactured via Stereolithography
摘要： Additive manufacturing (AM) techniques, such as stereolithography (SLA), enable the preparation of designed complex structures. AM has gained interest especially in the tissue engineering field due to the possibility to manufacture patient specific implants. However, AM could be useful also in controlled drug release applications, since the size and shape of the device, pore architecture and surface to volume ratio can be accurately designed. In this study, SLA was used to prepare polycaprolactone scaffold structures containing the model drug lidocaine. The release of lidocaine was studied and the influence of porosity and surface to volume ratio of structures to the drug release was analyzed. Porous samples released lidocaine faster compared to solid ones, whereas the degree of porosity and surface to volume ratio did not have a clear effect on the drug release profile.
关键词： drug delivery,stereolithography,additive manufacturing,drug release,lidocaine,scaffold,controlled release,polycaprolactone
更新于2025-09-23 15:21:01
-
Synthesis of electrospun nanofibrous structures with controlled optical and electrical properties
摘要： In this study, the optical and electrical influences of 2D graphene flakes in electrospun polycaprolactone (PCL) fibers were observed. Graphene nanoplatelets were added in different concentrations into the PCL solution, and then, using the electrospinning technique, fibers were built from that solution. Three samples were prepared with different graphene concentrations of 0% w/w, 0.5% w/w, and 2.0% w/w. From all three samples, fibers were prepared and tests were conducted for the identification of the properties of fibers. An optical spectroscopy test was performed to identify the optical behavior of the fibers. Scanning electron microscopy tests were conducted for the morphological characterization of the fibers. For the comparison of the electrical conductivity of the three samples, electrical tests were also conducted. In addition, Raman spectroscopy was conducted to characterize the graphene and PCL. This study shows that using graphene can change the properties of fibers, for example, as the graphene content increases, the fiber diameter also increases. Also, by varying the 2D graphene concentration, both electrical and optical properties can be tuned; this can be utilized in the synthesis of nanosensing surfaces and structures.
关键词： polycaprolactone,graphene nanoplatelets,optical properties,electrical properties,electrospun nanofibrous structures
更新于2025-09-23 15:19:57
-
An electrospun polymer composite with fullerene-multiwalled carbon nanotube exohedral complexes can act as memory device
摘要： Functional polymer nanocomposites with distinctive electrical properties made of nanocarbon structures and biodegradable polymers are promising materials for the development of flexible and eco-friendly smart systems. In this work, a novel electrospun conductive polymer nanocomposite made of polycaprolactone with an exohedral complex made of multiwalled carbon nanotubes and fullerene C60 was prepared and characterized. The preparation was straightforward and the complexes self-assembled within the nanocomposite fibers. The nanocomposite showed electrical switching behavior due to charge accumulation of fullerene C60 upon electrical stimulation. Write-once read-many memory devices were fabricated by electrospinning a nanocomposite with 0.8%wt. fullerene C60 onto interdigitated coplanar electrodes. The device retained the ON state for more than 60 days and could be thermally reset, reprogrammed and erased with subsequent electrical and thermal cycling. Moreover, the electrical resistance of the device could be modulated by applying different programming voltage amplitudes and programming times, which revealed its adaptive behavior and potential application to neuromorphic systems.
关键词： Polycaprolactone,Memristor,Conductive nanocomposite
更新于2025-09-23 15:19:57
-
Optimization of Laser Sintering for Demineralized Bone/Polycaprolactone Composite Powder for Bone Tissue Scaffold
摘要： Demineralized bone matrix (DBM) is an excellent bone scaffold material, but is available in only limited sizes. An additive manufacturing (AM) method that retains these properties while enabling customized geometry fabrication would provide bone scaffolds for a larger range of geometries while maintaining the benefits of DBM. This work examines laser sintering (LS) of a blend of demineralized bone matrix (DBM) and polycaprolactone (PCL) using a CO2 laser beam. A comprehensive experimental study was carried out to find the conditions that form defect-free layers while still retaining the favorable biological features of DBM. The results identify a process setting window over which LS can be utilized to constructing complex patient-specific scaffolds. With the identified setting, first, the DBM/PCL blend was fused in the LS machine. Parts were then were further strengthened through a post-processing heat treatment. The shrinkage level, skeletal density, mechanical testing, and porosimetry of the resultant samples were compared to traditional machined DBM blocks. The maximum tensile strength of the samples and post-processing shrinkage depends on heat treatment duration. The tensile strength measurements demonstrate that the post-processing conditions can be tuned to achieve the tensile strength of the demineralized bone strips. Evaluation of the dimensional change suggests that the shrinkage along the laser paths is ~0.3% while thickness shrinks the most (up to ~20%). The porosimetry and density studies showed that the final part achieved over 40% porosity with a density comparable to blocks of DBM.
关键词： laser sintering,porosity,tensile strength,optimization,demineralized bone matrix,shrinkage,additive manufacturing,polycaprolactone
更新于2025-09-19 17:13:59
-
Laser Ablation - From Fundamentals to Applications || Matrix-Assisted Pulsed Laser Evaporation of Organic Thin Films: Applications in Biology and Chemical Sensors
摘要： Polymer and biomolecule processing for medical and electronics applications, i.e. the fabrication of sensors and biosensors, microarrays, or lab on chip devices is a cornerstone field which shows great promise. Laser based thin film deposition techniques such as pulsed laser deposition or matrix-assisted pulsed laser evaporation (MAPLE) are competing with conventional methods for integrating new materials with tailored properties for novel technological developments. Successful polymer and protein thin film deposition requires several key elements for depositing viable and functional thin films, i.e. the characteristics of the laser depositing system, the choice of targets and receiver substrates, etc. This chapter reviews the following topics: brief presentation of the MAPLE process including several examples of polymer materials deposited by MAPLE, thus illustrating the potential of the technique as a gentle laser-assisted deposition method. In particular, the “synthesis” of new materials, their analysis and correlation of the bulk and interface properties to its bio-environment shall be discussed as a method to tackle some bioengineering issues. We will also focus on recent breakthroughs of the MAPLE technique for the fabrication of functional devices, i.e. sensor devices based either on chemoresponsive polymers or on proteins.
关键词： saw,maple,hydroxyapatite nanoparticles,odorant-binding proteins,PEG-PCL-me,polyethylenimine,polyepichlorohydrin,ha,polyethylene glycol-co-polycaprolactone methyl ether,polyisobutylene,lactoferrin
更新于2025-09-19 17:13:59
-
Near-Infrared, Light-Triggered, On-Demand Anti-inflammatories and Antibiotics Release by Graphene Oxide/Elecrospun PCL Patch for Wound Healing
摘要： Very recently, significant attention has been focused on the adsorption and cell adhesion properties of graphene oxide (GO), because it is expected to allow high drug loading and controlled drug release, as well as the promotion of cell adhesion and proliferation. This is particularly interesting in the promotion of wound healing, where antibiotics and anti-inflammatories should be locally released for a prolonged time to allow fibroblast proliferation. Here, we designed an implantable patch consisting of poly(caprolactone) electrospun covered with GO, henceforth named GO–PCL, endowed with high ibuprofen (5.85 mg cm?2) loading, used as anti-inflammatory and antibiotic models respectively, and capable of responding to near infrared (NIR)-light stimuli in order to promptly release the payload on-demand beyond three days. Furthermore, we demonstrated the GO is able to promote fibroblast adhesion, a key characteristic to potentially provide wound healing in vivo.
关键词： polycaprolactone,plasma,wound healing,graphene oxide,vancomycin,on-demand drug release
更新于2025-09-19 17:13:59
-
Laser-triggered shape memory based on thermoplastic and thermoset matrices with silver nanoparticles
摘要： Stimuli responsive shape memory polymers (SMPs) are challenging theme as the materials not only shows the shape changing under the traditional thermal treatment but also under other external stimuli. The present work proposes an in-situ ring opening polymerization (ROP) to combine the thermoset hard segment, i.e. polybenzoxazine, and thermoplastic soft segment, i.e. polycaprolactone and silver nanoparticles (AgNPs) as the laser-trigger. The melamine-based benzoxazine (mBz) plays its important role in allowing the ROP to create the thermoset polybenzoxazine network (PmBz) as well as providing many hydroxyl groups to further conjugation with thermoplastic polycaprolactone matrices (PCL). The AgNPs are the good alternative to select based on their function to be expressed by the very low energy (violet laser at 408 nm, 780 mW) and the surface modifiable with disulfide polycaprolactone (SS-PCL) hybridization for the highly miscible and readily dispersible in PCL matrices. The present work, for the first time, proposes light-triggered SMPs via simple molecular design and synthesis based on an in-situ ROP to combine PmBz thermoset networks and PCL thermoplastic matrices with the AgNPs-PCL to provide the light-thermal responsive function.
关键词： Light-thermal responsive,Silver nanoparticle,Benzoxazine,Polycaprolactone,Light-triggered shape memory polymer
更新于2025-09-11 14:15:04
-
Electrospinning 3D Nanofiber Structure of Polycaprolactone Incorporated with Silver Nanoparticles
摘要： This study presents a one-station 3D fabrication technique of nano?brous scaffold for tissue engineering. A divergence static electric ?eld was introduced in an electrospinning system to induce a self-assembly of aligned polycaprolactone (PCL) nano?bers into a tunable 3D architecture with thickness ranging from 2 to 12 mm. Silver nanoparticles were incorporated into the PCL solution to alter the electrical conductivity. Human ?broblast cells were cultured on the pure PCL nano?ber scaffolds in vitro for 7 days. It was found that the occurrence of nano?ber bridging phenomenon depended on the solution viscosity. The minimum viscosity to form a 3D nano?ber structure was higher than that to form a 2D nano?ber mat. The homogeneity of nano?ber distribution within the 3D space was positively correlated with the electrical conductivity and the weight of the nano?bers. In the cell culture test, ?broblasts proliferated on the scaffold and organized as an aligned matrix which mimicked the microstructure of native musculoskeletal tissues.
关键词： Tissue engineering,3D nano?ber structure,Electrospinning,Polycaprolactone,Silver nanoparticles
更新于2025-09-10 09:29:36
-
Study of Physical and Degradation Properties of 3D-Printed Biodegradable, Photocurable Copolymers, PGSA-co-PEGDA and PGSA-co-PCLDA
摘要： As acrylated polymers become more widely used in additive manufacturing, their potential applications toward biomedicine also raise the demand for biodegradable, photocurable polymeric materials. Polycaprolactone diacrylate (PCLDA) and poly(ethylene glycol) diacrylate (PEGDA) are two popular choices of materials for stereolithography (SLA) and digital light processing additive manufacturing (DLP-AM), and have been applied to many biomedical related research. However, both materials are known to degrade at a relatively low rate in vivo, limiting their applications in biomedical engineering. In this work, biodegradable, photocurable copolymers are introduced by copolymerizing PCLDA and/or PEGDA with poly(glycerol sebacate) acrylate (PGSA) to form a network polymer. Two main factors are discussed: the effect of degree of acrylation in PGSA and the weight ratio between the prepolymers toward the mechanical and degradation properties. It is found that by blending prepolymers with various degree of acrylation and at various weight ratios, the viscosity of the prepolymers remains stable, and are even more 3D printable than pure substances. The formation of various copolymers yielded a database with selectable Young’s moduli between 0.67–10.54 MPa, and the overall degradation rate was significantly higher than pure substance. In addition, it is shown that copolymers fabricated by DLP-AM fabrication presents higher mechanical strength than those fabricated via direct UV exposure. With the tunable mechanical and degradation properties, the photocurable, biodegradable copolymers are expected to enable a wider application of additive manufacturing toward tissue engineering.
关键词： additive manufacturing,poly(glycerol sebacate) acrylate,photocurable polymer,poly(ethylene glycol) diacrylate,digital light processing,polycaprolactone diacrylate,biodegradable polymer
更新于2025-09-09 09:28:46