- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Tailoring the collagen film structural properties via direct laser crosslinking of star-shaped polylactide for robust scaffold formation
摘要： Application of restructured collagen-based biomaterials is generally restricted by their poor mechanical properties, which ideally must be close to those of a tissue being repaired. Here, we present an approach to the formation of a robust biomaterial using laser-induced curing of a photosensitive star-shaped polylactide. The created collagen-based structures demonstrated an increase in the Young’s modulus by more than an order of magnitude with introduction of reinforcing patterns (from 0.15±0.02 MPa for the untreated collagen to 51.2±5.6 MPa for the reinforced collagen). It was shown that the geometrical configuration of the created reinforcing pattern affected the scaffold’s mechanical properties only in the case of a relatively high laser radiation power density, when the effect of accumulated thermomechanical stresses in the photocured regions was significant. Photo-crosslinking of polylactide did not compromise the scaffold’s cytotoxicity and provided fluorescent regions in the collagen matrix, that create a potential for noninvasive monitoring of such materials’ biodegradation kinetics in vivo.
关键词： mechanical properties,collagen,reinforcements,photopolymerization,biocompatible polymers,riboflavin
更新于2025-11-21 11:24:58
-
NIR-Fluorescent Multidye Silica Nanoparticles with Large Stokes Shifts for Versatile Biosensing Applications
摘要： We have synthesized and characterized of a series of single and multidye copolymerized nanoparticles with large to very large Stokes shifts (100 to 255 nm) for versatile applications as standalone or multiplexed probes in biological matrices. Nanoparticles were prepared via the St?ber method and covalently copolymerized with various combinations of three dyes, including one novel aminocyanine dye. Covalently encapsulated dyes exhibited no significant leakage from the nanoparticle matrix after more than 200 days of storage in ethanol. Across multiple batches of nanoparticles with varying dye content, the average yields and average radii were found to be highly reproducible. Furthermore, the batch to batch variability in the relative amounts of dye incorporated was small (relative standard deviations <2.3%). Quantum yields of dye copolymerized nanoparticles were increased 50% to 1000% relative to those of their respective dye-silane conjugates, and fluorescence intensities were enhanced by approximately three orders of magnitude. Prepared nanoparticles were surface modified with polyethylene glycol and biotin and bound to streptavidin microspheres as a proof of concept. Under single wavelength excitation, microsphere-bound nanoparticles displayed readily distinguishable fluorescence signals at three different emission wavelengths, indicating their potential applications to multicolor sensing. Furthermore, nanoparticles modified with polyethylene glycol and biotin demonstrated hematoprotective qualities and reduced nonspecific binding of serum proteins, indicating their potential suitability to in vivo imaging applications.
关键词： Fluorescent silica nanoparticles,Biocompatible nanoparticles,Large stokes shift,Near-infrared fluorescence,Multicolor assay,Resonance energy transfer
更新于2025-09-23 15:23:52
-
Biocompatible and sustainable power supply for self-powered wearable and implantable electronics using III-nitride thin-film-based flexible piezoelectric generator
摘要： Energy harvesters that scavenge biomechanical energy are promising power supply candidates for wearable and implantable electronics. Of the most widely used energy harvesters, piezoelectric generators can generate more electric charge than their triboelectric counterparts with similar device size, thus are more suitable to make compact wearable devices. However, most high-power piezoelectric generators are made from lead zirconate titanate, making them undesirable for wearable applications due to the toxic lead element. In this study, a flexible piezoelectric generator (F-PEG) is fabricated with chemically stable and biocompatible Group-III-nitride (III-N) thin film by a layer-transfer method. The III-N thin-film F-PEG can generate an open-circuit voltage of 50 V, a short-circuit current of 15 μA, and a maximum power of 167 μW at a load resistance of 5 M?. Applications of the III-N thin-film F-PEG are demonstrated by directly powering electronics such as light-emitting diodes and electric watches, and by charging commercial capacitors and batteries to operate an optical pulse sensor. Furthermore, the III-N thin-film F-PEG shows good durability and a stable output after being subjected to severe buckling tests of over 30,000 cycles.
关键词： flexible,piezoelectric generators,thin film,III-nitride,self-powered system,biocompatible
更新于2025-09-23 15:23:52
-
Synthesis and characterization of nickel free titanium–hydroxyapatite composite coating over Nitinol surface through in-situ laser cladding and alloying
摘要： In this study, a high power fibre laser was used to synthesize titanium hydroxyapatite composite coating over biomedical-grade Nitinol surface through laser in-situ formation, cladding and alloying processes. The laser fluence is varied in the range of 2 kJ/cm2 to 8 kJ/cm2 in view of establishing a relationship between various in-situ phase-formation characteristics along with the rate of diffusion of the base material in the cladding zone with molten pool temperature. The alloying with base Nitinol material and subsequent diffusion of titanium to the in-situ formed calcium phosphate cladding layer are observed in the samples treated with laser fluence of 4 kJ/cm2 or above. Double layer configuration of the solidified molten pool is mostly found in all the cladding samples. At the fluence of 6 kJ/cm2 or above, the top layer primarily comprises segregated titanium-hydroxyapatite phase along with diffusion of titanium from the base material. Whereas, the bottom part of the molten pool is dominated with titanium-rich nickel–titanium intermetallic reinforced with nano particles. The steady-state variations of calcium and elemental presence of titanium through the cladding cross-section along with no nickel or oxide presence are confirmed through EDS line scans. The spherical and lamellar structures of formation of titanium-hydroxyapatite on the top surface also help to improve the overall corrosion resistance properties as compared to the bare surface. The modulus of elasticity is controlled by the variation of the top layer and intermediate layer composition and thickness, which varies with laser fluence. It falls in the range of 6–30 GPa which is similar to natural bone. Thus this nickel-free alloying and cladding layer of titanium-hydroxyapatite can serve as one of the potential candidates for use as a coating over the load bearing Nitinol implants to arrest the nickel release phenomena.
关键词： Titanium–calcium coating,Biocompatible functional coating,Hydroxyapatite,Nitinol surface modification,Laser cladding and alloying
更新于2025-09-23 15:22:29
-
Cancer Selective Turn-on Fluorescence Imaging Using a Biopolymeric Nanocarrier
摘要： Most nanoparticle-based bioresearch for clinical applications is unable to overcome the clinical barriers of efficacy (e.g., sensitivity and selectivity), safety for human use, and mass-production processes. Here, we proposed a promising concept of using a biocompatible nanocarrier that delivers natural fluorescent precursors into cancerous cells. The nanocarrier is a biopolymeric nanoparticle that can be easily loaded with fluorescent precursors to form a fluorescent moiety via a biosynthesis pathway. Once delivered into cancerous cells, the nanocarriers are selectively turned on and distinctively fluoresce upon excitation. We, therefore, demonstrated the efficacy of the selective turn-on fluorescence of the nanocarriers in in vitro co-culture models and in vivo tumor-bearing models.
关键词： Hyaluronic Acid,Cancer Diagnosis,Biocompatible Nanocarrier,Turn-on Fluorescence,5-Aminolevulinic Acid
更新于2025-09-23 15:22:29
-
Synthesis of Chiral Gold Nanoparticle by Direct Reduction with L and D-Serine and Enhanced Anti-Mycobacterial Activity by D-Serine Protected Gold Nanoparticle
摘要： Current situation demands more biocompatible and non-toxic nanostructures. Towards this the present study describes the synthesis of gold nanoparticle by direct reduction of tetrachloroauric acid with both D- and L-enantiomeric forms of the amino acid serine. The formation of nanoparticle was confirmed by examining different physical characteristics like surface plasmon resonance. Moreover, the retention of chirality of the reduced particle was also evident from circular dichroism spectroscopy experiment. In addition, the shielding of the nanoparticle by respective amino acid was confirmed by Scanning Electron Microscope and Energy Dispersive X-ray Analysis (SEM-EDAX). As D-serine is known to be active against Mycobacteria, examination of the biological activity of the D-serine protected particle was performed against the same. The result showed higher inhibitory activity of the particle against Mycobacterium smegmatis than D-serine alone. Thus the present study describes a new protocol for the synthesis of chiral gold nanoparticle that can be beneficial in enantioselective biological applications.
关键词： Chiral nanoparticle,D-serine,Mycobacteria,Biocompatible gold nanoparticle,L-serine
更新于2025-09-23 15:22:29
-
Mercaptoalkanoic Acida??Induced Band Gap Attenuation of Copper Selenide Quantum Dot
摘要： Copper selenide quantum dot (CuSeQD) materials functionalised with mercaptoalkanoic acids {3-mercaptopropionic acid (3-MPA), 6-mercaptohexanoic acid (6-MHA) and mercaptosuccinic acid (MSA)} were synthesized by a reproducible aqueous colloidal technique at room temperature. The impact of the capping agents on the size and the crystallinity of the CuSeQD materials, were investigated by small angle X-ray scattering (SAXS) and X-ray diffraction (XRD) spectroscopic techniques, respectively. SAXS results confirmed that 6-MHA-CuSeQD had the smallest average particle core size when dried, whereas MSA-CuSeQD had the smallest size in aqueous solution, though with a tendency to aggregate. Dynamic light scattering (DLS) measurements indicated strong bonding of the capping agents to CuSe particles, with MSA being the weakest binding agent, confirmed by low Zeta potential(ζ = (cid:0) 31.1 mV) and high polydispersity index (0.469) values. UV-Vis absorption studies confirmed a large blue shift of the band gap for the QD compared to the bulk material, with characteristic absorption band (λ) and direct band gap (Egd) values being (λ = 435 nm, Egd = 5.6 eV) and (λ = 400 nm, Egd = 8.0 eV), (λ = 340 nm, Egd = 4.0 eV), for 6-MHA-CuSeQD, 3-MPA-CuSeQD and MSA-CuSeQD, respectively. As supported by the formal potential values for 6-MHA-CuSeQD (E0’ ? 120 mV), 3-MPA-CuSeQD (E0’ ? 159 mV) and MSA-CuSeQD (E0’ ? 183 mV), the smaller the particle size, the lower the potential required for the application of the quantum dots in an electron transfer process.
关键词： Cyclic Voltammetry,biocompatible,copper selenide,Aqueous synthesis,quantum dots
更新于2025-09-23 15:21:01
-
Biocompatible microlasers based on polyvinyl alcohol microspheres
摘要： Biocompatible microlasers, generally made of bio-derived materials, are promising for biosensing and cell-tracking. These kinds of lasers offer favourable opportunities like biocompatibility and biodegradability but the materials used often require complicated synthesis and high cost. In this work, we demonstrate that polyvinyl alcohol (PVA), a synthetic water-soluble low-cost polymer, with fascinating properties such as good transparency, biocompatibility, biodegradability is an excellent candidate for making laser cavity. Using a simple and effective technique, dye-doped PVA microspheres can be fabricated with various sizes from 10 to 200 μm. These microspheres can act as excellent lasers under optical excitation with a lasing threshold of ~2 μJ/mm2 and Q factor of lasing modes of ~3000. The lasing mechanism is studied and it is ascribed to WGM. Size-dependent lasing characteristics including lasing spectrum, Q factor and lasing threshold are investigated. Owing to the ease of fabrication, the cost-effectiveness, the biocompatibility of the PVA material, our biocompatible microlasers are promising for future biosensing applications.
关键词： Whispering gallery mode,Microlaser,Polyvinyl alcohol,Biocompatible
更新于2025-09-16 10:30:52
-
Resonance energy transfer-assisted random lasing in light-harvesting bio-antenna enhanced with a plasmonic local field
摘要： Thanks to the advent of the random laser, new light applications have opened up, ranging from biophotonic to security devices. Here, by using the well-known but unexplored light-harvesting bio-pigment of butterfly pea (Clitoria ternatea, CT) flower extract, generation of continuous-wave (CW) random lasing at ~660 nm has been demonstrated. Furthermore, a wavelength tunability of ~30 nm in the lasing emission was obtained by utilizing the resonance energy transfer (RET) mechanism in a gain medium with a binary mixture of CT extract and a commercially available methylene blue (MB) dye as the gain medium. In the CT extract–dye mixture, the bio-pigments are acting as donors and the MB dye molecules are acting as acceptors. Amplification in intensity of the lasing emission of this binary system has further been achieved in the presence of optimized concentrations of metal (Ag)–semiconductor (ZnO) scattering nanoparticles. Interestingly, the lasing threshold has been reduced from 128 to 25 W cm?2, with a narrowed emission peak just after loading of the Ag nanoplasmon in the ZnO-doped binary gain medium. Thanks to the strong localized electric field in the metal nanoplasmon, and the multiple scattering effects of ZnO, the lasing threshold was reduced by approximately four times compared to that of the gain medium without the use of scatterers. Thus, we believe that our findings on wavelength-tunable, non-toxic, biocompatible random lasing will open up new applications, including the design of low-cost biophotonic devices.
关键词： light-harvesting bio-antenna,resonance energy transfer,random laser,plasmonic local field,biocompatible
更新于2025-09-16 10:30:52
-
Gold nanoroda??loaded (PLGA-PEG) nanocapsules as near-infrared controlled release model of anticancer therapeutics
摘要： Despite of high in vitro anticancer efficacy of many chemotherapeutics, their in vivo use is limited due to lack of biocompatibility and tumor targeting. Near-infrared (NIR) photothermally induced phase transition of PLGA-PEG regime was utilized for developing highly efficient photoresponsive drug delivery systems. Co-encapsulation of plasmonic gold nanorods (GNRs), as NIR-trigger, with the novel and highly efficient anticancer drug N′-(2-Methoxybenzylidene)-3-methyl-1-phenyl-H-Thieno[2,3-c]Pyrazole-5-Carbohyd-razide (MTPC) produced NIR-responsive biodegradable polymeric (PLGA-b-PEG) nanocapsules. This remotely controllable drug release significantly enhanced both biodistribution and pharmacokinetics of the hydrophobic drug. Intravenous (IV) injection of the prepared nanocapsules (MTPC/GNRs@PLGA-PEG) to tumor-bearing mice followed by extracorporeal exposure of the tumor to NIR light resulted in highly selective drug accumulation at the tumor sites. In vivo biodistribution and pharmacokinetics utilizing iodine-131 drug-radiolabelling technique revealed a maximum target to non-target ratio (T/NT) of 5.8, 4 h post-injection with maximum drug level in the tumor (6.3 ± 0.6% of the injected dose).
关键词： Pharmacokinetics,Biocompatible polymers,Radiolabelling,NIR-responsive nanocapsules,Biodistribution
更新于2025-09-16 10:30:52