Microneedles (MNs) create micropunctures and deliver drugs or nutrients deep into skin layer. We demonstrated that MNs, coated with electrosprayed nanoparticles loaded with functional molecules, are ...useful for transdermal delivery.
Electrospraying was utilised to generate drug-loaded nanoparticles and to create uniform coating on MNs. Process parameters and release kinetics were evaluated in vitro. The in vivo efficacy of insulin-coated MNs was investigated using diabetic rats.
Electrosprayed micro/nanoparticles loaded with dye or insulin were coated on MNs with particle size of 515 ± 286 and 522 ± 261 nm, respectively. Optimally coated MNs resulted in >70% transfer rate into porcine skins. Insulin-coated MNs were applied to diabetic rats resulting in reduction of blood glucose levels fluctuations, compared to subcutaneous injections.
Electrospraying is shown to be an effective method to coat MNs with drug-loaded nanoparticles. Coated MNs provide a promising platform for cosmetic, drug and protein delivery applications.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In this work, a microfabricated anode based on gold coated poly(ϵ‐caprolactone) fiber was developed that outperformed gold microelectrode by a factor of 2.65‐fold and even carbon paper by 1.39‐fold. ...This is a result of its ability to three‐dimensionally interface with bacterial biofilm, the metabolic “engines” of the microbial fuel cell (MFC). We also examined unavoidable issues as the MFC is significantly reduced in size (e.g. to the microscale); (1) bubble production or movement into the microchamber and (2) high sensitivity to flow rate variations. In fact, intentionally induced bubble generation in the anodic chamber reduced the MFC current density by 33% and the MFC required 4 days to recover its initial performance. Under different flow rates in the anode chamber, the current densities were almost constant, however, the current increased up to 38% with increasing flow rate in the cathode.
Using combined excitation emission spectroscopy, we performed a comparative study of europium ions in GaN in samples that have been in situ doped during interrupted growth epitaxy (IGE) or ...conventional molecular beam epitaxy (MBE) as well as samples that were grown using organometallic vapor phase epitaxy (OMVPE) and subsequently ion implanted with Eu ions. Through site-selective resonant excitation, we are able to unambiguously assign all major observed transitions to a combination of different incorporation sites and electron–phonon coupled transitions. We identified at least nine different incorporation sites of Eu ions in GaN and studied how these sites behave under different excitation conditions and how their relative number is modified by different growth and doping conditions. The coupling to phonons has also been studied for a series of Al
x
Ga
1−
x
N samples with
x
=0…1. We find that a main site most resembling an unperturbed Eu ion on Ga site is always dominant, while the minority sites are changing substantially in relative numbers and can occur in some samples fairly close in emission intensity to the main site. In terms of the excitation pathway after the creation of electron-hole pairs, we found three types of centers: (1) sites that are dominantly excited through shallow defect traps; (2) sites that are excited through a deep defect trap; (3) sites that cannot be excited at all including the majority of the main sites. We interpret this finding to indicate that the ion in this environment is not very efficient in trapping excitation and that the indirect excitation involving other traps depends on the ion/trap distance. Many of the main sites are far away from these traps and cannot be excited through this channel at all. The efficiency of excitation is highest for the deep traps, indicating that it would be desirable to enrich the respective site, as has been done with some success in the IGE grown samples.
The cover feature shows the versatility of coaxial electrospinning in forming fibers with complex structures. Polymer solutions are fed into a nozzle with concentric openings from which a coaxial ...liquid jet is extracted by the application of an electric field. The resulting core–sheath fibers with nano/micrometer diameter are formed with a variety of structures and show properties that are useful in many important applications. More details are given in the Review by D. Han and A. Steckl on page 1453 in Issue 10, 2019 (DOI: 10.1002/cplu.201900281).
We report on the use of nucleic acid bases (NBs) in organic light emitting diodes (OLEDs). NBs are small molecules that are the basic building blocks of the larger DNA polymer. NBs readily thermally ...evaporate and integrate well into the vacuum deposited OLED fabrication. Adenine (A) and thymine (T) were deposited as electron-blocking/hole-transport layers (EBL/HTL) that resulted in increases in performance over the reference OLED containing the standard EBL material NPB. A-based OLEDs reached a peak current efficiency and luminance performance of 48 cd/A and 93,000 cd/m(2), respectively, while T-based OLEDs had a maximum of 76 cd/A and 132,000 cd/m(2). By comparison, the reference OLED yielded 37 cd/A and 113,000 cd/m(2). The enhanced performance of T-based devices is attributed to a combination of energy levels and structured surface morphology that causes more efficient and controlled hole current transport to the emitting layer.
The “no reaction” lateral flow assay (nrLFA) uses a simplified LFA structure with no conjugate pad and no stored reagents. In the nrLFA, the capillary-based transport time or distance is the key ...indicator, rather than the outcome of a biochemical reaction. Hence, the calibration and reproducibility of the nrLFA device are critical. The capillary flow properties of several membrane types (nitrocellulose, nylon, cellulose acetate, polyethersulfone, and polyvinylidene difluoride) are evaluated. Flow rate evaluations of MilliporeSigma Hi-Flow™ Plus (HF075, HF135 and HF180) nitrocellulose membranes on nrLFA are performed using bodily fluids (whole blood, blood plasma, and artificial sweat). The results demonstrate that fluids with lower viscosity travel faster, and membranes with slower flow rate exhibit higher capability to distinguish fluids with different viscosities. Reproducibility tests of nrLFA are performed on HF075, demonstrating excellent reproducibility. The coefficient of variation for blood coagulation tests performed with the nrLFA using induced coagulation was 5% for the plasma front and 2% for the RBC front. The effects of variation in blood hematocrit and sample volume are also reported. The overall results indicate that the nrLFA approach has a high potential to be commercially developed as a blood monitoring point-of-care device with simple calibration capability and excellent reproducibility.
Nanofibers consisting of the bulk heterojunction organic photovoltaic (BHJ–OPV) electron donor–electron acceptor pair poly(3‐hexylthiophene):phenyl‐C61‐butyric acid methyl ester (P3HT:PCBM) are ...produced through a coaxial electrospinning process. While P3HT:PCBM blends are not directly electrospinnable, P3HT:PCBM‐containing fibers are produced in a coaxial fashion by utilizing polycaprolactone (PCL) as an electrospinnable sheath material. Pure P3HT:PCBM fibers are easily obtained after electrospinning by selectively removing the PCL sheath with cyclopentanone (average diameter 120 ± 30 nm). These fibers are then incorporated into the active layer of a BHJ–OPV device, which results in improved short‐circuit current densities, fill factors, and power‐conversion efficiencies (PCE) as compared to thin‐film devices of identical chemical composition. The best‐performing fiber‐based devices exhibit a PCE of 4.0%, while the best thin‐film devices have a PCE of 3.2%. This increase in device performance is attributed to the increased in‐plane alignment of P3HT polymer chains on the nanoscale, caused by the electrospun fibers, which leads to increased optical absorption and subsequent exciton generation. This methodology for improving device performance of BHJ–OPVs could also be implemented for other electron donor–electron acceptor systems, as nanofiber formation is largely independent of the PV material.
Nanofibers of poly(3‐hexylthiophene):phenyl‐C61‐butyric acid methyl ester (P3HT:PCBM) are created using coaxial electrospinning and are incorporated into the active layer of bulk heterojunction organic photovoltaic (BHJ–OPV) devices. These devices exhibit improved power‐conversion efficiencies (4.0%) compared to thin‐film devices of identical chemical composition (3.2%).
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