5 research outputs found
Study of the Dynamic Uptake of Free Drug and Nanostructures for Drug Delivery Based on Bioluminescence Measurements
The past two decades have witnessed the great growth of the development of novel drug carriers. However, the releasing dynamics of drug from drug carriers in vivo and the interactions between cells and drug carriers remain unclear. In this paper, liposomes were prepared to encapsulate D-luciferin, which was the substrate of luciferase and served as a model drug. Based on the theoretical calculation of active loading, methods of preparation for liposomes were optimized. Only when D-luciferin was released from liposomes or taken in by the cells could bioluminescence be produced under the catalysis of luciferase. Models of multicellular tumor spheroid (MCTS) were built with 4T1-luc cells that expressed luciferase stably. The kinetic processes of uptake and distribution of free drugs and liposomal drugs were determined with models of cell suspension, monolayer cells, MCTS, and tumor-bearing nude mice. The technology platform has been demonstrated to be effective for the study of the distribution and kinetic profiles of various liposomes as drug delivery systems
Coffee-Ring-Free Quantum Dot Thin Film Using Inkjet Printing from a Mixed-Solvent System on Modified ZnO Transport Layer for Light-Emitting Devices
Inkjet
printing has been considered an available way to achieve
large size full-color RGB quantum dots LED display, and the key point
is to obtain printed film with uniform and flat surface profile. In
this work, mixed solvent of 20 vol % 1,2-dichlorobenzene (oDCB) with
cyclohexylbenzene (CHB) was used to dissolve green quantum dots (QDs)
with CdSe@ZnS/ZnS core/shell structure. Then, by inkjet printing,
a flat dotlike QDs film without the coffee ring was successfully obtained
on polyetherimide (PEI)-modified ZnO layer, and the printed dots array
exhibited great stability and repeatability. Here, adding oDCB into
CHB solutions was used to reduce surface tension, and employing ZnO
nanoparticle layer with PEI-modified was used to increase the surface
free energy. As a result, a small contact angle is formed, which leads
to the enhancement of evaporation rate, and then the coffee ring effect
was suppressed. The printed dots with flat surface profile were eventually
realized. Moreover, inverted green QD-LEDs with PEI-modified ZnO film
as electron transport layer (ETL) and printed green QDs film as emission
layer were successfully fabricated. The QD-LEDs exhibited the maximum
luminance of 12 000 cd/m<sup>2</sup> and the peak current efficiency
of 4.5 cd/A at luminance of 1500 cd/m<sup>2</sup>
Fully Solution-Processed Tandem White Quantum-Dot Light-Emitting Diode with an External Quantum Efficiency Exceeding 25%
Solution-processed
electroluminescent tandem white quantum-dot
light-emitting diodes (TWQLEDs) have the advantages of being low-cost
and high-efficiency and having a wide color gamut combined with color
filters, making this a promising backlight technology for high-resolution
displays. However, TWQLEDs are rarely reported due to the challenge
of designing device structures and the deterioration of film morphology
with component layers that can be deposited from solutions. Here,
we report an interconnecting layer with the optical, electrical, and
mechanical properties required for fully solution-processed TWQLED.
The optimized TWQLEDs exhibit a state-of-the-art current efficiency
as high as 60.4 cd/A and an extremely high external quantum efficiency
of 27.3% at a luminance of 100 000 cd/m<sup>2</sup>. A high
color gamut of 124% NTSC 1931 standard can be achieved when combined
with commercial color filters. These results represent the highest
performance for solution-processed WQLEDs, unlocking the great application
potential of TWQLEDs as backlights for new-generation displays
Highly Efficient All-Solution Processed Inverted Quantum Dots Based Light Emitting Diodes
In
all-solution processed inverted quantum dots based light emitting
diodes (QLEDs), the solvent erosion on the quantum dot (QD) layer
prevents devices from reaching high performance. By employing an orthogonal
solvent 1,4-dioxane for the hole transport layer (HTL) polyÂ(9-vinlycarbazole)
(PVK), the external quantum efficiencies (EQE) of red QLED is increased
4-fold, while the luminous efficiencies (LE) of blue QLED is enhanced
by 25 times, compared to the previous devices’ record. To further
improve the device efficiency and reduce the efficiency roll-off,
solution processed PVK/poly [(9,9-dioctylfluorenyl-2,7-diyl)-<i>co</i>-(4,4′-(<i>N</i>-(<i>p</i>-butylphenyl))Âdiphenylamine)]
(TFB) double-layer HTL is introduced to facilitate hole injection
with stepwise energy level. By reducing the hole injection barrier,
the turn-on voltage of QLEDs decreases from 3.4 to 2.7 V for red,
from 5.1 to 2.7 V for green, and from 5.3 to 4.1 V for blue. The peak
LE reach 22.1 cd/A, 21.4 cd/A, and 1.99 cd/A, while the maximum EQE
reach 12.7%, 5.29%, and 5.99%, for red, green, and blue QLEDs, respectively.
To the best of our knowledge, the red and blue QLEDs exhibit the best
device performance among all the all-solution processed inverted QLEDs.
In addition, the blue QLED is the champion among all the inverted
QLEDs, including the devices fabricated by thermal evaporation