Cyclodextrins as eminent constituents in nanoarchitectonics for drug delivery systems

• Makoto Komiyama

Beilstein J. Nanotechnol. 2023, 14, 218–232, doi:10.3762/bjnano.14.21

• very stiff. Upon photoirradiation, however, the crosslinkings for the gel formation are broken almost completely, releasing the encapsulated drugs (e.g., DOX as anticancer drug). 2.3 Upconversion nanoparticles to release drugs by near-infrared light As an external stimulus for DDSs, near-infrared (NIR

• the use of upconversion nanoparticles to convert NIR to shorter-wavelength light for photoreactions. These nanoparticles usually contain rare-earth metal ions, which have long-living excited states. Thus, they achieve sequential energy absorption and convert two or more low-energy (NIR) photons into

• UV or visible light [54]. In a pioneering work [55], α- and β-CyDs were bound to the surface of upconversion nanoparticles and either azobenzene or arylazopyrazole was added to form inclusion complexes. NIR irradiation (980 nm) was converted to shorter-wavelength light, which isomerized azobenzene or

Effect of different silica coatings on the toxicity of upconversion nanoparticles on RAW 264.7 macrophage cells

• Cynthia Kembuan,
• Helena Oliveira and
• Christina Graf

Beilstein J. Nanotechnol. 2021, 12, 35–48, doi:10.3762/bjnano.12.3

• of Applied Sciences, Fachbereich Chemie- und Biotechnologie, Stephanstr. 7, D-64295 Darmstadt, Germany 10.3762/bjnano.12.3 Abstract Upconversion nanoparticles (UCNPs), consisting of NaYF4 doped with 18% Yb and 2% Er, were coated with microporous silica shells with thickness values of 7 ± 2 and 21

• : cytotoxicity; ion release; RAW 264.7 macrophage cell line; silica coating; upconversion nanoparticles; Introduction Upconversion nanoparticles (UCNPs) convert excitation radiation with long wavelengths to a short-wavelength emission. Since biological molecules do not have an upconversion mechanism, imaging

• flow cytometry through the measurement of side-scattered light, which is proportional to changes in cell granularity or to the internal complexity. Results and Discussion Preparation and characterization of upconversion nanoparticles Oleate-functionalized NaYF4:Yb,Er nanocrystals were prepared by a

Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness

• Cynthia Kembuan,
• Maysoon Saleh,
• Bastian Rühle,
• Ute Resch-Genger and
• Christina Graf

Beilstein J. Nanotechnol. 2019, 10, 2410–2421, doi:10.3762/bjnano.10.231

• + upconversion nanoparticles (UCNP) is presented. The concept enables the precise adjustment of shell thicknesses for the preparation of thick-shelled nanoparticles for applications in plasmonics and sensing. First, an initial 5–11 nm thick shell is grown onto the UCNPs in a reverse microemulsion. This is

• -core particles are obtained. This strategy can be easily transferred to other nanomaterials for the design of plasmonic nanoconstructs and sensor systems. Keywords: reverse microemulsion; silica coating; stepwise growth; thick shells; upconversion nanoparticles; Introduction Lanthanide-based

• nanocrystals have gained importance as inorganic optical reporters in recent years [1][2][3]. The doping of inorganic host NaYF4 matrices with different optically active lanthanide ions can result in so-called upconversion nanoparticles (UCNP) which can absorb photons of lower energy (e.g., near-infrared (NIR

Janus-micromotor-based on–off luminescence sensor for active TNT detection

• Ye Yuan,
• Changyong Gao,
• Daolin Wang,
• Chang Zhou,
• Baohua Zhu and
• Qiang He

Beilstein J. Nanotechnol. 2019, 10, 1324–1331, doi:10.3762/bjnano.10.131

• Beijing Chemical Works, China. All commercial materials were used without further purification. Preparation of Janus UCNP capsule motors NaYF4:Yb/Er upconversion nanoparticles were firstly fabricated using a previously published method [42]. The obtained UCNPs (100 mg) were then mixed with PAA (300 mg) in

Silica-coated upconversion lanthanide nanoparticles: The effect of crystal design on morphology, structure and optical properties

• Uliana Kostiv,
• Miroslav Šlouf,
• Hana Macková,
• Alexander Zhigunov,
• Hana Engstová,
• Katarína Smolková,
• Petr Ježek and
• Daniel Horák

Beilstein J. Nanotechnol. 2015, 6, 2290–2299, doi:10.3762/bjnano.6.235

• widespread applications as drug delivery systems in the diagnosis and treatment of various diseases [1][2]. Recently, upconversion nanoparticles have shown promise as optical materials [3] and a number of reviews [4][5][6] have described their applications in drug and gene delivery [7], cell labeling and

• tracking [8], bioimaging [9] and photodynamic therapy [10]. Lanthanide-doped upconversion nanoparticles emit visible light upon excitation by near-IR light (NIR). Compared with organic dyes and semiconductor quantum dots, upconversion nanoparticles have attractive chemical and optical properties, as well

• obtained from Lachema (Brno, Czech Republic). Ultrapure Q-water ultrafiltered on a Milli-Q Gradient A10 system (Millipore, Molsheim, France) was employed in all experiments. Synthesis of OM-stabilized upconversion nanoparticles Synthesis of the upconversion nanoparticles was similar to a previously

Influence of surface-modified maghemite nanoparticles on in vitro survival of human stem cells

• Michal Babič,
• Daniel Horák,
• Lyubov L. Lukash,
• Tetiana A. Ruban,
• Yurii N. Kolomiets,
• Svitlana P. Shpylova and
• Oksana A. Grypych

Beilstein J. Nanotechnol. 2014, 5, 1732–1737, doi:10.3762/bjnano.5.183

• for the above mentioned purposes [9]. Monosized iron oxide nanoparticles, sometimes called ultra-small superparamagnetic iron oxide nanoparticles, play the dominant role. Quantum dots, gold and, recently, also upconversion nanoparticles are used less frequently. The main advantages of iron oxides