Oleksandr Selyshchev

Magnetic nanoparticles (MNPs) have emerged as a promising tool for cancer therapy, providing significant potential for multimodal cancer treatments that include chemotherapy, magnetic hyperthermia, and bioactive targeting. The physicochemical properties of MNPs, including size, surface chemistry, and magnetic properties, play a crucial role in determining their therapeutic effectiveness and overall performance in multimodal cancer therapy. The present study introduces a magnetic nanoformulation ( c MNP‐mPEG‐Dox‐Ab) nanobioengineered for an integrated therapeutic approach. The cubic‐shaped MNPs ( c MNP) are functionalized with a biocompatible polymer, mPEG‐NH ₂ , to immobilize anti‐HER2 antibody and the anticancer drug doxorubicin. The nanoformulation exhibits a controlled drug release in response to pH and temperature stimuli. Notably, under an alternating magnetic field (AMF), 64% drug release is observed at an acidic pH, which mimics the tumor microenvironment. Cytotoxicity studies on the HCC1954 breast cancer cells reveal that the nanoformulation without an anti‐HER2 antibody induces 25% cell death, which increases to 52% upon conjugation with the anti‐HER2 antibody, confirming the bioactive targeting effect. Apoptosis studies demonstrate a significant increase in the apoptotic cell population under hyperthermic conditions relative to the physiological temperature. This study underscores the potential of c MNP‐mPEG‐Dox‐Ab nanoformulation to enhance the precision and therapeutic efficacy of multimodal cancer therapy through bioactive targeting.

FluidFM deposition, also known as pressure‐controlled and force‐controlled micropipetting, of nanomaterials suspended in fluidic carrier liquids is known as a capillary‐driven, high‐precision liquid‐in‐liquid deposition and manipulation technique in biofluidic environments. In this work, we report on its usage as a liquid‐on‐solid structuring technique from an aqueous dispersion of colloidal inorganic semiconductor Ag–In–S quantum dots (QDs) stabilized with glutathione ligands on solid substrates. We show the recurrent deposition (3 3 matrix) and characterization of three‐dimensional liquid‐in‐air deposits formed by structured sedimentation of the QDs on gold‐coated glass substrates upon FluidFM deposition via bottom‐up self‐assembly. As critical facts for a successful deposition of the QDs turn out: The aqueous nature of the dispersion, the possibility for its careful adjustment regarding density and composition, and an effective surface energy engineering of both the FluidFM cantilever and the gold‐coated glass substrates mediated by chemical vapor deposition and physical vapor deposition, respectively. This way, the minimal lateral dimensions of the obtained deposits were (500 40) µm, with evaporation‐limited contact‐line widths of (2.0 0.5) µm.

Research in cancer therapies is rapidly advancing and demands the exploration of innovative approaches to further improve the efficacy of treatment. Here a multimodal approach for cancer therapy is reported which combines bioactive targeting, magnetic hyperthermia, and controlled drug release. For this, a nanoformulation MNP‐Chi‐Dox‐Ab, is bioengineered by conjugating CA 15‐3 antibodies to doxorubicin‐loaded functionalized magnetic nanoparticles (MNPs). Solvothermally synthesized MNPs of uniform spherical shape and size are functionalized with thermo‐pH‐responsive chitosan. The nanoformulation showed higher drug release of ≈65% at pH 5 and 42 °C temperature compared to the release at physiological pH and temperature. Furthermore, in an alternating magnetic field drug release is enhanced to 74%. Cytotoxicity studies in MCF‐7 breast cancer cells confirm the active targeting potential of the nanoformulation. For the nanoformulation without bioactive molecule (anti‐CA 15‐3) only 18% cancer cell death is noted whereas with the conjugation of anti‐CA 15‐3, 43% cell death is recorded. Flow cytometry studies revealed an increased apoptotic population at hyperthermic temperature (42 °C) compared to the physiological temperature. These results suggest that MNP‐Chi‐Dox‐Ab nanoformulation represents a promising multimodal platform for synergistic breast cancer therapy by combining active targeting, controlled drug release, and hyperthermia.

Element substitution in Cu ₂ ZnSnS ₄ ‐like chalcogenides offers the potential to create alternative low‐cost photovoltaic and thermoelectric materials with tunable properties. In this work, the “green” synthesis of colloidal cation‐substituted Cu–Ni–Sn–S nanocrystals (CNTS NCs) in aqueous solutions using thioglycolic acid as a stabilizer is reported for the first time. The structural and optical properties of CNTS NCs are studied in colloidal solutions and thin films, and are compared with those of Cu–Zn–Sn–S (CZTS) NCs obtained under similar conditions. The NC sizes of both compounds are estimated to be in the range of 1.5–2.5 nm. Both NCs exhibit strongly non‐stoichiometric composition and a structure corresponding to cationically disordered kesterite Cu ₂ ZnSnS ₄ , which are common features of such quaternary metal‐based chalcogenides. The phonon Raman spectra of CNTS and CZTS NCs exhibit very similar lineshapes, but the CNTS phonon band has a larger width and lower frequency, presumably due to stronger cation disorder. The absorption of both types of NCs extends continuously through the visible range with an estimated bandgap of ≈2.2 eV and sub‐bandgap absorption due to an Urbach tail. The absorption coefficient of CNTS is determined to be α > 10 ² cm ⁻¹ at 700 nm and α > 10 ⁴ cm ⁻¹ at 400 nm.

Magnetic monolayers show great promise for future applications in nanoelectronics, data storage, and sensing. The research in magnetic two‐dimensional (2D) materials focuses on synthetic iodides and tellurides, which suffer from a lack of ambient stability. So far, naturally occurring layered magnetic materials have been overlooked. These minerals offer a unique opportunity to explore complex air‐stable layered systems with high concentration of magnetic ions. Magnetic ordering in iron‐rich phyllosilicates is demonstrated, focusing on minnesotaite, annite, and biotite. These naturally occurring layered materials integrate local moment baring ions of iron via magnesium/aluminum substitution in their octahedral sites. Self‐inherent capping by silicate/aluminate tetrahedral groups enables air stability of ultra‐thin layers. Their structure and iron oxidation states are determined via Raman and X‐ray spectroscopies. Superconducting quantum interference device magnetometry measurements are performed to examine the magnetic ordering. Paramagnetic or superparamagnetic characteristics at room temperature are observed. Below 40 K ferrimagnetic or antiferromagnetic ordering occurs. In‐field magnetic force microscopy on exfoliated flakes confirms that the paramagnetic response at room temperature persists down to monolayers. Further, a correlation between the mixture of the oxidation states of iron and the critical ordering temperature is established, indicating a path to design materials with higher critical temperatures via oxidation state engineering.

This study describes the fabrication of hybrid two-dimensional (2D)-quantum dot (QD) MoS2–AgInS2 photoconductive devices through the mechanical pressing of a MoS2 flake onto an AgInS2 QD film. The devices exhibit an enhanced photoresponse at both continuous and modulated optical excitations, compared with the bare MoS2 or AgInS2 layer, due to the formation of a built-in electric field near the MoS2/AgInS2 interface. The continuous wave photoresponse is significantly higher due to the effective photoconductive gain when electrons flow freely through the MoS2 flake, whereas holes are effectively trapped in AgInS2 QDs. The study highlights the potential of hybrid 2D-QD MoS2–AgInS2 devices for photovoltaic and optoelectronic applications.

The problem with waste heat in solar panels has stimulated research on materials suitable for hybrid solar cells, which combine photovoltaic and thermoelectric properties. One such potential material is Cu₂ZnSnS₄ (CZTS). Here, we investigated thin films formed from CZTS nanocrystals obtained by “green” colloidal synthesis. The films were subjected to thermal annealing at temperatures up to 350 °C or flash-lamp annealing (FLA) at light-pulse power densities up to 12 J/cm². The range of 250–300 °C was found to be optimal for obtaining conductive nanocrystalline films, for which the thermoelectric parameters could also be determined reliably. From phonon Raman spectra, we conclude that in this temperature range, a structural transition occurs in CZTS, accompanied by the formation of the minor Cu_xS phase. The latter is assumed to be a determinant for both the electrical and thermoelectrical properties of CZTS films obtained in this way. For the FLA-treated samples, the film conductivity achieved was too low to measure the thermoelectric parameters reliably, although the partial improvement of the CZTS crystallinity is observed in the Raman spectra. However, the absence of the Cu_xS phase supports the assumption of its importance with respect to the thermoelectric properties of such CZTS thin films.