High-quality crystals of monoclinic KLu(WO4)2, shortly KLuW, were grown with sizes sufficient for its characterization and substantial progress was achieved in the field of spectroscopy and laser operation with Yb 3+ -and Tm 3+ -doping. We review the growth methodology for bulk KLuW and epitaxial layers, its structural, thermo-mechanical, and optical properties, the Yb 3+ and Tm 3+ spectroscopy, and present laser results obtained in several operational regimes both with Ti:sapphire and direct diode laser pumping using InGaAs and AlGaAs diodes near 980 and 800 nm, respectively. The slope efficiencies with respect to the absorbed pump power achieved with continuous-wave (CW) bulk and epitaxial Yb:KLuW lasers under Ti:sapphire laser pumping were ≈ 57 and ≈ 66%, respectively. Output powers as high as 3.28 W were obtained with diode pumping in a simple two-mirror cavity where the slope efficiency with respect to the incident pump power reached ≈ 78%. Passively Q-switched laser operation of bulk Yb:KLuW was realized with a Cr:YAG saturable absorber resulting in oscillation at ≈ 1031 nm with a repetition rate of 28 kHz and simultaneous Raman conversion to ≈ 1138 nm with maximum energies of 32.4 and 14.4 µJ, respectively. The corresponding pulse durations were 1.41 and 0.71 ns. Passive mode-locking by a semiconductor saturable absorber mirror (SESAM) produced bandwidth-limited pulses with duration of 81 fs (1046 nm, 95 MHz) and 114 fs (1030 nm, 101 MHz) for bulk and epitaxial Projection of the KLu(WO4)2 structure parallel to the b crystallographic direction [010].Yb:KLuW lasers, respectively. Slope efficiency as high as 69% with respect to the absorbed power and an output power of 4 W at 1950 nm were achieved with a diodepumped Tm:KLuW laser. The slope efficiency reached with an epitaxial Tm:KLuW laser under Ti:sapphire laser pumping was 64 %. The tunability achieved with bulk and epitaxial Tm:KLuW lasers extended from 1800 to 1987 nm and from 1894 to 2039 nm, respectively.

We report a theranostic nanoparticle that can express ultrasound (US) imaging and simultaneous therapeutic functions for cancer treatment. We developed doxorubicin-loaded calcium carbonate (CaCO3) hybrid nanoparticles (DOX-CaCO3-MNPs) through a block copolymer templated in situ mineralization approach. The nanoparticles exhibited strong echogenic signals at tumoral acid pH by producing carbon dioxide (CO2) bubbles and showed excellent echo persistence. In vivo results demonstrated that the DOX-CaCO3-MNPs generated CO2 bubbles at tumor tissues sufficient for echogenic reflectivity under a US field. In contrast, the DOX-CaCO3-MNPs located in the liver or tumor-free subcutaneous area did not generate the CO2 bubbles necessary for US contrast. The DOX-CaCO3-MNPs could also trigger the DOX release simultaneously with CO2 bubble generation at the acidic tumoral environment. The DOX-CaCO3-MNPs displayed effective antitumor therapeutic activity in tumor-bearing mice. The concept described in this work may serve as a useful guide for development of various theranostic nanoparticles for US imaging and therapy of various cancers.

Development of nontoxic, tumor-targetable, and potent in vivo RNA delivery systems remains an arduous challenge for clinical application of RNAi therapeutics. Herein, we report a versatile RNAi nanoplatform based on tumor-targeted and pH-responsive nanoformulas (NFs). The NF was engineered by combination of an artificial RNA receptor, Zn(II)-DPA, with a tumor-targetable and drug-loadable hyaluronic acid nanoparticle, which was further modified with a calcium phosphate (CaP) coating by in situ mineralization. The NF can encapsulate small-molecule drugs within its hydrophobic inner core and strongly secure various RNA molecules (siRNAs, miRNAs, and oligonucleotides) by utilizing Zn(II)-DPA and a robust CaP coating. We substantiated the versatility of the RNAi nanoplatform by demonstrating effective delivery of siRNA and miRNA for gene silencing or miRNA replacement into different human types of cancer cells in vitro and into tumor-bearing mice in vivo by intravenous administration. The therapeutic potential of NFs coloaded with an anticancer drug doxorubicin (Dox) and multidrug resistance 1 gene target siRNA (siMDR) was also demonstrated in this study. NFs loaded with Dox and siMDR could successfully sensitize drug-resistant OVCAR8/ADR cells to Dox and suppress OVCAR8/ADR tumor cell proliferation in vitro and tumor growth in vivo. This gene/drug delivery system appears to be a highly effective nonviral method to deliver chemo- and RNAi therapeutics into host cells.

Single cell encoding with quantum dots as live cell optical tracers for deriving proliferation parameters has been developed using modelling to investigate cell cycle and proliferative outputs of human osteosarcoma cells undergoing mitotic bypass and endocycle routing. A computer-based simulation of the evolving cell population provides information on the dilution and segregation of nanoparticle dose cell by cell division and allows quantitative assessment of patterns of division, at both single cell and including whole population level cell cycle routing, with no a-priori knowledge of the population proliferation potential. The output therefore provides a unique mitotic distribution function that represents a convolution of cell cycle kinetics (cell division) and the partitioning coefficient for the labelled cell compartment (daughter-daughter inheritance or lineage asymmetry). The current study has shown that the cellular quantum dot fluorescence reduced over time as the particles were diluted by the process of cell division and had the properties of a non-random highly asymmetric event. Asymmetric nanoparticle segregation in the endosomal compartment has major implications on cell-fate determining signaling pathways and could lead to an understanding of the origins of unique proliferation and drug-resistance characteristics within a tumour cell lineage.

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Nanothermometry methods with intracellular sensitivities have the potential to make important contributions to fundamental cell biology and medical fields, as temperature is a relevant physical parameter for molecular reactions to occur inside the cells and changes of local temperature are well identified therapeutic strategies. Here we show how the GFP can be used to assess temperature-based on a novel fluorescence peak fraction method. Further, we use standard GFP transfection reagents to assess temperature intracellularly in HeLa cells expressing GFP in the mitochondria. High thermal resolution and sensitivity of around 0.26% °C −1 and 2.5% °C −1 , were achieved for wt-GFP in solution and emGFP-Mito within the cell, respectively. We demonstrate that the GFP-based nanothermometer is suited to directly follow the temperature changes induced by a chemical uncoupler reagent that acts on the mitochondria. The spatial resolution allows distinguishing local heating variations within the different cellular compartments. Our discovery may lead to establishing intracellular nanothermometry as a standard method applicable to the wide range of live cells able to express GFP.

Two-photon polymerization (TPP) is capable of fabricating 3D structures with dimensions from sub-µm to a few hundred µm. As a direct laser writing (DLW) process, fabrication time of 3D TPP structures scale with the third order, limiting its use in large volume fabrication. Here, we report on a scalable fabrication method that cuts fabrication time to a fraction. A parallelized 9 multi-beamlets DLW process, created by a fixed diffraction optical element (DOE) and subsequent stitching are used to fabricate large periodic high aspect ratio 3D microstructured arrays with sub-micron features spanning several hundred of µm 2. The wall structure in the array is designed with a minimum of traced lines and is created by a low numerical aperture (NA) microscope objective, leading to self-supporting lines omitting the need for line-hatching. The fabricated periodic arrays are applied in a cell-3D microstructure interaction study using living HeLa cells. First indications of increased cell proliferation in the presence of 3D microstructures compared to planar surfaces are obtained. Furthermore, the cells adopt an elongated morphology when attached to the 3D microstructured surfaces. Both results constitute promising findings rendering the 3D microstructures a suited tool for cell interaction experiments, e.g. for cell migration, separation or even tissue engineering studies. 3D fabrication approaches including electro-spinning, nano-imprinting, additive 3D printing of ceramics, metals and plastics together with other forms of bottom-up techniques, have revolutionized tissue and organ engineering, cell migration research and other applications in biomedical research 1-6. Additionally, advanced light-induced material processing techniques have been developed including mask-less and rapid micro-fabrication and-machining, e.g. for surface structuring, ablation and modifications 7-10. Belonging to this class of methods is direct laser writing (DLW) based micro-fabrication, where single-photon DLW can fabricate 2D and 2.5D type structures, while the inherent sectioning capability of multi-photon based DLW allows the fabrication of 3D microstructures 11-14. DLW has shown versatility in the fabrication of high-quality micro-optical elements 12 , waveguides 15 , and micro-machines 16. Laser-based manufacturing is capable of processing bio-compatible materials 17-19. As an optical technique DLW is limited by optical diffraction. Therefore, achievable feature sizes relate to the wavelength of the light source used. The microfabrication resolution furthermore is governed by the material properties, including the polymerization or ablation thresholds. The combination of these two aspects ultimately may allow for fabricating feature sizes well below the optical diffraction limit 20-22. The DLW-based polymerization fabrication process is based on tracing the contours of the structure design in a photosensitive material, followed by a development step to remove the developed/undeveloped polymer to obtain the final microfabricated structure....

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