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Tellurium is a heavy chemical element exhibiting chirality, anisotropy, and strong spin-orbit coupling; conse quently, displaying a huge potential in quantum hardware technologies. In this article, tellurium quantum dots, with sizes around 19 ± 3 nm and energy bandgap around 2.4 eV, were successfully synthesized by pulsed laser ablation in liquids (PLAL). The synthesis was performed by using a nanosecond Nd:YAG laser emitting at 1064 nm and pulsing the laser beam at 1 kHz. Toluene (C6H5CH3) was used as a solvent to avoid oxidation of the dots. Non-polarized and polarized Raman spectroscopy as well as X-Ray diffraction were performed on the dots to study their quantum confinement and anisotropy. Finally, strongly confined tellurium quantum dots were obtained; and, their properties underline their potential as quantum light sources. 

Ionic liquids are an interesting class of materials that have recently been utilized as chemotherapeutic agents in cancer therapy. Aniline blue, a commonly used biological staining agent, was used as a counter ion to trihexyltetradecylphosphonium, a known cytotoxic cation. A facile, single step ion exchange reaction was performed to synthesize a fluorescent ionic liquid, trihexyltetradecylphosphonium aniline blue. Aqueous nanoparticles of this hydrophobic ionic liquid were prepared using reprecipitationmethod. The newly synthesized ionic liquid and subsequent nanoparticles were characterized using various spectroscopic techniques. Transmission electron microscopy and zeta potential measurements were performed to characterize the nanoparticles’ morphology and surface charge. The photophysical properties of the nanoparticles and the parent aniline blue compound were studied using absorption and fluorescence spectroscopy. Cell viability studies were conducted to investigate the cytotoxicity of the newly developed trihexyltetradecylphosphonium aniline blue nanoparticles in human breast epithelial cancer cell line (MCF-7) and its corresponding normal epithelial cell line (MCF-10A) in vitro . The results revealed that the synthesized ionic nanomedicines were more cytotoxic (lower IC 50 ) than the parent chemotherapeutic compound in MCF-7 cells. Nanoparticles of the synthesized ionic liquid were also shown to be more stable in both aqueous and cellular media and more selective than parent compounds towards cancer cells. 

Bismuth oxide is an important bismuth compound having applications in electronics, photo-catalysis and medicine. At the nanoscale, bismuth oxide experiences a variety of new physico-chemical properties because of its increased surface to volume ratio leading to potentially new applications. In this manuscript, we report for the very first time the synthesis of bismuth oxide (Bi 2 O 3 ) nano-flakes by pulsed laser ablation in liquids without any external assistance (no acoustic, electric field, or magnetic field). The synthesis was performed by irradiating, pure bismuth needles immerged in de-ionized water, at very high fluence ∼160 J cm −2 in order to be highly selective and only promote the growth of two-dimensional structures. The x - and y -dimensions of the flakes were around 1 μm in size while their thickness was 47.0 ± 12.7 nm as confirmed by AFM analysis. The flakes were confirmed to be α- and γ-Bi 2 O 3 by SAED and Raman spectroscopy. By using this mixture of flakes, we demonstrated that the nanostructures can be used as antimicrobial agents, achieving a complete inhibition of Gram positive (MSRA) and Gram negative bacteria (MDR-EC) at low concentration, ∼50 ppm.