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Abstract: In this paper luminescent materials consisting of Ln1.9Pr0.1(WO4)3 where Ln=Gd or La immobilized in silica xerogel matrix have been obtained through a sol–gel approach. The spectroscopic investigations of these materials are presented. Steady state luminescence, luminescence excitation spectra as well as time resolved emission spectra have been measured. The obtained strong red emission due to the excitation energy transfer from group to Pr(III) ion upon excitation at λ exc =240nm is the main result of this paper. Analysis of the luminescence kinetics of Pr(III) ions in studied materials has been performed. The decay curves of Pr(III) luminescence related to 3P0 → 3H4 and 3P0 → 3F2 transitions are reported. High emission intensity and easy preparation of these materials make them promising red phosphors for applications as luminescent materials. [Copyright &y& Elsevier]

Abstract: Apparatus to study time-evolution of emission spectra over very wide time and spectral range is described. Excitation part of the equipment consists of solid state Nd:YAG laser and optical parametric generator. The heart of the detection system consists of spectrograph and streak camera. The significance of optics and electronics built in the system for proper, fast and convenient measurements is underlined. The results of donor–acceptor energy transfer in a rigid polyvinyl alcohol matrix serve here as an example of application our equipment to study complex systems. [Copyright &y& Elsevier]

Abstract: Lanthanium tungstates (where Ln=La or Gd) doped with dysprosium ion and incorporated into silica xerogel were prepared by the sol–gel process. X-ray diffraction (XRD) and transmission electron microscopy (TEM) methods were used to investigate structural and morphological properties of the obtained materials. Reflectance and emission spectra were measured at room temperature. These materials exhibit strong absorption band in the UV region. Moreover, photoluminescence spectra contain the characteristic emission bands of Dy3+ in the host matrix. In particular, yellow emission at 575nm () and blue emission at 484nm () were observed due to the excitation energy transfer from group to Dy(III) ion upon excitation at λ exc =240nm which is the important finding result of this paper. These results are supplemented by the analysis of the luminescence kinetics of Dy(III) ions in the studied materials. [Copyright &y& Elsevier]

Abstract Plasmonic platforms allow reliable visualization and detection of Valrubicin, a medically important chemotherapeutic molecule. Different plasmonic platforms constructed with silver nanoparticles (AgNps) or core-shell nanostructures (Ag@SiO 2) deposited and arranged on semitransparent silver/gold mirrors were exploited in the study using various spectroscopic and microscopic techniques. It is shown that the developed new plasmonic platform provides new quality of sensitive detection of the examined anticancer drug. Due to the interactions of the specimen with surface plasmons the brightness achievable in microscopic imaging of Valrubicin can be enhanced even 50 times for platforms containing core-shell nanoparticles. Graphical abstract Image 1 Highlights • New plasmonic platforms (pp) for detection of Valrubicin are successfully constructed. • Fluorescence enhancement is significant for pp containing core-shell nanoparticles. • The obtained pp with core-shell nanoparticles occurred more stable for longer time than those with silver nanoparticles. [ABSTRACT FROM AUTHOR]

The article presents an approach for determination of low activity hydrolases down to the nanoscale amount. It consists in a specific design of fluorescent indicator using Excited-State Intramolecular Proton-Transfer (ESIPT) phenomenon and enhancement of its fluorescence on the metal surface (Metal Enhanced Fluorescence – MEF). The developed approach is tested with β-glucosidase using novel ESIPT fluorescent indicator from the flavonol family. [ABSTRACT FROM AUTHOR]