A simple, compact, low-cost, highly efficient thermometer based on green fluorescence of Er3+/Yb3+-codoped NaYF4 microcrystals.

We developed a highly efficient optical thermometer based on intensity ratio of upconversion green fluorescence of Er3+/Yb3+-codoped NaYF4 microcrystals. The sensor consists simply of a 980nm laser diode, one narrow-band interference filter, two lenses, one Si-photocell and one multimeter, while being without use of spectrometer and additional electronics. The device not only has a simple, compact structure (hence a low cost), but also displays highly efficient sensing performance, characterized by large signal-to-noise ratio due to strong fluorescence intensity, high thermal resolution and sensitivity, which have the values 1.3K and 1.24×10-2K-1, respectively, at the physiological temperature 310K. The excellent sensing performance of the device was further confirmed by the results of the measurements repeated using a spectrometer. The thermometer is highly generalized that can be applied to other luminescent materials, and shows great potential for the physiological temperature sensing in biological tissues and cells.

[1]  F. Cussó,et al.  Polarization effects on the line-strength calculations of Er3+-doped LiNbO3 , 1996 .

[2]  X. Loh,et al.  Metal carbonyl-gold nanoparticle conjugates for highly sensitive SERS detection of organophosphorus pesticides. , 2017, Biosensors & bioelectronics.

[3]  Xian Jun Loh,et al.  Cationic star copolymers based on β-cyclodextrins for efficient gene delivery to mouse embryonic stem cell colonies. , 2015, Chemical communications.

[4]  L. Luo,et al.  Upconversion emission in Er-doped and Er/Yb-codoped ferroelectric Na0.5Bi0.5TiO3 and its temperature sensing application , 2014 .

[5]  O. Wolfbeis,et al.  Luminescent probes and sensors for temperature. , 2013, Chemical Society reviews.

[6]  Francisco Sanz-Rodríguez,et al.  Temperature sensing using fluorescent nanothermometers. , 2010, ACS nano.

[7]  Peng Du,et al.  Optical temperature sensor based on upconversion emission in Er-doped ferroelectric 0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 ceramic , 2014 .

[8]  O. Savchuk,et al.  Novel low-cost, compact and fast signal processing sensor for ratiometric luminescent nanothermometry , 2016 .

[9]  Bin Dong,et al.  Size dependence of the upconverted luminescence of NaYF4:Er,Yb microspheres for use in ratiometric thermometry. , 2014, Physical chemistry chemical physics : PCCP.

[10]  Martin Wegener,et al.  Three-dimensional micro-printing of temperature sensors based on up-conversion luminescence , 2015 .

[11]  H. Moos,et al.  MULTIPHONON ORBIT-LATTICE RELAXATION OF EXCITED STATES OF RARE-EARTH IONS IN CRYSTALS. , 1968 .

[12]  Zhitang Song,et al.  Optical temperature sensing by upconversion luminescence of Er doped Bi5TiNbWO15ferroelectric materials , 2014 .

[13]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[14]  Inocencio R. Martín,et al.  Effects of Er3+ concentration on thermal sensitivity in optical temperature fluorotellurite glass sensors , 2013 .

[15]  S. Wade.  Temperature measurement using rare earth doped fibre fluorescence , 1999 .

[16]  Andrew G. Glen,et al.  APPL , 2001 .

[17]  V. K. Rai,et al.  Optical investigation in shuttle like BaMoO4:Er3+–Yb3+ phosphor in display and temperature sensing , 2015 .

[18]  C. Duan,et al.  Optical thermometry based on upconverted luminescence in transparent glass ceramics containing NaYF4:Yb3+/Er3+ nanocrystals , 2014 .

[19]  V. Lojpur,et al.  Luminescence thermometry below room temperature via up-conversion emission of Y2O3:Yb3+,Er3+ nanophosphors , 2014 .

[20]  N. Hashim,et al.  Ionic liquid entrapment by an electrospun polymer nanofiber matrix as a high conductivity polymer electrolyte , 2015 .

[21]  Shan Jiang,et al.  Multicolor Core/Shell‐Structured Upconversion Fluorescent Nanoparticles , 2008 .

[22]  H. Ramanarayan,et al.  An experimental and theoretical investigation of the anisotropic branching in gold nanocrosses. , 2016, Nanoscale.

[23]  Hui Zhou,et al.  Highly Efficient Supramolecular Aggregation-Induced Emission-Active Pseudorotaxane Luminogen for Functional Bioimaging. , 2017, Biomacromolecules.

[24]  Yingying Xu,et al.  Blockade of oral tolerance to ovalbumin in mice by silver nanoparticles. , 2015, Nanomedicine.

[25]  Xian Jun Loh,et al.  Effective near-infrared photodynamic therapy assisted by upconversion nanoparticles conjugated with photosensitizers , 2015, International journal of nanomedicine.

[26]  U. Rodríguez-Mendoza,et al.  2CaO·Al2O3:Er3+ glass: An efficient optical temperature sensor , 2016 .

[27]  Miroslav D. Dramićanin,et al.  Multifunctional Eu3+- and Er3+/Yb3+-doped GdVO4 nanoparticles synthesized by reverse micelle method , 2014, Scientific Reports.

[28]  F. Cussó,et al.  Temperature Sensing with Up-Converting Submicron-Sized LiNbO3:Er3+/Yb3+ Particles , 2011 .

[29]  Kaushal Kumar,et al.  Er3+–Yb3+ doped vanadate nanocrystals: A highly sensitive thermographic phosphor and its optical nanoheater behavior , 2015 .

[30]  Miss A.O. Penney.  (b) , 1974, The New Yale Book of Quotations.

[31]  L. Carlos,et al.  Lanthanide–Organic Framework Nanothermometers Prepared by Spray‐Drying , 2015 .

[32]  X. Loh,et al.  Effective Targeted Photothermal Ablation of Multidrug Resistant Bacteria and Their Biofilms with NIR‐Absorbing Gold Nanocrosses , 2016, Advanced healthcare materials.

[33]  Kenneth T. V. Grattan,et al.  Comparison of fluorescence-based temperature sensor schemes: Theoretical analysis and experimental validation , 1998 .