Versatile Synthesis Strategy for Carboxylic Acid
Download
1 / 36

Upconversion - PowerPoint PPT Presentation


  • 115 Views
  • Uploaded on

this is ppt on upconversion

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Upconversion' - 9798120263


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Versatile Synthesis Strategy for Carboxylic Acid-functionalized Upconverting Nanophosphors as Biological Labels

演講者:洪柏楷

Zhigang Chen, Huili Chen, He Hu, Mengxiao Yu, Fuyou Li,*

Qiang Zhang,Zhiguo Zhou, Tao Yi, and Chunhui Huang*

J. AM. CHEM. SOC. 2008, 130, 3023-3029


Outline
Outline

  • Phosphors

  • Synthesis of Oleic Acid-Capped UCNPs

  • Converting Hydrophobic UCNPs into Hydrophilic

  • Preparation of Streptavidin-Functionalized UCNPs

  • Detection of DNA


Phosphors
Phosphors

  • Downconverting phosphors

  • Upconverting phosphors


Downconversion fluorescent materials
Downconversion fluorescent materials

  • 1. Organic dyes

  • 2. Semiconductor nanocrystal


Up converting rare earth nanophosphors ucnps
Up-converting rare-earth nanophosphors (UCNPs)

  • 1. sharp absorption and emission lines

  • 2. high quantum yields

  • 3. long lifetimes

  • 4. photostability


oleic acid

2,6-diaminohexanoic acid (Lysine)

1-ethyl-3-(3-dimethylaminopropyl) carbodiimidehydrochloride (EDC)


Hydroxy-2,5-dioxopyrrolidine-3-

sulfonicacid sodium salt (Sulfo-NHS)

4-Morpholineethanesulfonic acid (MES)

2-Amino-2-hydroxymethyl-propane-1,3-diol (Tris)


Synthesis of oleic acid capped ucnps
Synthesis of Oleic Acid-Capped UCNPs

NaOH + water + ethanol + oleic acid

rare-earth chloride (LnCl3)

1.0 M NaF

transfer to autoclave 160 °C 8 h

cyclohexane + ethanol

oleic acid-capped UCNPs

Ln: 78 mol% Y + 20 mol%Yb + 2 mol%Er


Nayf 4 20 mol yb 2 mol er
NaYF4: 20 mol%Yb, 2 mol % Er


Converting hydrophobic ucnps into hydrophilic
Converting Hydrophobic UCNPs into Hydrophilic

UCNP + cyclohexane + tert-butanol + water

5 wt % K2CO3 aqueous solution

KMnO4 + NaIO4 (Lemieux-von Rudloff reagent)

40 °C 48 h.

wash with deionized water acetone ethanol.

HCl (50 mL) pH 4-5

30 min

washed twice with deionized water

hydrophilic UCNPs



TEM

NaYF4:Yb,Er

oxidized NaYF4:Yb,Er


TEM

NaYF4:Yb, Tm

oxidized NaYF4:Yb, Tm


TEM

NaYF4:Yb, Ho

oxidized NaYF4:Yb, Ho


Edxa spectra
EDXA spectra

oxidized NaYF4:Yb,Er

NaYF4:Yb,Er


Xrd pattern
XRD pattern

* cubic phase

▼hexagonal phase

oxidized NaYF4:Yb,Er

NaYF4:Yb,Er


1 h nmr spectra
1H NMR Spectra

oxidized NaYF4

undoped NaYF4


Ftir spectra
FTIR spectra

oxidized NaYF4:Yb,Er

NaYF4:Yb,Er


Thermogravimetric analysis tga
Thermogravimetric analysis (TGA)

7.55 %

oxidized NaYF4:Yb,Er

NaYF4:Yb,Er

11.32 %


Oxidized nayf 4 yb er1
Oxidized NaYF4:Yb,Er

water

DMF

DMSO



Luminescence
Luminescence

continuous-wave excitation at 980 nm

red filter

green filter


Luminescence spectra
Luminescence spectra

2H11/2 to 4I15/2

(A) NaYF4:Yb,Er

(B) Oxidized

NaYF4:Yb,Er

4S3/2 to 4I15/2

4F9/2 to 4I15/2

(I540 /I654 ) decrease



Energy level diagram
Energy level diagram

Leyu Wang ; Yadong Li Chem. Mater. 2007, 19, 727-734



Preparation of streptavidin functionalized ucnps
Preparation of Streptavidin-Functionalized UCNPs

oxidized NaYF4:Yb,Er + EDC + sulfo-NHS + MES buffer 8 h

water

PBS buffer solution

containing streptavidin 4 °C 48 h

Lysine water

Streptavidin-Functionalized

UCNPs



Oligonucleotide
Oligonucleotide

5'-(biotin)-GATGAGTATTGATGC-3 '

(as Capture-DNA)

5'-CGAATAGTTCCATTG-(TAMRA)-3 '

(as Report-DNA)

5 '-CAATGGAACTATTCG GCATCAATACTCATC-3 '(as Target-DNA)



Tarma labeled reporter dna
TARMA-labeled reporter DNA

absorption

emission

oxidized NaYF4: Yb, Er


Detection of dna
Detection of DNA

streptavidin-functionalized UCNPs + Report-DNA + Capture-DNA + buffered solution.

Target-DNA

37 °C for 20 min

980 nm

luminescence

spectrum



Dna nanosensors based on ucnps1
DNA nanosensors based on UCNPs

Fluorescence resonant energy transfer


Conclusions
Conclusions

  • We have demonstrated a new, efficient and versatile procedure for converting hydrophobic UCNPs into water-soluble and carboxylic acid-functionalized derivatives by directly oxidizing oleic acid ligands to azelaic acid.

  • This procedure is not limited to hydrophobic UCNPs,and it can easily be applied to other hydrophobic nanoparticles (including rare earth, semiconductor and metal nanoparticles) where only surface ligands can be oxidized.

  • The presence of free carboxylic acid groups on the surface of azelaic acid-capped UCNPs allows further conjugation with various biomolecules, and streptavidin-functionalized UCNPs derived from azelaic acid-capped precursors provides a novel approach for detecting and/or binding to a broad range of biotinylated proteins or antibodies .


ad