Development of ultrabright semiconducting polymer dots for ratiometric pH sensing.
Semiconducting polymer-based nanoparticles (Pdots) have recently emerged as a new class of ultrabright probes for biological detection and imaging. This paper describes the development of poly(2,5-di(3',7'-dimethyloctyl)phenylene-1,4-ethynylene) (PPE) Pdots as a platform for designing Förster resonance energy transfer (FRET)-based ratiometric pH nanoprobes. We describe and compare three routes for coupling the pH-sensitive dye, fluorescein, to PPE Pdots, which is a pH-insensitive semiconducting polymer. This approach offers a rapid and robust sensor for pH determination using the ratiometric methodology where excitation at a single wavelength results in two emission peaks, one that is pH sensitive and the other one that is pH insensitive for use as an internal reference. The linear range for pH sensing of the fluorescein-coupled Pdots is between pH 5.0 and 8.0, which is suitable for most cellular studies. The pH-sensitive Pdots show excellent reversibility and stability in pH measurements. In this paper, we use them to measure the intracellular pH in HeLa cells following their uptake by endocytosis, thus demonstrating their utility for use in cellular and imaging experiments.
Department of Chemistry, University of Washington, Seattle, Washington 98195, USA.
Yang-Hsiang
YH
Chan
Changfeng
C
Wu
Fangmao
F
Ye
Yuhui
Y
Jin
Polina B
PB
Smith
Daniel T
DT
Chiu
D004705:Endocytosis; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D031541:Fluorescence Resonance Energy Transfer / Q000379:methods*; D005456:Fluorescent Dyes / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D006863:Hydrogen-Ion Concentration; D042541:Intracellular Space / Q000737:chemistry / Q000378:metabolism; D016014:Linear Models; D057054:Molecular Imaging; D053758:Nanoparticles / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism; D012666:Semiconductors
D005456:Fluorescent Dyes; D011108:Polymers; C473966:poly(phenylene ethynylene); D016650:Fluorescein-5-isothiocyanate
Adv Mater. 2010 Jul 27;22(28):2985-97
20535737
Anal Chem. 2000 Aug 1;72(15):3497-503
10952534
Chem Commun (Camb). 2010 Nov 28;46(44):8445-7
20886155
Small. 2006 Jun;2(6):723-6
17193111
Biophys J. 2009 Nov 4;97(9):2577-84
19883601
ACS Nano. 2008 Nov 25;2(11):2415-23
19206410
Science. 2005 Mar 25;307(5717):1962-5
15790856
Anal Chem. 2001 Jul 15;73(14):3240-6
11476221
Biochem J. 2002 Sep 15;366(Pt 3):689-704
12061891
Nat Mater. 2005 Jun;4(6):435-46
15928695
Science. 2005 Jan 28;307(5709):538-44
15681376
J Am Chem Soc. 2008 Apr 30;130(17):5720-5
18393422
Chem Rev. 2010 May 12;110(5):2709-28
19831417
Nanoscale. 2010 Oct;2(10):1999-2011
20697652
Nano Lett. 2004 Jan 1;4(1):11-18
28890669
J Colloid Interface Sci. 2009 Nov 1;339(1):266-70
19679316
J Virol. 1998 Dec;72(12):9645-55
9811698
Methods. 2008 Nov;46(3):143-51
18929663
Wiley Interdiscip Rev Nanomed Nanobiotechnol. 2009 Jan-Feb;1(1):98-110
20049782
Anal Bioanal Chem. 2007 Jun;388(3):645-54
17440714
J Am Chem Soc. 2006 Oct 18;128(41):13320-1
17031920
J Phys Chem C Nanomater Interfaces. 2007;111(7):2872-2878
18985164
Angew Chem Int Ed Engl. 2010 Dec 3;49(49):9436-40
20979060
J Am Chem Soc. 2008 Mar 26;130(12):3744-5
18321112
J Am Chem Soc. 2010 Nov 3;132(43):15410-7
20929226
Chem Commun (Camb). 2010 Apr 14;46(14):2408-10
20309464
News Physiol Sci. 2002 Feb;17:1-5
11821527
Nature. 2010 Nov 18;468(7322):406-11
20927102
Chem Soc Rev. 2006 Nov;35(11):1028-42
17057833
Anal Chem. 2003 Aug 1;75(15):3784-91
14572044
Proc Natl Acad Sci U S A. 2005 Oct 4;102(40):14284-9
16169907
Spectrochim Acta A Mol Biomol Spectrosc. 2007 Jun;67(2):517-21
16965933
Chem Res Toxicol. 2001 Sep;14(9):1170-6
11559030
Cancer Cell. 2008 Oct 7;14(4):335-43
18835035
Angew Chem Int Ed Engl. 2010 Jun 7;49(25):4246-9
20446280
Soft Matter. 2008 May 14;4(6):1169-1172
32907258
Bioconjug Chem. 2008 Aug;19(8):1635-9
18666791
Chem Rev. 2010 Oct 13;110(10):6260-79
20684570