title: Conjugation of antibodies to gold nanorods through Fc portion: synthesis and molecular specific imaging.
abstract: Anisotropic gold nanorods provide a convenient combination of properties, such as tunability of plasmon resonances and strong extinction cross sections in the near-infrared to red spectral region. These properties have created significant interest in the development of antibody conjugation methods for synthesis of targeted nanorods for a number of biomedical applications, including molecular specific imaging and therapy. Previously published conjugation approaches have achieved molecular specificity. However, the current conjugation methods have several downsides including low stability and potential cytotoxicity of bioconjugates that are produced by electrostatic interactions, as well as lack of control over antibody orientation during covalent conjugation. Here we addressed these shortcomings by introducing directional antibody conjugation to the gold nanorod surface. The directional conjugation is achieved through the carbohydrate moiety, which is located on one of the heavy chains of the Fc portion of most antibodies. The carbohydrate is oxidized under mild conditions to a hydrazide reactive aldehyde group. Then, a heterofunctional linker with hydrazide and dithiol groups is used to attach antibodies to gold nanorods. The directional conjugation approach was characterized using electron microscopy, zeta potential, and extinction spectra. We also determined spectral changes associated with nanorod aggregation; these spectral changes can be used as a convenient quality control of nanorod bioconjugates. Molecular specificity of the synthesized antibody targeted nanorods was demonstrated using hyperspectral, optical and photoacoustic imaging of cancer cell culture models. Additionally, we observed characteristic changes in optical spectra of molecular specific nanorods after their interactions with cancer cells; the observed spectral signatures can be explored for sensitive cancer detection.
authors: Department of Biomedical Engineering and §Texas Materials Institute, University of Texas at Austin, Austin, Texas 78712, United States.
authors: Pratixa P
authors: PP
authors: Joshi
authors: Soon Joon
authors: SJ
authors: Yoon
authors: William G
authors: WG
authors: Hardin
authors: Stanislav
authors: S
authors: Emelianov
authors: Konstantin V
authors: KV
authors: Sokolov
mesh_terms: D000327:Adsorption; D000818:Animals; D000906:Antibodies / Q000737:chemistry* / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D004354:Drug Screening Assays, Antitumor; D006046:Gold / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D008264:Macrophages / Q000187:drug effects; D051379:Mice; D057054:Molecular Imaging; D043942:Nanotubes / Q000737:chemistry*; D009369:Neoplasms / Q000175:diagnosis* / Q000188:drug therapy; D055672:Static Electricity; D013499:Surface Properties
chemical_list: D000906:Antibodies; D006046:Gold
references: ACS Nano. 2011 Jan 25;5(1):399-407
references: 21158483
references: Nano Lett. 2009 May;9(5):1798-805
references: 19351145
references: J Am Chem Soc. 2010 Nov 24;132(46):16417-22
references: 21043495
references: Technol Cancer Res Treat. 2004 Feb;3(1):33-40
references: 14750891
references: Nano Lett. 2009 Aug;9(8):2825-31
references: 19572747
references: Nano Lett. 2012 Oct 10;12(10):5304-10
references: 22920324
references: Photochem Photobiol. 2009 Jan-Feb;85(1):21-32
references: 19161395
references: Langmuir. 2011 Apr 19;27(8):4456-64
references: 21413796
references: Proc Natl Acad Sci U S A. 2005 Nov 1;102(44):15752-6
references: 16239346
references: Nano Lett. 2009 Oct;9(10):3612-8
references: 19645464
references: Cancer Res. 2010 Apr 15;70(8):3177-88
references: 20388791
references: Nano Lett. 2005 Apr;5(4):709-11
references: 15826113
references: Nano Lett. 2009 Feb;9(2):562-70
references: 19128006
references: Proc Natl Acad Sci U S A. 2010 May 11;107(19):8760-5
references: 20410458
references: Nano Lett. 2007 May;7(5):1318-22
references: 17430005
references: Adv Mater. 2009 Dec 28;21(48):4880-4910
references: 25378252
references: ACS Nano. 2011 Apr 26;5(4):2870-9
references: 21405102
references: Curr Opin Biotechnol. 2010 Aug;21(4):489-97
references: 20801636
references: J Biomed Opt. 2012 Jan;17(1):010701
references: 22352632
references: Acc Chem Res. 2008 Dec;41(12):1721-30
references: 18712884
references: Nat Mater. 2008 Jun;7(6):442-53
references: 18497851
references: Curr Opin Chem Biol. 2005 Oct;9(5):538-44
references: 16129649
references: Science. 2012 Mar 23;335(6075):1458-62
references: 22442475
references: Nano Lett. 2005 May;5(5):829-34
references: 15884879
references: Chem Rev. 2010 May 12;110(5):2783-94
references: 20387910
references: J Urol. 2008 Feb;179(2):748-53
references: 18082199
references: Trends Biotechnol. 2011 May;29(5):213-21
references: 21324541
references: Nat Biotechnol. 2004 Jan;22(1):47-52
references: 14704706
references: Lasers Surg Med. 2005 Sep;37(3):219-26
references: 16175635
references: J Am Chem Soc. 2006 Feb 15;128(6):2115-20
references: 16464114
references: Cancer Lett. 2008 Sep 28;269(1):57-66
references: 18541363
references: Opt Express. 2007 May 28;15(11):6583-8
references: 19546967
references: Nano Lett. 2007 Apr;7(4):941-5
references: 17335272
references: J Control Release. 2006 Sep 12;114(3):343-7
references: 16876898
references: Langmuir. 2007 Aug 14;23(17):9114-9
references: 17636999
references: J Phys Chem B. 2006 Apr 13;110(14):7238-48
references: 16599493
references: J Biomed Opt. 2008 May-Jun;13(3):034024
references: 18601569
references: Cytometry A. 2011 Jan;79(1):57-65
references: 21182183
references: J Am Chem Soc. 2011 Feb 23;133(7):2120-3
references: 21268581
references: Nano Lett. 2008 Oct;8(10):3461-7
references: 18767886
references: Angew Chem Int Ed Engl. 2012 Jan 16;51(3):636-41
references: 22086869
references: Nat Methods. 2010 Aug;7(8):603-14
references: 20676081
references: Langmuir. 2010 Jun 15;26(12):9328-33
references: 20356032
references: J Biomed Opt. 2007 May-Jun;12(3):034007
references: 17614715
references: Opt Express. 2008 Feb 4;16(3):1590-9
references: 18542237
references: Nat Nanotechnol. 2006 Oct;1(1):47-52
references: 18654141
references: Chem Soc Rev. 2011 Jul;40(7):3391-404
references: 21629885
references: J Biomed Opt. 2008 Jan-Feb;13(1):014022
references: 18315380
references: Acc Chem Res. 2008 Dec;41(12):1578-86
references: 18447366
references: Med Phys. 2010 Sep;37(9):4777-81
references: 20964197
references: Chem Commun (Camb). 2009 Apr 7;(13):1724-6
references: 19294275
references: Anal Chem. 2007 Jan 15;79(2):572-9
references: 17222022
references: Nat Protoc. 2008;3(2):314-20
references: 18274533
references: Nano Lett. 2009 Jan;9(1):287-91
references: 19072129
references: Pharm Res. 2011 Feb;28(2):279-91
references: 20872051
references: Biomed Opt Express. 2011 Jul 1;2(7):1828-35
references: 21750761
references: Small. 2008 Jan;4(1):153-9
references: 18081130
references: Biosens Bioelectron. 2010 Oct 15;26(2):404-10
references: 20729056
references: Nano Lett. 2007 Jun;7(6):1591-7
references: 17474783
references: Small. 2009 Mar;5(6):701-8
references: 19226599
references: Nanoscale. 2011 Apr;3(4):1724-30
references: 21321760
references: J Biomed Opt. 2011 May;16(5):056008
references: 21639576
references: Nano Rev. 2010;1:
references: 22110850
references: Nano Lett. 2009 Jun;9(6):2212-7
references: 18844426
references: Technol Cancer Res Treat. 2003 Dec;2(6):491-504
references: 14640761
references: Acc Chem Res. 2011 Oct 18;44(10):914-24
references: 21528889
references: Anal Chem. 2008 Feb 15;80(4):984-9
references: 18197636
references: J Neurooncol. 2011 Sep;104(2):439-48
references: 21221712
references: J Mater Chem. 2011 Jan 1;21(9):2841-2844
references: 21660122
references: Cancer Res. 2003 May 1;63(9):1999-2004
references: 12727808
references: Nano Lett. 2007 Dec;7(12):3798-802
references: 18020475
references: Proc Natl Acad Sci U S A. 2003 Nov 11;100(23):13549-54
references: 14597719
references: Appl Biochem Biotechnol. 1990 Feb;23(2):123-37
references: 2159262