title: Biofunctionalized quantum dots for live monitoring of stem cells: applications in regenerative medicine.
abstract: OBJECTIVE
  This study aimed to live monitor the degree of endothelial progenitor cell (EPC) integration onto tissue-engineering scaffolds by conjugating relevant antibodies to quantum dots (QDs).
  
  
  METHODS
  Biocompatible mercaptosuccinic acid-coated QDs were functionalized with two different antibodies to EPC (CD133 with QDs of 640 nm wavelength [λ] and later-stage mature EPCs; and von Willebrand factor with QDs of λ595 and λ555 nm) using conventional carbomide and N-hydroxysuccinimide chemistry. Biofunctionalization was characterized with Fourier-transform infrared spectroscopy. Cell viability assays and gross morphology observations confirmed cytocompatibility and normal patterns of celluar growth. The antigens corresponding to each state of cell maturation were determined using a single excitation at λ488 nm.
  
  
  RESULTS
  The optimal concentrations of antibody-QD conjugates were biocompatible, hemocompatible and determined the state of EPC transformation to endothelial cells.
  
  
  CONCLUSIONS
  Antibody-functionalized QDs suggest new applications in tissue engineering of polymer-based implants where cell integration can potentially be monitored without requiring the sacrifice of implants.
authors.affiliation: UCL Centre for Nanotechnology & Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London, UK.
authors.forename: Achala
authors.initials: A
authors.lastname: de Mel
authors.forename: Jung-Taek
authors.initials: JT
authors.lastname: Oh
authors.forename: Bala
authors.initials: B
authors.lastname: Ramesh
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Seifalian
mesh_terms: D000071916:AC133 Antigen; D000906:Antibodies / Q000276:immunology; D015703:Antigens, CD / Q000378:metabolism; D001672:Biocompatible Materials / Q000737:chemistry / Q000494:pharmacology*; D048430:Cell Shape / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D001026:Coronary Artery Bypass; D042783:Endothelial Cells / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D005453:Fluorescence; D006023:Glycoproteins / Q000378:metabolism; D006461:Hemolysis / Q000187:drug effects; D006801:Humans; D008422:Materials Testing; D018613:Microscopy, Confocal; D010455:Peptides / Q000378:metabolism; D045663:Quantum Dots; D044968:Regenerative Medicine / Q000379:methods*; D017550:Spectroscopy, Fourier Transform Infrared; D013194:Staining and Labeling; D013234:Stem Cells / Q000166:cytology* / Q000187:drug effects* / Q000378:metabolism; D013870:Thiomalates / Q000737:chemistry / Q000494:pharmacology; D023822:Tissue Engineering
chemical_list: D000071916:AC133 Antigen; D000906:Antibodies; D015703:Antigens, CD; D001672:Biocompatible Materials; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; D013870:Thiomalates; C046062:2-thiomalic acid