Incorporation of AuNP-PLL nanocomplexes in DPSC: a new tool for 3D analysis in pulp regeneration

  • Michelle Tillmann Biz
  • Carolina Cucco
  • Bruno Neves CavalcantiEmail author
Original Article



To assess the viability of dental pulp stem cells loaded with gold nanoparticles complexed with poly (l-lysine) (AuNP-PLL) and to track the cellular behavior in a 3D analysis by micro-CT.

Materials and methods

DPSC (dental pulp stem cells) were cultured and incorporated with AuNP-PLL (0.2 mg/ml) and assessed for cell viability (24 h, 48 h, and 72 h) using MTS assay. Apoptosis/cell death index and cell cycle were analyzed by propidium iodide. AuNP-PLL-RITC were used for observation in confocal microscopy and quantification of the incorporation rates. Cells were also suspended in agarose and analyzed three-dimensionally in μCT, assessing their radiopacity. Quantitative data (cell viability and apoptosis) were analyzed by t test (p < 0.05).


AuNP-PLL labeling did not affect cellular viability in any of the periods analyzed nor interfered with the apoptosis index of DPSC. AuNP-PLL nanocomplexes were identified in the cytoplasm of cells by immunofluorescence, mainly in the perinuclear region. The observed incorporation rate was 98%. Micro-CT analysis has shown that incorporated cells are now visible using x-ray, with a clear increase in radiopacity when compared to the control group (non-incorporated cells).


These results indicate that it is possible to incorporate AuNP-PLL complex into DPSC and track the cells by using μCT; furthermore, this incorporation of 0.2 mg/ml of AuNP-PLL does not interfere in the DPSC basic behavior.

Clinical relevance

This methodology can be a useful tool for cellular labeling to observe cell behavior and their interaction with scaffolds in a 3D manner, opening an array of new approaches in regenerative endodontics.


Tissue engineering Stem cells Dental pulp Scaffold Endodontics 



The authors would like to acknowledge use of the University of Iowa Central Microscopy Research Facility, a core resource supported by the Vice President for Research & Economic Development, the Holden Comprehensive Cancer Center and the Carver College of Medicine.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

For this type of study, ethical approval is not required.

Informed consent

For this type of study, formal consent is not required.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Departamento de Ciências MorfológicasUniversidade Federal de Santa CatarinaFlorianopolisBrazil
  2. 2.Department of EndodonticsUniversity of Iowa College of Dentistry and Dental ClinicsIowa CityUSA

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