Imaging the intracellular degradation of biodegradable polymer nanoparticles

• Anne-Kathrin Barthel,
• Martin Dass,
• Melanie Dröge,
• Jens-Michael Cramer,
• Daniela Baumann,
• Markus Urban,
• Katharina Landfester,
• Volker Mailänder and
• Ingo Lieberwirth

Beilstein J. Nanotechnol. 2014, 5, 1905–1917, doi:10.3762/bjnano.5.201

• biological environments, intracellular degradation processes have been examined only to a very limited extent. PLLA nanoparticles with an average diameter of approximately 120 nm were decorated with magnetite nanocrystals and introduced into mesenchymal stem cells (MSCs). The release of the magnetite

• ., number of detached magnetite crystals, and the number of nanoparticles in one endosome), we demonstrate the importance of TEM studies for such applications in addition to fluorescence studies (flow cytometry and confocal laser scanning microscopy). Keywords: biodegradation; mesenchymal stem cells; PLLA

• expected for the measured fluorescence intensity when compared to that measured. The majority of measured intensities lie below the expected values. Parallel to each cell experiment, the doubling time of our respective mesenchymal stem cells was determined to be 48 h in the presence of the respective PLLA

Carbon-based smart nanomaterials in biomedicine and neuroengineering

• Antonina M. Monaco and
• Michele Giugliano

Beilstein J. Nanotechnol. 2014, 5, 1849–1863, doi:10.3762/bjnano.5.196

• expression of genes responding to oxidative stress were observed [73]. However, Xing et al. [74] observed that embryonic stem cells responded to incubation with NDs with an increased expression of MOGG-1 and P53, which are proteins related to DNA repair processes. This genotoxicity was increased when cells

• interpret these results in terms of a possible application for neural stimulation. Graphene-based substrates have also been investigated as scaffolds for growth and for the differentiation of stem cells [142][143]. The differentiation into neurons of human neural stem cells (hNSCs), cultured on graphene has

• nanogrids, further enhanced by means of a repeated photo stimulation. Li and co-workers [146] designed a three-dimensional graphene foam scaffold for neural stem cells. This scaffold allowed the formation of a three-dimensional neural network, resulting in an excellent substrate for cell adhesion and

Influence of surface-modified maghemite nanoparticles on in vitro survival of human stem cells

• Michal Babič,
• Daniel Horák,
• Lyubov L. Lukash,
• Tetiana A. Ruban,
• Yurii N. Kolomiets,
• Svitlana P. Shpylova and
• Oksana A. Grypych

Beilstein J. Nanotechnol. 2014, 5, 1732–1737, doi:10.3762/bjnano.5.183

• the modified particles were characterized by transmission electron microscopy and dynamic light scattering with regard to morphology, particle size and polydispersity. In vitro survival of human stem cells was then investigated by using the methyl thiazolyl tetrazolium (MTT) assay, which showed that D

• -mannose- and poly(N,N-dimethylacrylamide)-coated γ-Fe2O3 particles exhibit much lower level of cytotoxicity than the non-coated γ-Fe2O3. Keywords: maghemite; magnetic; MTT assay; nanoparticles; stem cells; Introduction One of the most important applications of nanoparticles in biomedicine is the direct

• labeling of cells in order to track them both in diagnostics and therapeutics [1][2]. For example, mesenchymal [3], neural [4], and bone marrow [5] stem cells, as well as other cells are widely labeled by surface-coated iron oxide nanoparticles. Other applications of nanoparticles involve the delivery of

Influence of the PDMS substrate stiffness on the adhesion of Acanthamoeba castellanii

• Sören B. Gutekunst,
• Carsten Grabosch,
• Alexander Kovalev,
• Stanislav N. Gorb and
• Christine Selhuber-Unkel

Beilstein J. Nanotechnol. 2014, 5, 1393–1398, doi:10.3762/bjnano.5.152

• and position themselves [6]. Once grown on a substrate with defined elasticity, cells adapt their own elasticity to the elasticity of their environment [7]. But not only differentiated cells are influenced by substrate stiffness. For stem cells it has been demonstrated that their differentiation is

• substrate. The increase of adhesion area with decreasing Young`s modulus is opposite to the behavior of human mesenchymal stem cells [33] but is in good agreement with the trend observed in studies on neural stem cell cultures [34]. This result is reasonable, as during the infection process, A. castellanii

Mimicking exposures to acute and lifetime concentrations of inhaled silver nanoparticles by two different in vitro approaches

• Fabian Herzog,
• Kateryna Loza,
• Sandor Balog,
• Martin J. D. Clift,
• Matthias Epple,
• Peter Gehr,
• Alke Petri-Fink and
• Barbara Rothen-Rutishauser

Beilstein J. Nanotechnol. 2014, 5, 1357–1370, doi:10.3762/bjnano.5.149

• proliferation and migration (chemotaxis) both decreased, and the release of cytokines was affected. Increased IL-8 and decreased IL-6 and vascular endothelial growth factor (VEGF) levels were detected at high Ag NP concentrations [65]. These studies however, were obtained with human mesenchymal stem cells

Nanodiamond-DGEA peptide conjugates for enhanced delivery of doxorubicin to prostate cancer

• Amanee D Salaam,
• Patrick Hwang,
• Roberus McIntosh,
• Hadiyah N Green,
• Ho-Wook Jun and
• Derrick Dean

Beilstein J. Nanotechnol. 2014, 5, 937–945, doi:10.3762/bjnano.5.107

• tissues, the ND-DGEA conjugates were designed to distinguish between cells that overexpress α2β1 integrin, bone metastatic prostate cancers cells (PC3), and cells that do not, human mesenchymal stem cells (hMSC). Utilizing the ND-DGEA+DOX system, the efficacy of 1 µg/mL and 2 µg/mL DOX doses increased

• ) was used to measure the zeta potential and hydrodynamic size of the ND before and after modification with DGEA and DOX; samples were prepared at a concentration of 200 µg/mL. Cell culture Human bone metastatic prostate cancer cells (PC3) and mesenchymal stem cells (hMSC) were acquired from American

Cytotoxic and proinflammatory effects of PVP-coated silver nanoparticles after intratracheal instillation in rats

• Nadine Haberl,
• Stephanie Hirn,
• Alexander Wenk,
• Jörg Diendorf,
• Matthias Epple,
• Blair D. Johnston,
• Fritz Krombach,
• Wolfgang G. Kreyling and
• Carsten Schleh

Beilstein J. Nanotechnol. 2013, 4, 933–940, doi:10.3762/bjnano.4.105

• were not assessed in these studies. Several in vitro studies dealt with the mechanism of cytokine induction after AgNP exposure. Incubation of human mesenchymal stem cells and of peripheral blood monocytes with the same PVP-AgNP that were used in the present study induced a concentration-dependent

• the rate of the dissolution of AgNP depends on the surface functionalization, concentration and temperature [37]. They found an increasing toxicity to human mesenchymal stem cells during the storage of AgNP solutions, explained by the increasing release of silver ions over time. The authors emphasized