Publication: Nanomaterials. 2022 Mar 11;12(6):929. Publication Date: March 11, 2022.

Abstract:
Gold nanorods (AuNRs) have been proposed to promote stem cell differentiation in vitro and in vivo. In this study, we examined a particular type of AuNR in supporting the differentiation of rat fetal neural stem cells (NSCs) into oligodendrocytes (ODCs). AuNRs were synthesized according to the seed-mediated method resulting in nanorods with an aspect ratio of around 3 (~12 nm diameter, 36 nm length) and plasmon resonance at 520 and 780 nm, as confirmed by transmission electron microscopy (TEM) and UV-vis spectroscopy, respectively. A layer-by-layer approach was used to fabricate the AuNR substrate on the functionalized glass coverslips. NSCs were propagated for 10 days using fibroblast growth factor, platelet-derived growth-factor-supplemented culture media, and differentiated on an AuNR or poly-D-lysine (PDL)-coated surface using differentiation media containing triiodothyronine for three weeks. Results showed that NSCs survived better and differentiated faster on the AuNRs compared to the PDL surface. By week 1, almost all cells had differentiated on the AuNR substrate, whereas only ~60% differentiated on the PDL surface, with similar percentages of ODCs and astrocytes. This study indicates that functionalized AuNR substrate does promote NSC differentiation and could be a viable tool for tissue engineering to support the differentiation of stem cells.

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Publication: Nanomaterials. 2022 Mar 12;12(6):937. Publication Date: March 12, 2022.

Abstract:

Nanosized materials have been proposed for a wide range of biomedical applications, given their unique characteristics. However, how these nanomaterials interact with cells and tissues, as well as how they bio-distribute in organisms, is still under investigation. Differences such as the nanoparticle size, shape, and surface chemistry affect the basic mechanisms of cellular uptake and responses, which, in turn, affects the nanoparticles’ applicability for biomedical applications. Thus, it is vital to determine how a specific nanoparticle interacts with cells of interest before extensive in vivo applications are performed. Here, we delineate the uptake mechanism and localization of gold nanorods in SKBR-3 and MCF-7 breast cancer cell lines. Our results show both differences and similarities in the nanorod-cell interactions of the two cell lines. We accurately quantified the cellular uptake of gold nanorods in SKBR-3 and MCF-7 using inductively coupled plasma mass spectrometry (ICP-MS). We found that both cell types use macropinocytosis to internalize bare nanorods that aggregate and associate with the cell membrane. In addition, we were able to qualitatively track and show intracellular nanoparticle localization using transmission electron microscopy. The results of this study will be invaluable for the successful development of novel and “smart” nanodrugs based on gold nano-structural delivery vehicles, which heavily depend on their complex interactions with single cells.

The post Cellular Uptake of Gold Nanorods in Breast Cancer Cell Lines appeared first on Center for Integrative Nanotechnology Sciences.

Publication: Scientific Reports. 12, Article number: 3208 (2022) Publication Date: February 25, 2022

Abstract:
The aim of this study was to create a surgical guide platform that maintains its integrity while the surgeon performs an intestinal anastomosis or another similar procedure, which then breaks apart and is eliminated from the body in a controlled manner. The device contains mixed polymeric structures that give it a controlled rate of disassembly that could meet the requirements of a specific surgical purpose. The intraluminal anastomotic guide was manufactured as a hollow cylinder composed of layers of porous polyurethane/PCL with polyvinylpyrrolidone as the binding agent similar to a “brick–mortar” architecture. This combination of polymeric structures is a promising manufacturing method from which a variety of tunable devices can be fabricated for specific medical procedures and site-specific indications. The guide was designed to rapidly disassemble within the intestinal lumen after use, reliably degrading while maintaining sufficient mechanical rigidity and stability to support manipulation during complex surgical procedures. The nature of the device’s disassembly makes it suitable for use in hollow structures that discharge their contents, resulting in their elimination from the body. A swine model of intestinal anastomosis was utilized to validate the use and function of the device.

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Publication: ACS Appl. Energy Mater. 2021, XXXX, XXX, XXX-XXX, Publication Date: March 22, 2021.

Abstract: Cesium formadinium methylammonium triple-cation (CsFAMA) lead mixed-halide perovskites have been reported to promote unique photovoltaic properties with high efficiency and minimal hysteresis effects. Perovskite film quality is a vital parameter for improving the performance of perovskite solar cells (PSCs). Here, we report the growth of CsFAMA perovskites with microscale grains passivation grain boundaries by mixing HC(NH₂)₂I (FAI) and CH₃NH₃Br (MABr) in isopropanol (IPA) as a post-treatment step to cause controlled Ostwald ripening, leading to secondary grain growth. Compared to the conventional preparation of perovskite films with a free organic halide antisolvent, this mixed-cation mixed-halide post-treatment created higher quality perovskite films in terms of morphology, electronic properties, energy level alignment, and carrier recombination, with the band gap adjusted at the optimal concentration. Treatment with the single cation and single halide presented by FAI and/or MABr in IPA treatment was also investigated, and the results showed that multiple band gap perovskite structures were obtained, which could be beneficial for band gap engineering. This method of perovskite preparation was tested in an inverted planar configuration with a hole transport layer (HTL) based on sulfonated poly(thiophene-3-[2-(2-methoxy-ethoxy)ethoxy]-2,5-diyl) (SP3MEET). The efficiency of the PSCs was dramatically boosted from 13.80% with the organic halide-free antisolvent to 17.62% when the mixed-cation mixed-halide approach was used. In addition, the PSCs treated with the mixed-cation mixed-halide solution exhibited excellent reproducibility, with a high fill factor and eliminated hysteresis. The CsFAMA photovoltaic device based on the single organic cation and single halide treatment approach showed power conversion efficiency of 15.82 and 15.90% for the FAI and MABr-treated films, respectively. Characterization of the S-P3MEET as HTLs found that good optoelectronic and morphological properties lead to improve the performance of the inverted PSC. However, with further research to align the energy levels at the S-P3MEET/perovskite interface, greater improvements in the PSCs are expected.

The post Surface Passivation of Triple-Cation Perovskite via Organic Halide-Saturated Antisolvent for Inverted Planar Solar Cells appeared first on Center for Integrative Nanotechnology Sciences.

Publication: J Appl Toxicol. 2021 Jan 8. doi: 10.1002/jat.4136. Epub ahead of print. PMID: 33417269.

Abstract: The use of synthetic materials for biomedical applications is ever expanding. One of the major requirements for these materials is biocompatibility, which includes prevention of immune system responses. Due to the inherent complexity of their structural composition, the polyurethane (PU) family of polymers is being used in a variety of medical applications, from soft and hard tissue scaffolds to intricate coatings on implantable devices. Herein, we investigated whether two polymer materials, D3 and D7, induced an immune response, measured by their effects on a dendritic cell (DC) line, JAWS II. Using a lactate dehydrogenase cytotoxicity assay and Annexin V/PI staining, we found that the PU materials did not induce cytotoxicity in DC cells. Using confocal microscopy, we also showed that the materials did not induce activation or maturation, as compared to positive controls. This was confirmed by looking at various markers, CD80, CD86, MHC class I, and MHC class II, via flow cytometry. Overall, the results indicated that the investigated PU films are biocompatible in terms of immunotoxicology and immunogenicity and show great promise for use in regenerative medicine.

The post Dendritic cell biocompatibility of ether-based urethane films appeared first on Center for Integrative Nanotechnology Sciences.

The University of Arkansas at Little Rock has received state and federal approval to award a services contract to NuShores Biosciences LLC for Generation 1 manufacturing of the NuCress bone void filler scaffold products. This contract is funded by a $5.6 million grant awarded by the Department of Defense to ĚÇĐÄVlog´«Ă˝ Little Rock in 2019. Read more…

The post MILITARY MEDICAL SPONSORS AWARD MANUFACTURING DEVELOPMENT CONTRACT TO NUSHORES BIOSCIENCES appeared first on Center for Integrative Nanotechnology Sciences.

Publication: PLoS One. 2020;15(5):e0232670. Published 2020 May 18. doi:10.1371/journal.pone.0232670

Abstract: Complex skin wounds have always been a significant health and economic problem worldwide due to their elusive and sometimes poor or non-healing conditions. If not well-treated,
such wounds may lead to amputation, infections, cancer, or even death. Thus, there is a need to efficiently generate multifunctional skin grafts that address a wide range of skin conditions, including non-healing wounds, and enable the regeneration of new skin tissue. Here, we propose studying pristine graphene and two of its oxygen-functionalized derivatives—high and low-oxygen graphene films—as potential substrates for skin cell proliferation and differentiation. Using BJ cells (human foreskin-derived fibroblasts) to represent basic skin cells, we show that the changes in surface properties of pristine graphene due to oxygen functionalization do not seem to statistically impact the normal proliferation and maturation of skin cells. Our results indicate that the pristine and oxidized graphenes presented relatively low cytotoxicity to BJ fibroblasts and, in fact, support their growth and bioactivity. Therefore, these graphene films could potentially be integrated into more complex skin regenerative systems to support skin regeneration. Because graphene’s surface can be relatively easily functionalized with various chemical groups, this finding presents a major opportunity for the development of various composite materials that can act as active components in regenerative applications such as skin regeneration.

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Publication:  Int J Nanomedicine. 2020;15:2501-2513. Published 2020 Apr 15. doi:10.2147/IJN.S245801

Abstract:

Purpose: The extracellular matrix (ECM) labyrinthine network secreted by mesenchymal stem cells (MSCs) provides a microenvironment that enhances cell adherence, proliferation, viability, and differentiation. The potential of graphene-based nanomaterials to mimic a tissue-specific ECM has been recognized in designing bone tissue engineering scaffolds. In this study, we investigated the expression of specific ECM proteins when human fat-derived adult MSCs adhered and underwent osteogenic differentiation in the presence of functionalized graphene nanoparticles.

Methods: Graphene nanoparticles with 6-10% oxygen content were prepared and characterized by XPS, FTIR, AFM and Raman spectroscopy. Calcein-am and crystal violet staining were performed to evaluate viability and proliferation of human fat-derived MSCs on graphene nanoparticles. Alizarin red staining and quantitation were used to determine the effect of graphene nanoparticles on osteogenic differentiation. Finally, immunofluorescence assays were used to investigate the expression of ECM proteins during cell adhesion and osteogenic differentiation.

Results: Our data show that in the presence of graphene, MSCs express specific integrin heterodimers and exhibit a distinct pattern of the corresponding bone-specific ECM proteins, primarily fibronectin, collagen I and vitronectin. Furthermore, MSCs undergo osteogenic differentiation spontaneously without any chemical induction, suggesting that the physicochemical properties of graphene nanoparticles might trigger the expression of bone-specific ECM.

Conclusion: Understanding the cell-graphene interactions resulting in an osteogenic niche for MSCs will significantly improve the application of graphene nanoparticles in bone repair and regeneration.

The post Functionalized Graphene Nanoparticles Induce Human Mesenchymal Stem Cells to Express Distinct Extracellular Matrix Proteins Mediating Osteogenesis appeared first on Center for Integrative Nanotechnology Sciences.

Publication: Scientific Reports, Volume 10, Issue 1, 2020

Abstract: Pancreatic cancer is one of the most complex types of cancers to detect, diagnose, and treat. However, the field of nanomedicine has strong potential to address such challenges. When evaluating the diffusion and penetration of theranostic nanoparticles, the extracellular matrix (ECM) is of crucial importance because it acts as a barrier to the tumor microenvironment. In the present study, the penetration of functionalized, fluorescent gold nanorods into large (>500 ÎĽm) multicellular 3D tissue spheroids was studied using a multimodal imaging approach. The spheroids were generated by co-culturing pancreatic cancer cells and pancreatic stellate cells in multiple ratios to mimic variable tumor-stromal compositions and to investigate nanoparticle penetration. Fluorescence live imaging, photothermal, and photoacoustic analysis were utilized to examine nanoparticle behavior in the spheroids. Uniquely, the nanorods are intrinsically photoacoustic and photothermal, enabling multi-imaging detection even when fluorescence tracking is not possible or ideal.

The post Tracking gold nanorods’ interaction with large 3D pancreatic-stromal tumor spheroids by multimodal imaging: Fluorescence, photoacoustic, and photothermal microscopies appeared first on Center for Integrative Nanotechnology Sciences.

Publication: BioResearch Open Access, Volume 9, Issue 1, 2020

Abstract: Effective graft technologies for bone repair have been a primary focus in the field of bone tissue engineering. We have previously fabricated and examined a nanocomposite composed of polyurethane, nano-hydroxyapatite, and decellularized bone particles, which demonstrated osteobiologic characteristics. To evaluate the underlying mechanisms of this biomaterial, human adipose-derived mesenchymal stem cell seeded scaffolds were assessed using a combinatorial approach of transcriptomic and metabolomic analyses. Data from osteogenic and signal transduction polymerase chain reaction arrays and small molecule abundances, measured through liquid chromatography–mass spectrometry, were cross-examined using Integrated Molecular Pathway Level Analysis, Database for Annotation, Visualization, and Integrated Discovery, and ConsensusPathDB online tools to generate a fundamental collection of scaffold-influenced pathways. Results demonstrated upregulation of key osteogenic, cellular adhesion cell signaling markers and indicated that Hedgehog and Wnt signaling pathways were primary candidates for the osteobiologic mechanisms of the scaffold design. The detection of complimentary metabolites, such as ascorbate, further indicates that scaffolds generate intricate cellular environments, promoting cell attachment and subsequent osteodifferentiation.

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