Laboratory for Energy Materials and Nano-Biomedicine
Design of Intelligent
Nanosystems to Address Critical Issues in Medical and Life Sciences
Search for New Mechanisms, Structures, and Properties in Advanced Energy Materials
The Laboratory for Energy Materials and Nano-Biomedicine investigates fundamental materials structures and properties for energy and biomedical applications.
For energy materials, the research focuses on developing novel structures, via design and thin film deposition, for unique physical properties in nano-photonics, dielectrics, and magnetics.
One of the NSF-funded projects deals with spectral-selective, photon-activated new structures for efficient energy materials.
Energy science has rapidly advanced in the past several decades, and mainly focused on efficient energy conversion, conservation, and storage via advanced technologies.
One critical issue deals with a large amount of thermal loss from public buildings. We developed, for the first time, making of a ”°Green Window”± by applying a natural chlorophyll thin film coating onto glass substrates.
Chlorophyll exhibits a unique optical characteristic with a saddle-like shape, i. e. with strong absorptions in the blue-violet and NIR regions while remaining highly transmissive in much of the visible region.
This unique property allows for efficient conversion of solar light to heat in the non-visible region, but permits high transmittance in the visible band, which is ideal for window applications.
This concept lifts the dependence on insulating materials for making single-pane windows.
Based on the photothermal heating by chlorophyll
coated glass substrates under white light, the heat loss is significantly reduced leading to U-factors well below those of single- or double- panes without photothermal coatings.
The novel concept presented in this study paves a new way for thermal insulation without insulating materials. The engineering implications show great promise in both energy and materials savings for sustainability.
Schematic of Chlorophyll-coated "Green Window"
Effective reduction of building heat loss without insulation materials via the photothermal effect of a chlorophyll thin ﬁlm coated ”°Green Window”±, Yuan Zhao, Andrew W. Dunn, and Donglu Shi
MRS Communications Volume 9, Issue 2 June 2019, pp. 675-681
Another project supported by The Ohio Federal Research develops soft magnetic alloys to provide a highly power dense magnetic core with low losses.
Research on soft magnetic materials has been focused extensively on the mechanisms by which magnetic properties change, as associated with variations in the ratio of the microstructural length scale (crystallite size) to the magnetic characteristic length scale (correlation length).
While the microstructures can be controlled through processing and compositional manipulation, the correlation length is governed by magnetic fluctuations in domains, that is magneto-crystalline anisotropy.
Nano-crystalline soft magnetic materials have been developed that share a common microstructural feature, having ferromagnetic nano-crystallites (~10 nm) embedded in an amorphous matrix,
which are considerably shorter than the correlation length,
resulting in a unique combination of large magnetization, high permeability, and low core loss.
We obtained the as-spun ribbon with a fraction of nano-crystallites embedded in the amorphous matrix directly from melt spinning (i.e. not through subsequent annealing).
Upon annealing and ball milling, we were able to control the microstructure of the fine powders in order to minimize coercivity in a wide temperature range.
The powder samples with nano-crystallites were found to be stable with enhanced the magnetic softness e.g., low Hc values at high temperatures.
Magnetization hysteresis curves for the Fe77Ni5.5Co5.5Zr7B4Cu powder sample measured at the temperatures indicated.
For Nano-Biomedicine, the research activities deal with design of nanostructures that enable successful cell targeting for tumor therapy, medical imaging by quantum dots, photothermal ablation of cancer cells, and drug/gene delivery by novel designs and intelligent triggering mechanisms.
The most recent works concentrate on pulmonary vascular disease that encompasses a wide range of serious afﬂictions with important clinical implications.
There is critical need for the development of efﬁcient, nonviral gene therapy delivery systems. A promising avenue to overcome critical issues in efﬁcient cell targeting within the lung via a uniquely designed nanosystem is reported.
Polyplexes are created by functionalizing hyperbranched polyethylenimine (PEI) with biological fatty acids and carboxylate-terminated poly(ethylene glycol) (PEG) through a one-pot 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride/N-hydroxysuccinimide reaction.
Following intravenous injection, polyplexes show an exceptionally high speciﬁcity to the pulmonary microvascular endothelium,
allowing for the successful delivery
of stabilized enhanced green ﬂuorescent protein (eGFP) expressing messenger ribonucleic acid (mRNA).
It is further shown, quantitatively, that positive surface charge is the main mechanism behind such high targeting efﬁciency for these polyplexes.
We demonstrated that positive polyplexes are enriched in the lung tissue and disseminated in 85–90% of the alveolar capillary endothelium, whilst being sparse in large vessels.
10x immunofluorescence of frozen lung sections post I.V. injection of DyLight 650 labeled PEI10k-LinA15-PEG3.0. Sections were stained with Hoechst 33342 (nuclear stain), platelet endothelial cell adhesion molecule (PECAM1, CD31),
and alpha smooth muscle actin („įSMA) for visualization of microvasculature and large vessels.
Highly Efficient In Vivo Targeting of the Pulmonary Endothelium Using Novel Modifications of Polyethylenimine: An Importance of Charge. Dunn, Andrew W., Vladimir V. Kalinichenko, Donglu Shi. Advanced healthcare materials, (2018): 1800876.
Nano Detection of Circulating Tumor Cells
Cancer cells may detach from the original tumor and enter lymphatic fluid and/or blood upon formation of malignant tumor.
These mobile cells are defined as circulating tumor cells (CTCs) and believed to be responsible for metastasis.
We have developed a novel approach that can sensitively detect CTCs from whole blood via nanotechnologies.
The concept is quite straightforward. It has been found that all cancer cells share a hallmark metabolic pattern:
high rate of glycolysis, resulting in a net of negative electrical charges on cancer cell surfaces.
The positively-charged Fe3O4 magnetic nanoparticles can electrostatically bind onto CTCs and magnetically separate them from physiological fluids.
Fig 1 shows the schematic diagram of CTC electrostatic capturing and magnetic separating process.
Fig. 2 shows the fluorescent image of cancer cell nuclei (blue) and surface electrostatically bound Fe3O4 nanoparticles (green).
Figure 1: CTC Capturing
Figure 2: Nanoparticle binding on cancer cells
Media reports on the novel Janus nanostructures that we have recently
developed for targeted drug delivery:
The American Ceramic Society