Core-shell Ratio Research Articles

Avermectin/polyacrylate nanoparticles: preparation, characterization, anti-UV and sustained release properties

In an effort to reduce the dose of drugs and in order to improve drug efficacy, avermectin (AVM) was encapsulated by amphipathic polyacrylic ester (PAE) via self-assembly. The experimental results indicated that the AVM/PAE nanoparticles were spherical in shape, homogeneous dispersion, and had a core-shell structure, the particle size ranged from 172.7 nm to 337.8 nm, the highest encapsulation efficiency and loading capacity were 62.11 and 25.65%. The anti-UV property has been significantly improved. Consistent with the Korsmeyer–Peppas model, the release rate was observed to be higher upon decreasing Tg and increasing the core-shell ratio.

Core-shell nanospheres to achieve ultralow friction polymer nanocomposites with superior mechanical properties.

Core-shell nanospheres have been widely used in catalysis, batteries, medicine, etc. owing to their unique structural characteristics, which exhibit optimal performance and integrated functions of both the core and shell materials. To simultaneously achieve outstanding mechanical properties and remarkable lubrication properties in desirable polymer composites, core-shell nanospheres with polytetrafluoroethylene (PTFE) as the core and poly methyl methacrylate (PMMA) as the shell have been adopted as structural units to form bulk nanocomposites. We demonstrated that the mechanical and lubrication properties of the nanocomposites prepared using core-shell nanospheres as the continuous matrix were dramatically improved. Specifically, when compared with that of pure PTFE, the compressive strength of the PTFE@PMMA nanocomposite obviously increased up to one order of magnitude (from ∼9 to ∼90 MPa), the friction coefficient reduced to 25% (the lowest value was 0.03), and the wear rate decreased up to two orders of magnitude. Moreover, the mechanical and lubrication properties of the nanocomposites could be adjusted by changing the core-shell ratio, and an appropriate core-shell ratio was beneficial for achieving the desired comprehensive properties. It has been proposed that the properties, such as the confinement effect, improved dispersion capacity, etc., imparted by the core-shell structure effectively lead to high dispersion of the reinforcement phase, improvement of the binding force of the transfer film to the friction surface, and interruption of the wear process of the polymer composite.

Time evolution of steep diffusion fronts in highly viscous aerosol particles measured with Mie resonance spectroscopy.

Field and laboratory measurements indicate that atmospheric organic aerosol particles can be present in a highly viscous state. In contrast to liquid state particles, the gas phase equilibration to ambient relative humidity (RH) can be kinetically limited and governed by condensed phase diffusion. In water diffusion experiments on highly viscous single aerosol particles levitated in an electrodynamic balance, we observed a characteristic shift behavior of the Mie scattering resonances indicative of the changing radial structure of the particle, thus providing an experimental method to track the diffusion process inside the particle. Due to the plasticizing effect of water, theory predicts extremely steep, front-like water concentration gradients inside highly viscous particles exposed to a rapid increase in RH. The resulting quasi step-like concentration profile motivates the use of a simple core-shell model describing the morphology of the non-equilibrium particle during humidification. The particle growth and reduction of the shell refractive index can be observed experimentally as redshift and blueshift behavior of the Mie resonances, respectively. We can deduce the particle radius as well as a core-shell radius ratio from the measured shift pattern and Mie scattering calculations. Using both the growth information obtained from the Mie resonance redshift and thermodynamic equilibrium data, we can infer a comprehensive picture of the time evolution of the diffusion fronts in the framework of our core-shell model. The observed shift behavior of the Mie resonances provides direct evidence of very steep diffusion fronts caused by the plasticizing effect of water and a method to validate previous diffusivity measurements.

Quantifying and Comparing the Near-Field Enhancement, Photothermal Conversion, and Local Heating Performance of Plasmonic SiO2@Au Core-Shell Nanoparticles

In this work, the finite element method and two-temperature model were used to optimize the near electric field, photothermal conversion efficiency, and local heating of SiO2@Au core-shell nanoparticles (NPs) using water as the dispersion medium. The optimal core-shell sizes to achieve maximum near electric field enhancement, photothermal conversion efficiency, and local heating were 14 nm/6 nm, 8 nm/3 nm, and 24 nm/12 nm. The optimized core-shell ratio decreased with increasing the optimized wavelength for both near electric field and photothermal conversion optimizations. In the local heating or temperature increase, due to the existence of thermal boundary conductance, a temperature drop was observed between the electrons and the lattice, the electrons and the dielectrics, and the NP and the surrounding water. All these barriers and high absorption ability led to a temperature increase in the NP region. All optimized core-shell NPs achieved surface plasmon resonance for different targets. Comparison between different optimized targets with a normalized processing function indicated a smaller optimized core-shell size and core-shell ratio were obtained with a consideration of greater effect of the NP radius.

Preparation and application of low-temperature-curable, alkylphenol ethoxylate-free, and flame-retardant flocking adhesive

In this study, a low temperature-curable and alkylphenol ethoxylate-free acrylic emulsion was synthesized with diacetone acrylamide (DAAM) and adipic dihydrazide (ADH) as a crosslinking system; butyl acrylate (BA), ethyl acrylate (EA), methyl methacrylate (MMA), and acrylic acid (AA) as monomers; vinyl siloxane as a modifier; sodium-dodecyl sulphate (SDS) and AEO-9 as a compound emulsifier by means of semicontinuous emulsion polymerization. The optimal polymerization conditions by weight proportion determined by the orthogonal experiments were emulsifier amount, 4%, initiator amount, 0.5%, DAAM amount, 2.5%, and core–shell ratio, 3/2. Three flame-retardant additives, namely, ammonium polyphosphate (APP), FR-5, and organic montmorillonite, were mixed with the acrylic emulsion to synthesize the flocking adhesive SA. The char length, afterglow time, and afterflame time of the flocking fabrics were characterized to evaluate the fire-retardant properties of the adhesives. The results clearly evidence an outstanding improvement in fire-retardant properties using adhesive SA based on good flocking fastness and fabric handle.

Core-Shell Morphology of Redispersible Powders in Polymer-Cement Waterproof Mortars.

Redispersible powders based on soft core-hard shell polymer particles can be used as additives in polymer-cement mortars. The role of this morphology on the spray-drying production of these powders and on the crack-bridging properties of the corresponding cement-based membranes is investigated. Different polymer latexes at high solid content with varied core-shell ratio, shell thickness and chemical composition (hardness) were prepared from styrene and 2-ethylhexyl acrylate monomers via semi-batch emulsion polymerization. The latexes were characterized in terms of size, composition, and glass transition temperature (T), and spray-dried to obtain redispersible polymer powders (RPPs) using poly (vinyl alcohol) and limestone powder as anti-caking agents. The polymer powders were mixed with a mortar mixture and redispersed in water to produce cement-based membranes, which were tested for crack-bridging properties at different temperatures. The results showed that it was not possible to spray-dry a dispersion of homogeneous polymer particles with T of −25 C, unless these particles are protected by much harder (high T) shell. In particular, it was observed that a thicker shell improved the spray-ability, but lowered the crack-bridging properties of the produced membrane. A trade-off between these two was revealed to be the key for the optimal design of the polymer nanoparticles, as proven by the systematic study of the core-shell morphology reported in this work. The best compromise was shown to consist of particles larger than 300 nm, shell thickness of about 5 nm, and core-shell ratio of 97%, with styrene content in the shell not larger than 80% to avoid excessive hydrophobicity.

The influence of emulsifiers on preparation and properties of microencapsules of melamine–urea–formaldehyde resins with n‐dodecanol as phase‐change material

AbstractMelamine–urea–formaldehyde resins/n‐dodecanol microencapsulated phase‐change materials (microPCMs) were prepared by in situ polymerization method in this work. In the microPCMs, the n‐dodecanol was used as phase‐change material (PCM) for thermal energy storage, and the melamine–urea–formaldehyde resins (MUF) acted as shell materials. The Fourier‐transform infrared spectroscopy (FT‐IR) indicated that the PCM n‐dodecanol is encapsulated in the MUF shell controlling pH of n‐dodecanol emulsion at 4.5, and there is no chemical reaction between them. The thermal properties of the microcapsules were measured by differential scanning calorimeter (DSC). The morphology and particle size of the microPCMs were surveyed by scanning electron microscopy (SEM) and laser particle diameter analyzer. The results showed that styrene‐maleic anhydride copolymer (SMA) anionic emulsifier is suitable for the preparation of MUF microPCMs. The cooling and melting phase‐change enthalpy were 130.5 and 135.2 J/g, and the cooling and melting phase‐change temperature were 20.9 and 19.11°C when core–shell ratio reached 3:1. In addition, increasing amount of SMA can enhance the phase‐change enthalpy.

Effective Dielectric Constant of Plasmonic Nanofluid Containing Core-Shell Nanoparticles

This paper focuses on the effective dielectric constant of water-based plasmonic nanofluid containing SiO2/Ag core/shell nanoparticles (NPs). Two effective models, based on S-parameter retrieval method and Maxwell-Garnett effective medium theory, are employed. The effective dielectric constants predicted by the two effective models are compared and the applicability is evaluated by comparing the reflectance and absorptance. Three influence factors, including volume fraction, core-shell ratio, and size of NPs, are considered. Results show both of the two effective models can predict reliable effective dielectric constants when the volume fraction, size, and core-shell ratio of nanoparticles are 5%, 25 nm, and 4:1 respectively. Only small deviations appear in the resonant region under this condition. With the increase of volume fraction, shell proportion, or size, deviations in the resonant region become larger for both of the two effective models. Therefore, the predicted effective dielectric constants are not suitable for the prediction of optical properties, because the resonant region is the key region of the solar conversion for plasmonic nanofluids. Hence, the parameters of NPs need to be changed to make the effective models applicable. Moreover, the effective model based on S-parameter retrieval can predict more reliable dielectric constant than the effective model based on Maxwell-Garnett theory.

Computational modeling of fracture in encapsulation-based self-healing concrete using cohesive elements

Fracture behavior of encapsulation-based self-healing concrete (SHC) is investigated numerically. In this paper, we study the influence of capsules including its volume ratio and core-shell thickness on the load carrying capacity and fracture likelihood of the capsules. In order to randomly create the mesoscale structure of self-healing concrete, an efficient packing algorithm is employed. For a given number of circular capsules with particular diameter and shell thickness, the aggregates are generated from prescribed distributions of their size and volume fraction. The capsules are made of Poly Methyl Methacrylate and potential cracks are represented by pre-inserted cohesive elements with tension and shear softening laws along all element boundaries including the interfaces between different phases. The effects of the volume fraction of capsules and core-shell thickness ratio on the load carrying capacity and fracture probability of the capsules are analyzed. It is found that the load-carrying capacity of self-healing concrete decreases as the capsules volume fraction increases. The capsule core-shell thickness ratio has no significant influence on the specimen strength but a very significant impact on the breakage of capsule shell. Given a fixed volume fraction of capsules, the higher core-shell thickness ratio, the higher is the number of capsules which fracture. Assuming the core-shell ratio thickness is fixed, increasing the volume fraction of capsules will increase the probability of capsules which break.

The effects of interfacial strength on fractured microcapsule

The effects of interfacial strength on fractured microcapsule are investigated numerically. The interaction between crack and microcapsule embedded in mortar matrix is modeled based on cohesive approach. The microcapsules are modelled with variation of core-shell thickness ratio and potential cracks are represented by pre-inserted cohesive elements along the element boundaries of the mortar matrix, microcapsules core, microcapsule shell, and at the interfaces between these phases. Special attention is given to the effects of cohesive fracture on the microcapsule interface, namely fracture strength, on the load carrying capacity and fracture probability of the microcapsule. The effect of fracture properties on microcapsule is found to be significant factor on the load carrying capacity and crack propagation characteristics. Regardless of core-shell thickness ratio of microcapsule, the load carrying capacity of self-healing material under tension increases as interfacial strength of microcapsule shell increases. In addition, given the fixed fracture strength of the interface of microcapsule shell, the higher the ratio core-shell thickness, the higher the probability of microcapsules being fractured.

Effects and mechanisms of surface-treatment of cementitious materials with nanoSiO2@PCE core-shell nanoparticles

A commercial interest in the improvement of durability is driving efforts to develop new generation of surface-treatment agents. In the previous paper, a series of nanoSiO2-polycarboxylate superplasticizer core-shell nanoparticles (NS@PCE) were synthesized by “grafting to” method. In this paper, we aim to explore the potential of NS@PCE to densify the surface of cementitious materials, and to study the mechanism of nanoparticles surface-treatment process by measuring water absorption ratio, dispersion stability, pozzolanic reactivity, and mercury intrusion porosimetry. Results show that NS@PCE is effective in reducing the water absorption. Various NS@PCE present different influences, it seems that NS@PCE with a moderate shell-core ratio is a more reasonable choice. A hypothesis was proposed to explain the surface-treatment effect of nanoparticles, it utilizes two properties (dispersity and pozzolanic reactivity) of nanoparticles to describe their refining-pore performance. This research indicates a new pathway for nanoSiO2 to optimizing cementitious materials.

Theoretical analysis of bimetallic nanorod dimer biosensors for label-free molecule detection

In this work, we theoretically analyze a gold (Au) core within silver (Ag) shell (Au@Ag) nanorod dimer biosensor for label-free molecule detection. The incident light on an Au@Ag nanorod strongly couples to localized surface plasmon modes, especially around the tip region. The field enhancement around the tip of a nanorod or between the tips of two longitudinally aligned nanorods as in a dimer can be exploited for sensitive detection of biomolecules. We derive analytical expressions for the interactions of an Au@Ag nanorod dimer with the incident light. We also study the detail dynamics of an Au@Ag nanorod dimer with the incident light computationally using finite difference time domain (FDTD) technique when core-shell ratio, relative position of the nanorods, and angle of incidence of light change. We find that the results obtained using the developed analytical model match well with that obtained using FDTD simulations. Additionally, we investigate the sensitivity of the Au@Ag nanorod dimer, i.e., shift in the resonance wavelength, when a target biomolecule such as lysozyme (Lys), human serum albumin (HSA), anti-biotin (Abn), human catalase (CAT), and human fibrinogen (Fb) protein molecules are attached to the tips of the nanorods.

Photothermal properties of core-capped gold nanoparticles

Photothermal effects associated with noble metal nanostructures have shown wide potential applications in photo-thermal cancer therapy, photo-thermal imaging, nanomedicine, etc. These applications benefit from the localized surface plasmon resonance (LSPR) effect of the nanoparticles. Due to the LSPR effect, the nanoparticles exhibit unique optical properties such as strong scattering and absorption in the band ranging from visible to near-infrared region. The absorption enables the plasmonic nanoparticle to be a thermal source to increase the temperature of itself and the localized surrounding environment. Among these particels, the anisotropic core-capped nanostructures distinguish themselves by their strong polarization selectivity. The absorptions are different when the incident light is polarized in the directions vertical (90) and parallel (0) to its symmetry axis, respectively. At 90, a large red-shift can be achieved and the absorption cross section is greatly enhanced. Moreover, their absorption peaks can be flexibly manipulated by slightly adjusting one of the geometrical parameters. However, the photothermal responses to these parameters are left blank. In this paper, photothermal effects of SiO2@Au core-capped nanoparticles are studied based on the numerical finite elemental analysis method (COMSOL software). The thermal response to each of the paramenters, including shell thickness, core diameter, core-shell ratio, and metal surface coverage is achieved. The calculation shows that the temperature of these core-capped nanoparticles can be adjusted efficiently in the near infrared band by easily rotating the polarization, i.e. slightly adjusting the geometric parameters. Especially in a range between 30 and 70, the temperature varying with the polarization follows almost a linear relationship. The comparisons with other popular structures including solid sphere, core-shell and nanorod are also made. The results indicate that at a similar size, the core-capped structure can offer a higher temperature than solid spheres and core-shell structures. To obtain the same temperature variation, the core-capped one has a smaller size than a nanorod. The comparisons demonstrate that the core-capped structure can be an alternative to a high-efficient nano heat source in the photothemal applications.

Complementary enhanced solar thermal conversion performance of core-shell nanoparticles

In this study, the properties of various types of core-shell nanoparticles (NPs) were evaluated using the finite difference time domain (FDTD) method towards the enhancement of solar absorption performance. Results showed that the resonance wavelength of SiO2@Au NPs lay in the 540–900 nm range, covering the near-infrared and visible regions. The resonance wavelength of SiO2@Ag NPs lay in the 390–830 nm range, covering the entire visible region. SiO2@Au nanofluid with a core-shell ratio of φ = 0.2 exhibited the highest solar absorption efficiency with 64% less Au consumption compared to pure Au NPs. For mixed nanofluids, the mixtures featuring core-shell ratios of 0.1 and 0.6 with mixing ratios of 0.5 for SiO2@Au and 0.6 for SiO2@Ag gave the highest absorption efficiencies. In addition, the peak solar absorption efficiency of a mixed nanofluid of SiO2@Au (φ = 0.1) and SiO2@Ag (φ = 0.4) with a mixing ratio of 0.58 was as high as 94.4%. Solar thermal conversion experiments revealed that, under the same conditions, a Au-decorated SiO2 nanofluid showed a comparable efficiency to the calculated solar absorption efficiency of the SiO2@Au core-shell nanofluid (∼95.2%); it was as high as 95.9%, higher than those of Au NPs and SiO2 NPs. These results showed that adjusting the core-shell ratios and tuning the mixing ratios of different nanofluids are two efficient methods to enhance the solar absorption efficiencies of SiO2@Au and SiO2@Ag NPs under the optimal conditions.

Absorption enhancement of aged black carbon aerosols affected by their microphysics: A numerical investigation

An idealized spherical model with black carbon (BC) aggregates fully coated by sulfate is developed to study the absorption enhancement (Eab) of polydisperse BC aerosols, which is numerically calculated by the multiple-sphere T-matrix method (MSTM). The aim of this study is to evaluate the effects of aerosol microphysics on the absorption enhancement of fully coated BC particles. The Eab values of accumulation concentric coated BC aggregates with different BC fractal dimensions vary within 2%, while those of coarse coated BC aggregates can alter up to 20% depending on shell-core ratio Dp/Dc (spherical equivalent particle diameter divided by BC core diameter). The BC position inside coating can result in an Eab decrease of fully coated BC aggregates up to approximately 15% and 20% in the accumulation and coarse modes, respectively. Compared with the concentric spherical structure, the off-center coated BC aggregates shows similar Eab with a difference less than 9% in the accumulation mode, whereas it can lead to up to 31% reductions in Eab in the coarse mode. The absorption enhancement of aged BC is sensitive to particle size distribution, and it decreases as particles becomes larger in accumulation mode, whereas the reverse is true in coarse mode. For BC aggregates fully coated with a very thin layer sulfate at different size distributions, Eab values are generally in ranges of 1.5–1.8 and 1.3–1.4 in accumulation and coarse modes, respectively, while with coating reaching Dp/Dc = 2.7, their values range from 1.7–2.4 and 2.0–2.1 in accumulation and coarse modes, respectively. Our study indicates that, larger Dp/Dc with BC aggregates not close to the coating boundary, or BC position closer to particle geometric center enhance BC lensing effect, whereas BC aggregates near the boundary of heavy coating may not further enhance lensing effect significantly with increased coating fraction.

Solvent Induced Inversion of Core-Shell Microgels.

The morphology of core-shell microgels under different swelling conditions and as a function of the core-shell thickness ratio is systematically characterized by mesoscale hydrodynamic simulations. With increasing hydrophobic interaction of the shell polymers, we observe drastic morphological changes from a core-shell structure to an inverted microgel, where the core is turned to the outside, or a microgel with a patchy surface of core polymers directly exposed to the environment. We establish a phase diagram of the various morphologies. Moreover, we characterize the polymer and microgel conformations. For sufficiently thick shells, the changes of the shell size upon increasing hydrophobic interactions are well described by the Flory-Rehner theory. Additionally, this theory provides a critical line in the phase diagram separating core-shell structures from the distinct two other phases. The appearing new phases provide a novel route to nano- and microscale functionalized materials.

Simulations of the Surface Plasmon Resonances of Au@Ag Core-Shell Nanocubes: Effect of Core-Shell Size Ratio

This paper reports a systematic investigation on the optical properties of Au@Ag core-shell nanocubes as a function of the core-shell size ratio with the boundary element method (BEM).The absorption cross sections (nm2) for different light wavelengths are calculated using the full Maxwell equations. Also, the related field enhancements for Au@Ag core-shell nanocubes with an incoming plane wave with a polarization along the x-axis are computed. The surface charge at the resonance wavelength of 400 nm and then the electric fields outside and inside the core-shell nanocubes are mapped. A comparison of plasmonic modes between Au@Ag core-shell and single Ag nanocubes shows that there are minor differences between their responses where the surface plasmonic resonance peak position remains constant with varying the core-shell nanocubes ratio up to 50% in most cases under consideration. However, the maximum values of absorption cross sections increase with increasing the core-shell sizes ratio up to core-shell size ratio equal to 50%. The core-shell size ratio dependence of optical properties described here can be utilized in designing plasmonic nanostructures for applications in biosensors, nonlinear spectroscopy, near-field lithography and plasmonic solar cells.

Physicochemical and biological characteristics of BMP-2/IGF-1-loaded three-dimensional coaxial electrospun fibrous membranes for bone defect repair.

Coaxial electrospun fibrous membranes show favorable mechanical properties for use in guided bone regeneration (GBR). We used coaxial electrospinning technology to fabricate three-dimensional nanofiber membranes loaded with BMP-2 and IGF-1, and assessed the physicochemical and biological properties of these novel membranes in vitro. We fabricated four experimental groups of BMP-2/IGF-1/BSA-loaded membranes with different flow ratios (shell/core). Membrane characteristics were assessed by scanning and transmission electron microscopy, and laser confocal microscopy. Physicochemical and drug release properties were evaluated based on contact angle, mechanical property testing, X-ray diffraction analysis, and ELISA. The membranes were seeded with bone marrow-derived mesenchymal stem cells (BMMSCs) to estimate their biological properties based on cell viability and alkaline phosphatase (ALP) activity. The four membrane groups presented uniform diameters and core-shell structures. Acceleration of the shell solution flow rate increased the contact angle and mechanical properties of the fibrous membrane, while dual-factor addition did not impact fiber structure. Each drug-loaded membrane showed a gradually increasing release curve, with varying degrees of burst and sustained release. Compared to the other groups, the membranes with a core-shell flow ratio of 1:10 showed better drug-loading capacity and sustained release performance, higher biological properties and good barrier function. Optimal parameters were chosen based on the physical and chemical characteristics and biological properties of the membrane. Our results imply that the BMP-2/IGF-1/BSA-loaded coaxial electrospun fibrous membrane with optimum parameters is a suitable barrier membrane for GBR, and releases multiple factors promoting osteoconduction and osteoinduction.

Interface formation energy, bonding, energy band alignment in α-NaYF4 related core shell models: For future multi-layer core shell luminescence materials

To break through the bottle-neck of quantum yield in upconversion (UC) core-shell system, we elucidated that the energy transfer efficiency in core-shell system had an evident contribution from the charge transfer of interface with related to two factors: (1) band offsets and (2) binding energy area density. These two variables were determined by material intrinsic properties and core-shell thickness ratio. We further unraveled the mechanism of non-radiative energy transfer by charge transfer induced dipole at the interface, based on a quasi-classical derivation from Förster type resonant energy transfer (FRET) model. With stable bonding across the interface, the contributions on energy transfer in both radiative and non-radiative energy transfer should also be accounted together in Auzel's energy transfer (ETU) model in core-shell system. Based on the discussion about interface bonding, band offsets, and formation energies, we figured out the significance of interface bonding induced gap states (IBIGS) that played a significant role for influencing the charge transfer and radiative type energy transfer. The interface band offsets were a key factor in dominating the non-radiative energy transfer, which was also correlated to core-shell thickness ratio. We found that the energy area density with related to core/shell thickness ratio followed the trend of Boltzman sigmoidal growth function. By the physical trend, this work contributed a reference how the multi-layered core-shell structure was formed starting from the very beginning within minimum size. A route was paved towards a systematic study of the interface to unveil the energy transfer mechanism in core-shell systems.

Association between tumor architecture derived from generalized Q-space MRI and survival in glioblastoma.

While it is recognized that the overall resistance of glioblastoma to treatment may be related to intra-tumor patterns of structural heterogeneity, imaging methods to assess such patterns remain rudimentary. Methods: We utilized a generalized Q-space imaging (GQI) algorithm to analyze magnetic resonance imaging (MRI) derived from a rodent model of glioblastoma and 2 clinical datasets to correlate GQI, histology, and survival. Results: In a rodent glioblastoma model, GQI demonstrated a poorly coherent core region, consisting of diffusion tracts <5 mm, surrounded by a shell of highly coherent diffusion tracts, 6-25 mm. Histologically, the core region possessed a high degree of necrosis, whereas the shell consisted of organized sheets of anaplastic cells with elevated mitotic index. These attributes define tumor architecture as the macroscopic organization of variably aligned tumor cells. Applied to MRI data from The Cancer Imaging Atlas (TCGA), the core-shell diffusion tract-length ratio (c/s ratio) correlated linearly with necrosis, which, in turn, was inversely associated with survival (p = 0.00002). We confirmed in an independent cohort of patients (n = 62) that the c/s ratio correlated inversely with survival (p = 0.0004). Conclusions: The analysis of MR images by GQI affords insight into tumor architectural patterns in glioblastoma that correlate with biological heterogeneity and clinical outcome.