Anjani K. Maurya studied bachelor of technology (B.Tech) in engineering physics at the Indian Institute of Technology Guwahati, India, and masters in materials science exploring large-scale facilities at the University of Rennes 1, France, and the Technical University of Munich, Germany, in the framework of Erasmus Mundus program. He worked at the center for X-ray analytics and the laboratory for biomimetic membranes and textiles at Swiss Federal Laboratories for Materials Science and Technology (Empa) and obtained his Ph.D. in Biomedical Engineering from the University of Bern, Switzerland.
Honors & Awards
Best poster presentation award, EXCITE Biomedical Imaging Summer School, ETH Zurich, Switzerland (Sept-2018)
IUCr Young Scientist Award, EPDIC-2020 (May-2020)
Young Scientist Award to attend the conference, SAS2022 (July-2022)
Erasmus+ Scholarship, European Union (2015-2016)
World Quantitative and Science Scholarship, World Quant Foundation (2014-2015)
IIT Guwahati Institute Merit-cum-Means (McM) Scholarship, Government of India (2012-2014)
Piero Pianetta, Postdoctoral Faculty Sponsor
Curriculum and Instruction
Superinsulating nanocellulose aerogels: Effect of density and nanofiber alignment.
2022; 292: 119675
Cellulose aerogels are potential alternatives to silica aerogels with advantages in cost, sustainability and mechanical properties. However, the density dependence of thermal conductivity (lambda) for cellulose aerogels remains controversial. Cellulose aerogels were produced by gas-phase pH induced gelation of TEMPO-oxidized cellulose nanofibers (CNF) and supercritical drying. Their properties are evaluated by varying the CNF concentration (5-33mg·cm-3) and by uniaxial compression (9-115mg·cm-3). The aerogels are transparent with specific surface areas of ~400m2·g-1, mesopore volumes of ~2cm3·g-1 and a power-law dependence of the E-modulus (alpha~1.53, and the highest reported E of ~1MPa). The dataset confirms that lambda displays a traditional U-shaped density dependence with a minimum of 18mW·m-1·K-1 at 0.065g·cm-3. For a given density, lambda is ~5mW·m-1·K-1 lower for compressed aerogels due to the alignment of nanofibers, confirmed by small angle X-ray scattering (SAXS).
View details for DOI 10.1016/j.carbpol.2022.119675
View details for PubMedID 35725170
Redesigned Hybrid Nylons with Optical Clarity and Chemical Recyclability.
Journal of the American Chemical Society
Aliphatic polyamides, or nylons, are typically highly crystalline and thermally robust polymers used in high-performance applications. Nylon 6, a high-ceiling-temperature (HCT) polyamide from epsilon-caprolactam, lacks expedient chemical recyclability, while low-ceiling temperature (LCT) nylon 4 from pyrrolidone exhibits complete chemical recyclability, but it is thermally unstable and not melt-processable. Here, we introduce a hybrid nylon, nylon 4/6, based on a bicyclic lactam composed of both HCT epsilon-caprolactam and LCT pyrrolidone motifs in a hybridized offspring structure. Hybrid nylon 4/6 overcomes trade-offs in (de)polymerizability and performance properties of the parent nylons, exhibiting both excellent polymerization and facile depolymerization characteristics. This stereoregular polyamide forms nanocrystalline domains, allowing optical clarity and high thermal stability, however, without displaying a melting transition before decomposition. Of a series of statistical copolymers comprising nylon 4/6 and nylon 4, a 50/50 copolymer achieves the greatest synergy in both reactivity and polymer properties of each homopolymer, offering an amorphous nylon with favorable properties, including optical clarity, a high glass transition temperature, melt processability, and full chemical recyclability.
View details for DOI 10.1021/jacs.1c12611
View details for PubMedID 35290039
- Tailoring Fibre Structure Enabled by X-ray Analytics for Targeted Biomedical Applications CHIMIA 2022; 76 (3): 229-235
- In-situ Investigations on Gold Nanoparticles Stabilization Mechanisms in Biological Environments Containing HSA ADVANCED FUNCTIONAL MATERIALS 2021
- Understanding multiscale structure-property correlations in PVDF-HFP electrospun fiber membranes by SAXS and WAXS NANOSCALE ADVANCES 2021
Unraveling the Influence of Thermal Drawing Parameters on the Microstructure and Thermo-Mechanical Properties of Multimaterial Fibers.
Small (Weinheim an der Bergstrasse, Germany)
Multimaterial thermally drawn fibers are becoming important building blocks in several foreseen applications in surgical probes, protective gears, or medical textiles. Here, the influence of the thermal drawing parameters on the degree of polymer chain orientation, the related thermal shrinkage behavior, and the mechanical properties of the final fibers is investigated via thermo-mechanical testing and small- and wide-angle X-ray scattering (SAXS and WAXS) analyses. This study on polyetherimide fibers reveals that the drawing stress, which depends on the drawing speed and temperature, controls the thermal shrinkage behavior and mechanical properties. Furthermore, SAXS and WAXS analyses show that the degree of chain orientation increases with drawing stresses below 8MPa and then saturates, which correlates with the amount of observed shrinkage. The use of this process-dependent polymer chain alignment to tune the mechanical and shrinkage properties of the fibers is highlighted and controlled bending multimaterial fibers made of two polymethyl methacrylates having different molecular weights are developed. Finally, a heat treatment procedure is proposed to relax the chain alignment and increase the dimensional stability of devices such as temperature sensors. This deeper understanding can serve as a guide for the processing of complex fibers requiring specific mechanical properties or enhanced thermal stability.
View details for DOI 10.1002/smll.202101392
View details for PubMedID 34761869
Multiscale and multimodal X-ray analysis: Quantifying phase orientation and morphology of mineralized turkey leg tendons
2021; 129: 169-177
Fibrous biocomposites like bone and tendons exhibit a hierarchical arrangement of their components ranging from the macroscale down to the molecular level. The multiscale complex morphology, together with the correlated orientation of their constituents, contributes significantly to the outstanding mechanical properties of these biomaterials. In this study, a systematic road map is provided to quantify the hierarchical structure of a mineralized turkey leg tendon (MTLT) in a holistic multiscale evaluation by combining micro-Computed Tomography (micro-CT), small-angle X-ray scattering (SAXS), and wide-angle X-ray diffraction (WAXD). We quantify the interplay of the main MTLT components with respect to highly ordered organic parts such as fibrous collagen integrating inorganic components like hydroxyapatite (HA). The microscale fibrous morphology revealing different types of porous features and their orientation was quantified based on micro-CT investigations. The quantitative analysis of the alignment of collagen fibrils and HA crystallites was established from the streak-like signal in SAXS using the Ruland approach and the broadening of azimuthal profiles of the small and wide-angle diffraction peaks. It has been in general agreement that HA crystallites are co-aligned with the nanostructure of mineralized tissue. However, we observe relatively lower degree of orientation of HA crystallites compared to the collagen fibrils, which supports the recent findings of the structural interrelations within mineralized tissues. The generic multiscale characterization approach of this study is relevant to any hierarchically structured biomaterials or bioinspired materials from the μm-nm-Å scale. Hence, it gives the basis for future structure-property relationship investigations and simulations for a wide range of hierarchically structured materials. STATEMENT OF SIGNIFICANCE: Many fibrous biocomposites such as tendon, bone, and wood possess multiscale hierarchical structures, responsible for their exceptional mechanical properties. In this study, the 3-dimensional hierarchical structure, the degree of orientation and composition of mineralized tendon extracted from a turkey leg were quantified using a multimodal X-ray based approach combining small-angle X-ray scattering and wide-angle X-ray diffraction with micro-Computed Tomography. We demonstrate that hydroxyapatite (HA) domains are co-aligned with the nanostructure of mineralized tissue. However, the lower degree of orientation of HA crystallites was observed when compared to the collagen fibrils. The generic multiscale characterization approach of this study is relevant to any hierarchically structured biomaterials or bioinspired materials from the micrometer over the nanometer to the Angström scale level.
View details for DOI 10.1016/j.actbio.2021.05.022
View details for Web of Science ID 000671497100002
View details for PubMedID 34052502
- Effect of radiant heat exposure on structure and mechanical properties of thermal protective fabrics POLYMER 2021; 222
- Template-free synthesis of hybrid silica nanoparticle with functionalized mesostructure for efficient methylene blue removal MATERIALS & DESIGN 2021; 201
- Polyhydroxyoctanoate films reinforced with titanium dioxide microfibers for biomedical application MATERIALS LETTERS 2021; 285
Combining polarized Raman spectroscopy and micropillar compression to study microscale structure-property relationships in mineralized tissues
2021; 119: 390-404
Bone is a natural composite possessing outstanding mechanical properties combined with a lightweight design. The key feature contributing to this unusual combination of properties is the bone hierarchical organization ranging from the nano- to the macro-scale. Bone anisotropic mechanical properties from two orthogonal planes (along and perpendicular to the main bone axis) have already been widely studied. In this work, we demonstrate the dependence of the microscale compressive mechanical properties on the angle between loading direction and the mineralized collagen fibril orientation in the range between 0° and 82°. For this, we calibrated polarized Raman spectroscopy for quantitative collagen fibril orientation determination and validated the method using widely used techniques (small angle X-ray scattering, micro-computed tomography). We then performed compression tests on bovine cortical bone micropillars with known mineralized collagen fibril angles. A strong dependence of the compressive micromechanical properties of bone on the fibril orientation was found with a high degree of anisotropy for both the elastic modulus (Ea/Et=3.80) and the yield stress (σay/σty=2.54). Moreover, the post-yield behavior was found to depend on the MCF orientation with a transition between softening to hardening behavior at approximately 50°. The combination of methods described in this work allows to reliably determine structure-property relationships of bone at the microscale, which may be used as a measure of bone quality.
View details for DOI 10.1016/j.actbio.2020.10.034
View details for Web of Science ID 000603041300006
View details for PubMedID 33122147
Responsive Nanofibers with Embedded Hierarchical Lipid Self-Assemblies
2020; 36 (40): 11787-11797
We introduce the design and study of a hybrid electrospun membrane with a dedicated nanoscale structural hierarchy for controlled functions in the biomedical domain. The hybrid system comprises submicrometer-sized internally self-assembled lipid nanoparticles (ISAsomes or mesosomes) embedded into the electrospun membrane with a nanofibrous polymer network. The internal structure of ISAsomes, studied by small-angle X-ray scattering (SAXS) and electron microscopy, demonstrated a spontaneous response to variations in the environmental conditions as they undergo a bicontinuous inverse cubic phase (cubosomes) in solution to a crystalline lamellar phase in the polymer membrane; nevertheless, this phase reorganization is reversible. As revealed by in situ SAXS measurements, if the membrane was put in contact with aqueous media, the cubic phase reappeared and submicrometer-sized cubosomes were released upon dissolution of the nanofibers. Furthermore, the hybrid membranes exhibited a specific anisotropic feature and morphological response under an external strain. While nanofibers were aligned under external strain in the microscale, the semicrystalline domains from the polymer phase were positioned perpendicular to the lamellae of the lipid phase in the nanoscale. The fabricated membranes and their spontaneous responses offer new strategies for the development of structure-controlled functions in electrospun nanofibers for biomedical applications, such as drug delivery or controlled interactions with biointerfaces.
View details for DOI 10.1021/acs.langmuir.0c01487
View details for Web of Science ID 000580967600008
View details for PubMedID 32936649
Polarimetric imaging in backscattering for the structural characterization of strongly scattering birefringent fibrous media
2020; 28 (11): 16673-16695
Interpreting the polarimetric data from fiber-like macromolecules constitutive of tissue can be difficult due to strong scattering. In this study, we probed the superficial layers of fibrous tissue models (membranes consisting of nanofibers) displaying varying degrees of alignment. To better understand the manifestation of membranes' degree of alignment in polarimetry, we analyzed the spatial variations of the backscattered light's Stokes vectors as a function of the orientation of the probing beam's linear polarization. The degree of linear polarization reflects the uniaxially birefringent behavior of the membranes. The rotational (a-)symmetry of the backscattered light's degree of linear polarization provides a measure of the membranes' degree of alignment.
View details for DOI 10.1364/OE.390303
View details for Web of Science ID 000542303000074
View details for PubMedID 32549485
Structural insights into semicrystalline states of electrospun nanofibers: a multiscale analytical approach
2019; 11 (15): 7176-7187
A dedicated nanofiber design for applications in the biomedical domain is based on the understanding of nanofiber structures. The structure of electrospun nanofibers strongly influences their properties and functionalities. In polymeric nanofibers X-ray scattering and diffraction methods, i.e. SAXS and WAXD, are capable of decoding their structural insights from about 100 nm down to the Angström scale. Here, we present a comprehensive X-ray scattering and diffraction based study and introduce new data analysis approaches to unveil detailed structural features in electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (PVDFhfp) nanofiber membranes. Particular emphasis was placed on anisotropic morphologies being developed during the nanofiber fabrication process. Global analysis was performed on SAXS data to derive the nanofibrillar structure of repeating lamella crystalline domains with average dimensions of 12.5 nm thickness and 7.8 nm spacing along with associated tie-molecules. The varying surface roughness of the nanofiber was evaluated by extracting the Porod exponent in parallel and perpendicular direction to the nanofiber axis, which was further validated by Atomic Force Microscopy. Additionally, the presence of a mixture of the monoclinic alpha and the orthorhombic beta PVDFhfp phases both exhibiting about 6% larger unit cells compared to the corresponding pure PVDF phases was derived from WAXD. The current study shows a generic approach in detailed understanding of internal structures and surface morphology for nanofibers. This forms the basis for targeted structure and morphology steering and the respective controlling during the fabrication process with the aim to engineer nanofibers for different biomedical applications with specific requirements.
View details for DOI 10.1039/c9nr00446g
View details for Web of Science ID 000465315900011
View details for PubMedID 30919869
- Facile Optimization of Thermoelectric Properties in PEDOT:PSS Thin Films through Acido-Base and Redox Dedoping Using Readily Available Salts ACS APPLIED ENERGY MATERIALS 2018; 1 (2): 336-342