About
78
Publications
8,638
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,065
Citations
Introduction
Agnieszka Banas currently works at the Singapore Synchrotron Light Source, National University of Singapore. Agnieszka does research in Materials Science, Solid State Physics and Experimental Physics.
Additional affiliations
January 2007 - January 2017
Publications
Publications (78)
Forensic science is a field that requires precise and reliable methods for the detection and analysis of evidence. One such method is Fourier Transform Infrared (FTIR) spectroscopy, which provides high sensitivity and selectivity in the detection of samples. In this study, the use of FTIR spectroscopy and statistical multivariate analysis to identi...
ATR–FTIR (attenuated total reflection–Fourier-transform infrared) microscopy with imaging is widely used in the heritage field to characterise complex compositions of paint cross-sections. However, some limitations include the need for ATR crystal contact with the sample and the inability to resolve particle size below the IR diffraction limit. Rec...
There is a considerable interest in developing new analytical tools to fight the illicit trafficking of heritage goods and particularly of easel paintings, whose high market values attract an ever-increasing volume of criminal activities. The objective is to combat the illicit traffic of smuggled or forged paintworks and to prevent the acquisition...
In this work we discuss how different accelerator-based techniques can be employed synergistically in order to provide a powerful analytical tool for forensic studies of foodstuff. To that end, a Brazilian coffee was chosen as a showcase due to its popularity and potential risk of adulteration and/or falsification. A comprehensive characterization...
Malaria, caused by parasites of the species Plasmodium, is among the major life-threatening diseases to afflict humanity. The infectious cycle of Plasmodium is very complex involving distinct life stages and transitions characterized by cellular and molecular alterations. Therefore, novel single-cell technologies are warranted to extract details pe...
Antiferromagnetic insulators are a ubiquitous class of magnetic materials, holding the promise of low-dissipation spin-based computing devices that can display ultra-fast switching and are robust against stray fields. However, their imperviousness to magnetic fields also makes them difficult to control in a reversible and scalable manner. Here we d...
Malaria is one of the major life-threatening diseases to afflict humanity with an estimated 228 million cases worldwide in 2018. There exists no approved Malaria vaccine on the market yet, partly due to the complexity of the parasite life cycle and the vast repertoire of polymorphic proteins they express during different stages of development.
In t...
As we live today under a constant threat of global terrorism, effective detection of highly energetic materials is one of the critical procedures needed at a variety of locations including airports, border checkpoints, and entrances to high security buildings. In this work, the application of O-PTIR (Optical- Photothermal InfraRed) spectromicroscop...
The objective of this work was to measure infrared spectra of high explosive materials (HE) in wide spectral range in order to acquire information for their complete characterization and find out the regions that are the most discriminatory for each material. Four HEs were measured by means of Fourier Transform Infrared Spectroscopy (FTIR) in a ver...
High performance carbon nanotube fibres and yarns with similar strength to Kevlar could now offer significant structural reinforcement and multifunctionality to 3D printed parts. However, recently printed parts which were reinforced with highly-densified CNT yarns exhibited only modest mechanical properties due to poor wettability with polymers. In...
Separating enantiomers is vital in chemical syntheses, life sciences, and physics. However, the usual chemical processes are inefficient. Recently, plasmonic nanostructures have drawn considerable attention for manipulating nanoparticles; however, only a few approaches are proposed to discriminate between entities that differ in terms of their hand...
Lightweight nanocomposites reinforced with carbon nanotube (CNT) assemblies raise the prospects for a range of high-tech engineering applications. However, a correlation between their heterogeneous chemical structure and spatial organization of nanotubes should be clearly understood to maximize their performance. Here, we implement the advanced ima...
Objective:
The goal of this contribution is to present and familiarize the medical community with the method for the assessment of trace and essentials elements in prostate tissue sections.
Materials and methods:
X-ray fluorescence based technique(namely Synchrotron Induced X-ray Emission (SRIXE)) is described in terms of methodology, sample pre...
The intense light–matter interaction of plasmonic metasurfaces provides an appealing platform for optical sensing. To date, most metasurface sensors are not spectrally tuned. Moreover, they operate in a total reflection mode, which complicates the optical setup. Transmissive tunable filters are therefore desirable. A mid‐infrared (M‐IR) tunable met...
Modern technique combining infra-red spectroscopy and atomic force microscopy (AFM-IR) allows the chemical mapping with the spatial resolution down to 30 nm. However, due to specific detection of the infrared signal special attention must be paid to data-processing stage. The obtained results were carefully evaluated with the help of open source so...
In the contemporary spectroscopy there is a trend to record spectra with the highest possible spectral resolution. This is clearly justified if the spectral features in the spectrum are very narrow (for example infra-red spectra of gas samples). However there is a plethora of samples (in the liquid and especially in the solid form) where there is a...
In this work, we present the first-of-this-kind analysis of the chemical structure of CNT fibre-reinforced nanocomposites by means of AFM-IR spectroscopy. The morphology and polymer distribution within the infiltrated CNT fibre could be unravelled with sub-40 nm spatial resolution, including nanoscale chemical imaging of the polymer interphase form...
Lactose and saccharose have the same molecular formula; however, the arrangement of their atoms is different. A major difference between lactose and saccharose with regard to digestion and processing is that it is not uncommon for individuals to be lactose intolerant (around two thirds of the population has a limited ability to digest lactose after...
We report on the investigation of Si and Pd/Rh chemical environments using X-ray Absorption Near Edge Spectroscopy in two different families of rare earth silicides R2PdSi3 (R=Ce, Nd, Tb, Dy, Ho, Er) and HoRh2-x Pd x Si2 (x =0, 0.5, 0.75, 1.0, 1.5, 1.8, 2.0). The Si K, Pd L3 and Rh L3 absorption edges were recorded in order to follow their changes...
Objectives:
The aim of this study was to determine the Weibull and slow crack growth (SCG) parameters of bulk-fill resin based composites. The strength degradation over time of the materials was also assessed by strength-probability-time (SPT) analysis.
Methods:
Three bulk-fill [Tetric EvoCeram Bulk Fill (TBF); X-tra fil (XTR); Filtek Bulk-fill...
Branchlike nano-electrode structures were found to improve the THz emission intensity of a photomixer by approximately one order of magnitude higher than that of a photomixer with one row of nano-electrodes separated by the same 100 nm gap. The enhancement is attributed to a more efficient collection of generated carriers, which is in turn due to a...
Pre-processing of Fourier transform infrared (FTIR) spectra is typically the first and crucial step in data analysis. Very often hyperspectral datasets include the regions characterized by the spectra of very low intensity, for example two-dimensional (2D) maps where the areas with only support materials (like mylar foil) are present. In that case...
The pituitary gland is a small but vital organ in the human body. It is located at the base of the brain and is
often described as the master gland due to its multiple functions. The pituitary gland secretes and stores
hormones, such as the thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), growth
hormone (hGH), prolactin, gonad...
Silicon and porous silicon based photonic crystals are key aspects of photonic circuits with good compatibility with integrated circuits. Here a brief review is carried out on the fabrication of mid infrared photonic crystals using experimental processes of combining ion beam irradiation and electrochemical anodisation of silicon. Experimental proc...
We present and demonstrate a new type of single resonator based planar metamaterial exhibiting electromagnetically induced transparency (EIT)-like transmission behavior. The novel design involves physically coupled split-ring resonator (SRR) and a dipolar ring as opposed to many inductively coupled resonators explored in the past. Both experiments...
Understanding the spatial heterogeneity within environmental biofilms can provide an insight into compartmentalization of different functions in biofilm communities. We used a non-destructive and label-free method by combining Synchrotron Radiation-based Fourier Transform Infrared Microspectroscopy (SR-FTIR) with Confocal Laser Scanning Microscopy...
Assessment of the performance and up-to-date diagnostic of scientific equipment is one of the key components in contemporary laboratories. Most reliable checks are performed by real test experiments while varying the experimental conditions (typically, in case of infra-red spectroscopic measurements, size of the beam - aperture, duration of the exp...
Fingerprint evidence offers great value to criminal investigations since it is an internationally recognized and established means of human identification. With recent advances in modern technology, scientists have started analyzing not only the ridge patterns of fingerprints but also substances which can be found within them. The aim of this work...
X-ray Absorption Fine Structure (XAFS) spectroscopy was used to identify directly the metal speciation and local bonding environment of Fe in sediments originated from Dobczyce reservoir (Poland); special attention was paid to analysis of samples collected from points situated at different distances from the land. The combination of traditional app...
In this paper, we present the first experimental demonstration of double- and triple-band negative refraction index meta-foils in the terahertz (THz) region. Multi-band meta-foils constructed by multi-cell S-string resonators in a single structure exhibit simultaneously negative permittivity and negative permeability responses at multiple frequenci...
Life sciences have seen a huge increase in the amount and complexity of
data being collected with every experiment. Scientists today are faced
with increasingly difficult task to extract vital information from the
vast amount of numbers. Software used for this purpose should be
sufficiently powerful and flexible to handle large and complex data
set...
THz meta-foils have been introduced as an electromagnetic metamaterial, and their properties depend only on the geometric structure and the metal. Upon showing that conventional parallel-string meta-foils exhibit a strong polarization dependence, we propose and manufacture crossed meta-foils and demonstrate experimentally and numerically that their...
A 3D silicon micromachining method based on proton beam writing combined with electrochemical anodization of p-type silicon enables fabrication of mid-infrared photonic crystals made of silicon and porous silicon. Here, example structures of silicon 1D and 2D photonic crystals are demonstrated. Progress and problems of fabricating 3D photonic cryst...
The availability of novel technologies that enable the fabrication of bulk metamaterials made it necessary to develop a theoretical language to discuss their properties appropriately. Here we use the fundamental Bloch mode approximation to explore bulk properties of metamaterials that operate at terahertz frequencies. We demonstrate that this appro...
Multicrystalline silicon wafer solar cells reveal performance- reducing defects by luminescence. X-ray fluorescence spectra are used to investigate the elemental constituents from regions of solar cells yielding reverse-bias or sub-bandgap luminescence from defects. It is found that a higher concentration of metals is present in regions yielding re...
Synchrotron radiation sources have proven to be highly beneficial in many fields of research for the characterization of materials. Recently also forensic science community have started to appreciate the extraordinary brilliance, very broad spectral range and other features of synchrotron radiation. This is an area in which the analytical benefits...
A method for fabrication of three-dimensional (3D) silicon nanostructures based on selective formation of porous silicon using ion beam irradiation of bulk p-type silicon followed by electrochemical etching is shown. It opens a route towards the fabrication of two-dimensional (2D) and 3D silicon-based photonic crystals with high flexibility and ind...
Synchrotron radiation-based Fourier transform infra-red (SR-FTIR) micro-imaging has been developed as a rapid, direct and non-destructive technique. This method, taking advantage of the high brightness and small effective source size of synchrotron light, is capable of exploring the molecular chemistry within the microstructures of microscopic part...
Zinc is a vital element in the nutrition of human beings, animals and plants. Although most experimental data have demonstrated the adverse effects of Zn deficiency on human and animal health, there is still evidence to support the hypothesis that Zn toxicity can also result in deleterious health effects. Conflicting views have been expressed regar...
Mechanical milling induced atomic disorder and the mechanism of the cyclic crystal → amorphous → crystal phase transitions in a Nd2Fe14B intermetallic – based Nd10Fe85B5 alloy were investigated. Least square first shell fitting of Extended X-ray Absorption Fine-Structure (EXAFS) data of mechanically milled samples revealed that phase evolution duri...
The prostate gland is the most common site of neoplastic disorders in men. The pathogenesis of inflammatory cells, prostatic intraepithelial neoplasia (PIN) lesions, and prostate cancer is still under investigation. Inflammatory cells by producing free radicals are considered as major and universal contributors to cancerogenesis. PIN is regarded as...
The Extended X-ray Absorption Fine-Structure (EXAFS) technique was used to study the time evolution of the structure of Nd–Fe–B metallic glass undergoing nanocrystallization during mechanical milling. Negative as well as positive fluctuations in atomic density were observed, providing direct evidence of the creation of deformation-induced pairs of...
The meta-foil is an all-metal self-supported electromagnetic metamaterial that features a space-grid that is locally stiff, yet globally flexible. Owing to its mechanical, thermal, chemical and radiative robustness, it lends itself to widespread applications.
Fourier transform infrared (FTIR) spectroscopy has gained significant attention among the forensic scientists because it shows high sensitivity and selectivity, and offers near-real-time detection. Application of the multivariate statistical techniques for the analysis of the spectra is necessary in order to enable feature extraction, proper evalua...
The structural, surfacial and nanoscale mechanical properties evolution of Ti–Ni–Cu thin films, prepared by the co-sputtering of TiNi and Cu targets during rapid thermal annealing (RTA) were investigated. Crystallization took place in a few seconds at 480 °C. With increasing annealing time (up to 180 s), roughness increased dramatically, and was fa...
International terrorism is one of the most serious security threats that societies face today. This highlights the need for fast and accurate investigation techniques for evaluating vital clues left behind by the terrorists' bomb blasts. Synchrotron-based Fourier Transform InfraRed (FTIR) spectroscopy is the method of choice in many applications be...
The meta-foil, an all-metal fully self-supported locally stiff and globally flexible metamaterial, is presented. Its architecture is based on an array of parallel S-strings interconnected by transverse metal rods that are periodically repeated along the strings. For the present samples, this period is about once or twice the length of an S, which i...
The function of metamaterials relies on their resonant response to electromagnetic waves in characteristic spectral bands. To make metamaterials homogeneous, the size of the basic resonant element should be less than 10% of the wavelength. For the THz range up to the visible, structure details of 50 nm to 30 μm are required as are high aspect ratio...
The sorption ability of fast-coprecipitated and hydrothermally-treated Mg/Al layered double hydroxide nanoparticles (FCHT-LDH) for various oxyhalides and oxyanions was evaluated. Interactions of oxyhalide such as monovalent bromate or oxyanions such as divalent chromate and divalent vanadate with FCHT-LDH were investigated using a combination of ma...
The causes of prostate cancer are still obscure but some evidence indicates that there is a close connection between several trace elements and processes which may lead to malignant cells. In our study the microbeam synchrotron radiation X-ray fluorescence emission (micro-SRIXE) technique was applied for quantitative analysis of selected elements....
Meta-foils are all-metal free-standing electromagnetic metamaterials based on interconnected S-string architecture. They provide a versatile applications' platform. Lacking any substrate or embedding matrix, they feature arrays of parallel upright S-strings with each string longitudinally shifted by half an S compared to its neighbour to form capac...
Fourier transform-infrared (FT-IR) spectroscopy has gained considerable attention among the forensic scientists because it shows high sensitivity and selectivity and offers near real time detection of analyzed samples. However, the amount of obtained information due to complexity of the measured spectra forces the use of additional data processing....
The infrared spectromicroscopy is a quite recent technique rapidly developing thanks to the availability of new instruments and new brilliant synchrotron radiation sources in different areas and in particular to biomedical researches. In order to achieve a diffraction limited spatial resolution in tissue samples, we performed experiments at SINBAD,...
Samples obtained from debris after explosions of about 30 g of energetic materials were analyzed by means of Fourier transform infrared (FTIR) spectroscopy using both, Globar and synchrotron infrared radiation at the ISMI beamline of the Singapore synchrotron light source (SSLS). Low- and high-strength-of-explosion blasts were performed during each...
Elemental maps obtained by micro-synchrotron radiation induced X-ray emission technique can be manipulated in several ways to extract useful information. In this paper the method of displaying the correlation between two or three elements in one correlation map is described. Such types of maps give precise information about the overlap between the...
Apolipoprotein E and LDL receptor double-knockout (apoE/LDLR−/−) mice represent a reliable experimental model of atherosclerosis. The aim of the present study was to examine the elemental content of atherosclerotic plaques using synchrotron radiation-induced micro x-ray fluorescence (XRF) spectrometry. Numerous essential and trace elements were det...
The results of XANES and Mössbauer spectroscopy studies of organic samples of [Fe(Hka)3] (Hka = kojic acid) and [Fe(etmal)3] (etmal = ethyl maltol) are presented and discussed in terms of their application in characterization of the local electronic state of Fe3+. In case of [Fe(etmal)3], a tiny increase in covalency of iron bonds was found. The lo...
The ability to visualize an object of interest is one of the cornerstones of advancement in science. For this reason, synchrotron radiation-induced X-ray emission (micro-SRIXE) holds special promise as a imaging technique in structural biology, biochemistry, and medicine. It gives the possibility to image concentration of most of the elements in a...
BPH (Benign Prostatic Hyperplasia) is the most common benign neoplasm (non cancerous enlargement of the prostate gland), whose prevalence increases with age.The gland, when increased in size, exerts pressure on the urethra, causing obstruction to urine flow. The latter may result in severe urinary tract and kidney conditions.In this work prostate s...
Synchrotron radiation Fourier transform infrared (SR-FTIR) spectroscopy belongs to modern spectroscopic techniques and has been very often used to study chemical composition of different types of tissue. A microscope setup attached to the SR-FTIR spectrometer enables tissue analysis to be done at micrometer scale. Prostate diseases including hyperp...
Sulphur is vital for almost all living organisms by participating in a wide variety of metabolic processes. Nevertheless its biochemistry is only partially understood, due to it a few tools such as X-ray absorption near edge structure may be used to determine its chemical speciation in biological system. In this paper we focused on analysis of comp...
Contribution to a conf. proceeding (journal)
The prostate gland is the most common site of neoplastic disorders in men. The knowledge of the pathogenesis of benign prostate hyperplasia and prostate cancer is still under investigation. X-ray fluorescence analysis using synchrotron radiation seems to be an appropriate technique to study the elemental composition of biological tissues. The measu...
Synchrotron radiation-induced X-ray emission is now a proven analytical method for the determination of trace elements. Better insight of the role of trace elements in tissue samples can be gained by acquiring complete distribution maps of these elements. Our approach is based on the acquisition of digital maps. In this contribution we present two...
Synchrotron radiation induced X-ray emission (SRIXE) analysis of trace element (TE) concentrations in prostate tissues shows the significant differences between elemental concentrations in cancer and healthy parts of tissues. The analysis enables obtaining additional information about the prostate cancer, almost the most dangerous disease of the re...
To understand the role of trace elements in the oxidative stress, which may be an important factor in the pathogenesis of prostate cancer, we investigated the distribution and chemical state of Fe using synchrotron radiation. Therefore, both synchrotron radiation induced X-ray emission (SRIXE) and X-ray absorption near-edge structure (XANES) techni...