bluuebunny/crossref_metadata_2025 huggingface dataset:
Driving Forces of Water Intensity in China’s Industrial Sector: A Global Meta-Frontier Production–Theoretical Decomposition Analysis
Authors: Ding Tao , Li Jiangyuan , Shi Xing , Wu Huaqing
Published: July 2021

The shortage of water resources has prohibited the sustainable growth of China. Identifying the driving forces of water intensity is critical to initiating cost-effective policies and regulations to reduce water consumption across China. We develop a global meta-frontier production decomposition approach, which could simultaneously address the spatial and temporal heterogeneities, to decompose the water intensity of the industrial sector in China at various levels from 2011 to 2015. Results show that the industrial water intensity in all provinces except Shanxi has been declining over the sample period, with little potential for a further reduction. Second, at the national level, the potential water usage factor and the temporal catch-up effect of water usage technology are two significant contributors in reducing the industrial water intensity. Third, we find that some factors have mixed results at the regional and provincial levels, calling for customized policies in these aspects. Our approach provides a more precise decomposition and reveals more details in China’s variations of industrial water intensity, which has manifold implications for regional water management.
The Study of Three-Dimensional Fingerprint Recognition in Cultural Heritage
Authors: Sero Dzemila , Garachon Isabelle , Hermens Erma , Liere Robert Van , Batenburg Kees Joost
Published: July 2021

Fingerprints play a central role in any field where person identification is required. In forensics and biometrics, three-dimensional fingerprint-based imaging technologies, and corresponding recognition methods, have been vastly investigated. In cultural heritage, preliminary studies provide evidence that the three-dimensional impressions left on objects from the past (ancient fingerprints) are of paramount relevance to understand the socio-cultural systems of former societies, to possibly identify a single producer of multiple potteries, and to authenticate the artist of a sculpture. These findings suggest that the study of ancient fingerprints can be further investigated and open new avenues of research. However, the potential for capturing and analyzing ancient fingerprints is still largely unexplored in the context of cultural heritage research. In fact, most of the existing studies have focused on plane fingerprint representations and commercial software for image processing. Our aim is to outline the opportunities and challenges of digital fingerprint recognition in answering a range of questions in cultural heritage research. Therefore, we summarize the fingerprint-based imaging technologies, reconstruction methods, and analyses used in biometrics that could be beneficial to the study of ancient fingerprints in cultural heritage. In addition, we analyze the works conducted on ancient fingerprints from potteries and ceramic/fired clay sculptures. We conclude with a discussion on the open challenges and future works that could initiate novel strategies for ancient fingerprint acquisition, digitization, and processing within the cultural heritage community.
FAST CAT
Authors: Fafalios Pavlos , Petrakis Kostas , Samaritakis Georgios , Doerr Korina , Kritsotaki Athina , Tzitzikas Yannis , Doerr Martin
Published: July 2021

Descriptive and empirical sciences, such as History, are the sciences that collect, observe and describe phenomena to explain them and draw interpretative conclusions about influences, driving forces and impacts under given circumstances. Spreadsheet software and relational database management systems are still the dominant tools for quantitative analysis and overall data management in these these sciences, allowing researchers to directly analyse the gathered data and perform scholarly interpretation. However, this current practice has a set of limitations, including the high dependency of the collected data on the initial research hypothesis, usually useless for other research, the lack of representation of the details from which the registered relations are inferred, and the difficulty to revisit the original data sources for verification, corrections or improvements. To cope with these problems, in this article we present FAST CAT, a collaborative system for assistive data entry and curation in Digital Humanities and similar forms of empirical research. We describe the related challenges, the overall methodology we follow for supporting semantic interoperability, and discuss the use of FAST CAT in the context of a European (ERC) project of Maritime History, called
SeaLiT
, which examines economic, social and demographic impacts of the introduction of steamboats in the Mediterranean area between the 1850s and the 1920s.
The web conference keynote - AI grand challenges
Authors: Mani Ganesh
Published: July 2021

Everybody has opinions on grand challenges---bold tasks that capture the imagination of researchers and system builders---for AI. One of the earliest set of challenge goals was enunciated by Turing award winner and AAAI President, Raj Reddy, in 1988. I attempt to provide an accounting of the progress that has been made in the field, over the last three decades, towards those challenge goals. While some tasks such as the world-champion chess machine were accomplished in short order, many others remain incomplete. A new set of challenges for the current decade are also proposed, spanning the Health, Wealth and Wisdom spheres. Bridging the gap from narrow AI to general-purpose AI will be required to solve some of these challenges; teaming architectures in the service of humankind will also need to be emphasized. The mantra should be: Of the people, by the peoplewith machines; for the people!
Report on the FIRE 2020 evaluation initiative
Authors: Mehta Parth , Mandl Thomas , Majumder Prasenjit , Gangopadhyay Surupendu
Published: July 2021

This report gives an overview on the Forum for Information Retrieval Evaluation (FIRE) initiative for South-Asian languages
1
. The FIRE conference was conducted online in December 2020. The event combined a conference including keynotes, peer reviewed paper session with an Evaluation Forum. This report will present an overview of the conference and provide insights into the evaluation tracks. Current domains include legal information access, mixed script information retrieval, semantic analysis and social media posts classification. The tasks are discussed and connections to other evaluation initiatives are shown.
(Invited) Nanodiamonds and Bioapplications
Authors: Arnault Jean-Charles
Published: July 2021

Like other nanocarbons, nanodiamond (ND) is the object of a rising interest from researchers, engineers and companies. Indeed, its outstanding properties, partly inhered from bulk diamond, are completed by new ones conferred at the nanoscale. Moreover, ND can host photostable luminescent color centers (NV, SiV, GeV,...) that can possess spin properties [1]. Combining these uncommon assets, ND are actively investigated for nanomedicine and bioapplications, quantum technologies, catalysis and energy applications, advanced composites and lubricants.

After set the scene of ND and nanomedicine, this talk will focus on the recent developments of our research group towards bioapplications using ND differing by their origin (HPHT, detonation) and their surface chemistry. These studies are based on an extended characterization of ND. Toxicity issues will be discussed with investigations of the in vitro genotoxicity of HPHT ND and a comparative ecotoxicology study involving other nanocarbons. We will illustrate that ND can act as an efficient vector for biological species of interest, either grafted at its surface thanks to the versatile carbon chemistry or loaded by electrostatic interactions. Surprisingly, we have also demonstrated that detonation ND can behave as an active nanoparticle under gamma irradiation with a radiosensitization effect [2]. More recently, tritium labelled detonation ND allowed to explore the distribution throughout mouse organs and their excretion in urine and feces [3].

References

[1] O. A. Shenderova, A. I. Shames, N. A. Nunn, M. D. Torelli, I. Vlasov, A. Zaitsev, Review Article: Synthesis, properties, and applications of fluorescent diamond particles, J. Vac. Sci. Technol. B 37 (2019) 030802. doi.org/10.1116/1.5089898

[2] R. Grall, H. A. Girard, L. Saad, T. Petit, C. Gesset, M. Combis-Schlumberger, V. Paget, J. Delic, J. C. Arnault, S. Chevillard, Impairing the radioresistance of cancer cells by hydrogenated nanodiamonds. Biomaterials 61 (2015) 290–298. doi.org/10.1016/j.biomaterials.2015.05.034

[3] S. Claveau, E. Nehlig, S. Garcia-Argote, S. Feuillastre, G. Pieters, H. A. Girard, J. C. Arnault, F. Treussart, J. R. Bertrand, Delivery of siRNA to Ewing sarcoma tumor xenografted on mice, using hydrogenated detonation nanodiamond: treatment efficacy and tissue distribution Nanomaterials 10 (2020) 553. doi:10.3390/nano10030553
(Invited) Multifunctional Carbon Nanodots for Theranostic Applications
Authors: Bianco Alberto
Published: July 2021

Carbon nanodots are a form of carbon that is attracting a lot of attention, as they are considered promising nanomaterials for future clinical translation. Carbon nanodots combine numerous characteristics including high photostability, low cytotoxicity, and superior biocompatibility. We have conceived and synthesised multifunctional carbon nanodots with deep-red emission properties through their controlled chemical modification using folic acid ligand (Figure). These carbon nanodots, endowed of a high colloidal stability and an enhanced luminescence, are suitable for targeted intracellular production of reactive oxygen species by laser irradiation leading to efficient cancer cell death [1]. In addition, we have modified carbon nanodots with a chelating agent for gadolinium. These nanodots showed a better magnetic resonance relaxivity than commercial MRI agents, resulting potential clinical tools as MRI/fluorescence dually functional imaging probes.

[1] Ji, D.-K.; Reina,G.; Guo,S.; Eredia,M.; Samorì, P.; Ménard-Moyon, C.; BiancoA. Controlled Functionalization of Red-emissive Carbon Nanodots for Targeted Intracellular Production of Reactive Oxygen Species. Nanoscale Horizons
2020, 5, 1240-1249. DOI:10.1039/D0NH00300J

Figure 1
Graphene Quantum Dots Co-Doped with Nitrogen/Mn(II) or Nitrogen/Gd(III) for Bimodal Magnetic Resonance and Fluorescence Imaging
Authors: Lee Bong Han , Hasan Md. Tanvir , Lichthardt Denise , Gonzalez-Rodriguez Roberto , Naumov Anton V.
Published: July 2021

Graphene quantum dots (GQDs) are unique derivatives of graphene that show promise in multiple biomedical applications as biosensors, bioimaging agents, and drug/gene delivery vehicles. Their ease in functionalization, biocompatibility, and intrinsic fluorescence enable those modalities. However, GQDs lack deep tissue magnetic resonance imaging (MRI) capabilities desirable for diagnostics. Considering that the drawbacks of MRI contrast agent toxicity are still poorly addressed, we develop novel Mn2+ or Gd3+ doped nitrogen-containing graphene quantum dots (NGQDs) to equip the GQDs with MRI capabilities and at the same time render contrast agents biocompatible. Water-soluble biocompatible Mn-NGQDs and Gd-NGQDs synthesized via single-step microwave-assisted scalable hydrothermal reaction enable dual MRI and fluorescence modalities. These quasi-spherical 3.9–6.6 nm average-sized structures possess highly crystalline graphitic lattice structure with 0.24 and 0.53 atomic % for Mn2+ and Gd3+ doping. This structure ensures high in vitro biocompatibility of up to 1.3 mg ml−1 and 1.5 mg ml−1 for Mn-NGQDs and Gd-NGQDs, respectively, and effective internalization in HEK-293 cells traced by intrinsic NGQD fluorescence. As MRI contrast agents with considerably low Gd and Mn content, Mn-NGQDs exhibit substantial transverse/longitudinal relaxivity (r
2/r
1) ratios of 11.190, showing potential as dual-mode longitudinal or transverse relaxation time (T
1 or T
2) contrast agents, while Gd-NGQDs possess r
2/r
1 of 1.148 with high r
1 of 9.546 mM−1 s−1 compared to commercial contrast agents, suggesting their potential as T1 contrast agents. Compared to other nanoplatforms, these novel Mn2+ and Gd3+ doped NGQDs not only provide scalable biocompatible alternatives as T1/T2 and T1 contrast agents but also enable in vitro intrinsic fluorescence imaging.
Remote Optical Modulation of Cellular Electrical Activity Using Two-Dimensional Ti3C2 MXene
Authors: Wang Yingqiao , Garg Raghav , Kang Kyoungin , Hartung Jane E. , Goad Adam , Vitale Flavia , Gold Michael S. , Gogotsi Yury , Cohen-Karni Tzahi
Published: July 2021

The ability to probe and manipulate electrophysiology at the cellular level is crucial for understanding cellular communications and enabling new therapeutics for neurological and psychiatric disorders. Nanomaterial-facilitated photothermal stimulation is a non-invasive technique to manipulate cellular electrophysiology with high spatial precision and rapid response time without the need of genetic modifications. Although recently reported Si-, Au-, and C-based nanomaterials are promising candidates for photothermal stimulation of electrically active cells and tissues, they exhibit limited photothermal conversion efficiency in the near-infrared (NIR) window or have complicated synthesis protocols that prevents direct scale-up. Two-dimensional (2D) Ti3C2 MXene is a promising candidate for optical stimulation due to its high NIR absorption and photothermal energy conversion efficiency. Here, we report an approach for optical modulation of neuronal activity using Ti3C2 MXene flakes. Under illumination with 1 ms pulses of 10 mW NIR laser (λ = 808 nm), the local temperature rise induced by single Ti3C2 MXene flakes was measured to be 3.1 ± 0.7 K. MXene films (25 µg/cm2) and dispersed MXene flakes (100 µg/mL) were evaluated to be biocompatible with dorsal root ganglia (DRG) neurons. Both MXene films and flakes enabled photothermal stimulation of DRG neurons (and DRG networks) with incident energies in the micro-joule regime. Optical stimulation of DRG neurons using Ti3C2 MXene flakes is safe and does not generate cellular stress. Due to its straightforward and large-scale synthesis, MXene can enable neuronal modulation at various scales and dimensions, thus is a powerful tool for future remote, non-genetic biological interfaces.
(Invited) Photoluminescence Study of Carbon Nanomaterial Interactions with the Immune System
Authors: Star Alexander
Published: July 2021

Carbon nanomaterials such as graphene and carbon nanotubes have attracted tremendous attention for various applications in science and technology. However, increasing use of carbon nanomaterials also necessitates careful scrutiny of their impact on human health. Understanding their interactions with different components of the innate immune system is of particular importance.

Myeloperoxidase (MPO), a key enzyme released by neutrophils during inflammation, has been shown to catalyze the biodegradation of carbon nanomaterials. We investigated the changes in photoluminescence (PL) properties of graphene oxide (GO) and single-walled carbon nanotubes (SWCNT) during MPO degradation. Increased fluorescence emission was observed with the progression of enzymatic oxidation of GO as a result of the formation of graphene quantum dots (GQDs). In contrast, the fluorescence of surfactant-coated SWCNT was either quenched or remained almost unchanged (depending on the surfactant used) during 5-day degradation. The two different PL systems were combined as SWCNT/GO nanoscrolls into ratiometric fluorescence sensors to monitor MPO activity.

Lipid metabolites play an important role in the immune response. We demonstrated a photo-induced cycloaddition reaction between oxygenated lipid metabolites containing enone functional group and SWCNTs. By creating covalent and tunable sp3 defects in the sp2 carbon lattice of SWCNTs, this photochemical reaction results in the gradual appearance of the bright red-shifted near-IR photoluminescence in SWCNTs.
(Invited) Graphene Field-Effect Transistors As Bioanalytical Sensors: Advances in Design, Fabrication and Characterization
Authors: Bouilly Delphine
Published: July 2021

Graphene field-effect transistors (GFETs) are emerging as bioanalytical sensors, in which their responsive electrical conductance is used to perform quantitative analyses of biologically-relevant molecules such as DNA, proteins, ions and small molecules. In this presentation, I will report on key principles and recent developments in the design, fabrication and performance of such GFET biomolecular sensors. In particular, I will discuss approaches for surface functionalization and patterning of graphene to optimize its coupling with molecules. I will also describe hardware and software developments for wafer-scale fabrication and multiplexed analyses of GFET sensor devices. Finally, I will discuss our work in developing such sensors for applications in fundamental biophysics and cancer diagnostics.
Carbon Nanotube Assemblies for Neuroscience Applications
Authors: Alvarez Noe , Buschbeck Elke , Miller Sydney , Gupta Vandna , Gupta Pankaj , Ruhunage Chethani
Published: July 2021

Assembling carbon nanotubes (CNTs) into macroscopic materials allows multiple applications that takes advantage of their physical properties. Specifically, the synthesis, fiber assembly, polymer coating and application of CNTs as microelectrodes has allowed us explore physiological applications as well as sensor development. This talk will summarize our research in CNT microelectrode development, neural recording and stimulation, and neurotransmitter detection and quantification through voltammetric techniques. Recordings and stimulations of neuronal electrical activity is a topic of great interest in neuroscience. Current commercial electrodes for transferring charges from solid electrode materials to and from biological tissue still have some limitations. A microelectrode that is flexible, chemically inert, electrically conducting, and preferentially transfers electrons via capacitive charge-injection is needed to treat multiple neurological disorders. This talk will compare charge transport capabilities from carbon nanotube fibers, noble metals Au and Ag wire microelectrodes to biological tissue. The recording ability of microelectrodes is demonstrated through Electroretinography (ERG) on Sarcophaga bullata fly eyes, where light stimulation generates potential changes that were detected by our microelectrodes. Stimulation is demonstrated through Au wire and carbon nanotube fiber implants in Madagascar hissing cockroach (Gromphadorhina portentosa) antennas to control their locomotion directions. In addition, CNT microelectrodes has been found to detect neurotransmitters dopamine (DA), serotonin (5-HT), epinephrine (Epn) and nor-epinephrine (Nor-epn) using voltammetric techniques with excellent limits of detection in the range of ~10-11 M. For practical applicability, the electrodes can detect in real time DA release from culture rat pheochromocytoma (PC12) cells upon concentrate K+stimulation.
What Can We Learn from Carbon Nanotube Diffusion Trajectories Recorded in the Live Brain?
Authors: Lee Antony , Danne Noemie , Paviolo Chiara , Soria Federico , Ferreira Joana , Bezard Erwan , Groc Laurent , Cognet Laurent
Published: July 2021

Luminescent single wall carbon nanotubes are now well established, as unique nanoreporters to probe the brain extracellular space[1]. On the imaging side, this comes from their rich near-infrared optical properties, which also eventually be improved by sp3-chemical functionalization[2]. In addition, their uncommon 1D morphology is an important asset for tissue penetration, yet understanding their diffusion behavior in the complex brain extracellular network is challenging and necessitates dedicated analysis tools. To this aim, we have developed two novel approaches (i) based on the local analysis of trajectory contours to locally measure the nanoscale dimensions of the brain network [3] and (ii) based on the transient evaluation of anomalous carbon nanotube diffusion to delineate the ECS molecular diffusion landscape [4]. The application of these analytical tools to extract relevant biological parameters in physiological and pathological brain models will be presented [5].

References

[1] Godin et al Nat. Nanotechnol. 12 (2017) 238-243 ; Gao, et al, Nanomaterials 7, 11, (2017) 393 ; Danné et al ACS Photonics, 5, 2, (2018) 359-364

[2] Mandal et al. Scientific Reports, 10 (2020) 5286

[3] Paviolo et al Methods 174 (2020) 91-99

[4] Lee et al, in preparation

[5] Soria et al Nat. Commun., 11 (2020) 3440
A Protein Corona-Based Design Strategy for Carbon Nanotube Sensors
Authors: Landry Markita P , Pinals Rebecca
Published: July 2021

Unpredictable protein adsorption on nanoparticles remains a considerable challenge towards effectively applying nanotechnologies in biological environments. However, if well understood and controlled, proteins adsorbed on nanoparticles can be exploited to develop protein-based nanosensors.

Herein, we employ our knowledge of spontaneous “protein corona” formation on single-walled carbon nanotubes (SWCNTs) in biofluids1 towards rational nanosensor design based on protein-SWCNT complexation.2 SWCNTs are implemented as the sensor platform due to their desirable optical and physical characteristics, including photostable fluorescence in the near-infrared tissue transparency window3 and high aspect ratio that confers delivery capabilities.4 We functionalize carbon nanotubes with proteins that, in turn, bind to their natural ligand partners. The adsorbed protein thus acts as the recognition moiety that interacts with the environment and detects the analyte of interest, tethered to the SWCNT that serves as the signal transducer. This nanosensor platform combines the sensitive and selective binding capabilities of proteins for their ligand partners with the near-infrared fluorescence readout of SWCNTs that is modulated upon protein-ligand binding. In this manner, we demonstrate that although formation of the nanoparticle protein corona can impede the intended nanobiotechnology application, it also presents an opportunity to create improved protein-nanoparticle architectures by manipulating selective protein adsorption on the nanoparticle surface to generate nanosensors for detection of SARS-CoV 2 infections.5

References

Pinals, R.L., et al., Quantitative Protein Corona Composition and Dynamics on Carbon Nanotubes in Biological Environments. Angew Chem Int Ed Engl, 2020.doi:10.1101/2020.01.13.905356.

Pinals, R. L., Yang, D., Lui, A., Cao, W. & Landry, M. P. Corona Exchange Dynamics on Carbon Nanotubes by Multiplexed Fluorescence Monitoring. J. Am. Chem. Soc.
142, 1254–1264 (2020).

Boghossian, A. A. et al. Near-Infrared Fluorescent Sensors based on Single-Walled Carbon Nanotubes for Life Sciences Applications. ChemSusChem
4, 848–863 (2011).

Demirer, G. S. et al. High aspect ratio nanomaterials enable delivery of functional genetic material without DNA integration in mature plants. Nat. Nanotechnol.
14, 456–464 (2019).

Pinals, R., Ledesma, F., Yang, D., Jeong, S., Navarro, N., Pak, J.E., Landry, M.P. Rapid SARS-CoV-2 Detection by Carbon Nanotube-Based Near-Infrared Nanosensors. (2020) DOI: 10.1101/2020.11.02.20223404
Electrochemically Grown Energy and Power Dense Cathodes for Li and Na Ion Batteries
Authors: Patra Arghya , Zahiri Beniamin , Kwon Patrick , Kazi Omar A. , Braun Paul V
Published: July 2021

Electrochemical synthesis of materials has contributed to significant breakthroughs in materials processing by replacing high temperature, cost and energy intensive pyrometallurgical processes. Although electrodeposition as a technology for reduction of elements and alloys has been practiced since at least the 1940s, a current key and exciting question is to identify and develop electrodeposition strategies for the growth of secondary battery cathodes. Specifically, we focus on anodic electrolytic deposition methods to grow alkali-ion intercalated, layered/spinel transition metal oxide intercalation cathode systems. State-of-the-art synthesis for layered oxide cathodes for Li and Na-ion battery involves prolonged high temperature (>700°C) processing for long reaction times (~24 hours) under high oxygen pressure, followed by slurry casting after mixing with binders and additives. Here, we demonstrate an intermediate temperature (250-350°C) electrodeposition process to grow alkali ion (Li+, Na+) intercalated transition metal oxides across multiple transition metal chemistries of the Li system (orthorhombic LiMnO2, Li2MnO3, LiNixMn1-xO4, LiMn2O4, LiCoO2) and Na system (O3 and P2 NaxCoO2, O’3 NaxMnO2) in thick film form factors. Even though our cathodes are electrochemically grown at the lowest reported synthesis temperature and reaction times, they retain the key structural and electrochemical performance of the high temperature bulk synthesized analogues. The key features of this alternate high throughput cathode manufacturing technique include formation of binder-and-additive-free, tens of microns thick, >75% dense electrodeposits exhibiting near theoretical gravimetric capacity, low tortuosity, and chemical diffusion coefficient of Li+/Na+ ions. Our findings highlight the influence of the unique molten hydroxide-based solution chemistry platform and electrochemical processing parameters, on regulating the phase assemblage, designing the microstructure, and controlling crystallographic orientation during electrocrystallization.
Selective Deposition and Shear Assisted Alignment of Semiconducting Carbon Nanotubes Using Chemical and Topographical Features
Authors: Dwyer Jonathan H. , Suresh Anjali , Jinkins Katherine , Zheng Xiaoqi , Arnold Michael , Berson Arganthaël , Gopalan Padma
Published: July 2021

Selective deposition of semiconducting carbon nanotubes (s-CNTs) into densely packed, aligned arrays of individualized s-CNTs is necessary to realize their potential in semiconductor electronics. We report the combination of chemical contrast patterns, topography, and pre-alignment of s-CNTs via shear to achieve selective-area deposition of aligned arrays of CNTs. Alternate stripes of surfaces favorable and unfavorable to s-CNT adsorption were patterned with widths varying from 2000 nm down to 100 nm. When the chemical and topographical contrast patterns are reduced to less than the width of individual nanotubes (≤ 500 nm), confinement effects become dominant enabling the selective-area deposition of much more tightly aligned CNTs (~7 degrees). At a trench width of 100 nm, we demonstrate the lowest standard deviation in alignment degree of 7.6 ± 0.3° at a deposition shear rate of 4,600 s-1, while maintaining an individualized s-CNT density > 30 CNTs µm-1. Chemical contrast alone enables selective area deposition but chemical contrast in addition to topography enables more effective selective area deposition and stronger confinement effects, with the advantage of removal of nanotubes deposited in spurious areas via selective lift-off of the topographic features. These findings provide a methodology that is inherently scalable, and a means to deposit spatially selective, aligned s-CNT arrays for next-generation semiconducting devices.
(Invited) Spectroscopic Titration Shows (n,m)-Dependent Displacement of SDS By ssDNA on Single-Wall Carbon Nanotubes
Authors: Lei Kunhua , Bachilo Sergei M. , Weisman R. Bruce
Published: July 2021

Single-stranded DNA oligonucleotides (ssDNA) are uniquely customizable polymers that are useful for coating, suspending, and structurally sorting single-wall carbon nanotubes (SWCNTs) in water. However, SWCNT dispersions are instead commonly prepared using inexpensive amphiphilic surfactants such as SDS. By monitoring changes in the nanotube fluorescence wavelengths and intensities, we show that such SDS coatings on dispersed SWCNTs can be controllably displaced by the addition of small amounts of ssDNA. The displacement data can be well represented by kinetic modeling, giving the time scales for equilibration of the coating composition. We measured spectra of SWCNT samples that were dispersed in low concentrations of SDS, then treated with small amounts of ssDNA, and allowed to reach equilibrium. Plots of the final spectral shifts as a function of added ssDNA provide (n,m)-specific “titration” curves that show strongly diameter-dependent behavior. Smaller diameter nanotubes undergo SDS displacement at the lowest ssDNA concentrations. The limiting spectral shifts suggest that SWCNT surfaces become coated with adsorbed SDS as well as ssDNA. We will illustrate how the (n,m)-dependent displacements found here can be used for structural sorting of mixed SWCNT samples.
Quantum Defects As a Toolbox for the Covalent Functionalization of Carbon Nanotubes with Peptides and Proteins
Authors: Mann Florian , Herrmann Niklas , Opazo Felipe , Kruss Sebastian
Published: July 2021

Single‐walled carbon nanotubes (SWCNTs) are a 1D nanomaterial that shows fluorescence in the near‐infrared (NIR, >800 nm). In the past, covalent chemistry was less explored to functionalize SWCNTs as it impairs NIR emission. However, certain sp3 defects (quantum defects) in the carbon lattice have emerged that preserve NIR fluorescence and even introduce a new, red‐shifted emission peak. Here, we report on quantum defects, introduced using light‐driven diazonium chemistry, that serve as anchor points for peptides and proteins. We show that maleimide anchors allow conjugation of cysteine‐containing proteins such as a GFP‐binding nanobody. In addition, an Fmoc‐protected phenylalanine defect serves as a starting point for conjugation of visible fluorophores to create multicolor SWCNTs and in situ peptide synthesis directly on the nanotube. Therefore, these quantum defects are a versatile platform to tailor both the nanotube's photophysical properties as well as their surface chemistry.
(Invited) Sensing with Chirality Pure Near Infrared Fluorescent Carbon Nanotubes
Authors: Nißler Robert , Kurth Larissa , Li Han , Spreinat Alexander , Kuhlemann Ilyas , Flavel Benjamin S , Kruss Sebastian
Published: July 2021

Semiconducting single wall carbon nanotubes (SWCNTs) fluoresce in the near infrared (NIR) and the emission wavelength depends on their chirality (n,m). Interactions with the environment affect the fluorescence and can be tailored by functionalizing SWCNTs with biopolymers such as DNA, which is the basis for fluorescent biosensors. So far, such biosensors were mainly assembled from mixtures of SWCNT chiralities with large spectral overlap, which affects sensitivity as well as selectivity and prevents multiplexed sensing. The main challenge to gain chirality pure sensors has been to combine approaches to isolate specific SWCNTs and generic (bio)functionalization approaches. Here, we created chirality pure SWCNT-based NIR biosensors for important analytes such as neurotransmitters and investigated the impact of SWCNT chirality/handedness as well as long-term stability and sensitivity. For this purpose, we used aqueous two-phase extraction (ATPE) to gain chirality pure (6,5)-, (7,5)-, (9,4)- and (7,6)-SWCNTs (emission at ~ 990, 1040, 1115 and 1130 nm). Exchange of the surfactant sodium deoxycholate (DOC) to specific single-stranded (ss)DNA sequences yielded monochiral sensors for small analytes (dopamine, riboflavin, ascorbic acid, pH). DOC residues impaired sensitivity and therefore sufficient removal was necessary. The assembled monochiral sensors were up to 10 times brighter than their non-purified counterparts and the ssDNA sequence determined absolute fluorescence intensity as well as colloidal (long-term) stability and selectivity for the analytes. (GT)40-(6,5)-SWCNTs displayed the maximum fluorescence response to the neurotransmitter dopamine (+140 %, Kd = 1.9 x10-7 M) and a long-term stability > 14 days. The specific ssDNA sequences imparted selectivity to the analytes in majority of the cases independent of SWCNT chirality and handedness of (+/-) (6,5)-SWCNTs, which allows a predictable design. Finally, multiple monochiral/single-color SWCNTs were combined to achieve ratiometric/multiplexed sensing of the important analytes dopamine, riboflavin, H2O2 and pH. In summary, we demonstrated the assembly, characteristics and potential of monochiral (single-color) SWCNTs for multiple NIR fluorescent sensing applications.
(Invited) Mechanistic Study of the Covalent Bond-Mediated Charge Transfer between Carbon Nanotubes and Molecular Probes
Authors: Alphonse Fiebor , Setaro Antonio , Adeli Mohsen , Reich Stephanie
Published: July 2021

The noncovalent interaction between carbon nanotubes and molecular groups leads to hybrid systems with low stability and poorly defined structure in terms of the density of functional groups, their relative positions and orientation. Since these factors are affected by microenvironmental parameters, studying the charge transfer of such dynamic systems is challenging. Covalent attachment of molecular probes, on the other hand, disturb the π-conjugated integrity of carbon nanotubes and suppress their light emission1,2. In 2017, we explored a nondestructive covalent functionalization (NCF) that opens up new avenues to overcome the aforementioned challenges3. NCF is an effective strategy for the preparation of stable carbon nanotube hybrids with defined functionality and preserved photoluminescence property4. In this work, we have used NCF for the mechanistic study of covalent bond-mediated charge transfer between molecular probes and carbon nanotubes by manipulating the structure of the probes. Different molecular probes with the same backbone but different functionality were synthesized by reaction between aniline derivatives and cyanuric chloride (Figure 1a). The conjugation of the molecular probes to the surface of carbon nanotubes by nitrene [2+1] cycloaddition reaction resulted in hybrid systems with the preserved physicochemical properties. π conjugated system of carbon nanotubes was integrated outwards into the backbone of molecular probes upon opening the aziridine ring in the bridge position and resulted in charge transfer between these two components (Figure 1b). Due to the same chemical backbone but different number of electron donating groups, variation in the optical properties of carbon nanotubes was assigned to the contribution of these groups in doping through which a mechanism for the covalent bond-mediated charge transfer was proposed. As a proof of concept, we have demonstrated a new way to forward the π conjugated system of carbon nanotubes outwards into other (macro)molecules which results in new systems with the unique optoelectronic properties.

References

Cognet, L. et al. Science
2007, 316, 1465.

Piao, Y. et al. Chem.
2013, 5, 840.

Setaro et al. Nat Commun.
2017, 8, 14281.

Godin et al. Science Advances, 2019, 5, eaax116.

Figure 1
(Invited) Different Pathways of Fluorescent SWCNT Modifications with Aromatic Reactants
Authors: Bachilo Sergei M. , Weisman R. Bruce , Zheng Yu
Published: July 2021

Modification of electronic and chemical properties of single-wall carbon nanotubes (SWCNTs) by covalent side-wall functionalization can produce a stable material with purposely-enhanced electronic and optical properties. In the report we describe a new type of reactions between simple aromatic compounds and SWCNTs, creating different fluorescent trapping states in SWCNTs. The photoreactions take place in aqueous suspensions of SWCNTs with small addition of soluble or even very-slightly soluble organic aromatic compounds excited by UV light. The reaction rates depend on the aromatic compound structure and proportional to its concentration, and in some cases, as with aniline or iodoaniline, new strong and well-resolved spectral sidebands appear within one minute. Total SWCNT photoluminescence intensity can increase, and the increase was in some cases by a factor of 5 as compare to original species. The shifted emission bands and the trapping nature of them, when the main part of the nanotube is performing as an absorbing antenna delivering excitation energy to the modified sites, may be interesting for a variety of optical and electronic applications.

Most notably, in most cases of these photochemical reactions, the shifted emission spectra from modified SWCNTs become different, displaying never observed previously structure upon removal of molecular oxygen from the solution. For instance, treatment with normal dissolved oxygen gives a rise to a new emission band red-shifted for (6,5) SWCNTs by 160 meV from the pristine position, which is similar to many previously studied reactions starting with oxygen doping. Corresponding results will appear for other species as well. However, if the molecular oxygen is removed from the suspension by degassing or gas substitution, same UV treatments will lead to two different emission bands red-shifted by 140 and 270 meV, one less shifted and one more shifted, thus indicating different chemical products of the reactions. These new bands grow with different rate under UV illumination. Variance spectroscopy of such samples shows the presence of individual “multicolor” nanotubes with three distinct emission bands, one original/unmodified plus two shifted. The reaction demonstrates new possibilities for creation different trapping states on individual nanotubes, and opens new options for tuning electronic and optical properties of nanotubes for possible applications.
Organic Color Center Platform for Cancer Diagnosis
Authors: Kim Mijin , Yang Yoona , Wang Peng , Chen Chen , Antman-Passig Merav , Wun Christopher , Luo Hong-bin , Wang YuHuang , Jagota Anand , Zheng Ming , Heller Daniel A.
Published: July 2021

Organic color centers (OCC), synthetic defects incorporated into single-walled carbon nanotubes, feature extraordinary traits that make them an ideal platform for biochemical sensing applications. The OCC-induced fluorescence peak is tunable and extremely sensitive to the local microenvironment around the covalent functional group. Depending on the chemical nature of the functional group that induces each OCC, the fluorescence features can be systematically controlled. Based on the chemical tunability and sensitivity of OCCs, we construct OCC-based nanosensors that enables multiplexed sensing of bioanalytes in serum. The diverse spectral responses, processed by data analytics, enables disease identification.
(Invited) Machine Learning for DNA/SWCNT Based Molecular Perceptron: Finding Sequences and Training Sensor Arrays
Authors: Yang Yoona , Yaari Zvi , Lin Zhiwei , Sharma Arjun , Heller Daniel A. , Zheng Ming , Jagota Anand
Published: July 2021

Single wall carbon nanotube (SWCNT) based biosensors provide opportunities for building an ultra-sensitive biosensing system due to their unique optical properties and strong sensitivity to changes in the local environment. Consequently, much effort has been made to develop SWCNT-based sensors. However, the usual method is based on one-to-one recognition which is a difficult way to detect a variety of molecules. In this study, we describe a sensing system that uses an array of weakly-specific sensors combined with a machine learning model, which we call the Molecular Perceptron. We show how machine learning algorithms, along with choice of feature representation, can be used both for discovery of special resolving DNA sequences and to predict presence and concentration of biomarkers. DNA/SWCNT hybrids were utilized to optically detect biomarker analytes by observing changes in the fluorescence spectra of each SWCNT. Using the experimental data, machine learning models were trained using three different algorithms: Support Vector Machine, Random Forest, and Artificial Neural Network. We also demonstrate that machine learning models trained on relatively small DNA sequence data sets can very accurately predict new resolving DNA sequences
(Invited) Photoresponsive Multiplexed Carbon Nanotube-Hybrid Nanoscale Devices
Authors: Ye Qingyu , Xu Xinzhao , Dimitrov Stoichko , Palma Matteo
Published: July 2021

By synergistically combining the individual properties of more than one nanoscale component, research efforts on hybrid structures assembly and their features represent a key motivation for making future functional nanomaterials. In this regard, we developed different platforms based on the in-solution assembly of classes of molecular materials (organic, inorganic, and biological with promising attributes) to single-walled carbon nanotubes (SWCNTs), employed as building blocks that allow for nanoscale studies to be performed in a variety of research fields.[1-7]

In this talk, we will present a one-pot assembly strategy for the construction in aqueous solution of hybrid nanostructures comprising inorganic semiconducting nanoparticles (CdS and PbS) grown on carbon nanotubes templates, and their organization in multiplexed nanoscale devices exhibiting photoinduced electrical response.[8] The electrical response observed suggests different processes within the hybrids, depending on the inorganic material employed, i.e. CdS or PbS. We investigated the behaviour of the hybrids via transient absorption spectroscopy, which further cast light on the different photoresponses of our devices.[8] The strategy we developed is of general applicability for the controlled fabrication of CNT-based multiplexed photoresponsive optoelectronic hybrid systems and devices.

[1] Journal of the American Chemical Society, 2016, 138, 2905-2908

[2] Angewandte Chemie International Edition, 2019, 2019, 59, 9928-9932

[3] Small, 2017, 13, 1603042

[4] Advanced Science, 2018, 5, 1800596

[5] Chemistry of Materials, 2019, 31, 1537-1542

[6] Journal of the American Chemical Society, 2017, 139, 17834-17840

[7] Nano Letters, 2018, 18, 4130-4135

[8] Submitted
(Invited) Empirical Modeling of Broadband Complex Optical Spectra of Single-Chirality-Enriched Carbon Nanotube Films for Optical Design
Authors: Nishihara Taishi , Takakura Akira , Matsuda Kazunari , Tanaka Takeshi , Kataura Hiromichi , Miyauchi Yuhei
Published: July 2021

Exceptional optical properties of single-walled carbon nanotubes (SWCNTs) potentially provide various promising applications including photonic and thermo-optic [1] devices. However, systematic knowledge on the broadband optical spectra of macroscopic films composed of single-chirality-enriched SWCNTs [2] has still been limited. We will report an empirical model of the broadband complex optical spectra of single-chirality-enriched SWCNTs films, as can be readily used by engineers for optical design. [1] T. Nishihara, A. Takakura, Y. Miyauchi, and K. Itami, Nat. Commun. 9, 3144 (2018). [2] Y. Yomogida, T. Tanaka, M. Zhang, M. Yudasaka, X. Wei, and H. Kataura, Nat. Commun. 7, 12056 (2016).
(Invited) Understanding the Process Variables to Achieve Global Alignment of Single-Wall Carbon Nanotubes
Authors: Rust Christian , Li Han , Spari Manuel , Guttmann Markus , Flavel Benjamin S
Published: July 2021

Carbon nanotubes (CNTs) are a 1D dimensional material with anisotropy in their thermal, electronic and optical properties. It is therefore a grand challenge to control their orientation in an ensemble and prepare large scale aligned thin-films. In this direction, slow flow dead-end filtration using polyvinylpyrrolidone-coated polycarbonate membranes has recently been shown to achieve global alignment of CNTs across an entire membrane. This route is highly attractive because it allows for purified dispersions to be used but it has proven to be difficult to reproduce. In this work, we present a custom dead-end filtration setup capable of precise in-situ measurement of flow, trans-membrane pressure and effective retention. This setup allows us to identify the important variables to achieve global alignment and explain why others have found it hard to reproduce in their own laboratory.
(Invited) Theoretical Insights into New Strategies of Carbon Nanotube Functionalization
Authors: Tretiak Sergei
Published: July 2021

An intentional introduction of quantum defects to the carbon nanotube surface leads to unique photoluminescence properties that may be useful for a wide range of optoelectronic, sensing, imaging and quantum communication applications. Quantum-chemical simulations help to rationalize spectroscopic observation and fine tune synthetic strategies. I will overview modeling results analyzing emergent optical behavior spatially patterned covalent functionalization achieved by reaction with single-stranded DNA. Here strongly interacting multiple guanine defects within a single ssDNA strand form an extended trapping potential well that contains multiple excitonic states, leading to monotonic variation of the emission wavelength. Another synthetic strategy is utilization of singlet- and triplet- pathways in aromatic photochemistry leading to a surprising versatility of the products. Calculations help understanding precise chemistry of binding at atomic and single-bond level that leads to the control of different binding configurations
Additive-Free Solution Processing of Carbon Nanotubes in Industrial Solvents
Authors: Huang Jiaxing
Published: July 2021

Carbon nanotubes can now be produced in the ton scale in the form of powders, but they need to be further processed, usually by solution-based routes, into disaggregated and more usable forms for applications. There has been extensive effort to search and design solvents that can disperse nanotubes, which can also be easily removed afterward. We have discovered that cresols, which are already manufactured for other industrial purposes, are such solvents. They can disperse carbon nanotube powders of many types at unprecedentedly high concentrations, rendering them polymer-like rheological and viscoelastic properties, and high processability. This makes carbon nanotube powders immediately usable by current materials-processing techniques for creating desirable structures or composites.

Using cresols as a minority cosolvent, unfunctionalized carbon nanotubes can be dispersed in many common industrial solvents. Spectroscopic studies reveal that cresol forms a charge-transfer complex with carbon nanotubes, which is destabilized in high-dielectric-constant solvents but remains stable in low-dielectric-constant solvents. The new chemical insight enables scalable technical solutions for solving a longstanding problem of solution processing of carbon nanotubes. For example, volatile compatible solvents, such as n-hexane and chloroform, can be used as the main solvent to formulate fast-evaporating nanotube inks for high-throughput techniques, such as airbrushing, to quickly create continuous and conformal carbon nanotube coatings. Meanwhile, incompatible solvents such as acetone can help remove residual high-boiling-point cresols without the usual need for heating.