Second harmonic generating (SHG) nanoprobes have recently emerged as versatile and durable labels suitable for in vivo imaging, circumventing many of the inherent drawbacks encountered with classical fluorescent probes. Since their nanocrystalline structure lacks a central point of symmetry, they are capable of generating second harmonic signal under intense illumination – converting two photons into one photon of half the incident wavelength – and can be detected by conventional two‐photon microscopy. Because the optical signal of SHG nanoprobes is based on (...) scattering, rather than absorption as in the case of fluorescent probes, they neither bleach nor blink, and the signal does not saturate with increasing illumination intensity. When SHG nanoprobes are used to image live tissue, the SHG signal can be detected with little background signal, and they are physiologically inert, showing excellent long‐term photostability. Because of their photophysical properties, SHG nanoprobes provide unique advantages for molecular imaging of living cells and tissues with unmatched sensitivity and temporal resolution. (shrink)

Plant cell culture systems have become an attractive and sustainable approach to produce high‐value and commercially significant metabolites under controlled conditions. Strategies involving elicitor supplementation into plant cell culture media are employed to mimic natural conditions for increasing the metabolite yield. Studies on nanoparticles (NPs) that have investigated elicitation of specialized metabolism have shown the potential of NPs to be a substitute for biotic elicitors such as phytohormones and microbial extracts. Customizable physicochemical characteristics allow the design of monodispersed‐, stimulus‐responsive‐, (...) and hormone‐carrying‐NPs of precise geometries to enhance their elicitation capabilities based on target metabolite/plant cell culture type. We contextualize advances in NP‐mediated elicitation, especially stimulation of specialized metabolic pathways, the underlying mechanisms, impacts on gene regulation, and NP‐associated cytotoxicity. The novelty of the concept lies in unleashing the potential of designer NPs to enhance yield, harness metabolites, and transform nanoelicitation from exploratory investigations to a commercially viable strategy. (shrink)

The risks of materials containing nanoscale components are in the public debate discussed as if a manufactured nanomaterial will remain invariant with time and environmental exposure, and as if we can identify its risks by the risks of its nanoscale components. Additionally, the debate on mitigation of specific nanorisks by new legislation implicitly assumes that we can have full and accurate knowledge of the distribution and composition of nanomaterials in a product or the environment. In this discussion note, I argue (...) that physical laws intrinsic to the behavior of nanoparticles both lead to limits on the risks to which we are likely exposed and on our technological ability to verify compliance with new regulations. My conclusion is that governmental actors should be careful not to overreact in their response to a technological revolution that only in few areas is likely to lead to increased public exposure, and in doing so using legal measures for which compliance cannot be monitored. (shrink)

Much contemporary nanotoxicology, nanotherapeutic and nanoregulatory research has been characterised by a focus on investigating how delivery of engineered nanoparticles (ENPs) to cells is dictated primarily by components of the ENP surface. An alternative model, some implications of which are discussed here, begins with fundamental physicochemical research into the interaction of a dynamic nanoparticle-protein corona (NPC) with biological systems. The proposed new model also requires, however, that any such fresh NPC physicochemical research approach should involve integration and targeted collaboration (...) from the earliest stages with nanotoxicology, nanotherapeutics and nanoregulatory expertise. The justification for this integrated approach, we argue, relates not just to efficiency and promotion of innovation, but to an acknowledgement that public-funded basic physicochemical research in particular should now be accepted to incorporate strong higher order public goods elements from its inception, not merely after product development at the technology transfer stage. Issues, in other words, such as university research co-operation, commercialization and intellectual property (IP) protection, safety and cost-effectiveness regulatory assessment, as well as technology transfer should not be viewed as second tier considerations even in a ‘blue sky’ NPC basic research agenda. (shrink)

Nanomaterials have attracted much interest in the medical field and related applications as their distinct properties in the nanorange enable new and improved diagnosis and therapies. Owing to these properties and their potential interactions with the human body and the environment, the impact of nanomaterials on humans and their potential toxicity have been regarded a very significant issue. Consequently, nanomaterials are the subject of a wide range of cutting-edge research efforts in the medical and related fields to thoroughly probe their (...) potential beneficial utilizations and their more negative effects. We posit that the lack of standardization in the field is a serious shortcoming as it has led to the establishment of methods and results that do not ensure sufficient consistency and thus in our view can possibly result in research outputs that are not as robust as they should be. The main aim of this article is to present how NanoDiaRA, a large FP7 European multidisciplinary project that seeks to investigate and develop nanotechnology-based diagnostic systems, has developed and implemented robust, standardized methods to support research practices involving the engineering and manipulation of nanomaterials. First, to contextualize this research, an overview of the measures defined by different regulatory bodies concerning nanosafety is presented. Although these authorities have been very active in the past several years, many questions remain unanswered in our view. Second, a number of national and international projects that attempted to ensure more reliable exchanges of methods and results are discussed. However, the frequent lack of publication of procedures and protocols in research can often be a hindrance for sharing those good practices. Subsequently, the efforts made through NanoDiaRA to introduce standardized methods and techniques to support the development and utilization of nanomaterials are discussed in depth. A series of semi-structured interviews were conducted with the partners of this project, and the interviews were analyzed thematically to highlight the determined efforts of the researchers to standardize their methods. Finally, some recommendations are made toward the setting up of well-defined methods to support the high-quality work of collaborative nanoparticle-based research and development projects and to enhance standardization processes. (shrink)

Scientific writings and policy documents define the terms nanomaterial and nanoparticle in various ways. This variation is considered problematic because the absence of a shared definition is understood as potentially hindering nanomaterial knowledge production and regulation. Another view is that the existence of a shared definition may itself cause problems, as rigid definitions arguably exclude important aspects of the studied phenomena. The aim of this paper is to inform this state of disagreement by providing analytical concepts for a systematic understanding (...) of how, and even whether, nanomaterial and nanoparticle could and should be defined. To do this, we review definitions of nanomaterial and nanoparticle presented in research articles and policy documents. Definitions were identified by first conducting a Scopus search and then tracing cited definitions back to their sources. In total, 36 definitions were identified. Theories of definition from philosophy and linguistics provide analytical guidance for structuring and categorizing the identified definitions, and the main analytical dimensions of the definitions are then identified and discussed. Finally, we propose a framework for understanding the process of defining nanomaterial and nanoparticle. This framework considers both the generality needed for a shared understanding and the level of precision required for different purposes. (shrink)

A method is presented to compute the electron-optical phase shift for a magnetized polyhedral nanoparticle, with either a uniform magnetization or a closure domain . The method relies on an analytical expression for the shape amplitude, combined with a reciprocal-space description of the magnetic vector potential. The model is used to construct two building blocks from which more complex structures can be generated. Phase computations are also presented for the five Platonic and 13 Archimedean solids. Fresnel and Foucault imaging mode (...) simulations are presented for a range of particle shapes and microscope imaging conditions. (shrink)

The article analyses European regulations concerning the health protection at work with nanomaterials in the context of the Christian vision of human work. The increasingly widespread presence of nanotechnology in workplaces requires serious reflection on the adequacy of employers’ measures to protect workers’ health from the risks in the workplace. The lack of clear guidance in European legislation directly concerning work with nanoparticles is problematic. Moreover, the health consequences for workers using nanomaterials in the work process are not fully (...) explored in science. It is therefore essential to consider what values should accompany employers in shaping working conditions and what values should be legislated when creating occupational health and safety law. First of all, how should the employers deal with the unknown? Should they abandon nanomaterials for which they do not have adequate information at all until the consequences for workers’ health have been established? Should such action be limited to situations where studies indicate the toxicity of the nanomaterials present in the working environment? In this context, the article analyses values and objectives indicated by the teaching of the Catholic Church. The publication presents a Christian vision on the protection of workers’ health and their place in the work process. Europe has been under the influence of Christianity for many centuries now. The Catholic Church’s view of human labour continues to be present in public debates in Europe. The Christian view of human labour is focused on the working man and his dignity. Irrespective of other concepts of labour, Christianity assumes the priority of a human being over capital. The Catholic Church analyses the working man as going beyond the Earthly context, which is not typical for such doctrines as liberalism or Marxism. The author’s article is an attempt in answering the question about how up to date the Catholic Church’s views on human labour are in the light of nanotechnology development in the workplace. (shrink)

The ‘Precautionary Principle’ provides a somewhat ill-defined guide, often of uncertain normative status, for those exercising administrative decision-making power in circumstances where that may create potential risks to human health or the environment. This paper seeks to explore to what extent the precautionary principle should have been and was in fact utilised by the Australian Therapeutic Goods Administration (TGA) in its decision to approve the marketing of sunscreens containing titanium dioxide (TiO2) and zinc oxide (ZnO) in nanoparticulate form. In particular, (...) this article assesses to what extent better application of that principle might have altered the TGA’s decision that TiO2 and ZnO ENPs in sunscreens do not require new safety testing, because they are considered to be functionally equivalent to their bulk counterparts. (shrink)

The NANOCAN project aims to enhance our understanding of the behavior of nanomaterials in the body, focusing on biodegradable nanoparticles for cancer diagnostics, and targeted cancer drug delivery. There is a range of available and potentially useful nanoparticles and drugs that might be of interest to such a project. In this paper, we make values implied in—and relevant to—choices between these alternatives explicit, thereby offering a case study of how values enter research processes in this area. From a (...) project centered perspective, we observe that values often play their role implicitly, as a result of funding incentives, regulations, and structural and organizational features of the research process. Based on our observations and categorization of relevant values, we turn to a broader discussion of how responsible research and innovation can be facilitated by making value priorities, value conflicts, and biases explicit targets of normative assessment. (shrink)

The electron-optical phase shift induced in the electron beam due to the interaction with the electromagnetic field of magnetized nanoparticles of defined shape and arbitrary dimensions is calculated, presented and discussed. Together with the computable knowledge of vector potential and magnetic induction, including the demagnetizing field, and with the extension to more realistic geometries which will be presented in part II, this theoretical framework can be employed for the interpretation of transmission electron microscopy experiments on magnetic particles on the (...) nanometre scale. (shrink)

The diversity of nanotechnologies and of the governance challenges that their applications raise calls for exploration and learning across different cases. We present an Upstream Oversight Assessment (UOA) of expected benefits and potential harms of nanoparticles made of a synthetic polymer (PLGA) to improve vaccines for farmed salmon. Suggested by Jennifer Kuzma and colleagues, an UOA may help identify and prioritise research needs, and it may support evaluations of the adequacy of relevant existing regulatory frameworks. In this work, the (...) UOA approach is modified and supported with elements from the uncertainty analysis framework developed by Warren Walker and colleagues. Empirically, we draw on relevant available published literature and insights generated in an ongoing nanoparticle salmon vaccine project, in which one of the authors participates. Nanotechnologies have not previously been encountered in the regulatory context of fish vaccines, which in part raises unique challenges due to prospective large scale vaccine use in semi-open aquatic systems. Strengthened through cooperation between ELSA and technology researchers we found the UOA useful for an early mapping of benefits and concerns, and for identifying areas in need of further research prior to a nanoparticle based salmon vaccine is developed and taken into use. We consider our approach to represent one among several complementing initiatives that seek to contribute to early stage evaluations of possible negative side effects, broadly conceived, in order to facilitate a more robust nanotechnology development. (shrink)

Nanoparticles have multifaceted advantages in drug administration as vaccine delivery and hence hold promises for improving protection of farmed fish against diseases caused by pathogens. However, there are concerns that the benefits associated with distribution of nanoparticles may also be accompanied with risks to the environment and health. The complexity of the natural and social systems involved implies that the information acquired in quantified risk assessments may be inadequate for evidence-based decisions. One controversial strategy for dealing with this (...) kind of uncertainty is the precautionary principle. A few years ago, an UNESCO expert group suggested a new approach for implementation of the principle. Here we compare the UNESCO principle with earlier versions and explore the advantages and disadvantages by employing the UNESCO version to the use of PLGA nanoparticles for delivery of vaccines in aquaculture. Finally, we discuss whether a combined scientific and ethical analysis that involves the concept of responsibility will enable approaches that can provide a supplement to the precautionary principle as basis for decision-making in areas of scientific uncertainty, such as the application of nanoparticles in the vaccination of farmed fish. (shrink)

While nanosciences and nanotechnologies appear as new concepts developed at the end of the twentieth century, we show that metallic nanoparticles have already been used since ancient times, in particular as colorant in the glass and ceramic industries. Moreover, a lot of natural nanomaterials are also present in the mineral, vegetal and animal worlds. Nevertheless, the breakthrough of nanotechnology has been permitted in the past few decades by the advent of apparatus allowing the manipulation and observation of the nanoworld. (...) Indeed, nowadays, nanomaterials and nanoparticles are used for many applications in our daily life, such as in the fields of electronics, catalysis, optics, biology, and medicine. This article presents an overview about nanotechnologies, with applications from ancient times till the present. (shrink)

Nanoparticles of cobalt ferrite prepared by the co-precipitation method with crystallite size varying from 4.7 to 41 nm have been characterized by positron annihilation lifetime spectroscopy. Three lifetime components are fitted to the lifetime data. The shortest lifetime component is attributed to the delocalized positron lifetime shortened by defect trapping. The intermediate lifetime is assigned to the positron annihilation in diffuse vacancy clusters or microvoids at the grain boundaries and at the grain-boundary triple points. The longest component corresponds to (...) the pick-off annihilation of ortho-positronium formed at the larger voids. The variations in these lifetimes and their relative intensities with annealing temperature and crystallite size have been studied in detail. (shrink)

Nanomedicine is yielding new and improved treatments and diagnostics for a range of diseases and disorders. Nanomedicine applications incorporate materials and components with nanoscale dimensions where novel physiochemical properties emerge as a result of size-dependent phenomena and high surface-to-mass ratio. Nanotherapeutics and in vivo nanodiagnostics are a subset of nanomedicine products that enter the human body. These include drugs, biological products, implantable medical devices, and combination products that are designed to function in the body in ways unachievable at larger scales. (...) Nanotherapeutics andin vivonanodiagnostics incorporate materials that are engineered at the nanoscale to express novel properties that are medicinally useful. These nanomedicine applications can also contain nanomaterials that are biologically active, producing interactions that depend on biological triggers. Examples include nanoscale formulations of insoluble drugs to improve bioavailability and pharmacokinetics, drugs encapsulated in hollow nanoparticles with the ability to target and cross cellular and tissue membranes and to release their payload at a specific time or location, imaging agents that demonstrate novel optical properties to aid in locating micrometastases, and antimicrobial and drug-eluting components or coatings of implantable medical devices such as stents. (shrink)

Nanomedicine plays a prominent role among emerging technologies. The spectrum of potential applications is as broad as it is promising. It includes the use of nanoparticles and nanodevices for diagnostics, targeted drug delivery in the human body, the production of new therapeutic materials as well as nanorobots or nanoprotheses. Funding agencies are investing large sums in the development of this area, among them the European Commission, which has launched a large network for life-sciences related nanotechnology. At the same time (...) government agencies as well as the private sector are putting forward reports of working groups that have looked into the promises and risks of these developments. This paper will begin with an introduction to the central ethical themes as identified by selected reports from Europe and beyond. In a next step, it will analyse the most frequently invoked ethical concerns–risk assessment and management, the issues of human identity and enhancement, possible implications for civil liberties (e.g. nanodevices that might be used for covert surveillance), and concerns about equity and fair access. Although it seems that the main ethical issues are not unique to nanotechnologies, the conclusion will argue against shrugging them off as non-specific items that have been considered before in the context of other biomedical technologies, such as gene therapy or xenotransplantation. Rather, the paper will call on ethicists to help foster a rational, fair and participatory discourse on the different potential applications of nanotechnologies in medicine, which can form the basis for informed and responsible societal and political decisions. (shrink)

The promises of nanotechnology have been framed by a variety of metaphors, that not only channel the attention of the public, orient the questions asked by researchers, and convey epistemic choices closely linked to ethical preferences. In particular, the image of the ‘therapeutic missile’ commonly used to present targeted drug delivery devices emphasizes precision, control, surveillance and efficiency. Such values are highly praised in the current context of crisis of pharmaceutical innovation where military metaphors foster a general mobilization of resources (...) from multiple fields of cutting-edge research. The missile metaphor, reminiscent of Paul Ehrlich’s ‘magic bullet’, has framed the problem in simple terms: how to deliver the right dose in the right place at the right moment? Chemists, physicists and engineers who design multi-functional devices operating in vitro can think in such terms, as long as the devices are not actually operating through the messy environment of the body. A close look at what has been done and what remains to be done suggests that the metaphor of the “therapeutic missile” is neither sufficient, nor even necessary. Recent developments in nanomedicine suggest that therapeutic efficacy cannot be obtained without negotiating with the biological milieu and taking advantage of what it affords. An ‘oikological’ approach seems more appropriate, more heuristic and more promising than the popular missile. It is based on the view of organism as an oikos that has to be carefully managed. The dispositions of nanocapsules have to be coupled with the affordances of the environment. As it requires dealing with nanoparticles as relational entities (defined by their potential for interactions) rather than as stable substances (defined by intrinsic properties) this metaphor eventually might well change research priorities in nanotechnology in general. (shrink)

This series of images forms part of the ongoing project Soft Ground, Hard Light, which speculates on a multiscalar spatial ontology of photography emanating from the Arditurri silver mine complex in the Basque Country. Evoking the mountainous massif around Arditurri where silver ore and galena have been extracted since Roman presence in the area, the depicted topographies are, in fact, data transcriptions from atomic force microscopy (AFM) probing the analogue film stock of an early 1930s experiment in 3D cinema, Cine (...) en Relieve, by the Basque cinematographer Teófilo Mingueza. In contrast to optical or electron microscopy, AFM uses a scanning probe to physically touch the specimen, recording its surface undulations at the atomic scale of a nanometre, or a billionth of a metre. As a haptic operation based on direct contact between instrument and sample, between apparatus and referent, AFM is literally a contact print, a ‘blind’ scan that senses not the visual content of the recorded image but ‘feels’ its underlying material substrate of silver nanoparticles within the 35 mm film emulsion. The resulting image assemblies visualize a topography resulting from the intra-action between the silver nanoparticles and the scanning probe as much as its transcription through the particular parameters afforded by the AFM analysis software. Hard Light, Soft Ground was initiated during an artist’s residency at Tabakalera Centre for Contemporary Culture, Donostia-San Sebastián, and is currently in production as part of the wider research project Esper Syndrome: Archaeotopologies of the Image at the Royal College of Art, funded by the AHRC through the London Arts & Humanities Partnership. With additional thanks to the Basque Film Archive and Gustavo Ariel Schwartz at the Materials Physics Centre, Donostia-San Sebastián. (shrink)

The present study addresses the fluid transport behaviour of the flow of gold -copper /biomagnetic blood hybrid nanofluid in an inclined irregular stenosis artery as a consequence of varying viscosity and Lorentz force. The nonlinear flow equations are transformed into dimensionless form by using nonsimilar variables. The finite-difference technique is involved in computing the nonlinear transport dimensionless equations. The significant parameters like angle parameter, the Hartmann number, changing viscosity, constant heat source, the Reynolds number, and nanoparticle volume fraction on the (...) flow field are exhibited through figures. Present results disclose that the Lorentz force strongly lessens the hybrid nanofluid velocity. Elevating the Grashof number values enhances the rate of blood flow. Growing values of the angle parameter cause to reduce the resistance impedance on the wall. Hybrid nanoparticles have a superior wall shear stress than copper nanoparticles. The heat transfer rate is amplifying at the axial direction with the growing values of nanoparticles concentration. The applied Lorentz force significantly reduces the hybrid and unitary nanofluid flow rate in the axial direction. The hybrid nanoparticles expose a supreme rate of heat transfer than the copper nanoparticles in a blood base fluid. Compared to hybrid and copper nanofluid, the blood base fluid has a lower temperature. (shrink)

In recent years, in the UK and elsewhere, scientists and science policymakers have grappled with the question of how to reap the benefits of nanotechnologies while minimising the risks. Having recognised the importance of public support for future innovations, they have placed increasing emphasis on ‘engaging’ ‘the public’ during the early phase of technology development. Meaningful engagement suggests some common ground between experts and lay publics in relation to the definition of nanotechnologies and of their benefits and risks. However, views (...) on nanotechnologies are likely to vary according to where actors stand in the technology production/consumption/assessment cycle. Drawing on data from a recent UK-based study, this article examines how scientists (‘upstream’ and ‘downstream’) and policymakers portray the benefits and risks of nanotechnologies, particularly as they relate to two major areas of predicted application, namely medicine/public health and environmental sustainability. The findings reveal that, in the main, scientists and science policymakers held a positive conception of nanotechnologies and see imminent applications, although they acknowledged particular risks, including adverse public reaction. While definitions of ‘benefit’ and ‘risk’ varied, most saw the benefits as outweighing the risks and believed that the risks could be adequately regulated once they were assessed. The difficulties of assessing risk, however, were acknowledged. The study raises a number of questions that will need to be addressed if regulations are to be developed that not only protect people’s heath and wellbeing and the environment but also engender public trust in nanotechnologies. (shrink)

In this paper we will argue that the categories of physical individuals and chemical stuff are not sufficient to face the chemical ontology if nanomaterials are taken into account. From a perspective that considers ontological questions and wonders which the items involved in science are, we will argue that the domain of nanoscience must be considered as populated by entities that are neither individuals, as those of physics, nor stuff, as those items of macro-chemistry. This discussion, in virtue of the (...) analysis of the nature of nanomaterials, leads to propose a proper ontological category for nanoparticles: nanoindividuals. Nanomaterials are sorts of individuals, but they are different from physical individuals and from chemical stuff. We will also claim to contribute to the growing field of the philosophy of chemistry, especially regarding discussions that manifest not only epistemological but also ontological issues. In this scenario, the field on nanoscience is particularly challenging. (shrink)