Array-based System Research Articles

A system on chip for automatic karyotyping system

The Automatic karyotyping System is a computer-aided tool that automates the chromosome analysis and karyotyping processes, manually performed in most cytogenetic laboratories. Artificial neural networks (ANNs) have been widely used in chromosome classification due to their parallelism that reduces the computational complexity and time. However, existing classifiers are software-based, running on a computer that transforms the parallelism features of the ANNs into serial operations, thus significantly reducing their computing power. To efficiently address the above issue due to software implementation, we propose a Field-Programmable Gate Array-based System on Chip (SoC) architecture for human chromosome classification. The hardware implementation of such system can achieve the parallelism inherent to ANNs while reducing the power consumption and circuit size, thus the cost of designing such a system is reduced. The achieved part concerns the classification subsystem based on Kohonen neural network, which has been successfully tested on FPGA platform.

Colorimetric sensor array-based artificial olfactory system for sensing Chinese green tea’s quality: A method of fabrication

ABSTRACTTea quality is often evaluated by experienced tea tasters; however, their assessments are subjective, being influenced by their individual physiological and psychological condition. Herein, we fabricated a colorimetric sensor array-based artificial olfactory system for sensing the quality of Chinese green tea. First, the colorimetric sensors array was man-made using printing 12 chemically responsive dyes (9 porphyrins, metalloporphyrins and 3 pH indicators) on silica-gel flat plate. The plate was exposed to volatile organic compounds, and the colour changes in each sample were obtained by distinguishing between the images of sensor array before and after contact with tea sample. The values of colour composition changes were extracted from the dyes’ colour sections. Multivariate calibrations were applied through principal component analysis and back propagation artificial neural network (BP-ANN) for modelling. The optimum BP-ANN model was obtained with nine principal components, and the discrimination rate was equal to 85% and 86% in the calibration and prediction sets, respectively. We thus conclude that the low cost colorimetric sensor array-based artificial olfactory technique has great potential for application in intelligent evaluation of the quality of green tea.

Enhanced immunization via dissolving microneedle array-based delivery system incorporating subunit vaccine and saponin adjuvant.

PurposeTo enhance the immunogenicity of the model subunit vaccine, ovalbumin (OVA) was combined with platycodin (PD), a saponin adjuvant. To reduce the toxicity of PD, OVA, and adjuvant were loaded together into liposomes before being incorporated into a dissolving microneedle array.MethodsOVA- and PD-loaded liposomes (OVA-PD-Lipos) were prepared using the film dispersion method. Their uptake behavior, toxicity to mouse bone marrow dendritic cells (BMDCs), and hemolytic activity to rabbit red blood cells (RBCs) were evaluated. The OVA-PD-Lipos were incorporated into a dissolving microneedle array. The chemical stability of OVA and the physical stability of OVA-PD-Lipos in microneedle arrays were investigated. The immune response of Institute of Cancer Research mice and potential skin irritation reaction of rabbits to OVA-PD-Lipos-MNs were evaluated.ResultsThe uptake of OVA by mouse BMDCs was greatly enhanced when OVA was prepared as OVA-PD-Lipos, and in this form, the toxicity of PD was dramatically reduced. OVA was chemically stable as OVA-PD-Lipos, when OVA-PD-Lipos was incorporated into a dissolving microneedle array. Institute of Cancer Research mice treated with OVA-PD-Lipos-MNs showed a significantly enhanced immune response. PD combined with OVA elicited a balanced Th1 and Th2 humoral immune response in mice, with minimal irritation in rabbit skin.ConclusionThe dissolving microneedle array-based system is a promising delivery vehicle for subunit vaccine and its adjuvant.

A graphene-based chemical nose/tongue approach for the identification of normal, cancerous and circulating tumor cells

The development of reliable, cost-effective, and sensitive detection and monitoring assays is particularly important for the early diagnosis and treatment of cancer. Here, we report an array-based system for cell sensing using a ‘chemical nose/tongue’ approach that exploits subtle changes in the physicochemical nature of different cell surfaces. A family of synthetic and biomolecular functionalized graphene elements was used to develop the sensing array. Their different interactions with dissimilar cell surfaces were transduced to an ultrasensitive electrochemical impedance signal, providing a fingerprint for the classification and identification of different cells. This electrochemical array sensing platform has ultrahigh sensitivity that can detect a single-cell type from one cell. Furthermore, it can discern different cell types at levels as low as 100 cells with high accuracy for (i) different cell types; (ii) cancerous, multidrug-resistant cancerous and metastatic human breast cells; and (iii) artificial circulating tumor cells (CTCs). The graphene-based electrochemical sensing platform presented here can more generally be applied to array sensor fabrication and can provide highly efficient signal transduction pathways to improve the detection response of each recognition element.

Technical and Economical Evaluation on the Use of Reconfiguration Systems in Some EU Countries for PV Plants

This paper shows the technical and economical evaluation of the application of a reconfiguration system for photovoltaic (PV) plants, considering the incentives system in some European Union countries. The reconfiguration system is an alternative to the distributed maximum power point tracking technique which used to increase the power production in the PV plants under the mismatch phenomenon. The reconfiguration techniques employ a microprocessor-based or field-programmable gate array-based system that modifies the layout of the PV plant through the change of the connections among modules. After having presented the main features working of the PV reconfiguration system allowing the improvement of the efficiency of the same plant and the relevant installation, the main strength and weakness points of the investment are evidenced in relation to different incentives policies in some country of UE.

Scalable Parallel Distributed Coprocessor System for Graph Searching Problems with Massive Data

The Internet applications, such as network searching, electronic commerce, and modern medical applications, produce and process massive data. Considerable data parallelism exists in computation processes of data-intensive applications. A traversal algorithm, breadth-first search (BFS), is fundamental in many graph processing applications and metrics when a graph grows in scale. A variety of scientific programming methods have been proposed for accelerating and parallelizing BFS because of the poor temporal and spatial locality caused by inherent irregular memory access patterns. However, new parallel hardware could provide better improvement for scientific methods. To address small-world graph problems, we propose a scalable and novel field-programmable gate array-based heterogeneous multicore system for scientific programming. The core is multithread for streaming processing. And the communication network InfiniBand is adopted for scalability. We design a binary search algorithm to address mapping to unify all processor addresses. Within the limits permitted by the Graph500 test bench after 1D parallel hybrid BFS algorithm testing, our 8-core and 8-thread-per-core system achieved superior performance and efficiency compared with the prior work under the same degree of parallelism. Our system is efficient not as a special acceleration unit but as a processor platform that deals with graph searching applications.

Effect of adipocyte-secreted factors on EpCAM+/CD133+ hepatic stem cell population

Recent epidemiological studies have associated obesity with a variety of cancer types including HCC. However, the tumor initiating role of obesity in hepatocarcinogenesis is still unknown. The objective of this paper is to investigate the effect of adipocyte-secreted factors on EpCAM+/CD133+ cancer stem cells and to identify which factors play a role in modulating hepatic cancer stem cell behavior. Our results demonstrated that adipocyte-secreted factors affect motility and drug resistance of EpCAM+/CD133+ cells. When incubated with adipocyte conditioned media, EpCAM+/CD133+ cells exhibited augmented motility and reduced sorafenib-induced apoptosis. Using array-based system, we identified secretion of several cytokines such as IL6, IL8 and MCP1 by cultured adipocytes and activation of c-Met, STAT3 and ERK1/2 signaling pathways in EpCAM+/CD133+ cells incubated with adipocyte conditioned media. Treating EpCAM+/CD133+ cancer stem cells with IL6 receptor blocking antibody or c-Met inhibitor SU11274 both reduced the increase in motility; however SU11274 had greater effect on relieving protection from sorafenib-induced apoptosis. These results indicate that adipocyte-secreted factors might regulate cancer stem cell behavior through several signaling molecules including c-Met, STAT3 and ERK1/2 and inhibition of these signaling pathways offer novel strategies in targeting the effect of adipose-derived cytokines in cancer.

Ex vivo and in vitro production of pro-inflammatory cytokines in Blau syndrome

The objective was to study both ex vivo and in vitro secretion of pro-inflammatory cytokines in patients affected by Blau syndrome (BS) and carrying p.E383K mutation in the CARD15/NOD2 gene associated with the disease. For ex vivo studies, peripheral blood mononuclear cells (PBMCs), serum from three patients and healthy controls have been collected. PBMCs have been cultured in the presence or absence of inflammatory enhancers, such as lipopolysaccharide (LPS) and muramyl dipeptide (MDP). The levels of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α and interferon (IFN)-γ were assayed by either immunoassay or array-based system. For in vitro studies, different constructs were created cloning human wild-type and p.E383K-mutated NOD2 cDNA into the expression vector pCMV-Tag2c. HEK293 cell lines were stably transfected, cultured with or without MDP and IL-8 level was assayed in their surnatants. Statistical analysis in both studies was performed using non-parametric tests. Both ex vivo and in vitro studies have not identified a significant increase in secretion of the analyzed proinflammatory cytokines. p.E383K-mutated NOD2 transfected cells express low level of IL-8. The ex vivo basal level results from both serum and PBMCs surnatants present similar levels of IL-1β, IL-6, TNF-α and IFN-γ in patients and controls. The presence of the stimulant agents (LPS and MDP), either individual or paired, does not lead to significant increases in all cytokines concentrations in patients compared to controls. Taken together, the ex vivo and in vitro data suggest that there is not a primary mediation of IL-1β and other pro-inflammatory cytokines in BS patients carrying p.E383K.

Minitaur, an Event-Driven FPGA-Based Spiking Network Accelerator

Current neural networks are accumulating accolades for their performance on a variety of real-world computational tasks including recognition, classification, regression, and prediction, yet there are few scalable architectures that have emerged to address the challenges posed by their computation. This paper introduces Minitaur, an event-driven neural network accelerator, which is designed for low power and high performance. As an field-programmable gate array-based system, it can be integrated into existing robotics or it can offload computationally expensive neural network tasks from the CPU. The version presented here implements a spiking deep network which achieves 19 million postsynaptic currents per second on 1.5 W of power and supports up to 65 K neurons per board. The system records 92% accuracy on the MNIST handwritten digit classification and 71% accuracy on the 20 newsgroups classification data set. Due to its event-driven nature, it allows for trading off between accuracy and latency.

Changes in serum immunomolecules during antibiotic therapy forMycobacterium aviumcomplex lung disease

Little information is available regarding changes in immune status for patients with Mycobacterium avium complex (MAC) lung disease during antibiotic therapy. Serum immunomolecules from 42 patients with MAC lung disease were assayed comparatively using an array-based system according to (i) patients with MAC lung disease at the time of diagnosis versus healthy controls and (ii) alterations after 12 months of antibiotic therapy in the MAC lung disease group. In addition, cytokine analyses were performed to determine whether cytokine responses were associated specifically with the disease phenotype, treatment outcome and aetiological agent. Notably, the serum concentrations of type 1 cytokine-associated molecules, such as CD40L, interferon (IFN)-γ, interleukin (IL)-8 and IL-23, were decreased significantly in patients at the time of diagnosis, suggesting that these molecules may serve as indicators of host susceptibility to MAC disease. Although the overall serum level of T helper type 1 (Th1)-related molecules, such as CD40L and IFN-γ, was restored after treatment, Th17-related cytokines, such as IL-17 and IL-23, were down-regulated significantly at 12 months post-treatment compared to pretreatment. Furthermore, these cytokine patterns differed among patient subgroups. Decreased serum concentrations of IL-17 and/or IL-23 were associated with failure of sputum conversion, the fibrocavitary disease phenotype and M. intracellulare lung disease. Thus, the reciprocal balance between Th1 and Th17 immunity during antibiotic therapy for MAC lung disease is critical for dictating the treatment response. In conclusion, a low level of Th1-related immunomolecules may perpetuate MAC lung disease, and the serum concentrations of Th17-related cytokines can reflect the treatment outcome, disease phenotype and aetiological agent.

Sensor Non Uniformity Correction Algorithms and its Real Time Implementation for Infrared Focal Plane Array-based Thermal Imaging System

The advancement in infrared (IR) detector technologies from 1st to 3rd generation and beyond has resulted in the improvement of infrared imaging systems due to availability of IR detectors with large number of pixels, smaller pitch, higher sensitivity and large F-number. However, it also results in several problems and most serious of them is sensor non-uniformities, which are mainly attributed to the difference in the photo-response of each detector in the infrared focal plane array. These spatial and temporal non-uniformities result in a slowly varying pattern on the image usually called as fixed pattern noise and results in the degradation the temperature resolving capabilities of thermal imaging system considerably. This paper describes two types of non uniformity correction methodologies. First type of algorithms deals with correction of sensor non-uniformities based upon the calibration method. Second type of algorithm deals with correction of sensor non uniformities using scene information present in the acquired images. The proposed algorithms correct both additive and multiplicative non uniformities. These algorithms are evaluated using the simulated & actual infrared data and results of implementations are presented. Furthermore, proposed algorithms are implemented in field programmable gate array based embedded hardware. Defence Science Journal, 2013, 63(6), pp. 589-598 , DOI:http://dx.doi.org/10.14429/dsj. 63.5768

Comprehensive Mitochondrial Haplogroup Analysis System Based on Suspension-Array Technology Using DNA from Formalin-Fixed Paraffin-Embedded Autopsy Tissues (P07.214)

Objective: To establish a suspension array-based analysis system for determining mitochondrial haplogroups, using DNA purified from formalin-fixed paraffin-embedded (FFPE) autopsy tissues. Background Because the evolutionary rate of mitochondrial DNA (mtDNA) is much higher than that of nuclear DNA, and because mtDNA is highly polymorphic, mitochondrial single nucleotide polymorphisms (mtSNPs) are expected to contribute more extensively to the functional differences among individuals than those SNPs in the nuclear DNA. Design/Methods: We carefully purified total DNA from FFPE autopsy tissues by using ethanol precipitation. By using our system, we could estimate 7 major mitochondrial haplogroups for Japanese (A, D, D4, D5, F, G1, and G2) containing 17 subhaplogroups (B4b, B4c, B5, D4a, D4b1b, D4b2a, D4b2b, D4d1b, D4e1, D4e2, D4g, D4h, M7a, M7b, M10, N9a, and N9b) belonging to 2 super haplogroups (M and N), based on information obtained from the comprehensive analysis of mtSNPs in the coding region of mtDNA. We first tested approximately 100 DNA samples from blood and FFPE tissues of autopsy subjects whose haplogroups had been identified by DNA analysis of frozen-kidney tissues. To examine more fully the utility of the system, we analyzed 5,161 DNA samples from FFPE tissues. Results: We could analyze 4,485 (87%) of them successfully. However, we could not analyze the remainder (13%) because of an insufficient PCR amplification due to severe DNA fragmentation. We had previously revealed the haplogroup frequencies of 1,500 frozen-kidney DNA samples. In comparison, the haplogroup D4a was overestimated, but the haplogroups M7a, D4b1b and N9b were underestimated, by the present system we developed. Conclusions: We have established a method to purify DNA from FFPE tissues and developed a suspension array-based analytic system to estimate major haplogroups of Japanese individuals. We believe that our system for the classification of mitochondrial haplogroups will be very helpful not only for pathogenetical studies, but also for epidemiological cohort studies. Supported by: In part by grants from the program Grants-in-Aid for Scientific Research (C) [18590317, and 21590411]; by Grant 20B-13 from the program Research Grants for Nervous and Mental Disorders of the Ministry of Health, Labour, and Welfare; and by grants for scientific research from the Takeda Science Foundation, and Sankyo Foundation of Life Science. Disclosure: Dr. Nishigaki has nothing to disclose. Dr. Hosoya has nothing to disclose. Dr. Naka-Mieno has nothing to disclose. Dr. Arai has nothing to disclose. Dr. Sawabe has nothing to disclose. Dr. Tanaka has nothing to disclose.

Application of immunosignatures to the assessment of Alzheimer's disease

Accurate assessment of Alzheimer's disease (AD), both presymptomatically and at different disease stages, will become increasingly important with the expanding elderly population. There are a number of indications that the immune system is engaged in AD. Here we explore the ability of an antibody-profiling technology to characterize AD and screen for peptides that may be used for a simple diagnostic test. We developed an array-based system to profile the antibody repertoire of transgenic mice with cerebral amyloidosis (TG) and elderly individuals with or without AD. The array consists of 10,000 random sequence peptides (20-mers) capable of detecting antibody binding patterns, allowing the identification of peptides that mimic epitopes targeted by a donor's serum. TG mice exhibited a distinct immunoprofile compared to nontransgenic littermates. Further, we show that dementia patients, including autopsy-confirmed AD subjects, have distinguishable profiles compared to age-matched nondemented people. Using antibodies to different forms of Aβ peptide and blocking protocols, we demonstrate that most of this signature is not due to the subject's antibodies raised against Aβ. We propose that "immunosignaturing" technology may have potential as a diagnostic tool in AD.

Researching of airflow circulation system in wood drying kiln based on array fans

This paper investigates the airflow circulation system based on array fans for wood drying kiln process incorporating the simulation of airflow patterns, velocity and pressure distributions. A description of the array-based airflow circulation system is presented, furthermore, by setting the mesh size, grid unit and boundary conditions appropriately with fluid tools and using the renormalisation group (RNG) k-e turbulence model theory, simulation experiments are established. The results are evaluated to demonstrate that the designed system can improve working efficiency and wood drying rate; in addition, it can also avoid the defects and energy wasting. The system developed in this study may be applied in industrial wood-drying kilns, with a clear potential for improved quality and increased speed of drying.

Determination of Microcystins in River Waters Using Microsensor Arrays on Disk

The development of simple, accurate, and rapid multisample analytical methodologies to find out critical targets in waters is highly demanded. Optical microsensor arrays to determine microcystins in river waters are developed on the polycarbonate side of compact discs. The working principle of the sensors relied on an indirect competitive microimmunoassay, where free microcystin LR (MC-LR) competes with immobilized conjugate for specific monoclonal antibody. The results of the immunoreaction are detected with a DVD drive, showing the readouts in minutes. The method reached a sensitivity (IC(50)) for MC-LR of 1.04 μg/L and a linear response in the range 0.12-2.00 μg/L, allowing its determination below the upper limit proposed by the World Health Organization in drinking water. The developed analytical approach shows simplicity, good sensitivity, high throughput capability, and rapidity (37 min) in field use. The optimized assay showed also high congener reactivity to MC-LY (144%), MC-LA (125%), MC-LF (119%), MC-LW (102%), MC-YR (83%), and nodularin (94%). Furthermore, the suitability of the disk biosensor to quantify MC-LR was successfully evaluated analyzing river water samples, obtaining excellent recoveries (78-113%). Precoated discs are stable for at least seven weeks without loosing their analytical performances. Also, the portability of the analytical system permits on-site analysis and quantification, saving time and other resources. To our knowledge, this is the only work where a portable, easy-to-use, array based system has been developed for on-site microcystin quantification and applied to simultaneously analyze 42 samples plus the calibration curve, reaching microgram per liter sensitivity.

Monitoring ion-channel function in real time through quantum decoherence

In drug discovery, there is a clear and urgent need for detection of cell-membrane ion-channel operation with wide-field capability. Existing techniques are generally invasive or require specialized nanostructures. We show that quantum nanotechnology could provide a solution. The nitrogen-vacancy (NV) center in nanodiamond is of great interest as a single-atom quantum probe for nanoscale processes. However, until now nothing was known about the quantum behavior of a NV probe in a complex biological environment. We explore the quantum dynamics of a NV probe in proximity to the ion channel, lipid bilayer, and surrounding aqueous environment. Our theoretical results indicate that real-time detection of ion-channel operation at millisecond resolution is possible by directly monitoring the quantum decoherence of the NV probe. With the potential to scan and scale up to an array-based system, this conclusion may have wide-ranging implications for nanoscale biology and drug discovery.

Abstract 3985: New quantification tools for perfusion and VEGFR2 Expression in tumors

Abstract Microbubble contrast agents are used to enhance the visualization of the microcirculation in human and mouse tumors. Specifically, contrast agents allow for the relative quantification of tissue perfusion and vascular volume. The in vivo expression of endothelial cell surface markers can also be studied using targeted microbubbles. In this study a nonlinear contrast agent imaging technique, employing amplitude modulation on a linear array-based micro-ultrasound system was used to visualize and quantify time to peak enhancement (TP) and vascular volume (VV) in subcutaneous tumors, as well as to assess expression levels of VEGFR2. A Vevo 2100 high resolution ultrasound imaging system (VisualSonics Inc, Toronto, Canada) was used and all images were acquired with the MS-250 (center operating frequency of 20MHz, axial resolution 75um) probe. Tumor flow was assessed using MicroMarker contrast agents. A bolus delivery was employed to generate time-intensity curves of contrast wash-in; prototype analytical software was used to perform curve fit analysis and to generate parametric images visually depicting VV and TP as an overlay on the anatomical images. Additionally, Target-Ready MicroMarker contrast agents were conjugated to VEGFR2 antibodies to assess the expression level of this endothelial cell surface receptor. Again, prototype analytical software was used to quantify the relative expression of this target and to generate parametric images of its expression pattern within the tumor. All images were acquired from athymic nude mice implanted with hepatocellular carcinoma cells (Hep3B-Luc-C4) subdermally in the hind limb 4 to 5 weeks before imaging. Results showed heterogeneity in TP and VV in all tumors. TP ranged from 3.5 seconds in well perfused regions to 12 seconds in poorly perfused tumor regions. The graphical appearance of the associated parametric images readily revealed these differences. Assessment of VEGFR2 expression completed in 2D and 3D showed 2-3 times enhancement in VEGFR2 binding over that observed with the isotype control antibody. These results are consistent with previous methods using linear contrast processing. Overall this study shows the utility of nonlinear processing of contrast signals in assessment of various flow related parameters of the tumor microcirculation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3985.

Novel low-power ultrasound digital preprocessing architecture for wireless display

A complete hardware-based ultrasound preprocessing unit (PPU) is presented as an alternative to available power-hungry devices. Intended to expand the ultrasonic applications, the proposed unit allows replacement of the cable of the ultrasonic probe by a wireless link to transfer data from the probe to a remote monitor. The digital back-end architecture of this PPU is fully pipelined, which permits sampling of ultrasonic signals at a frequency equal to the field-programmable gate array-based system clock, up to 100 MHz. Experimental results show that the proposed processing unit has an excellent performance, an equivalent 53.15 Dhrystone 2.1 MIPS/ MHz (DMIPS/MHz), compared with other software-based architectures that allow a maximum of 1.6 DMIPS/MHz. In addition, an adaptive subsampling method is proposed to operate the pixel compressor, which allows real-time image zooming and, by removing high-frequency noise, the lateral and axial resolutions are enhanced by 25% and 33%, respectively. Realtime images, acquired from a reference phantom, validated the feasibility of the proposed architecture. For a display rate of 15 frames per second, and a 5-MHz single-element piezoelectric transducer, the proposed digital PPU requires a dynamic power of only 242 mW, which represents around 20% of the best-available software-based system. Furthermore, composed by the ultrasound processor and the image interpolation unit, the digital processing core of the PPU presents good power-performance ratios of 26 DMIPS/mW and 43.9 DMIPS/mW at a 20-MHz and 100-MHz sample frequency, respectively.

Light-Weight SMT-based Model Checking

Recently, the notion of an array-based system has been introduced as an abstraction of infinite state systems (such as mutual exclusion protocols or sorting programs) which allows for model checking of invariant (safety) and recurrence (liveness) properties by Satisfiability Modulo Theories (SMT) techniques. Unfortunately, the use of quantified first-order formulae to describe sets of states makes fix-point checking extremely expensive. In this paper, we show how invariant properties for a sub-class of array-based systems can be model-checked by a backward reachability algorithm where the length of quantifier prefixes is efficiently controlled by suitable heuristics. We also present various refinements of the reachability algorithm that allows it to be easily implemented in a client-server architecture, where a ''light-weight'' algorithm is the client generating proof obligations for safety and fix-point checks and an SMT solver plays the role of the server discharging the proof obligations. We also report on some encouraging preliminary experiments with a prototype implementation of our approach.

Detection and differentiation of normal, cancerous, and metastatic cells using nanoparticle-polymer sensor arrays

Rapid and effective differentiation between normal and cancer cells is an important challenge for the diagnosis and treatment of tumors. Here, we describe an array-based system for identification of normal and cancer cells based on a "chemical nose/tongue" approach that exploits subtle changes in the physicochemical nature of different cell surfaces. Their differential interactions with functionalized nanoparticles are transduced through displacement of a multivalent polymer fluorophore that is quenched when bound to the particle and fluorescent after release. Using this sensing strategy we can rapidly (minutes/seconds) and effectively distinguish (i) different cell types; (ii) normal, cancerous and metastatic human breast cells; and (iii) isogenic normal, cancerous and metastatic murine epithelial cell lines.