Customized Design of Magnetic Beads for Dynamic Magnetoresistive Cytometry

Vila, Ana; Martins, Verónica C.; Chícharo, Alexandre; Rodríguez‐Abreu, Carlos; Fernandes, Ana C.; Cardoso, Fabbryccio A. C. M.; Cardoso, S.; Rivas, José; Freitas, P. P.

doi:10.1109/tmag.2014.2324411

Cited by 12 publications

(6 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In general, after the functionalisation process around 68–80% of the surface of polymer beads was covered by protein (determined by indirect quantification in supernatant using fluorescence or colorimetric methods) [ 28 ].…”

Section: Resultsmentioning

confidence: 99%

“…First, oleic acid capped magnetite nanoparticles (OMN) were prepared by precipitation from two iron salts (FeCl 3 and FeCl 2 ) in the presence of ammonium hydroxide followed by the addition of oleic acid [ 27 ]. The OMN average size is 10 nm with a polydispersity index of 0.2 as determined by Transmission Electron Microscopy (TEM; TITAN® 200 Kv ChemiS TEM) and Dynamic Light Scattering (DLS) cumulant analysis (Horiba Scientific SZ-100) [ 28 ].…”

Section: Methodsmentioning

confidence: 99%

See 1 more Smart Citation

EGFR-Based Immunoisolation as a Recovery Target for Low-EpCAM CTC Subpopulation

et al. 2016

Self Cite

View full text Add to dashboard Cite

Circulating tumour cells (CTCs) play a key role in the metastasis process, as they are responsible for micrometastasis and are a valuable tool for monitoring patients in real-time. Moreover, efforts to develop new strategies for CTCs isolation and characterisation, and the translation of CTCs into clinical practice needs to overcome the limitation associated with the sole use of Epithelial Cell Adhesion Molecule (EpCAM) expression to purify this tumour cell subpopulation. CTCs are rare events in the blood of patients and are believed to represent the epithelial population from a primary tumour of epithelial origin, thus EpCAM immunoisolation is considered an appropriate strategy. The controversy stems from the impact that the more aggressive mesenchymal tumour phenotypes might have on the whole CTC population. In this work, we first characterised a panel of cell lines representative of tumour heterogeneity, confirming the existence of tumour cell subpopulations with restricted epithelial features and supporting the limitations of EpCAM-based technologies. We next developed customised polystyrene magnetic beads coated with antibodies to efficiently isolate the phenotypically different subpopulations of CTCs from the peripheral blood mononuclear cells (PBMCs) of patients with metastatic cancer. Besides EpCAM, we propose Epidermal Growth Factor Receptor (EGFR) as an additional isolation marker for efficient CTCs detection.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

EGFR-Based Immunoisolation as a Recovery Target for Low-EpCAM CTC Subpopulation

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…Magnetic nanoparticles can be collected by the application of a magnetic field; this property can be exploited to isolate bacteria by their specific binding to nanoparticles. Therefore, IMBs were prepared by modifying their surfaces with streptavidin while modifying E. coli-specific antibodies with biotin and then mixing the two together [18], [19]. Thus, the material could be used to specifically isolate or enrich E. coli using a magnetic field (Fig.…”

Section: Detection Principlementioning

confidence: 99%

A Rapid Detection System Design for Escherichia Coli in Food Based on a Nanoprobe and Graphite Electrode Coupled With ATP Bioluminescence Technology

Zhang

Wang

2019

IEEE Access

View full text Add to dashboard Cite

Food safety concerns owing to bacterial contamination have drawn significant attention; thus, the development of techniques for rapid and accurate detection of pathogens is an active research area. The development of a biological detection methodology based on techniques such as nanoprobe, graphene transparent electrode (GTE), or adenosine triphosphate (ATP) luminescence is described in this paper. Two system parts were designed; one can pump reagents precisely controlled by a microprogrammed control unit (MCU), whereas the other can rapidly process signals from a photomultiplier tube (PMT) by the hard module. Thus, the system works automatically and detects bacteria in food rapidly. The system not only uses the probe to capture and enrich Escherichia coli via an antibody-antigen reaction but also enriches ATP using an electric field generated by the GTE to further improve the accuracy of the system. Compared with the other conventional approaches, this system can produce a linear correlation coefficient of up to 0.972 and meet the design demand. Moreover, detection can be completed within 20 min. The detectable bacterial concentration range is 10 2-10 6 CFU/mL. Additionally, a series of curves obtained by measurements of different polluted food products such as drinks, meat, and grains show that the system has a satisfactory performance. It meets the requirements of a rapid, on-site detection system.

show abstract

“…Spherical magnetic beads already play an important role in microfluidics; they can be made to link to target species and can be used for manipulation and/or detection in lab-on-achip systems [8][9][10] and protein and biomolecular purification and mixing. They are also used for generating and measuring forces at the micrometre scale in biophysical studies, [11][12][13] in torquegenerating assays, [14] cellular mechanotransduction and microrheology, in magnetic twisting cytometry, [15,16] in cellular, protein and nucleic acid manipulation in separation assays, [17] in immunoassays, [18] in magnetic flow cytometry, [19] in magnetic separation in lab-on-a-chip microfluidic systems, [20] in directed hyperthermia applications [11,21] and targeted drug delivery. [22] Most applications use commercial spherical MPC microparticles consisting of a polymeric matrix that confines magnetic spherical superparamagnetic Fe 3 O 4 nanoparticles (NPs).…”

Section: Introductionmentioning

confidence: 99%

Polymeric microellipsoids with programmed magnetic anisotropy for controlled rotation using low (≈10 mT) magnetic fields

Bonilla-Brunner

Llorente-Garcia

Jang

et al. 2020

Applied Materials Today

View full text Add to dashboard Cite

Polymeric magnetic spherical microparticles are employed as sensors/actuators in lab-on-a-chip applications, small-scale robotics and biomedical/biophysical assays. Achieving controlled stable motion of the microparticles in a fluid environment using low intensity magnetic fields is necessary to achieve much of their technological potential; this requires that the microparticle is magnetically anisotropic, which is difficult to achieve in spheres. Here we have developed a simple method to synthesise anisotropic ellipsoidal microparticles (average eccentricity 0.60 ± 0.14) by applying a magnetic field during synthesis, using a nanocomposite of polycaprolactone (PCL) with Fe 3 O 4 nanowires. The "microellipsoids" are thoroughly characterised using optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). Their suitability for magnetically controlled motion is demonstrated by analysing their rotation in low magnetic fields (0.1, 1, 5, 10 and 20 mT) at varying rotational frequencies (1Hz and 5Hz). The microellipsoids are able to follow smoothly and continuously the magnetic field, while commercial spherical particles fail to continuously follow the magnetic field, and oscillate backwards and forwards resulting in much lower average angular speeds. Furthermore, only 23% of commercial particles analysed rotated at 1 Hz and 26% at 5 Hz, whereas 77% of our ellipsoidal particles rotated at 1 Hz, and 74% did at 5 Hz.

show abstract

Customized Design of Magnetic Beads for Dynamic Magnetoresistive Cytometry

Cited by 12 publications

References 9 publications

EGFR-Based Immunoisolation as a Recovery Target for Low-EpCAM CTC Subpopulation

EGFR-Based Immunoisolation as a Recovery Target for Low-EpCAM CTC Subpopulation

A Rapid Detection System Design for Escherichia Coli in Food Based on a Nanoprobe and Graphite Electrode Coupled With ATP Bioluminescence Technology

Polymeric microellipsoids with programmed magnetic anisotropy for controlled rotation using low (≈10 mT) magnetic fields

Contact Info

Product

Resources

About