scholarly journals Immobilization of Protein A on Monodisperse Magnetic Nanoparticles for Biomedical Applications

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Bui Trung Thanh ◽  
Nguyen Van Sau ◽  
Heongkyu Ju ◽  
Mohammed J. K. Bashir ◽  
Hieng Kiat Jun ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Magnetic Nanoparticles ◽  
Biomedical Applications ◽  
Point Of Care ◽  
High Surface ◽  
Protein A ◽  
Volume Ratio ◽  
Controlled Drug Release ◽  
Disease Diagnosis

We presented synthesis and physical characterization of iron oxide magnetic nanoparticles (Fe3O4) for biomedical applications in the size range of 10-30 nm. Magnetic nanoparticles were synthesized by the coprecipitation method, and the particles’ size was controlled by two different injection methods of sodium hydroxide (NaOH). The synthesized magnetic nanoparticles were then modified by using series of linkers including tetraethyl orthosilicate (TEOS), 3-aminopropyltriethoxysilane (APTES), and glutaraldehyde (GA) to generate the structure of Fe3O4/SiO2/NH2/CHO, which can be used for immobilization of protein A. Additionally, we used transmission electron microscopy (TEM), X-ray powder diffraction (XRD), vibrating-sample magnetometry (VSM), and Fourier-transform infrared spectroscopy (FTIR), for characterization of properties and structure of the nanoparticles. An immobilization of protein A on magnetic nanoparticles was studied with a UV-Vis spectrum (UV-Vis) and fluorescence electron microscopy and Bradford method. Results showed that an XRD spectrum with a peak at (311) corresponded to the standard peak of magnetic nanoparticles. In addition, the magnetic nanoparticles with d≥30 nm have higher saturation magnetizations in comparison with the smaller ones with d≤10 nm. However, the smaller magnetic nanoparticles offered higher efficiency for binding of protein A, due to the high surface/volume ratio. These particles with functional groups on their surface are promising candidates for biomedical applications, e.g., drug delivery, controlled drug release, or disease diagnosis in point-of-care test.

scholarly journals A Review on Biosensors and Recent Development of Nanostructured Materials-Enabled Biosensors

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1109
Author(s):  
Varnakavi. Naresh ◽  
Nohyun Lee
Keyword(s):  
High Surface ◽  
Three Dimensional ◽  
Biological Response ◽  
Volume Ratio ◽  
Recent Decade ◽  
Disease Diagnosis ◽  
Electrical Signal ◽  
Detection Sensitivity ◽  
Wide Range ◽  
Color Tunability

A biosensor is an integrated receptor-transducer device, which can convert a biological response into an electrical signal. The design and development of biosensors have taken a center stage for researchers or scientists in the recent decade owing to the wide range of biosensor applications, such as health care and disease diagnosis, environmental monitoring, water and food quality monitoring, and drug delivery. The main challenges involved in the biosensor progress are (i) the efficient capturing of biorecognition signals and the transformation of these signals into electrochemical, electrical, optical, gravimetric, or acoustic signals (transduction process), (ii) enhancing transducer performance i.e., increasing sensitivity, shorter response time, reproducibility, and low detection limits even to detect individual molecules, and (iii) miniaturization of the biosensing devices using micro-and nano-fabrication technologies. Those challenges can be met through the integration of sensing technology with nanomaterials, which range from zero- to three-dimensional, possessing a high surface-to-volume ratio, good conductivities, shock-bearing abilities, and color tunability. Nanomaterials (NMs) employed in the fabrication and nanobiosensors include nanoparticles (NPs) (high stability and high carrier capacity), nanowires (NWs) and nanorods (NRs) (capable of high detection sensitivity), carbon nanotubes (CNTs) (large surface area, high electrical and thermal conductivity), and quantum dots (QDs) (color tunability). Furthermore, these nanomaterials can themselves act as transduction elements. This review summarizes the evolution of biosensors, the types of biosensors based on their receptors, transducers, and modern approaches employed in biosensors using nanomaterials such as NPs (e.g., noble metal NPs and metal oxide NPs), NWs, NRs, CNTs, QDs, and dendrimers and their recent advancement in biosensing technology with the expansion of nanotechnology.

scholarly journals Water uptake of various electrospun nonwovens

2020 ◽  
Vol 6 (3) ◽  
pp. 155-158
Author(s):  
Katharina Wulf ◽  
Volkmar Senz ◽  
Thomas Eickner ◽  
Sabine Illner
Keyword(s):  
Contact Angle ◽  
Surface Modification ◽  
Water Absorption ◽  
Water Uptake ◽  
Biomedical Applications ◽  
High Surface ◽  
Volume Ratio ◽  
Polymer Composition ◽  
Water Wetting ◽  
Morphology Changes

AbstractIn recent years, nanofiber based materials have emerged as especially interesting for several biomedical applications, regarding their high surface to volume ratio. Due to the superficial nano- and microstructuring and the different wettability compared to nonstructured surfaces, the water absorption is an important parameter with respect to the degradation stability, thermomechanic properties and drug release properties, depending on the type of polymer [1]. In this investigation, the water absorption of different non- and plasma modified biostable nanofiber nonwovens based on polyurethane, polyester and polyamide were analysed and compared. Also, the water absorption by specified water wetting, the contact angle and morphology changes were examined. The results show that the water uptake is highly dependent on the surface modification and the polymer composition itself and can therefore be partially changed.

Recent Advances in the Development of Magnetic Nanoparticles for Biomedical Applications

2021 ◽  
Vol 21 (5) ◽  
pp. 2705-2741
Author(s):  
Maria Monteserín ◽  
Silvia Larumbe ◽  
Alejandro V. Martínez ◽  
Saioa Burgui ◽  
L. Francisco Martín
Keyword(s):  
Magnetic Nanoparticles ◽  
Physicochemical Properties ◽  
Biomedical Applications ◽  
High Surface ◽  
High Surface Area ◽  
Synthetic Methods ◽  
Magnetic Drug Targeting ◽  
Surface Area Ratio ◽  
Biomedical Field

The unique properties of magnetic nanoparticles have led them to be considered materials with significant potential in the biomedical field. Nanometric size, high surface-area ratio, ability to function at molecular level, exceptional magnetic and physicochemical properties, and more importantly, the relatively easy tailoring of all these properties to the specific requirements of the different biomedical applications, are some of the key factors of their success. In this paper, we will provide an overview of the state of the art of different aspects of magnetic nanoparticles, specially focusing on their use in biomedicine. We will explore their magnetic properties, synthetic methods and surface modifications, as well as their most significative physicochemical properties and their impact on the in vivo behaviour of these particles. Furthermore, we will provide a background on different applications of magnetic nanoparticles in biomedicine, such as magnetic drug targeting, magnetic hyperthermia, imaging contrast agents or theranostics. Besides, current limitations and challenges of these materials, as well as their future prospects in the biomedical field will be discussed.

scholarly journals Label-Free Optical Biosensing Using Low-Cost Electrospun Polymeric Nanofibers

Chemosensors ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 119
Author(s):  
Paula Martínez-Pérez ◽  
Salvador Ponce-Alcántara ◽  
Nieves Murillo ◽  
Ana Pérez-Márquez ◽  
Jon Maudes ◽  
...  
Keyword(s):  
Real Time ◽  
Large Scale ◽  
High Surface ◽  
Protein A ◽  
Volume Ratio ◽  
Polyamide 6 ◽  
Optical Biosensor ◽  
Label Free ◽  
Electrospinning Technique ◽  
Optical Biosensing

Polymeric nanofiber matrices are promising structures to develop biosensing devices due to their easy and affordable large-scale fabrication and their high surface-to-volume ratio. In this work, the suitability of a polyamide 6 nanofiber matrix for the development of a label-free and real-time Fabry–Pérot cavity-based optical biosensor was studied. For such aim, in-flow biofunctionalization of nanofibers with antibodies, bound through a protein A/G layer, and specific biodetection of 10 µg/mL bovine serum albumin (BSA) were carried out. Both processes were successfully monitored via reflectivity measurements in real-time without labels and their reproducibility was demonstrated when different polymeric nanofiber matrices from the same electrospinning batch were employed as transducers. These results demonstrate not only the suitability of correctly biofunctionalized polyamide 6 nanofiber matrices to be employed for real-time and label-free specific biodetection purposes, but also the potential of electrospinning technique to create affordable and easy-to-fabricate at large scale optical transducers with a reproducible performance.

Magnetic Nanoparticles: Current Trends and Future Aspects in Diagnostics and Nanomedicine

2019 ◽  
Vol 20 (6) ◽  
pp. 457-472 ◽  
Author(s):  
Naga Veera Srikanth Vallabani ◽  
Sanjay Singh ◽  
Ajay Singh Karakoti
Keyword(s):  
Magnetic Nanoparticles ◽  
Biomedical Applications ◽  
Antimicrobial Agents ◽  
Superparamagnetic Iron Oxide ◽  
Disease Diagnosis ◽  
Imaging Modalities ◽  
Clinical Settings ◽  
Current Trends ◽  
Recent Developments ◽  
Near Future

Background: Biomedical applications of Magnetic Nanoparticles (MNPs) are creating a major impact on disease diagnosis and nanomedicine or a combined platform called theranostics. A significant progress has been made to engineer novel and hybrid MNPs for their multifunctional modalities such as imaging, biosensors, chemotherapeutic or photothermal and antimicrobial agents. MNPs are successfully applied in biomedical applications due to their unique and tunable properties such as superparamagnetism, stability, and biocompatibility. Approval of ferumoxytol (feraheme) for MRI and the fact that several Superparamagnetic Iron Oxide Nanoparticles (SPIONs) are currently undergoing clinical trials have paved a path for future MNPs formulations. Intensive research is being carried out in designing and developing novel nanohybrids for multiple applications in nanomedicine. Objective: The objective of the present review is to summarize recent developments of MNPs in imaging modalities like MRI, CT, PET and PA, biosensors and nanomedicine including their role in targeting and drug delivery. Relevant theory and examples of the use of MNPs in these applications have been cited and discussed to create a thorough understanding of the developments in this field. Conclusion: MNPs have found widespread use as contrast agents in imaging modalities, as tools for bio-sensing, and as therapeutic and theranostics agents. Multiple formulations of MNPs are in clinical testing and may be accepted in clinical settings in near future.

Fabrication Process Development and Characterization of Polymethylhydrosiloxane (PMHS) for Surface-Modified Microfluidic Chips

2007 ◽  
Author(s):  
Mukund Vijay ◽  
Ehson Ghandehari ◽  
Michel Goedert ◽  
Sang-Joon J. Lee
Keyword(s):  
Laser Ablation ◽  
Soft Lithography ◽  
Process Development ◽  
High Surface ◽  
Volume Ratio ◽  
Fused Silica ◽  
Polymer Materials ◽  
Microfluidic Chips ◽  
Separation Processes

Microfluidic chips made of polymer materials such as polydimethylsiloxane (PDMS), polyimide, and cyclic olefin co-polymer have cost and manufacturing advantages over materials such as fused silica and borosilicate glass. While these materials have been extensively investigated, polymethylhydrosiloxane (PMHS) is an alternative that has a unique combination of properties in terms of UV transparency and potential for chemical surface modification. The present study investigates process development and characterization of PMHS as a new candidate material for microfluidic chip applications, in particular separation processes that would benefit from the ability to custom-engineer its surface conditions. This paper compares different approaches for fabricating microchannel features as well as options for enhancing the surface area of the channel walls. The fabrication methods include replication by casting over patterned molds, soft lithography casting, and material removal by laser ablation. Casting into solid form is achieved in 48-hours at 110 °C. Laser ablation is studied with energy dose varying from 2 mJ to 160 mJ per millimeter scanned, with channels approximately 100 microns wide occurring at 0.2 mJ/mm. Mechanical characterization is applied to quantify the hardness of cast PMHS, because fine-resolution features are limited by mold removal. PMHS samples have been measured to have a Shore A hardness of 46.2, similar to PDMS that is well-established in polymer microfluidic devices. Surface enhancement techniques including laser and plasma treatment are investigated for the prospective benefit of separation processes that require high surface-to-volume ratio. Spectrophotometry shows that PMHS exhibits transmittance even below 250 nm, which is favorable for sample analysis by UV absorption methods.

scholarly journals Characterization of carbon-coated magnetic nanoparticles using clinical blood coagulation assays: effect of PEG-functionalization and comparison to silica nanoparticles

2014 ◽  
Vol 2 (24) ◽  
pp. 3753-3758 ◽  
Author(s):  
Lukas Bircher ◽  
Oliver M. Theusinger ◽  
Silvan Locher ◽  
Philipp Eugster ◽  
Birgit Roth-Z'graggen ◽  
...  
Keyword(s):  
Magnetic Nanoparticles ◽  
Blood Coagulation ◽  
Human Blood ◽  
Point Of Care ◽  
Blood Samples ◽  
Coagulation Assays ◽  
Carbon Coated ◽  
Human Blood Samples ◽  
Peg Functionalization

We use point-of-care-assays to study blood coagulation in human blood samples exposed to nanomagnets.

scholarly journals Graphene-based biosensors

2018 ◽  
Vol 8 (3) ◽  
pp. 20160132 ◽  
Author(s):  
Sabine Szunerits ◽  
Rabah Boukherroub
Keyword(s):  
Biological Samples ◽  
Early Stage ◽  
Point Of Care ◽  
High Surface ◽  
Volume Ratio ◽  
Wide Range ◽  
The Status ◽  
Delays In Diagnosis ◽  
Short Time ◽  
Sensor Interfaces

Reliable data obtained from analysis of DNA, proteins, bacteria and other disease-related molecules or organisms in biological samples have become a fundamental and crucial part of human health diagnostics and therapy. The development of non-invasive tests that are rapid, sensitive, specific and simple would allow patient discomfort to be prevented, delays in diagnosis to be avoided and the status of a disease to be followed up. Bioanalysis is thus a progressive discipline for which the future holds many exciting opportunities. The use of biosensors for the early diagnosis of diseases has become widely accepted as a point-of-care diagnosis with appropriate specificity in a short time. To allow a reliable diagnosis of a disease at an early stage, highly sensitive biosensors are required as the corresponding biomarkers are generally expressed at very low concentrations. In the past 50 years, various biosensors have been researched and developed encompassing a wide range of applications. This contrasts the limited number of commercially available biosensors. When it comes to sensing of biomarkers with the required picomolar (pM) sensitivity for real-time sensing of biological samples, only a handful of sensing systems have been proposed, and these are often rather complex and costly. Lately, graphene-based materials have been considered as superior over other nanomaterials for the development of sensitive biosensors. The advantages of graphene-based sensor interfaces are numerous, including enhanced surface loading of the desired ligand due to the high surface-to-volume ratio, excellent conductivity and a small band gap that is beneficial for sensitive electrical and electrochemical read-outs, as well as tunable optical properties for optical read-outs such as fluorescence and plasmonics. In this paper, we review the advances made in recent years on graphene-based biosensors in the field of medical diagnosis.

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