共查询到20条相似文献,搜索用时 31 毫秒
1.
Scherrine A. Tria Leslie H. Jimison Adel Hama Manuelle Bongo Róisín M. Owens 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
The gastrointestinal epithelium provides a physical and biochemical barrier to the passage of ions and small molecules; however this barrier may be breached by pathogens and toxins. The effect of individual pathogens/toxins on the intestinal epithelium has been well characterized: they disrupt barrier tissue in a variety of ways, such as by targeting tight junction proteins, or other elements of the junctions between adjacent cells. A variety of methods have been used to characterize disruption in barrier tissue, such as immunofluorescence, permeability assays and electrical measurements of epithelia resistance, but these methods remain time consuming, costly and ill-suited to diagnostics or high throughput toxicology.Methods
The advent of organic electronics has created a unique opportunity to interface the worlds of electronics and biology, using devices such as the organic electrochemical transistor (OECT), whose low cost materials and potential for easy fabrication in high throughput formats represent a novel solution for assessing epithelial tissue integrity.Results
In this study, OECTs were integrated with gastro-intestinal cell monolayers to study the integrity of the gastrointestinal epithelium, providing a very sensitive way to detect minute changes in ion flow across the cell layer due to inherent amplification by the transistor.Major conclusions
We validate the OECT against traditional methods by monitoring the effect of toxic compounds on epithelial tissue. We show a systematic characterization of this novel method, alongside existing methods used to assess barrier tissue function.General significance
The toxic compounds induce a dramatic disruption of barrier tissue, and the OECT measures this disruption with increased temporal resolution and greater or equal sensitivity when compared with existing methods. This article is part of a Special Issue entitled Organic Bioelectronics — Novel Applications in Biomedicine. 相似文献2.
Background
In biosensors with a fluid analyte, the integration of a microfluidic system, which guides the analyte into the sensing area, is critical. Quicker and economical ways to build up microfluidic systems will make point of care diagnostics viable. Printing is a low-cost technology that is increasingly used in emerging organic and flexible electronics and biosensors. In this paper, we present printed fluidic systems on flexible substrates made with pressure sensitive adhesive materials.Methods
Printable pressure sensitive adhesive materials have been used for making microfluidic systems. Flexible substrates have been used, and two types of adhesive materials, one thermally dried and another UV curable, have been tested. Top sealing layer was laminated directly on top of the printed microfluidic structure. Flow tests were done with deionized water.Results
Flow tests with deionized water show that both adhesive materials are suitable for capillary flow driven fluidic devices. Flow test using water as dielectric material was also done successfully on a printed electrolyte gated organic field effect transistor with an integrated microfluidic system.General significance
Due to its ease of process and low cost, printed microfluidic system is believed to find more applications in biosensing devices. This article is part of a Special Issue entitled Organic Bioelectronics—Novel Applications in Biomedicine. 相似文献3.
Giuseppe Tarabella Anna Giulia Balducci Nicola Coppedè Simone Marasso Pasquale D'Angelo Stefano Barbieri Matteo Cocuzza Paolo Colombo Fabio Sonvico Roberto Mosca Salvatore Iannotta 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Organic electrochemical transistors (OECTs), which are becoming more and more promising devices for applications in bioelectronics and nanomedicine, are proposed here as ideally suitable for sensing and real time monitoring of liposome-based structures. This is quite relevant since, currently, the techniques used to investigate liposomal structures, their stability in different environments as well as drug loading and delivery mechanisms, operate basically off-line and/or with pre-prepared sampling.Methods
OECTs, based on the PEDOT:PSS conductive polymer, have been employed as sensors of liposome-based nanoparticles in electrolyte solutions to assess sensitivity and monitoring capabilities based on ion-to-electron amplified transduction.Results
We demonstrate that OECTs are very efficient, reliable and sensitive devices for detecting liposome-based nanoparticles on a wide dynamic range down to 10− 5 mg/ml (with a lowest detection limit, assessed in real-time monitoring, of 10− 7 mg/ml), thus matching the needs of typical drug loading/drug delivery conditions. They are hence particularly well suited for real-time monitoring of liposomes in solution. Furthermore, OECTs are shown to sense and discriminate successive injection of different liposomes, so that they could be good candidates in quality-control assays or in the pharmaceutical industry.General significance
Drug loading and delivery by liposome-based structures is a fast growing and very promising field that will strongly benefit from real-time, highly sensitive and low cost monitoring of their dynamics in different pharma and biomedical environments, with a particular reference to the pharmaceutical and production processes, where a major issue is monitoring and measuring the formation and concentration of liposomes and the relative drug load. The demonstrated ability to sense and monitor complex bio-structures, such as liposomes, paves the way for very promising developments in biosensing and nanomedicine. This article is part of a Special Issue entitled Organic Bioelectronics—Novel Applications in Biomedicine. 相似文献4.
Background
This issue of “Biochimica et Biophysica Acta — General Subjects” is dedicated to organic bioelectronics, an interdisciplinary field that has been growing at a fast pace. Bioelectronics creates tremendous promise, excitement, and hype. The application of organic electronic materials in bioelectronics offers many opportunities and is fuelled by some unique features of these materials, such as the ability to transport ions.Scope of review
This is a perspective on the history and current status of the field.Major conclusions
Organic bioelectronics currently encompasses many different applications, including neural interfaces, tissue engineering, drug delivery, and biosensors. The interdisciplinary nature of the field necessitates collaborations across traditional scientific boundaries.General significance
Organic bioelectronics is a young and exciting interdisciplinary field. This article is part of a Special Issue entitled Organic Bioelectronics — Novel Applications in Biomedicine. 相似文献5.
Akira Matsumoto Hiroko MatsumotoYasuhiro Maeda Yuji Miyahara 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Field effect transistor (FET) based signal-transduction (Bio-FET) is an emerging technique for label-free and real-time basis biosensors for a wide range of targets. Glucose has constantly been of interest due to its clinical relevance. Use of glucose oxidase (GOD) and a lectin protein Concanavalin A are two common strategies to generate glucose-dependent electrochemical events. However, these protein-based materials are intolerant of long-term usage and storage due to their inevitable denaturing.Methods
A phenylboronic acid (PBA) modified self-assembled monolayer (SAM) on a gold electrode with an optimized disassociation constant of PBA, that is, 3-fluoro-4-carbamoyl-PBA possessing its pKa of 7.1, was prepared and utilized as an extended gate electrode for Bio-FET.Results
The prepared electrode showed a glucose-dependent change in the surface potential under physiological conditions, thus providing a remarkably simple rationale for the glyco-sensitive Bio-FET. Importantly, the PBA modified electrode showed tolerance to relatively severe heat and drying treatments; conditions under which protein based materials would surely be denatured.Conclusions
A PBA modified SAM with optimized disassociation constant (pKa) can exhibit a glucose-dependent change in the surface potential under physiological conditions, providing a remarkably simple but robust method for the glyco-sensing.General significance
This protein-free, totally synthetic glyco-sensing strategy may offer cheap, robust and easily accessible platform that may be useful in developing countries. This article is part of a Special Issue entitled Organic Bioelectronics—Novel Applications in Biomedicine. 相似文献6.
Karin C. Larsson Peter KjällAgneta Richter-Dahlfors 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
A major challenge when creating interfaces for the nervous system is to translate between the signal carriers of the nervous system (ions and neurotransmitters) and those of conventional electronics (electrons).Scope of review
Organic conjugated polymers represent a unique class of materials that utilizes both electrons and ions as charge carriers. Based on these materials, we have established a series of novel communication interfaces between electronic components and biological systems. The organic electronic ion pump (OEIP) presented in this review is made of the polymer–polyelectrolyte system poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). The OEIP translates electronic signals into electrophoretic migration of ions and neurotransmitters.Major conclusions
We demonstrate how spatio-temporally controlled delivery of ions and neurotransmitters can be used to modulate intracellular Ca2 + signaling in neuronal cells in the absence of convective disturbances. The electronic control of delivery enables strict control of dynamic parameters, such as amplitude and frequency of Ca2 + responses, and can be used to generate temporal patterns mimicking naturally occurring Ca2 + oscillations. To enable further control of the ionic signals we developed the electrophoretic chemical transistor, an analog of the traditional transistor used to amplify and/or switch electronic signals. Finally, we demonstrate the use of the OEIP in a new “machine-to-brain” interface by modulating brainstem responses in vivo.General significance
This review highlights the potential of communication interfaces based on conjugated polymers in generating complex, high-resolution, signal patterns to control cell physiology. We foresee widespread applications for these devices in biomedical research and in future medical devices within multiple therapeutic areas. This article is part of a Special Issue entitled Organic Bioelectronics—Novel Applications in Biomedicine. 相似文献7.
Chu-Hua Lu Yu-Sheng Hsiao Chiung-Wen Kuo Peilin Chen 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Organic bioelectronic devices consisting of alternating poly(3,4-ethylenedioxythiophene) (PEDOT) and reduced graphite oxide (rGO) striped microelectrode arrays were fabricated by lithography technology. It has been demonstrated that the organic bioelectronic devices can be used to spatially and temporally manipulate the location and proliferation of the neuron-like pheochromocytoma cells (PC-12 cells).Methods
By coating an electrically labile contact repulsion layer of poly(l-lysine-graft-ethylene glycol) (PLL-g-PEG) on the PEDOT electrode, the location and polarity of the PC-12 cells were confined to the rGO electrodes.Results
The outgrowth of spatially confined bipolar neurites was found to align along the direction of the 20 μm wide electrode. The location of the PC-12 cells can also be manipulated temporally by applying electrical stimulation during the neurite differentiation of PC-12 cells, allowing the PC-12 cells to cross over the boundary between the PEDOT and the rGO regions and construct neurite networks in an unconfined manner where the contact repulsive coating of PLL-g-PEG was removed.Conclusions
This adsorption and desorption of the PLL-g-PEG without and with electrical stimulation can be attributed to the tunable surface properties of the PEDOT microelectrodes, whose surface charge can switch from being negative to positive under electrical stimulation.General significance
The electrically tunable organic bioelectronics reported here could potentially be applied to tissue engineering related to the development and regeneration of mammalian nervous systems. The spatial and temporal control in this device would also be used to study the synapse junctions of neuron–neuron contacts in both time and space domains. This article is part of a Special Issue entitled Organic Bioelectronics — Novel Applications in Biomedicine. 相似文献8.
M. Barra D. Viggiano P. Ambrosino F. Bloisi F.V. Di Girolamo M.V. Soldovieri M. Taglialatela A. Cassinese 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
There is no doubt that future discoveries in the field of biochemistry will depend on the implementation of novel biosensing techniques, able to record biophysiological events with minimal biological interference. In this respect, organic electronics may represent an important new tool for the analysis of structures ranging from single molecules up to cellular events. Specifically, organic field-effect transistors (OFET) are potentially powerful devices for the real-time detection/transduction of bio-signals. Despite this interest, up to date, the experimental data useful to support the development of OFET-based biosensors are still few and, in particular, n-type (electron-transporting) devices, being fundamental to develop highly-performing circuits, have been scarcely investigated.Methods
Here, films of N,N′-1H,1H-perfluorobutyldicyanoperylene-carboxydi-imide (PDIF-CN2) molecules, a recently-introduced and very promising n-type semiconductor, have been evaporated on glass and silicon dioxide substrates to test the biocompatibility of this compound and its capability to stay electrically-active even in liquid environments.Results
We found that PDIF-CN2 transistors can work steadily in water for several hours. Biocompatibility tests, based on in-vitro cell cultivation, remark the need to functionalize the PDIF-CN2 hydrophobic surface by extra-coating layers (i.e. poly-l-lysine) to favor the growth of confluent cellular populations.Conclusions
Our experimental data demonstrate that PDIF-CN2 compound is an interesting organic semiconductor to develop electronic devices to be used in the biological field.General significance
This work contributes to define a possible strategy for the fabrication of low-cost and flexible biosensors, based on complex organic complementary metal-oxide-semiconductor (CMOS) circuitry including both p- (hole-transporting) and n-type transistors. This article is part of a Special Issue entitled Organic Bioelectronics—Novel Applications in Biomedicine. 相似文献9.
V. Karagkiozaki P.G. KaragiannidisM. Gioti P. KavatzikidouD. Georgiou E. GeorgarakiS. Logothetidis 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
An exciting direction in nanomedicine would be to analyze how living cells respond to conducting polymers. Their application for tissue regeneration may advance the performance of drug eluting stents by addressing the delayed stent re-endothelialization and late stent thrombosis.Methods
The suitability of poly (3, 4-ethylenedioxythiophene) (PEDOT) thin films for stents to promote cell adhesion and proliferation is tested in correlation with doping and physicochemical properties. PEDOT doped either with poly (styrenesulfonate) (PSS) or tosylate anion (TOS) was used for films' fabrication by spin coating and vapor phase polymerization respectively. PEGylation of PEDOT: TOS for reduced immunogenicity and biofunctionalization of PEDOT: PSS with RGD peptides for induced cell proliferation was further applied. Atomic Force Microscopy and Spectroscopic Ellipsometry were implemented for nanotopographical, structural, optical and conductivity measurements in parallel with wettability and protein adsorption studies. Direct and extract testing of cell viability and proliferation of L929 fibroblasts on PEDOT samples by MTT assay in line with SEM studies follow.Results
All PEDOT thin films are cytocompatible and promote human serum albumin adsorption. PEDOT:TOS films were found superior regarding cell adhesion as compared to controls. Their nanotopography and hydrophilicity are significant factors that influence cytocompatibility. PEGylation of PEDOT:TOS increases their conductivity and hydrophilicity with similar results on cell viability with bare PEDOT:TOS. The biofunctionalized PEDOT:PSS thin films show enhanced cell proliferation.Conclusions
The application of PEDOT polymers has evolved as a new perspective to advance stents.General significance
In this work, nanomedicine involving nanotools and novel nanomaterials merges with bioelectronics to stimulate tissue regeneration for cardiovascular implants. This article is part of a Special Issue entitled Organic Bioelectronics — Novel Applications in Biomedicine. 相似文献10.
Yuriko Furukawa Akiyoshi Shimada Koichi Kato Hiroo Iwata Keiichi Torimitsu 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Transplantation is one potential clinical application of neural stem cells (NSCs). However, it is very difficult to monitor/control NSCs after transplantation and so provide effective treatment. Electrical measurement using a poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) (PEDOT–PSS) modified microelectrode array (MEA) is a biocompatible, non-invasive, non-destructive approach to understanding cell conditions. This property makes continuous monitoring available for the evaluation/assessment of the development of cells such as NSCs.Methods
A PEDOT–PSS modified MEA was used to monitor electrical signals during NSC development in a culture derived from rat embryo striatum in order to understand the NSC differentiation conditions.Results
Electrical data indicated that NSCs with nerve growth factor (NGF) generate a cultured cortical neuron-like burst pattern while a random noise pattern was measured with epidermal growth factor (EGF) at 4 days in vitro (DIV) and a burst pattern was observed in both cases at 11 DIV indicating the successful monitoring of differentiation differences and developmental changes.Conclusions
The electrical analysis of cell activity using a PEDOT–PSS modified MEA could indicate neural network formation by differentiated neurons. Changes in NSC differentiation could be monitored.General significance
The method is based on non-invasive continuous measurement and so could prove a useful tool for the primary/preliminary evaluation of a pharmaceutical analysis. This article is part of a Special Issue entitled Organic Bioelectronics—Novel Applications in Biomedicine. 相似文献11.
Alwin M.D. Wan Emily M. Chandler Maya Madhavan David W. Infanger Christopher K. Ober Delphine Gourdon George G. Malliaras Claudia Fischbach 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Changes in fibronectin (Fn) matrix remodeling contribute to mammary tumor angiogenesis and are related to altered behavior of adipogenic stromal cells; yet, the underlying mechanisms remain unclear due in part to a lack of reductionist model systems that allow the inherent complexity of cell-derived extracellular matrices (ECMs) to be deciphered. In particular, breast cancer-associated adipogenic stromal cells not only enhance the composition, quantity, and rigidity of deposited Fn, but also partially unfold these matrices. However, the specific effect of Fn conformation on tumor angiogenesis is undefined.Methods
Decellularized matrices and a conducting polymer device consisting of poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS) were used to examine the effect of Fn conformation on the behavior of 3T3-L1 preadipocytes. Changes in cell adhesion and proangiogenic capability were tested via cell counting and by quantification of vascular endothelial growth factor (VEGF) secretion, respectively. Integrin-blocking antibodies were utilized to examine varied integrin specificity as a potential mechanism.Results
Our findings suggest that tumor-associated partial unfolding of Fn decreases adhesion while enhancing VEGF secretion by breast cancer-associated adipogenic precursor cells, and that altered integrin specificity may underlie these changes.Conclusions and general significance
These results not only have important implications for our understanding of tumorigenesis, but also enhance knowledge of cell-ECM interactions that may be harnessed for other applications including advanced tissue engineering approaches. This article is part of a Special Issue entitled Organic Bioelectronics — Novel Applications in Biomedicine. 相似文献12.
Background
Interaction of the plant alkaloid aristololactam-β-d-glucoside and the antitumor drug daunomycin with single stranded RNAs poly(G), poly(I), poly(C) and poly(U) has been investigated.Methods
Biophysical techniques of absorption, fluorescence, competition dialysis, circular dichroism, and microcalorimetry have been used.Results
Absorption and fluorescence studies have revealed noncooperative binding of ADG and DAN to the single stranded RNAs. The binding affinity of ADG varied as poly(G) > poly(I) > > poly(C) > poly(U). The affinity of DAN was one order higher than that of ADG and varied as poly(G) > poly(I) > poly(U) > poly(C). This binding preference was further confirmed by competition dialysis assay. The thermodynamics of the binding was characterised to be favourable entropy and enthalpic terms but their contributions were different for different systems. The major non-polyelectrolytic contribution to the binding revealed from salt dependent data appears to be arising mostly from stacking of DAN and ADG molecules with the bases leading to partial intercalation to single stranded RNA structures. Small negative heat capacity values have been observed in all the four cases.Conclusions
This study presents the comparative structural and thermodynamic profiles of the binding of aristololactam-β-d-glucoside and daunomycin to single stranded polyribonucleotides.General significance
These results suggest strong, specific but differential binding of these drug molecules to the single stranded RNAs and highlight the role of their structural differences in the interaction profile. 相似文献13.
Background
RNA has attracted recent attention for its key role in gene expression and hence targeting by small molecules for therapeutic intervention. This study is aimed to elucidate the specificity of the alkaloid coralyne to poly(G), poly(C), poly(I) and poly(U) in the light of its ability in inducing self-structure in poly(A).Methods
Multifaceted experimental techniques like competition dialysis, absorption, fluorescence, circular dichroism and calorimetry were employed. Salt dependence and temperature dependence of the binding was also elucidated.Results
Results of competition dialysis, absorption and fluorescence studies revealed that coralyne binds strongly to the polypurines, poly(G) and poly(I) compared to the polypyrimidines, poly(U) and poly(C). Partial intercalative binding due to the stacking of the molecules between the bases was envisaged. The binding was predominantly enthalpy driven with favourable entropy term with a large favourable non-electrostatic contribution revealed from salt dependent data and the dissection of the free energy. The heat capacity change of − 125 and − 119 cal/mol K− 1 respectively for poly(G) and poly(I) and the partial enthalpy–entropy compensation phenomenon observed confirmed the involvement of multiple weak noncovalent interactions. Circular dichroism studies provided evidence for significant perturbation of the conformation of the RNAs, but no self-structure induction was evident in any of the polymers under the condition of the study.Conclusions
This study presents a complete structural and thermodynamic profile of coralyne interaction to four single stranded RNA polymers.General significance
The study for the first time elucidates the base specificity of coralyne–RNA complexation at the single stranded level. 相似文献14.
Pavel I. Semenyuk Vladimir I. Muronetz Thomas Haertlé Vladimir A. Izumrudov 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
It is well documented that poly(sulfate) and poly(sulfonate) anions suppress protein thermal aggregation much more efficiently than poly(carboxylic) anions, but as a rule, they denature protein molecules. In this work, a polymer of different nature, i.e. poly(phosphate) anion (PP) was used to elucidate the influence of phosphate groups on stability and thermal aggregation of the model enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH).Methods
Isothermal titration calorimetry and differential scanning calorimetry were used for studying the protein–polyanion interactions and the influence of bound polyanions on the protein structure. The enzymatic activity of GAPDH and size of the complexes were measured. The aggregation level was determined from the turbidity.Results
Highly polymerized PP chains were able to suppress the aggregation completely, but at significantly higher concentrations as compared with poly(styrenesulfonate) (PSS) or dextran sulfate chains of the same degree of polymerization. The effect of PP on the enzyme structure and activity was much gentler as opposed to the binding of dextran sulfate or, especially, PSS that denatured GAPDH molecules with the highest efficacy caused by short PSS chains. These findings agreed well with the enhanced affinity of polysulfoanions to GAPDH.Conclusions
The revealed trends might help to illuminate the mechanism of control of proteins functionalities by insertion of charged groups of different nature through posttranslational modifications.General significance
Practical implementation of the results could be the use of PP chains as promising tools to suppress the proteins aggregation without noticeable loss in the enzymatic activity. 相似文献15.
Laura K. Povlich Jae Cheol Cho Michelle K. Leach Joseph M. Corey Jinsang Kim David C. Martin 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Conjugated polymers have been developed as effective materials for interfacing prosthetic device electrodes with neural tissue. Recent focus has been on the development of conjugated polymers that contain biological components in order to improve the tissue response upon implantation of these electrodes.Methods
Carboxylic acid-functionalized 3,4-ethylenedioxythiophene (EDOTacid) monomer was synthesized in order to covalently bind peptides to the surface of conjugated polymer films. EDOTacid was copolymerized with EDOT monomer to form stable, electrically conductive copolymer films referred to as PEDOT-PEDOTacid. The peptide GGGGRGDS was bound to PEDOT-PEDOTacid to create peptide functionalized PEDOT films.Results
The PEDOT-PEDOTacid-peptide films increased the adhesion of primary rat motor neurons between 3 and 9 times higher than controls, thus demonstrating that the peptide maintained its biological activity.Conclusions
The EDOT-acid monomer can be used to create functionalized PEDOT-PEDOTacid copolymer films that can have controlled bioactivity.General Significance
PEDOT-PEDOTacid-peptide films have the potential to control the behavior of neurons and vastly improve the performance of implanted electrodes. This article is part of a Special Issue entitled Organic Bioelectronics—Novel Applications in Biomedicine. 相似文献16.
S. Kar B. Bagchi B. Kundu S. Bhandary R. Basu P. Nandy S. Das 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Microbial resistance to antibiotics has triggered the development of nanoscale materials as an alternative strategy. To stabilize these particles an inert support is needed.Method
Porous nanomullite developed by sol–gel route is loaded with copper and silver nanoparticle by simple adsorption method. These nanocomposites are characterized using XRD, FTIR, TEM, SEM, EDAX and UV–visible spectrophotometer. Antibacterial activity of these nanocomposites against Gram positive and Gram negative bacteria are performed by bactericidal kinetics, flow cytometry and MTT assay. The underlying mechanisms behind the antimicrobial property and cell death are also investigated by EPR spectroscopy, intracellular ROS measurement and β-galactosidase assay. The cytocompatibility of the nanocomposites is investigated by cell viability (MTT), proliferation (Alamar blue) and wound healing assay of mammalian fibroblast cell line.Results
Nanocomposites show a fairly uniform distribution of metal nanoparticle within mullite matrix. They show excellent antibacterial activity. Metal ions/nanoparticle is found to be released from the materials (CM and SM). Treated cells manifested high intracellular oxidative stress and β-galactosidase activity in the growth medium. The effect of nanocomposites on mammalian cell line depends on exposure time and concentration. The scratch assay shows normal cell migration with respect to control.Conclusion
The fabricated nanoparticles possess diverse antimicrobial mechanism and exhibit good cytocompatibility along with wound healing characteristics in mouse fibroblast cell line (L929).General significance
The newly synthesized materials are promising candidates for the development of antimicrobial ceramic coatings for biomedical devices and therapeutic applications. 相似文献17.
Li Liu T. Kevin Hitchens Qing Ye Yijen Wu Brent Barbe Devin E. Prior Wendy F. Li Fang-Cheng Yeh Lesley M. Foley Daniel J. Bain Chien Ho 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Superparamagnetic iron-oxide nanoparticles are useful as contrast agents for anatomical, functional and cellular MRI, drug delivery agents, and diagnostic biosensors. Nanoparticles are generally cleared by the reticuloendothelial system (RES), in particular taken up by Kupffer cells in the liver, limiting particle bioavailability and in-vivo applications. Strategies that decrease the RES clearance and prolong the circulation residence time of particles can improve the in-vivo targeting efficiency.Methods
Intralipid 20.0%, an FDA approved nutritional supplement, was intravenously administered in rats at the clinical dose (2 g/kg) 1 h before intravenous injection of ultra-small superparamagnetic iron-oxide (USPIO) or micron-sized paramagnetic iron-oxide (MPIO) particles. Blood half-life, monocyte labeling efficiency, and particle biodistribution were assessed by magnetic resonance relaxometry, flow cytometry, inductively-coupled plasma MS, and histology.Results
Pre-treatment with Intralipid resulted in a 3.1-fold increase in USPIO blood half-life and a 2-fold increase in USPIO-labeled monocytes. A 2.5-fold increase in MPIO blood half-life and a 5-fold increase in MPIO-labeled monocytes were observed following Intralipid pre-treatment, with a 3.2-fold increase in mean iron content up to 2.60 pg Fe/monocyte. With Intralipid, there was a 49.2% and 45.1% reduction in liver uptake vs. untreated controls at 48 h for USPIO and MPIO, respectively.Conclusions
Intralipid pre-treatment significantly decreases initial RES uptake and increases in-vivo circulation and blood monocyte labeling efficiency for nano- and micron-sized superparamagnetic iron-oxide particles.General significance
Our findings can have broad applications for imaging and drug delivery applications, increasing the bioavailability of nano- and micron-sized particles for target sites other than the liver. 相似文献18.
Background
Conjugated polymers (CPs) have been used for creating bioimaging tools or biosensors that provide a direct link between spectral signal and different biological processes. The detection schemes of these sensors are mainly employing the efficient light harvesting properties or the conformation sensitive optical properties of the CPs. Hence, the presence of biomolecules or biological events can be detected through fluorescence resonance energy transfer (FRET) between the CP and an acceptor molecule, or through their impact on the conformation of the conjugated backbone, which is seen as an alteration of the optical properties of the CP.Scope of the review
In this review, the utilization of CPs for sensitive detection of DNA and protein conformational changes will be presented. The main part will be focused on the specific binding of CPs to protein deposits associated with protein misfolding diseases, such as Alzheimer's disease (AD), and the discovery that tailor-made CPs can be used for in vivo optical imaging of protein aggregates will be discussed.Major conclusions
The unique optical properties of CPs can be used as molecular tools for sensitive detection of genetic material and for characterization of the pathological hallmarks associated with protein misfolding disorders, such as AD.General significance
CPs are novel molecular tools that can be used for sensitive bioimaging of biological processes and these tools offer the possibility to study biological events in a complementary fashion to conventional techniques.This article is part of a Special Issue entitled Nanotechnologies - Emerging Applications in Biomedicine. 相似文献19.
Petri Ihalainen Himadri Majumdar Anni Määttänen Shaoxia Wang Ronald Österbacka Jouko Peltonen 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
Cheap, reliable, point-of-care diagnostics is a necessity for the growing and aging population of the world. Paper substrate and printing method, combined together, are the cheapest possible method for generating high-volume diagnostic sensor platforms. Electrical transduction tools also minimize the cost and enhance the simplicity of the devices.Methods
Standard surface characterization techniques, namely contact angle measurements, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) were used to analyze the growth of the organic thiol layers on top of the printed metal electrodes on paper substrates. The results were compared with those obtained by impedimetric electrical characterization method.Results
This article reports the fabrication and characterization of printed metal electrodes and their functionalization by organic layers on paper and plastic substrates for biosensing and diagnostic applications. Impedimetric measurement is proposed as a simple, yet elegant, method of characterization of the organic layer growth.Conclusions
Very good correlation was observed between the results of organic layer growth from different measurement methods, justifying the use of paper as a substrate, printing as a method for fabricating metal and organic layers and impedance as a suitable measurement method for hand-held diagnostic devices.General significance
This result paves the way for the fabrication of more advanced bio-recognition layers for bio-affinity sensors using a printing technology that is compatible with flexible and cheap paper substrates. This article is part of a Special Issue entitled Organic Bioelectronics — Novel Applications in Biomedicine. 相似文献20.
Tao Hu Dongxia Li Jun Wang Qingqing Wang Yangui Liang Yanlei Su Guanghui Ma Zhiguo Su Shihua Wang 《Biochimica et Biophysica Acta (BBA)/General Subjects》2012