Use Of Microchips Research Articles

Neural implant for the treatment of multiple sclerosis

The methods used to treat various neurological diseases are evolving. The facilities provided by the technology have led to creation of new treatment opportunities. Neuromodulation is one of these important methods. By definition, the neuromodulation is a change in neural activity which occurs by stimulating a specific area of nervous system. The mentioned stimulation can be electrical, magnetic, or chemical. This method is used in various diseases, such as stroke, Parkinson's, Alzheimer's, and amyotrophic lateral sclerosis (ALS). Multiple sclerosis (MS) is no exception in this regard and methods including the neurofeedback and transcranial magnetic stimulation (TMS) are used to treat various complications of the MS. One aspect of neuromodulation is the use of neural implant, which is applied nowadays, especially in the Parkinson's disease, and the use of microchips and prostheses to treat various symptoms in different neurological diseases has received significant attention. Although neural implant has been exploited to improve the symptoms of MS, they appear to have much greater potential to improve the condition of patients with MS. It seems that more attention to the symptoms of MS, on the one hand, and a new approach to the pathogenesis of this disease and considering it as a connectomopathy, on the other hand, can provide new opportunities for application of this method in the treatment of MS.

Application of microchip and infrared thermography for monitoring body temperature of beef cattle kept on pasture.

The monitoring of body temperature is important for the diagnosis of the physiological state of the animal, being dependent on available methods and their applicability within production systems. This work evaluated techniques to monitor the body temperature of beef cattle kept on pasture and their ability to predict internal temperature. Twenty-three adult bovine females were monitored for six months, and collection data carried out in eleven campaigns (D0-D10) twelve days apart. During collections, the surface temperatures of ear base (ET, oC) and ocular globe (OGT, oC) were measured by infrared thermography, and the subcutaneous temperature (ST, oC) was measured with the use of transponder containing an implantable microchip. Rectal temperature (RT, oC) was considered as a reference for body temperature. Temperature and Humidity Index (THI), Black Globe Temperature and Humidity Index (BGHI) and Radiant Heat Load (RHL, W/m2) were calculated. ET (33.32 ± 0.12 °C), ST (36.10 ± 0.07 °C), OGT (37.40 ± 0.06 °C) and RT (38.83 ± 0.03 °C) differed significantly (P˂0.05). There was positive correlation of RT with OGT (r = 0.392), ET (r = 0.264) and ST (r = 0.236) (P˂0.05). Considering the bioclimatic indicators, the highest magnitude correlations were observed between ET and THI (r = 0.71), ET and BGHI (r = 0.65), and ET and RHL (r = 0.48). The use of microchip represented a practical method, but with limited predictability. On the other hand, infrared thermography proved to be safe and non-invasive, presenting greater precision for inference of internal body temperature. ET was more influenced by meteorological conditions.

The Use of Lab on a Chip Devices to Evaluate Infectious Biofilm Formation and Assess Antibiotics and Nano Drugs Treatments

The microfluidics devices are identified as Lab On a Chip (LOC) and they consist of a network of microchannels that are compose by different sections, chambers, columns and reservoirs [1]. The LOC application to study organisms is an emerging field where the benefits of miniaturization of the system offer new opportunities to study and sense different bioprocesses. In addition, microorganisms form surface-adherent community structures called biofilms and these biofilms play a critical role in wound infections. Microbial biofilms have inherent defense and survival mechanisms including: avoidance of host inflammatory cells, resistance to antibiotics, and dynamic cell-cell communication pathways with gene exchange (Quorum Sensing), which inhibit wound healing [2]. Also nanoparticles targeting anti-biofilm therapy have gained recognition due to their unique features. In this work we propose LOC as a platform for the formation of infectious biofilm in skin wounds and assess new treatments with antibiotics and nano drugs and these drugs have antimicrobial and anti-biofilm properties. The microdevices were built with glass base and polydimethylsiloxane (PDMS) cover. PDMS was mixed with curing agent in a 10:1 ratio and then the mixture was placed under vacuum to remove air bubbles, poured onto the SU8-mold and cured in an oven at 80 °C overnight. The microchip design microchannels (Figure 1) allows for higher throughput with multiple channels are located in one chip (parallelized measurements). Each microchannel has 11 culture chambers with a height of 100 µm and an internal volume of 5.36 µL with. The microchannels were washed with 70% ethanol and were disinfected using NaOH (0.5 mol L-1) for 30 minutes. Pseudomonas aeruginosa and Propionibacterium acnes were used in a continuous culture either as a single culture or as co-culture in the microchip as a bioreactor for biofilm formation in the microchannels. After 3 days of culture good cell adhesions to the substrate and biofilm formation inside the microchannels were observed. Different concentrations of nanoparticles of silver, gold and antibiotics were evaluated for the inhibition of the infections biofilm. After 48 h of each anti-biofilm treatment condition the physiological characteristics were analyzed by transcriptomics (RNAm sequencing) and the morphological characterization of biofilm architecture was evaluated by Scanning Electron Microscopy (SEM) and Confocal Scanning Laser Microscopy (CSLM).The results of this study show that the use of microchip as a culture system allows a good biofilm formation and is a valuable tool for quickly screening of antimicrobial activity of nano drugs in biofilms. This microchip can be used in drug testing and biomedical applications. 1- Whitesides, G.M., (2006). The origins and the future of microfluidics. Nature. 442(7101):368-373 2- Alvarado-Gomez, E., Martínez-Castañon, G., Sanchez-Sanchez, R., Ganem-Rondero, A., Yacaman, M. J., & Martinez-Gutierrez, F. (2018). Evaluation of anti-biofilm and cytotoxic effect of a gel formulation with Pluronic F-127 and silver nanoparticles as a potential treatment for skin wounds. Materials Science and Engineering: C, 92:621-630. Figure 1

No DNR Tattoo for Me, Thanks

No DNR Tattoo for Me, Thanks

Nanotechnology in Diagnosis: A Review

The fast pace of today’s world has presented several challenges in the area of healthcare. Depression, hypertension, diabetes, cancers and several infectious diseases are just some of the common outcomes associated with the high speed stress-filled lifestyle. Early diagnosis has been the goal for prompt arrest and management of these health conditions. This has been a challenge in recent times. However, great scientific advancement with improved potential in medical diagnosis has equally been a giant stride in times like these. Early disease detection even before symptoms’ presentation, improved imaging of internal body structure, as well as ease of diagnostic procedures, have been developed with the help of a new branch of laboratory medicine termed nanodiagnostics. Use of microchips, biosensors, nanorobots, nano identification of single celled structures, and microelectromechanical systems are current techniques being developed for use in nanodiagnostics. This piece of write up takes a panoramic view of available nanotechnological advances in current use for medical diagnosis and projecting into future possibilities and potentials for an improved health care delivery.

Preliminary Studies on the Use of Pit Tags to Evaluate Abalone Restocking

ABSTRACT The evaluation of abalone (Haliotis spp.) restocking programs might be improved by the use of microchips attached to seeds [ca. 20–30mmshell length (SL)]. Preliminary studies were conducted to standardize thismethodology and to assess tag retention and the potential impacts of tagging red abalone (Haliotis rufescens) seeds (initial averages: 26 mm SL, 2.5 g total weight) with passive integrated transponder (PIT) tags (9×2mm, Biomark, HPR Plus Reader). Tags were placed in previously made grooves in the shells and glued with a cyanoacrylate adhesive fast cured with sodium bicarbonate. Laboratory trials showed that metabolic rate increased in tagged seeds compared with untagged controls (t = 4.74, P = 0.009) immediately after the tagging procedure, but this effect was not significant after 3 h (t= 1.43, P = 0.23). Food (Macrocystis pyrifera) consumption after 24 h was similar by seeds marked with PIT tags, plastic tags, both tags, and untagged controls (F= 0.12, P = 0.94). Tag retention and survival...

Assessment of platelet‐derived thrombogenicity with the total thrombus‐formation analysis system in coronary artery disease patients receiving antiplatelet therapy

Accurate evaluation of thrombogenicity helps to prevent thrombosis and excessive bleeding. The total thrombus-formation analysis system (T-TAS) was developed for quantitative analysis of platelet thrombus formation by the use of microchips with thrombogenic surfaces (collagen, platelet chip [PL-chip]; collagen plus tissue factor, atherome chip [AR-chip]). We examined the utility of the T-TAS in the assessment of the efficacy of antiplatelet therapy in patients with coronary artery disease (CAD). In this cross-sectional study, 372 consecutive patients admitted to the cardiovascular department were divided into three groups: patients not receiving any antiplatelet therapy (control, n = 56), patients receiving aspirin only (n = 69), and patients receiving aspirin and clopidogrel (n = 149). Blood samples were used for the T-TAS to measure the platelet thrombus-formation area under the curve (AUC) at various shear rates (1500 s(-1) [PL18 -AUC10 ] and 2000 s(-1) [PL24 -AUC10 ] for the PL-chip; 300 s(-1) [AR10 -AUC30 ] for the AR-chip). The on-clopidogrel platelet aggregation was measured by the use of P2Y12 reaction units (PRUs) with the VerifyNow system. The mean PL24 -AUC10 levels were 358 ± 111 (± standard deviation) (95% confidence interval [CI] 328.9-387.1) in the control group, 256 ± 108 (95% CI 230.5-281.5) in the aspirin group, and 113 ± 91 (95% CI 98.4-127.6) in the aspirin/clopidogrel group. In the aspirin/clopidogrel group, the PL24 -AUC10 was higher in poor metabolizers (PMs) with cytochrome P450 2C19(CYP2C19) polymorphisms (152 ± 112, 95% CI 103.4-200.6) than in the non-PM group (87 ± 74, 95% CI 73.8-100.2). Our findings suggest that the PL24 -AUC10 level measured by the T-TAS is a potentially suitable index for the assessment of antiplatelet therapy in CAD patients.

The impact of commonly used air filters in eliminating the exposure to secondhand smoke constituents.

Exposure to secondhand tobacco smoke (SHS) also known as environmental tobacco smoke (ETS) has been well established scientifically as a human health hazard. Despite this and warnings from health agencies, concerns over the economic impact of smoke-free bans have limited political resolve to enact these regulations. Arguments against smoke-free bans include the contention that air filters can eliminate the health risks from SHS exposure. In this study, we assessed the effectiveness of air filters (MERV 4 and MERV 8) commonly used in homes and businesses in reducing the concentrations of total suspended particulates, fine particles and carbon monoxide from SHS as a measure of their potential to reduce the toxicity associated with SHS exposure. Our results demonstrate that these filters are not effective at reducing carbon monoxide levels or PM 2.5, which have been correlated with human health toxicity/disease. Thus, our findings, from a public health perspective, do not support the use of common air filters as a viable alternative to smoke-free bans.

Recent advances in affinity capillary electrophoresis for binding studies.

The present review covers recent advances and important applications of affinity capillary electrophoresis (ACE). It provides an overview about various ACE types, including ACE-MS, the multiple injection mode, the use of microchips and field-amplified sample injection-ACE. The most common scenarios of the studied affinity interactions are protein-drug, protein-metal ion, protein-protein, protein-DNA, protein-carbohydrate, carbohydrate-drug, peptide-peptide, DNA-drug and antigen-antibody. Approaches for the improvements of ACE in term of precision, rinsing protocols and sensitivity are discussed. The combined use of computer simulation programs to support data evaluation is presented. In conclusion, the performance of ACE is compared with other techniques such as equilibrium dialysis, parallel artificial membrane permeability assay, high-performance affinity chromatography as well as surface plasmon resonance, ultraviolet, circular dichroism, nuclear magnetic resonance, Fourier transform infrared, fluorescence, MS and isothermal titration calorimetry.

Probing fluid flow using the force measurement capability of optical trapping

Interest in microfluidics is rapidly expanding and the use of microchips as miniature chemical reactors is increasingly common. Microfluidic channels are now complex and combine several functions on a single chip. Fluid flow details are important but relatively few experimental methods are available to probe the flow in confined geometry. We use optical trapping of a small dielectric particle to probe the fluid flow. A highly focused laser beam attracts particles suspended in a liquid to its focal point. A particle can be trapped and then repositioned. From the displacement of the trapped particle away from its equilibrium position one estimates the external force acting on the particle. The stiffness (spring constant) of the optical trap is low thus making it a sensitive force measuring device. Rather than using the optical trap to position and release a particle for independent velocimetry measurement, we map the fluid flow by measuring the hydrodynamic force acting on a trapped particle. The flow rate of a dilute aqueous electrolyte flowing through a plastic microchannel (W×H×L=5mm×0.4mm×50mm) was mapped using a small silica particle (1μm diameter). The fluid velocity profile obtained experimentally is in very good agreement with the theoretical prediction. Our flow mapping approach is time efficient, reliable and can be used in low-opacity suspensions flowing in microchannels of various geometries.

Recent advances in the application of capillary electromigration methods for food analysis and Foodomics

In this work, the analysis of foods and food components using capillary electromigration methods is reviewed. The present work presents and discusses the main CE applications performed in Food Science and Technology including the new field of Foodomics, reviewing recent results on food quality and safety, nutritional value, storage, bioactivity, as well as applications of CE for monitoring food interactions and food processing. The CE analysis of a large variety of food-related molecules with different chemical properties, including amino acids, peptides, proteins, phenolic compounds, carbohydrates, DNA fragments, vitamins, toxins, pesticides, additives, and other minor compounds is described. The use of microchips, CE-MS, and chiral-CE in food analysis is also discussed as well as other current and foreseen trends in this area of research. Following the previous review by Castro-Puyana et al. (Electrophoresis, 2012, 33, 147–167), the current review covers the papers that were published from February 2011 to February 2013.

Microchip-based electrochemical detection for monitoring cellular systems

The use of microchip devices to study cellular systems is a rapidly growing research area. There are numerous advantages of using on-chip integrated electrodes to monitor various cellular processes. The purpose of this review is to give examples of advancements in microchip-based cellular analysis, specifically where electrochemistry is used for the detection scheme. These examples include on-chip detection of single-cell quantal exocytosis, electrochemical analysis of intracellular contents, the ability to integrate cell culture/immobilization with electrochemistry, and the use of integrated electrodes to ensure cell confluency in longer-term cell culture experiments. A perspective on future trends in this area is also given.

The natural ambiguity of the notion of ‘natural', and how to overcome it

In this paper I will explore the ramification of the distinction between fact and values in order to show that human values enter in various ways in both science and (nano)technologies without violating Hume's fact/value distinction. Among the nanotechnologies, I will discuss the case study provided by the use of microchips implanted under our skin: though they do not obviously overcome the limits of the natural laws (intended in the descriptive sense), their application might in principle jeopardize our ethical principles in a way that is more powerful than previously existing ‘macrotechnology'. This greater power depends on the fact that the properties of the macroworld depend on the ‘nanoworld', but not conversely.

Digital Foundations: The Making of Silicon-Gate Manufacturing Technology

From 1960 onward, the expanding use of microchips played a major role in the establishment of the digital world. This paper examines the dominant manufacturing technology for microchips in this period: silicon-gate MOS technology . It reconstructs the development of silicon gate technology from its emergence at Bell Labs, Fairchild, General Micro-electronics, and Hughes in the mid-1960s to its stabilization at Intel and its augmentation with ion implantation at Mostek in the early 1970s. This article argues that silicon gate emerged at the convergence point of three contextual logics: material logic (the opportunities and constraints offered by materials and material capabilities), market logic (the dynamics of semiconductor markets), and competitive logic (the imperative of surviving in a fiercely competitive industry). Thus, this article is intended as a contribution to materials-centered studies and to recent interest on the connection between intentionality and materiality in technology and science.

Rapid Determination of Sexually Transmitted Infections by Real-time Polymerase Chain Reaction Using Microchip Analyzer

Development of non expensive and time-saving techniques based on the polymerase chain reaction (PCR) is of great importance for modern diagnostics. We considered a new approach for PCR determination of a variety of sexually transmitted infections using microchip analyzer “AriaDNA”, which had been tested using clinical samples in several medical institutions of St. Petersburg (Russia). The use of microchips containing lyophilized PCR reagents allows reducing significantly time of analysis and the number of manipulations thus preventing possible sample contamination.

Recent advances in the application of capillary electromigration methods for food analysis and Foodomics

The analysis of food components using capillary electromigration methods is reviewed in this work. Papers that were published from February 2009 to February 2011 are included following the previous review by Herrero et al. (Electrophoresis, 2010, 31, 205-228). The analysis of amino acids, biogenic amines, peptides, proteins, DNAs, carbohydrates, phenols, polyphenols, pigments, toxins, pesticides, vitamins, additives, small organic and inorganic ions and other compounds found in foods and beverages are reviewed, as well as those applications of CE for monitoring food interactions and food processing. The use of microchips, CE-MS and chiral-CE in food analysis is also discussed as well as other current and foreseen trends in this area of research including new developments in Foodomics.

Recent approaches in sensitive enantioseparations by CE

The latest strategies and instrumental improvements for enhancing the detection sensitivity in chiral analysis by CE are reviewed in this work. Following the previous reviews by García-Ruiz et al. (Electrophoresis 2006, 27, 195-212) and Sánchez-Hernández et al. (Electrophoresis 2008, 29, 237-251; Electrophoresis 2010, 31, 28-43), this review includes those papers that were published during the period from June 2009 to May 2011. These works describe the use of offline and online sample treatment techniques, online sample preconcentration techniques based on electrophoretic principles, and alternative detection systems to UV-Vis to increase the detection sensitivity. The application of the above-mentioned strategies, either alone or combined, to improve the sensitivity in the enantiomeric analysis of a broad range of samples, such as pharmaceutical, biological, food and environmental samples, enables to decrease the limits of detection up to 10⁻¹² M. The use of microchips to achieve sensitive chiral separations is also discussed.

Recent novel MEKC applications to analyze free amino acids in different biomatrices: 2009–2010

This report intends to provide an updated overview of the most important methodological developments of MEKC in the field of qualitative/quantitative analysis of free amino acids in different matrices. A good number of articles published in the years 2009-2010 addresses the main applications of such procedures together with their advantages and/or drawbacks. The usefulness of chiral CE selective methods for the separation of D-amino acids in biological and food samples and the use of microchips, as well as other foreseen trends in different areas, are also discussed.

Photoinduced cleaning of water-soluble dyes on patterned superhydrophilic/superhydrophobic substrates

Herein we present a novel but simple method to fabricate photoinduced cleaning substrates with patterned superhydrophobic hierarchical silicon cone arrays (SCAs) and superhydrophilic TiO(2) nanorod clusters (TNCs). In our experiment, the photoinduced cleaning properties of the obtained substrate are investigated by repeatedly adsorbing and decomposing rhodamine B (RhB) molecules for at least six cycles. In addition, we demonstrate that the low-surface-energy coating on the superhydrophobic areas is stable, resulting in the high wettability contrast being well preserved during the renewal process. This straightforward method may open up new possibilities for the practical use of microchips with patterned superhydrophobic and superhydrophilic areas.

Recent advances in the application of capillary electromigration methods for food analysis and Foodomics

The use of capillary electromigration methods to analyze foods and food components is reviewed in this work. Papers that were published during the period April 2007 to March 2009 are included following the previous review by García-Cañas and Cifuentes (Electrophoresis, 2008, 29, 294-309). These works include the analysis of amino acids, biogenic amines, peptides, proteins, DNAs, carbohydrates, phenols, polyphenols, pigments, toxins, pesticides, vitamins, additives, small organic and inorganic ions and other compounds found in foods and beverages, as well as those applications of CE for monitoring food interactions and food processing. The use of microchips, CE-MS, chiral-CE as well as other foreseen trends in food analysis are also discussed including their possibilities in the very new field of Foodomics.