Multiplexed detection of cancer biomarkers using an optical biosensor

Early detection of cancer is important in administering timely treatment and increasing cancer survival rates. For early cancer detection one can use biomarkers, which are characteristics that can be objectively measured or evaluated as indicators of normal or pathogenic processes. In our study we study three protein biomarkers: carcinoembryonic antigen (CEA), interleukin-6 (IL-6) and extracellular protein kinase A (ECPKA), which have been implicated in various types of human cancer. The main objective of this project is to develop a biosensor for detection of multiple cancer biomarkers. To detect these protein biomarkers high affinity ssDNA aptamers are being selected. Aptamers are short single stranded DNAs with an ability to bind to various targets with high affinity and specificity which selected by SELEX (Systemic Evolution of Ligands through Exponential enrichment) [2]. Ultimately, aptamers against each of the biomarker will be conjugated to magnetic nanoparticles to capture biomarkers from biological fluids. Another aptamer is proposed to be conjugated to quantum dots for quantitation of biomarkers when analyzed on spectrometer

Multiplexed detection of cancer biomarkers using an optical biosensor

Early detection of cancer is important in administering timely treatment and increasing cancer survival rates. For early cancer detection one can use biomarkers, which are characteristics that can be objectively measured or evaluated as indicators of normal or pathogenic processes. In our study we study three protein biomarkers: carcinoembryonic antigen (CEA), interleukin-6 (IL-6) and extracellular protein kinase A (ECPKA), which have been implicated in various types of human cancer. The main objective of this project is to develop a biosensor for detection of multiple cancer biomarkers. To detect these protein biomarkers high affinity ssDNA aptamers are being selected. Aptamers are short single stranded DNAs with an ability to bind to various targets with high affinity and specificity which selected by SELEX (Systemic Evolution of Ligands through Exponential enrichment) [2]. Ultimately, aptamers against each of the biomarker will be conjugated to magnetic nanoparticles to capture biomarkers from biological fluids. Another aptamer is proposed to be conjugated to quantum dots for quantitation of biomarkers when analyzed on spectrometer

Evidence for early life in Earth’s oldest hydrothermal vent precipitates

Although it is not known when or where life on Earth began, some of the earliest habitable environments may have been submarine-hydrothermal vents. Here we describe putative fossilized microorganisms that are at least 3,770 million and possibly 4,280 million years old in ferruginous sedimentary rocks, interpreted as seafloor-hydrothermal vent-related precipitates, from the Nuvvuagittuq belt in Quebec, Canada. These structures occur as micrometre-scale haematite tubes and filaments with morphologies and mineral assemblages similar to those of filamentous microorganisms from modern hydrothermal vent precipitates and analogous microfossils in younger rocks. The Nuvvuagittuq rocks contain isotopically light carbon in carbonate and carbonaceous material, which occurs as graphitic inclusions in diagenetic carbonate rosettes, apatite blades intergrown among carbonate rosettes and magnetite–haematite granules, and is associated with carbonate in direct contact with the putative microfossils. Collectively, these observations are consistent with an oxidized biomass and provide evidence for biological activity in submarine-hydrothermal environments more than 3,770 million years ago

Defects of welded joints of the wire, causing breakages during drawing

Based on the research experience of the wire raptures all weld defects are systematized. These stydies were done during the rough-the middle wire drawing and bronzing. The defects which most often occur breakages of wire were listed and requirements to the weld seam were established

Picomolar detection of thrombin with fiber-optic ball resonator sensor using optical backscatter reflectometry

A ball resonator, positioned on the tip of an optical fiber, has been developed as a biosensor for the prototypic detection of thrombin. The device was fabricated with a fast and repeatable CO2 laser splicing method, followed by gold-sputtering and functionalization for the measurement of various protein concentrations. The ball resonator acts as a weak interferometer with a return loss below − 50 dB, and it is interrogated with an optical backscatter reflectometer measuring the reflection spectrum. We report here a sample presenting high sensitivity (1273.74 nm/RIU, RIU = refractive index units), which allows protein detection in the range 0.4–100 pM, with a limit of detection of 1.56 pM in logarithmic response

The influence of renal anemia on cardiac remodelling in chronic glomerulonephritis

The relation between renal diseases and cardiovascular morbidity is known since Richard Bright times, who was the first researcher on morphology of the left ventricle hypertrophy (LVH) in renal diseases. Since these times, an abundant research was done on LVH as one of the leading risk factors for heart failure development in chronic glomerulonephritis (CGN) and of the role of anemia in renal diseases. However, until recently it is not completely known of the role of anemia in formation of structural cardiovascular changes in CGN.Aim. To study the influence of anemia on the development of various types of LV remodelling in CGN patients of predialysis stage.Material and methods. Totally, 137 patients studied (70 men and 67 women) at the age 16-64 y. o. (mean age — 34,7±13,0) with established CGN diagnosis at predialysis stage. Anemia was diagnosed based on KDIGO criteria of 2012. Clinical assessment included: complaints, anamnesis; physical examination with anthropometric parameters and blood pressure measurement; laboratory-instrumental assessment for diagnosis verification; biochemical measurement of serum total protein, creatinine, fibrinogen, lipid profile, C-reactive protein. For structural changes of the heart evaluation, we applied electro- and echocardiographical study. LVH and remodelling types were defined according to RCS criteria. For LVH evaluation, we calculated myocardial mass index of the LV, and higher normal limit we used was for women 109 g/m2, and for men 124 g/m2. Statistics was performed on personal computer with Excel software and “Statistica 6.0”.Results. If anemia existed in CGN patient, there was significantly increased thickness of interventricular septum — 0,9±0,1 cm vs 0,8±0,2 cm (p<0,05) and of indexed LV mass — 115±44 g/m2 vs 96±41 g/m2 (p<0,01) comparing to CGN patients without anemia.Conclusion. Structural changes of cardiovascular system in CGN persons does occur even in predialysis period. If anemia present, there is tendency for increase of excentric LVH and interventricular septum

Cost-Effective Fiber Optic Solutions for Biosensing

In the last years, optical fiber sensors have proven to be a reliable and versatile biosensing tool. Optical fiber biosensors (OFBs) are analytical devices that use optical fibers as transducers, with the advantages of being easily coated and biofunctionalized, allowing the monitorization of all functionalization and detection in real-time, as well as being small in size and geometrically flexible, thus allowing device miniaturization and portability for point-of-care (POC) testing. Knowing the potential of such biosensing tools, this paper reviews the reported OFBs which are, at the moment, the most cost-effective. Different fiber configurations are highlighted, namely, end-face reflected, unclad, D- and U-shaped, tips, ball resonators, tapered, light-diffusing, and specialty fibers. Packaging techniques to enhance OFBs’ application in the medical field, namely for implementing in subcutaneous, percutaneous, and endoscopic operations as well as in wearable structures, are presented and discussed. Interrogation approaches of OFBs using smartphones’ hardware are a great way to obtain cost-effective sensing approaches. In this review paper, different architectures of such interrogation methods and their respective applications are presented. Finally, the application of OFBs in monitoring three crucial fields of human life and wellbeing are reported: detection of cancer biomarkers, detection of cardiovascular biomarkers, and environmental monitoring

Functionalized etched tilted fiber Bragg grating aptasensor for label-free protein detection

An aptasensor based on etched tilted fiber Bragg grating (eTFBG) is developed on a single-mode optical fiber targeting biomolecule detection. TFBGs were chemically etched using hydrofluoric acid (HF) to partially remove the fiber cladding. The sensor response was coarsely interrogated, resulting on a sensitivity increase from 1.25 nm/RIU (refractive index unit) at the beginning of the process, up to 23.38 nm/RIU at the end of the etching, for a RI range from 1.3418 to 1.4419 RIU. The proposed aptasensor showed improved RI sensitivity as compared to the unetched TFBG, without requiring metal depositions on the fiber surface or polarization control during the measurements. The proposed sensor was tested for the detection of thrombin-aptamer interactions based on silane-coupling surface chemistry, with thrombin concentrations ranging from 2.5 to 40 nM. Functionalized eTFBGs provided a competitive platform for biochemical interaction measurements, showing sensitivity values ranging from 2.3 to 3.3 p.m./nM for the particular case of thrombin detection