Label-free biosensors for the detection and quantification of cardiovascular risk markers

This paper presents a biosensor implementation for the detection of protein molecules using specific antibodies. Affinity sensors allow the detection and quantification of target molecules in complex mixtures by affinity-based interactions. Immobilized antibody molecules are the probes that bind to specific protein molecules (targets) in biological fluids. In this study, inter-digitated electrodes in the form of capacitance on glass slide were designed, fabricated and used to measure the changes in the dielectric properties of the inter-digitated capacitances. Our results in this study present that with a careful design of micro-interdigitated capacitors, a wider dynamic range and higher sensitivity can be achieved for the detection and quantification of C-Reeactive Protein

A novel single-chip RF-voltage-controlled oscillator for bio-sensing applications

A novel interdigiated capacitance (IDC) based affinity biosensor system is presented that detects C-Reactive Protein (CRP), a risk marker for cardiovascular diseases, and transmit the information to a distance location wirelessly. The biosensor system consist of a voltage controlled oscillator (VCO) and an IDC. In the presence of CRP the capacitance of the IDC changes and this directly reflects to the oscillation frequency of the VCO. In the presence of 800 ng/ml antigen the frequency of the system shifts from 1.9438 GHz to 1.94175 GHz and with 64 ug/ml frequency shifts from 1.95975 GHz to 1.94875 GHz with -120 dBc/Hz phase noise

Development of a new biosensor array and lab-on-a-chip for portable applications using a label-free detection method

The detection and quantification of cardiac biomarkers in serum is crucial to diagnose patients in the early stage of a disease. The recent advances in microfluidics technology can improve diagnostics by reducing the application time and integrating several clinical analysis into a single, portable device called lab-on-a-chip (LOC). The development of such immunosensing LOC is a major thrust of the rapidly growing bionanotechnology industry. It involves a multidisciplinary research effort encompassing microfluidics, microelectronics and biochemistry. This thesis work focused on the development of immunoassays on microfabricated gold inter-digitated transducers (IDT) on silica and glass substrates. The concept of label-free, affinity-based biosensing is introduced with a special emphasis to impedance spectroscopy. Different protocols involving the covalent immobilization of cancer risk marker (human epidermal growth factor, hEGFR) and cardiac risk marker proteins C reactive protein (CRP), interleukin (IL6) and nicotinamide phosphoribosyltransferase (Nampt) single stranded deoxyribonucleic acid were investigated. For this, IDTs were fabricated using integrated circuit (IC) fabrication processes providing compatibility for the integration of electronic circuits, for single-chip and lab-on-a-chip biosensing applications. The thesis also involves development of a poly dimethylsiloxane (PDMS)-based fluidic system comprising on-chip actuated mechanism for multi-target immunosensing applications. The fluidic flow is controlled by an applied hydraulic pressure on the micropump. Label-free affinity type sensing was carried out using two different biological recognition elements (a) immunosensing approach using antibodies for hEGFR and IL-6 was employed and the function of the LOC was analyzed for detection of hEGFR and IL-6 as model analytes. A detection limit of 0.1ng/ml of hEGFR and IL-6 in serum was obtained without any signal amplification. (b) label-free affinity-based methodology using ssDNA aptamers specific for Nampt to develop an aptasensor and obtained a detection limit of 1 ng/ml in serum for Nampt, which is the most sensitive detection range with the application of the aptamer for Nampt

A new nanocrystalline diamond-based biosensor for the detection of cardiovascular risk markers

In this paper, a new method to probe associative interactions of C-reactive protein (CRP) antigen with CRP antibody immobilized on a gold-interdigitated diamond electrodes was investigated. The CRP antigen detection was performed by capacitive/dielectric-constant measurements. Our results showed that the dynamic detection range using optimized conditions for a given antibody concentration (100 μg/ml) was found to be in the range 25-800 ng/ml of CRP-antigen. Biosensor developed in this study can be potentially used for detection of elevated CRP levels in suspected subjects for early diagnosis

A new lab-on-chip transmitter for the detection of proteins using RNA aptamers

A new RNA aptamer based affinity biosensor for CReactive Protein (CRP), a risk marker for cardiovascular disease was developed using interdigitated capacitor (IDC), integrated in Voltage Controlled Oscillator (VCO) and output signal is amplified using Single Stage Power Amplifier (PA) for transmitting signal to receiver at Industrial, Scientific and Medical (ISM) band. The Lab-on-Chip transmitter design includes IDC, VCO and PA. The design was implemented in IHP 0.25μm SiGe BiCMOS process; post-CMOS process was utilized to increase the sensitivity of biosensor. The CRP was incubated between or on interdigitated electrodes and the changes in capacitance of IDC occurred. In blank measurements, the oscillation frequency was 2.464GHz whereas after RNA aptamers were immobilized on open aluminum areas of IDC and followed by binding reaction processed with 500pg/ml CRP solution, the capacitance shifted to 2.428GHz. Phase noise is changed from -114.3dBc/Hz to -116.5dBc/Hz

Sensitive detection of Nampt(PBEF/Visfatin)in human serum for point-of-care applications using aptamer based capacitive biosensor

NAMPT is a multifunctional protein, also known as visfatin or pre-B cell colony-enhancing factor, which exists as the rate-limiting intracellular enzyme for nicotinamide adenine dinucleotide (NAD) synthesis starting from nicotinamide [1]. The plasma Nampt levels are reported to have correlation with obesity and obese related metabolic disease, such as Type 2 diabetes mellitus (T2DM), cardiovascular diseases [2] and hyperlipidemia [3] due to association with lipoprotein and cholesterol. Therefore, sensitive detection of Nampt potentially enable accurate diagnosis of T2DM, cardiovascular and hyperlipidemia diseases. In this study, for the first time, we developed an ssDNA aptamer that specifically bind Nampt (Kd=72.52 nM) in human serum by systematic evolution of ligands by exponential enrichment (SELEX) process. Nampt-specific ssDNA aptamers were then applied as the recognition molecules for the development of a capacitive biosensor using non-Faradaic impedance spectroscopy (nFIES), which converts the biological binding event into a quantifiable signal for sensitive and efficient detection of the Nampt (Fig. 1). The interaction of aptamer-Nampt induced the change in dielectric properties, charge distribution, and conductivity. The limit of detection was 1 ng/ml with a dynamic range of upto 50 ng/ml in serum and this range is under the clinical requirements both in the normal Nampt levels, which is 15.8 ng/ml, and in the T2DM patients level, which is 31.9 ng/ml. This assay system for Nampt detection using aptamers is a potential alternative approach for applications in clinical studies and Point-Of-Care health technologies

Development of a new biosensor array and lab-on-a-chip for portable applications using a label-free detection method

The detection and quantification of cardiac biomarkers in serum is crucial to diagnose patients in the early stage of a disease. The recent advances in microfluidics technology can improve diagnostics by reducing the application time and integrating several clinical analysis into a single, portable device called lab-on-a-chip (LOC). The development of such immunosensing LOC is a major thrust of the rapidly growing bionanotechnology industry. It involves a multidisciplinary research effort encompassing microfluidics, microelectronics and biochemistry. This thesis work focused on the development of immunoassays on microfabricated gold inter-digitated transducers (IDT) on silica and glass substrates. The concept of label-free, affinity-based biosensing is introduced with a special emphasis to impedance spectroscopy. Different protocols involving the covalent immobilization of cancer risk marker (human epidermal growth factor, hEGFR) and cardiac risk marker proteins C reactive protein (CRP), interleukin (IL6) and nicotinamide phosphoribosyltransferase (Nampt) single stranded deoxyribonucleic acid were investigated. For this, IDTs were fabricated using integrated circuit (IC) fabrication processes providing compatibility for the integration of electronic circuits, for single-chip and lab-on-a-chip biosensing applications. The thesis also involves development of a poly dimethylsiloxane (PDMS)-based fluidic system comprising on-chip actuated mechanism for multi-target immunosensing applications. The fluidic flow is controlled by an applied hydraulic pressure on the micropump. Label-free affinity type sensing was carried out using two different biological recognition elements (a) immunosensing approach using antibodies for hEGFR and IL-6 was employed and the function of the LOC was analyzed for detection of hEGFR and IL-6 as model analytes. A detection limit of 0.1ng/ml of hEGFR and IL-6 in serum was obtained without any signal amplification. (b) label-free affinity-based methodology using ssDNA aptamers specific for Nampt to develop an aptasensor and obtained a detection limit of 1 ng/ml in serum for Nampt, which is the most sensitive detection range with the application of the aptamer for Nampt

Merged SAR and Optical

The map package files (merged.mpk) were prepared and can be opened by Arc Gis 10.8.2 and above versions. The map package data files include the SAR data (RISAT-1 from ISRO-Bhoonidhi) in HH,HV- polarizations, DEM ( USGS ) and IRS LISS III (Bhuvan-NRSC) data with the 30m spatial resolution were downloaded from the respective websites. Geology data in 1:50,000 scale is downloaded from GSI Bhukosh.The resolution merged data of Optical and SAR data has been prepared using Brovey transform in ERDAS 2015 software. The output file have advantages of both optical and microwave features. Extracted the Lineaments(.shp) from the coupled data of merged SAR and improved and verified with the DEM, Optical, SAR and Geology data sets. All these data generation and Statistical calculation done with the help of ArcGIS software. ArcGIS guide will help to create shape files, Attribute table calculations of length, classification. Azumutal trend calculations of each lineaments done using Split lines and other geometric calculations giving the trend of each lineament and finally export the map (All .jpg files).Rose diagrams was prepared based on the trend of lineaments with the help of Rockworks 17 software. The generated Azimuthal trend data in lineament shape file can be import to linears - utilites - Rose diagram. I was prepared Rose diagram of different class of lineaments using frequency calculation method.Lineaments are the linear geological features can extend from few meters to hundreds of kms. Geologically lineaments are either structural or stratigraphical, typically it will comprise fault, fold axis, bedding contacts, dyke intrusions, shear zone or a straight coast line. Mapping lineaments using remote sensing is economical, faster can act as a preliminary study. Generally lineaments have been mapped using the optical remote sensing data such as Landsat, Resourcesat etc. For India, Lineaments were mapped using the LISS III and LISS IV of Resourcesat-1 & 2 at a scale of 1:50k. However in tropical region like India, limited exposure of ground due to vegetation cover, lineaments may go unnoticed in optical remote sensing data. This problem can be overcome by Synthetic Aperture Radar (SAR) data, which can penetrate ground significantly. With the launch of RISAT-1satelite, data availability of SAR data is immense for Indian region. Aim of this study to explore the SAR data and merged SAR and optical data for lineament mapping.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Merged SAR and Optical

The map package files were prepared and can be opened by Arc Gis 10.8.2 and above versions. The data files include the SAR data in HH,HV- polarizations, DEM and IRS LISS III data with the 30m spatial resolution which are download from Bhuvan-NRSC, Geology data from Geological Survey of india (Bhukosh). The resolution merged data of Optical and SAR data has been prepared using Brovey transform in ERDAS 2015 software. Rose diagrams based on the trend of lineaments are prepared with the help of Arc GIS 10.8.2 tools and Rockworks 17 software. Lineaments are the linear geological features can extend from few meters to hundreds of kms. Geologically lineaments are either structural or stratigraphical, typically it will comprise fault, fold axis, bedding contacts, dyke intrusions, shear zone or a straight coast line. Mapping lineaments using remote sensing is economical, faster can act as a preliminary study. Generally lineaments have been mapped using the optical remote sensing data such as Landsat, Resourcesat etc. For India, Lineaments were mapped using the LISS III and LISS IV of Resourcesat-1 & 2 at a scale of 1:50k. However in tropical region like India, limited exposure of ground due to vegetation cover, lineaments may go unnoticed in optical remote sensing data. This problem can be overcome by Synthetic Aperture Radar (SAR) data, which can penetrate ground significantly. With the launch of RISAT-1satelite, data availability of SAR data is immense for Indian region. Aim of this study to explore the SAR data and merged SAR and optical data for lineament mapping.THIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV