Aug
13
Tue
2013
Plenary Talk: Biosensor and Single Cell Manipulation using Nanopipettes @ Amriteshwari Hall
Aug 13 @ 10:06 am – 10:49 am

NaderNader Pourmand, Ph.D.
Director, UCSC Genome Technology Center,University of California, Santa Cruz


Biosensor and Single Cell Manipulation using Nanopipettes

Approaching sub-cellular biological problems from an engineering perspective begs for the incorporation of electronic readouts. With their high sensitivity and low invasiveness, nanotechnology-based tools hold great promise for biochemical sensing and single-cell manipulation. During my talk I will discuss the incorporation of electrical measurements into nanopipette technology and present results showing the rapid and reversible response of these subcellular sensors  to different analytes such as antigens, ions and carbohydrates. In addition, I will present the development of a single-cell manipulation platform that uses a nanopipette in a scanning ion-conductive microscopy technique. We use this newly developed technology to position the nanopipette with nanoscale precision, and to inject and/or aspirate a minute amount of material to and from individual cells or organelle without comprising cell viability. Furthermore, if time permits, I will show our strategy for a new, single-cell DNA/ RNA sequencing technology that will potentially use nanopipette technology to analyze the minute amount of aspirated cellular material.

Invited Talk: Nanomaterials for ‘enzyme-free’ biosensing @ Amriteshwari Hall
Aug 13 @ 2:17 pm – 2:35 pm

SatheeshSatheesh Babu T. G., Ph.D.
Associate Professor, Department of Sciences, School of Engineering, Amrita University, Coimbatore, India


Nanomaterials for ‘enzyme-free’ biosensing

Enzyme based sensors have many draw backs such as poor storage stability, easily affected by the change in pH and temperature and involves complicated enzyme immobilization procedures.  To address this limitation, an alternative approach without the use of enzyme, “non-enzymatic” has been tried recently. Choosing the right catalyst for direct electrochemical oxidation / reduction of a target molecule is the key step in the fabrication of non-enzymatic sensors.

Non-enzymatic sensors for glucose, creatinine, vitamins and cholesterol are fabricated using different nanomaterials, such as nanotubes, nanowires and nanoparticles of copper oxide, titanium dioxide, tantalum oxide, platinum, gold and graphenes. These sensors selectively catalyse the targeted analyte with very high sensitivity. These nanomaterials based sensors combat the drawbacks of enzymatic sensors.

Satheesh

Delegate Talk: Designing electrochemical label free immunosensors for cytochrome c using nanocomposites functionalized screen printed electrodes
Aug 13 @ 3:53 pm – 4:06 pm
Delegate Talk: Designing electrochemical label free immunosensors for cytochrome c using nanocomposites functionalized screen printed electrodes

Pandiaraj Manickam, Niroj Kumar Sethy, Kalpana Bhargava, Vepa Kameswararao and Karunakaran Chandran


Designing electrochemical label free immunosensors for cytochrome c using nanocomposites functionalized screen printed electrodes

Release of cytochrome c (cyt c) from mitochondria into cytosol is a hallmark of apoptosis, used as a biomarker of mitochondrial dependent pathway of cell death (Kluck et al. 1997; Green et al. 1998). We have previously reported cytochrome c reductase (CcR) based biosensors for the measurement of mitochondrial cyt c release (Pandiaraj et al. 2013). Here, we describe the development of novel label-free, immunosensor for cyt c utilizing its specific monoclonal antibody. Two types of nanocomposite modified immunosensing platforms were used for the immobilization of anti-cyt c; (i) Self-assembled monolayer (SAM) functionalized gold nanoparticles (GNP) in conducting polypyrrole (PPy) modified screen printed electrodes (SPE) (ii) Carbon nanotubes (CNT) incorporated PPy on SPE. The nanotopologies of the modified electrodes were confirmed by scanning electron microscopy (SEM). Cyclic voltammetry, electrochemical impedance spectroscopy (EIS) were used for probing the electrochemical properties of the nanocomposite modified electrodes. Method for cyt c quantification is based on the direct electron transfer between Fe3+/Fe2+-heme of cyt c selectively bound to anti-cyt c modified electrode. The Faradaic current response of these nanoimmunosensor increases with increase in cyt c concentration. The procedure for cyt c detection was also optimized (pH, incubation times, and characteristics of electrodes) to improve the analytical characteristics of immunosensors. The analytical performance of anti-cyt c biofunctionalized GNP-PPy nanocomposite platform (detection limit 0.5 nM; linear range: 0.5 nM–2 μM) was better than the CNT-PPy (detection limit 2 nM; linear range: 2 nM-500nM). The detection limits were well below the normal physiological concentration range (Karunakaran et al. 2008). The proposed method does not require any signal amplification or labeled secondary antibodies contrast to widespread ELISA and Western blot. The immunosensors results in simple and rapid measurement of cyt c and has great potential to become an inexpensive and portable device for conventional clinical immunoassays.

Delegate Talk: Novel Cell-Based Biosensors for High Throughput Toxin Detection and Drug Screening Applications @ Amriteshwari Hall
Aug 13 @ 4:08 pm – 4:23 pm
Delegate Talk:  Novel Cell-Based Biosensors for High Throughput Toxin Detection and Drug Screening Applications @ Amriteshwari Hall | Vallikavu | Kerala | India

Anupama Natarajan, James Hickman and Peter Molnar


Novel Cell-Based Biosensors for High Throughput Toxin Detection and Drug Screening Applications

Over the last decade there has been focus on the development of cellbased biosensors to detect environmental toxins or to combat the threats of biological warfare. These sensors have been shown to have multiple applications including understanding function and behaviour at the cellular and tissue levels, in cell electrophysiology and as drug screening tools that can eliminate animal testing. These factors make the development of cell-based biosensors into high throughput systems a priority in pharmacological, environmental and defence industries (Pancrazio J J et al. 1999, Kang G et al. 2009, Krinke D et al. 2009). We have developed a high through-put in vitro cell-silicon hybrid platform that could be used to analyze both cell function and response to various toxins and drugs. Our hypothesis was that by utilizing surface modification to provide external guidance cues as well as optimal growth conditions for different cell types (Cardiac and Neuronal), we could enhance the information output and content of such a system. An intrinsic part of this study was to create ordered or patterned functional networks of cells on Micro-electrode arrays (MEA). Such engineered networks had a two-fold purpose in that they not only aided in a more accurate analysis of cell response and cell and tissue behaviour, but also increased the efficiency of the system by increasing the connectivity and placement of the cells over the recording electrodes. Here we show the response of this system to various toxins and drugs and the measurement of several vital cardiac parameters like conduction velocity and refractory period (Natarajan A et al. 2011)

Aug
14
Wed
2013
Delegate Talk: Development of Supercritical Fluid Chromatography methods for the replacement of existing USP Normal phase liquid chromatography methods @ Amriteshwari Hall
Aug 14 @ 12:01 pm – 12:11 pm
Delegate Talk: Development of Supercritical Fluid Chromatography methods for the replacement of existing USP Normal phase liquid chromatography methods @ Amriteshwari Hall | Vallikavu | Kerala | India

Syed Salman Lateef and Vinayak A K


Development of Supercritical Fluid Chromatography methods for the replacement of existing USP Normal phase liquid chromatography methods

Normal phase liquid chromatography methods often have long run times and involve environmentally toxic/costly solvents. Supercritical chromatography methods on the other hand are faster, inexpensive, and eco-friendly. The low viscous supercritical carbon dioxide operates at high flow rates compared to LC without losing separation efficiency. In this work, SFC methods are developed to replace three United States Pharmacopeial (USP) normal phase achiral methods – prednisolone, tolazamide and cholecalciferol. System suitability parameters of the normal phase method are compared against the SFC method. Precision, linearity and robustness of the new SFC methods are demonstrated. SFC methods were found to be cost effective in terms of analysis time and solvent savings. The SFC method does not require purchase and disposal of expensive environmentally hazardous chemicals. Hence, the newly developed SFC method provides a faster and safer solution.