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Catechol Biosensor Based on Gold Nanoparticle Modified Tetrabutyl ammonium tetrafluoroborate Doped Polythiophene
No full textTetra butyl ammonium tetra fluoroborate (TBATFB) doped polythiophene films have been polymerized galvano-statically which were then modified with soium citrate capped gold nanoparticles (AuNPs) using dip coating method. Catechol biosensor was fabricated using laccase enzyme. ITO/Pth and ITO/Pth/AuNPs/Lac bioelectrodes were characterized using scanning electron microscopy (SEM), UV-Visible spectroscopy and electrochemical techniques. Absorbance for ITO/Pth/AuNPs/Lac bioelectrodes was monitored at 410 nm as a function of catechol concentration and pH. Cyclic voltammetric studies of ITO/Pth electrodes showed quasi-reversible behavior when recorded in sodium acetate buffer, which later turned into reversible behavior on modification with gold nanoparticles. ITO/Pth/AuNPs/Lac bioelectrodes showed maximum oxidation potential for enzymatic reaction of catechol at -0.2 V, with linear range upto 0.8 mM and regression coefficient (R2) of 0.988. Sensitivity and Km values were found to be 3.7 x 10-5 mA/mM and 0.22 mM respectively, with response time of about 6-8 s
Suman SINGH, aS. Praveen KUMAR, bD. V. S. JAIN, a*M. L. SINGL
Active Marker based Kinematic and Spatio-Temporal Gait Measurement System using LabVIEW
Get PDFThis study presents an automated, easy to use, cost-effective, patient-friendly, active marker based gait measurement (GM) system for 2-D tracking and extraction of spatio-temporal parameters of human gait. Active markers, consisting of visible light-emitting diodes (LEDs), were positioned at anatomical landmarks to measure coordinated kinematics of human joints.Acquired image data were processed and analyzed using LabVIEW vision for determination of spatio-temporal parameters
Knowledge base generation and its implementation for control of above knee prosthetic device based on SEMG and knee flexion angle
No full textAdvanced intelligent knee prosthesis for trans-femoral amputees requires a versatile control strategy and associated control algorithm. Control strategy was evolved by mapping surface EMG (SEMG) from four muscles of healthy lower limb of a unilateral trans-femoral amputee and knee flexion angles (KFA) during various phases of a gait cycle. The SEMG and KFA are calibrated to three walking speeds modes i.e., slow, normal and fast. Sensor mechanisms feeds real-time data to controller to generate an appropriate control output signal based on available knowledgebase which calculates the patient's gait parameters i.e., KFA and SEMG from associated muscles during the corresponding phase of walk. Important aspect of control strategy is the development of knowledgebase proves that the SEMG signal generates recognisable pattern for change in walking speed when signals were analysed in time and frequency domain. These patterns were quantified and utilised for controlling electro-pneumatic knee joint
Multiple-laser Flash Shadowgraphy System for Terminal Studies of Small-caliber Projectiles
No full textA multiple-laser flash shadowgraphy system has been innovatively designed and developed to study the terminal effects of projectiles. The system has been designed based on modulated laser diodes operated at low voltage and current. In order to study the ballistics effects of small arms, an exposure time of the order of a few hundreds ns and a delay time of the order of a few tens of μs are needed. An ultrashort pulse generator has been developed to provide the exposure and delay time pulses. The developed system has been integrated with a field lens assembly and camera assembly. To record the shadowgraphs, a target is placed near the center of the field lens and a bullet is fired from a fixed gun. The system is described, and experimental results and conclusions are reported
Electrochemical synthesis of poly(aniline-co-fluoroaniline) films and their application as humidity sensing material
No full textIn the present manuscript, humidity sensing properties of a copolymer, poly(aniline-co-fluoroaniline) have been reported. The copolymer was prepared on indium-tin-oxide coated glass plates as well as platinum surface in the form of films using electrochemical technique (versus standard calomel electrode) in acidic medium. Synthesis of copolymer films was supported by Fourier transform infra-red, ultraviolet–visible, scanning electron microscope and cyclic voltammetry techniques. Molecular weight and electrical conductivity of these films were measured at different temperature. Polyaniline and poly(2-fluoroaniline) films were also synthesized using the same technique to compare the data with copolymer film. On exposure to humid atmosphere, the response behaviour of copolymer film exhibited a change in resistance with respect to relative humidity (RH). This copolymer film was found to be most sensitive in the 30–65% RH range and shows a linear behaviour with in this range
Cross-Linker Mediated Biofunctionalization of Single Wall Carbon Nanotubes with Glucose Oxidase
No full textCovalent attachment of biomolecules to the surface of carbon nanotubes provides an architecture for three dimensional arrays of sensor molecules (i.e. enzymes) for potential biosensor application. Present work reports a simple two-step reaction for immobilization of glucose oxidase on single walled carbon nanotubes (SWCNTs). This method is as efficient as conventional methods for biofunctionalization of SWCNT with enzyme. Moreover, it overcomes structural losses of SWCNTs and minimizes reaction steps involved in this process previously. Cross linkers 1-Ethyl-3-(3-dimethylaminopropyl)-carbodiimide and N-hydrosuccinimide were employed for omitting the acylation step through formation of stable intermediates. The inference of efficacy of the present methodology is based on the final outcome of the reaction, in terms of the number of glucose oxidase molecules immobilized on SWCNT. Biofunctionalization of SWCNTs was characterized by fourier transform infra red spectroscopy, ultraviolet-visible spectroscopy, elemental analysis and atomic force microscop
Role of Adenine and Guanine Sites in Hole Hopping in DNA Nanowire
No full textTransfer integrals for oligos with different bases have been calculated using INDO/Koopman's approximation to unveil the charge transport mechanism in DNA. The sequences, G(A)nG, n = 1, 2, …, 10; G(A)xG(A)yG, x + y = 9; and G(A)xG(A)y G(A)zG, x + y + z = 8, were employed to interpret the Guanine (G) and Adenine(A) hopping. Adenine hopping is found to be faster in G(A)nG sequences with longer Adenine bridges (n ≥ 3). Inserting G-bases in between G(A)10G led to a decrease in the value of transfer integrals. Close analysis has revealed that bridge closer to 3′-end forms a hopping bottleneck; however, the presence of bridge at 5′-end enhances the charge transfer through A-hopping. Further insertion of single G sites in G(A)xG(A)yG (where x + y = 9) reduces the transfer integrals, thus explaining the hampering of A-hopping. Hence, sequences of the type G(A)nG, n > 3, are better suited for their application as molecular wire. Finally, studies on the effect of flipping of bases, i.e. flipping G:C to C:G on transfer integrals, have revealed that helical distortions and conformational changes due to sequence variations lead to changes in coupling, which is highly unpredictable
24 bit seismic processor for analyzing extra large dynamic range signals for early warning.
Get PDFModified design is presented of existing 24 bit seismic data recorder comprising PC –architecture using PCI bus, ISA bus, and PC 104 bus in a single module to develop a flexible measurement set up. Paper elaborates use of building blocks [Disk on chip (DoC), GPS based timing unit, signal-processing module, and efficient software packages] worked out in visual C++ to develop compact sized instrument for quick decision-making with minimum error detection of true events. Paper describes Ethernet connectivity use for data downloading in a laptop without interruption of event data acquisition. Software packages for conversion of recorded data into SUDS and SEISAN formats have been realized and incorporated
Determination of Location and Orientation of 3-Axis Accelerometer for Detecting Gait phase, Duration and Speed of Human Motion for Development of Prosthetic Knee
Get PDFThe paper discusses results of experiments
carried out at healthy individuals with an aim to establish
an in-house developed sensor mechanism using ADXL 330
accelerometer. The sensor was developed in view to measure
gait phases (heel strike & toe off), gait duration and gait
speed. These findings were useful in understanding the
range of normal gait though accelerometer and further used
for control of indigenously developed artificial electronic
knee
Lower Body Gait Analysis using Biometrics Twin Axis Goniometers
No full textThe joint angles of the lower limb are important parameters in evaluating the ability and stability
of the walk. The individuals differ in their walking styles because of differences in flexion/
extension angles of hip, knee and ankle joints. The simplest method of measuring joint angles is
placing goniometers along these joints. Although this method is prone to error and have very
little scientific information contained other than joint angle values, different phases and subphases of gait can be categorized in terms of these angles. The joint angle measured from the
normal functioning lower limb of the patient can be used as part of a feedback mechanism that
guides the prosthetic mechanism employed on the affected/amputated limb to produce very
similar angular movement to execute stable walking pattern. Authors measure human joint
movement angles using Biometrics Twin Axis Goniometers in order to analyze the joint angle
patterns and mapping them for normal gait. These angles information can be used as a feedback
in controlling the flexion/extension of prosthetic