Chemiluminescence based immunoassay for the detection of heroin and its metabolites

Introduction: Continuous use of opiates causes drug-related illnesses, which poses an alarming situation to develop sensitive detection platform. In this study, a highly sensitive and reliable chemiluminescence immunoassay (CI) has been developed for the detection of heroin and its major metabolites in spiked urine samples. Methods: To develop robust immunoassay, monoacetyl morphine-bovine serum albumin (MAM-BSA) conjugate was synthesized and characterized thoroughly by physicochemical techniques. The anti-MAM antibodies were developed, labeled with horseradish peroxidase (HRP) and immunoassay was developed to detect the presence of target drug in spiked urine samples. Results: A competitive CI was developed, where heroin, MAM, morphine, and codeine concentration were ranged from 0-1000 ng/ mL in spiked urine samples and limit of detection were 80, 95, 90, 75 pg/ mL. Conclusion: The developed CI is highly sensitive, specific, point of care, cost-effective and can be used as a routine technique for quantitative analysis for screening of narcotic drugs

Probing interactions and phase separations of proteins, colloids and polymers with light scattering

The broad objective of my research is to investigate the physical characteristics and interactions of macromolecules and nanoparticles, and the corresponding effects on their phase separation behavior using static and dynamic light scattering (SLS & DLS). Light scattering provides a non-invasive technique for monitoring the in-situ behavior of solutes in solution, including solute interactions, sizes, shapes, aggregation kinetics and even rheological properties of condensed phases. Initially, we investigated lysozyme solutions for the presence of preformed aggregates and clusters that can distort the kinetics of protein crystal nucleation studies in this important model system for protein crystallization. We found that both undersaturated and supersaturated lysozyme solutions contained population of large, pre-existing protein aggregate. Separating these clusters and analyzing their composition with gel chromatography indicated that these clusters represented pre-formed lysozyme aggregates, and not extrinsic protein contamination. We investigated the effect of chaotropic versus kosmotropic ions (water structure breakers vs. structure makers) on the hydration layer and hydrodynamic interactions of hen egg white lysozyme. Surprisingly, neither chaotropic nor kosmotropic ions affected the protein hydration layer. Salt-effects on direct and hydrodynamic protein interactions were determined as function of the solutions ionic strength and temperature. Using both static and dynamic light scattering, we investigated the nucleation of gold nanoparticles forming from supersaturated gold sols. We observed that two well separated populations of nuclei formed essentially simultaneously, with sizes of 3nm vs. several tens of nanometer, respectively. We explore the use of lysozyme as tracer particle for diffusion-base measurements of electrolyte solutions. We showed that the unusual stability of lysozyme and its enhanced colloidal stability enable viscosity measurement of salts solutions at high salt concentration, over a wide range of pH values and temperatures for the common tracer particle polystyrene flocculates. We applied dynamic light scattering to measure the viscoelastic responses of polystyrene probe particles embedded in solutions and gels of two different polymers: polyacrylamide (PAAm) and poly-N-isopropylacrylamide (poly-NiPAAm)

A Strategic Review on Carbon Quantum Dots for Cancer-Diagnostics and Treatment

The understanding of the genesis of life-threatening cancer and its invasion calls for urgent development of novel technologies for real-time observations, early diagnosis, and treatment. Quantum dots (QDs) grabbed the spotlight in oncology owing to their excellent photostability, bright fluorescence, high biocompatibility, good electrical and chemical stability with minimum invasiveness. Recently, carbon QDs (CQDs) have become popular over toxic inorganic QDs in the area of bioimaging, biosensing, and drug delivery. Further, CQDs derived from natural sources like biomolecules and medicinal plants have drawn attention because of their one-pot, low-cost and ease of synthesis, along with remarkable tunable optical properties and biocompatibility. This review introduces the synthesis and properties of CQDs derived from natural sources, focusing on the applicability of CQD-based technologies as nano-theranostics for the diagnosis and treatment of cancer. Furthermore, the current issues and future directions for the transformation of CQDs-based nanotechnologies to clinical applications are highlighted

Fabrication and characterization of Al/Ta thin films as metal junctions for solar cell applications

In the present work, the effect of deposition time (10 min, 20 min, and 30 min) on the structural, morphological, and electrical properties of Al/Ta thin films has been investigated. The XRD and microscopy results revealed that the thin films exhibit a bcc structure, with a strong (110) preferred orientation and followed a columnar growth with grain sizes lower than 100 nm. Thin film with 20-min deposition time exhibits less average roughness and better morphology than 10-min and 30-min. Further, the average resistance was smallest for thin films with 20-min of deposition time along with the optical reflectance between 50 and 85% in wavelength region of 400–1000 nm. The Al/Ta thin film can be employed as an excellent back-contact material for thinfilm solar cells due to its improved crystallinity, reflectance, and lower resistivity

Large Area Few-Layer Hexagonal Boron Nitride as a Raman Enhancement Material

Increasingly, two-dimensional (2D) materials are being investigated for their potential use as surface-enhanced Raman spectroscopy (SERS) active substrates. Hexagonal Boron Nitride (hBN), a layered 2D material analogous to graphene, is mostly used as a passivation layer/dielectric substrate for nanoelectronics application. We have investigated the SERS activity of few-layer hBN film synthesized on copper foil using atmospheric pressure chemical vapor deposition. We have drop casted the probe molecules onto the hBN substrate and measured the enhancement effect due to the substrate using a 532 nm excitation laser. We observed an enhancement of ≈103 for malachite green and ≈104 for methylene blue and rhodamine 6G dyes, respectively. The observed enhancement factors are consistent with the theoretically calculated interaction energies of MB > R6G > MG with a single layer of hBN. We also observed that the enhancement is independent of the film thickness and surface morphology. We demonstrate that the hBN films are highly stable, and even for older hBN films prepared 7 months earlier, we were able to achieve similar enhancements when compared to freshly prepared films. Our detailed results and analyses demonstrate the versatility and durability of hBN films for SERS applications

Abstracts of National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020

This book presents the abstracts of the papers presented to the Online National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020 (RDMPMC-2020) held on 26th and 27th August 2020 organized by the Department of Metallurgical and Materials Science in Association with the Department of Production and Industrial Engineering, National Institute of Technology Jamshedpur, Jharkhand, India. Conference Title: National Conference on Research and Developments in Material Processing, Modelling and Characterization 2020Conference Acronym: RDMPMC-2020Conference Date: 26–27 August 2020Conference Location: Online (Virtual Mode)Conference Organizer: Department of Metallurgical and Materials Engineering, National Institute of Technology JamshedpurCo-organizer: Department of Production and Industrial Engineering, National Institute of Technology Jamshedpur, Jharkhand, IndiaConference Sponsor: TEQIP-