Ananya Srivastava

Paper based diagnostics for personalized health care: Emerging technologies and commercial aspects.

Personalized health care (PHC) is being appreciated globally to combat clinical complexities underlying various metabolic or infectious disorders including diabetes, cardiovascular, communicable diseases etc. Effective diagnoses majorly depend on initial identification of the causes which are nowadays being practiced in disease-oriented approach, where personal health profile is often overlooked. The adoption of PHC has shown significantly improved diagnoses in various conditions including emergency, ambulatory, and remote area. PHC includes personalized health monitoring (PHM), which is its integral part and may provide valuable informations on various clinical conditions. In PHC, bio-fluids are analyzed using various diagnostic devices including lab based equipment and biosensors. Among all types of biosensing systems, paper based biosensors are commercially attracted due to its portability, easy availability, cheaper manufacturing cost, and transportability. Not only these, various intrinsic properties of paper has facilitated the development of paper based miniaturized sensors, which has recently gained ASSURED (Affordable, Sensitive, Specific, User-friendly, Rapid and Robust, Equipment free, Deliverable to all end-users) status for point of care diagnosis in miniaturized settings. In this review, importance of paper based biosensors and their compatibility for affordable and low cost diagnostics has been elaborated with various examples. Limitations and strategies to overcome the challenges of paper biosensor have also been discussed. We have provided elaborated tables which describe the types, model specifications, sensing mechanisms, target biomarkers, and analytical performance of the paper biosensors with their respective applications in real sample matrices. Different commercial aspects of paper biosensor have also been explained using SWOT (Strength, Weakness, Opportunities, Threats) analysis.

Chitosan: An undisputed bio-fabrication material for tissue engineering and bio-sensing applications

Biopolymers have been serving the mankind in various ways since long. Over the last few years, these polymers have found great demand in various domains which includes bio medicine, tissue engineering, bio sensor fabrications etc. because of their excellent bio compatibility. In this context, chitosan has found global attention due to its environmentally benign nature, biocompatibility, biodegradability, and ease of availability. In last one decade or so, extensive research in active biomaterials, like chitosan has led to the development of novel delivery systems for drugs, genes, and biomolecules; and regenerative medicine. Additionally, chitosan has also witnessed its usage in functionalization of biocompatible materials, nanoparticle (NP) synthesis, and immobilization of various bio-recognition elements (BREs) to form active bio-surfaces with great ease. Keeping these aspects in mind, we have written a comprehensive review which aims to acquaint its readers with the exceptional properties of chitosan and its usage in the domain of biomedicine, tissue engineering, and biosensor fabrication. Herein, we have briefly explained various aspects of direct utilization of chitosan and then presented vivid strategies towards formulation of chitosan based nanocomposites for biomedicine, tissue engineering, and biosensing applications.

Gold Nanoparticles and Nanocomposites in Clinical Diagnostics Using Electrochemical Methods

Progress and development in clinical diagnostics certainly focus upon the advances in the nanomaterials, particularly gold nanoparticles (AuNPs) that offer promise to solve the biocompatible and sensitive detection systems. This paper focuses on the recent application of AuNPs in clinical diagnosis. Various important methods of AuNPs synthesis and their application in clinical detection of various biomolecules using electrochemical detection methods have been described. AuNPs alone and in various composites are also described based on the various biosensors design recently published for the detection of cancer biomarkers, proteins, bacteria, and cancer cells. The effect of AuNPs type and size in clinical detection has also been briefly illustrated.

Bioinspired Composite Materials: Applications in Diagnostics and Therapeutics

Evolution-optimized specimens from nature with inimitable properties, and unique structure–function relationships have long served as a source of inspiration for researchers all over the world. For instance, the micro/nanostructured patterns of lotus-leaf and gecko feet helps in self-cleaning, and adhesion, respectively. Such unique properties shown by creatures are results of billions of years of adaptive transformation, that have been mimicked by applying both science and engineering concepts to design bioinspired materials. Various bioinspired composite materials have been developed based on biomimetic principles. This review presents the latest developments in bioinspired materials under various categories with emphasis on diagnostic and therapeutic applications.

Marine Biomaterials in Therapeutics and Diagnostic

Marine organisms are constituted of compounds with several properties and characteristics. In the last decade lot of biomaterials like various types of polymers and bioactive ingredients have been identified, isolated, and characterized. These biomaterials have a vast range of applications in the medical sector including controlled drug delivery, tissue engineering, and diagnostic device etc. In this chapter, biomaterials have been defined and classified in general, followed by an account of mainly various polymers like collagen, chitin, chitosan, chondroitin sulfate, hyaluronic acid, alginate, biosilica, calcium carbonate and phosphate. Their structure, source, and application in the medical field have been discussed. A brief account of bioactive compounds as therapeutic agents has also been given. Marine biomaterials are also emerging as promising materials for the development of biosensors for medical diagnostics. This chapter also discusses biosensors and the role of biomaterials from marine origin in the development of biosensors for medical diagnostics. The chapter concludes with the scopes of the biomaterials in near future.

Electrochemical Immunosensors: Fundamentals and Applications in Clinical Diagnostics

Abstract Immunosensors are the affinity-based biosensing devices that have enormous potential for the next-generation bioanalytical systems. Usually, the components of these self-content devices include biorecognition element, transducers, and the readout systems, where biorecognition systems perceive the physical signals, transducers convert observed input to the quantifiable electrical signals, and the readout systems show the measured signals. For immunosensing, various transducers are used, including electrochemical, optical, and piezoelectric. Usually, these transducers are modified before using in immunosensing platforms, which essentially works on the formation of antigen–antibody complexes. Among all types of the immunosensors, electrochemical immunosensors are widely accepted because of its specificity and high accuracy. Such immunosensors are usually assessed by various bioanalytical techniques for its diagnostic performances. This chapter summarizes the analytical techniques that are generally used to characterize the electrochemical immunosensors and various advanced approaches, i.e., electrochemical lateral flow assays, colorimetric immunosensing, redox cycling, and receptor–ligand–receptor binding bifunctional signal amplification–based approaches have been described with adequate numbers of illustrations. In addition to this, it also highlights various applications of electrochemical immunosensors in clinical diagnostics.

Evolving trends in bio/chemical sensor fabrication incorporating bimetallic nanoparticles

Biosensor designing took a giant leap in its path of evolution after its merger with a wing of nanotechnology. Dramatic properties like high surface area to volume ratio, enhanced chemical and optical properties of nanoscale materials have revolutionized sensor technology in terms of their analytical performance. Many metallic nanoparticles (MeNPs) like gold, silver, platinum, palladium nanoparticles, etc. have been tremendously exploited for improving sensor performance. Over the years, there has been slow but steady shift in nanoscience research with an aim to explore composite MeNPs like bimetallic, trimetallic nanoparticles, etc. So far, these engineered nanoparticles are shown to possess multifunctional properties which are providing several advantages over monometallic nanoparticles (mono-NPs). As a result of these properties, composite MeNPs, particularly bimetallic nanoparticles (BNPs), have sought the attention of sensor engineers and since then there has been rapid rise in the number of reports of sensors incorporating BNPs within a brief period of time. Keeping this pivotal fact in consideration, we have complied this review to give readers a clear insight in the possible ways BNPs can be synthesized that would render them to possess crucial characteristics desired for bio/chemical sensor fabrication and their applications. We have also discussed different characterization techniques that have been applied to investigate various properties of the BNPs along with a table that gives information on how each technique is different and in what ways they complement each other. Moreover, a comprehensive report on the incorporation of different BNPs in sensor fabrication for detection of hydrogen peroxide (H2O2), glucose, pesticides, nucleic acids, proteins, cancerous and bacterial cells has been described. The comparison of analytical performance of the biosensor design incorporating mono-NPs and BNPs, in terms of linear range (LR), limit of detection (LOD), sensitivity, and specificity, has also been discussed to show the importance of BNPs in sensing matrix.

Biomedical Potential of Marine Sponges

Marine sponges, ubiquitously occurring invertebrates, are sources of diverse variety and unique metabolites that indicate their potential in therapeutics and biomedical science. They are the richest sources of pharmacologically active compounds from marine organisms. These bioactive compounds have the potential to become future drugs against important diseases such as cancer and malaria. They also have a range of biomedical applications but are yet to be commercialized to leverage the benefits for the society. In this chapter compounds or metabolites that had been isolated from marine sponges have been defined, followed by a brief account of their characteristics and numerous activities that may have potent impact on biomedical applications as they may emerge out as convincing solutions for numerous significant diseases. The products obtained show antiviral, antimicrobial, and antiprotozoal activity. These compounds can also be used as immuno- and neurosuppressors and can be implemented to an array of medical diagnostics.