Establishment and Verification of a SARS CoV2 Antibody Detection Assay Comparing Venous and Mitra Samples

During the COVID-19 pandemic in 2020, the need for highly-specific, wide-spread, and rapid serological testing surged. In this study, we showed very strong positive correlation between venous blood collection and Mitra home sampling kits for the detection of anti- spike IgGs using an in-house ELISA protocol (based on a protocol from Mt. Sinai). This study demonstrates the utility of using at-home, patient-centric testing to enhance the sero-surveillance methods currently in place for viral tracking and monitoring

Biomarkers for Cancer: A Detail Review

When aberrant cells multiply uncontrolled, transcend their normal borders, invade nearby tissues, or spread to other organs, a wide spectrum of illnesses collectively referred to as "cancer" can arise in practically every organ or tissue of the body. The second-leading cause of death globally in 2018, cancer was expected to be responsible for 9.6 million deaths, or one in every six fatalities. A cancer biomarker is a characteristic that can be used to gauge a patient's likelihood of developing cancer or its outcome. Various biomarkers can be used at molecular and cellular level. It is crucial that biomarkers undergo thorough review, including analytical validation, clinical validation, and appraisal of clinical value, prior to being included into normal clinical treatment because of the crucial role they play at all stages of disease. We discuss important steps in the creation of biomarkers in this review, including how to prevent introducing bias and standards to adhere to when presenting the findings of biomarker research

Recent Advances in Enhancement Strategies for Electrochemical ELISA-Based Immunoassays for Cancer Biomarker Detection

Electrochemical enzyme-linked immunosorbent assay (ELISA)-based immunoassays for cancer biomarker detection have recently attracted much interest owing to their higher sensitivity, amplification of signal, ease of handling, potential for automation and combination with miniaturized analytical systems, low cost and comparative simplicity for mass production. Their developments have considerably improved the sensitivity required for detection of low concentrations of cancer biomarkers present in bodily fluids in the early stages of the disease. Recently, various attempts have been made in their development and several methods and processes have been described for their development, amplification strategies and testing. The present review mainly focuses on the development of ELISA-based electrochemical immunosensors that may be utilized for cancer diagnosis, prognosis and therapy monitoring. Various fabrication methods and signal enhancement strategies utilized during the last few years for the development of ELISA-based electrochemical immunosensors are described

Bio-Inspired Materials for Electrochemical Sensors

Electrochemical biosensors are a rapidly growing research area that has greatly improved its specificity, accuracy, and precision in the detection of biomolecules in contemporary literature and industry alike. Typically, these systems exist in a three-electrode conformation with a working electrode functioning as the anode, a counter electrode functioning as the cathode, and a reference electrode allowing for the control of potential in the system. The method by which these sensors work is through the sharing of electrons via redox reactions with the target molecule and the working electrode or modifications on its surface. By exploiting the function of biomaterials that participate in natural substrate-binding redox phenomena, new opportunities for detecting critical molecules in complex situations can be created. In this dissertation, three distinct electrochemical biosensors were created by mimicking natural phenomena and implementing materials that directly or indirectly participate in the corresponding reactions. First, a dopamine sensor was created via a composite of lignin-derived graphene oxide and the marine algae-derived polysaccharide kappa carrageenan. Different ratios of GO, a known electrooxidizing catalyst of dopamine, with kappa carrageenan were used to create a binder-free film for dropcasting on the working electrode. It was designed on the principle of its interactions with the nervous system when injected in rats to induce analgesia, interfering with standard dopamine behavior. The system demonstrated a linear range of 1 - 250 μmol L-1 and a limit of detection of 0.14 μmol L-1 (s/n=3). In the second chapter, a sensor for the human and animal health hazard nitrite was constructed using the transition metal sulfide NiS. Transition metal sulfides are the catalytic center for nitrite oxidation to nitrate in nitrogen fixing bacteria found in the environment. This section utilized a novel electrodeposition method for creating a binderfree layer of NiS on the surface of the glassy carbon electrode. This system demonstrated a linear range of 0.04 – 1 μM, 1 – 5.3 μM and a detection limit of 0.01 μM. For the final chapter, a novel sensor was created for the cryoprotective sugar trehalose, an indicator of bacterial contamination in meat and produce without any electrochemical assay precedent. This system utilized the interactions found between alkali earth metal ions and trehalose in which the two molecules form complexes. Magnesium phthalocyanine, which is a commercially available dye, as well as synthesized magnesium tetraphenylporphyrin and calcium tetraphenylporphyrin were implemented as drop-casted coatings on the working electrode to electrodeposit trehalose on the surface and detect its oxidation via squarewave anodic stripping voltammetry in the complex media Luria-Bertani broth. The system was also used to gauge fluctuations in E. coli in broth by autoclaving the cultures and directly testing the media containing lysed bacteria. The system demonstrated a linear range of 0.25 mM – 100 mM, with magnesium mesotetraphenylporphyrin exhibiting the highest repeatability

Raman spectroscopy based strategies for prevention and early detection of respiratory tract infections in susceptible individuals

Respiratory tract infections (RTIs) are responsible for the significant part of deaths worldwide. At the special danger of lethal outcome are individuals with higher susceptibility to RTIs, this includes people with any type of immunosuppression, individuals suffering from chronic respiratory tract diseases, persons with some genetic disorders affecting the respiratory organs, children till the age of five and elderly generation. Within the framework of this thesis, the potential role of Raman spectroscopic techniques (RST) for improving prevention and diagnostic strategies of RTIs in such susceptible individuals was assessed, highlighting the need of careful choice of the technique according to the desired clinical task. Firstly, using UV-Resonance Raman spectroscopy (UV-RRS) combined with multivariate analysis, the successful identification of fungal spores especially dangerous to susceptible individuals was demonstrated. Next, utilizing mouse model of aspergillosis, conventional Raman spectroscopy of urine was introduced as an easy tool for screening the RTI and its diagnostic performance was compared to that for other diseases. Lastly, the SERS detection of the metabolite of P. aeruginosa bacterium directly in complex matrixes of saliva and artificial sputum using easily prepared SERS substrates was presented