Regardless of the introduction of broad-spectrum antibiotics, pathogenic bacteria are still the main cause of life-threatening infectious diseases in the world. Prompt detection of pathogens with the lowest concentrations (<100 cfu/mL) without time-consuming procedures, such as culture or amplification by PCR is very important in disease diagnosis and the subsequent treatment regimen.
Introduction
With the advent of nanomedicine in recent decades numerous nanomaterials have been used for the formulation and synthesis of nanoparticles. A nanoparticle is defined as a tiny particle with a size ranging 1-100 nm. Among the different types of nanomaterials, magnetic gold nanoparticles (GNPs) have attracted much attention in the last decades. The two physical and chemical fundamental properties of GNPs are affected by their nanostructure – shape and crystal texture – which allows them to have numerous biomedical applications in prophylaxis, diagnosis and treatment.
Magnetic Nanoparticles (MNPs) are particles of nanosized range (10−9 nm)(usually ,100 nm in size) with unique properties of magnetic targeting, biocompatibility, surface modification characteristics and superparamagnetic properties. The application of magnetism in medical science was first introduced in the 1950s for “magnetic hyperthermia therapy” (cancer cell death) leading to various MNPs’ syntheses including Superparamagnetic iron oxide NPs (SPIONs).
A fusion protein is a protein composed of several domains (parts) that are encoded by separate genes and have been joined so that they are transcribed and translated as a single unit, producing a single polypeptide maintaining functional properties of each original protein. Fusion proteins can be created “in vivo” and “in vitro” by using recombinant DNA techniques for use in biological research or therapeutics. Fusion proteins occur naturally and commonly in cancer cells, where they may function as oncoproteins having different functions or physico-chemical patterns.
In vitro diagnostics (IVD) are diagnostic tests performed on biological samples (e.g. blood, tissue) obtained from the body to detect DNA/RNA, microorganisms, or biological biomolecules (e.g. protein) associated with diseases, infections or medical conditions. The IVD tests are generally non-invasive, used both in professional healthcare settings and at home as rapid kits and are useful for early detection of diseases, prevent the spread of diseases and improve patient care and management.
The sandwich ELISA is one of the Enzyme-linked immunosorbent Assay (ELISA) methods which are analytical techniques for the detection of various compounds/analytes in a sample in the biomedical and research setting.
Isolation and identification of cell(s) is the prerequisite step for many fields of research, such as cell function and analysis, signaling and gene expression. Techniques that enable the rapid and accurate enrichment of target cell populations are therefore an area of substantial interest. The output of cell-sorting techniques from the cell suspension is based on higher efficacy or throughput, purity, and recovery. Based on the different principles used, the Cell sorting techniques are categorized into two general categories:
Immunoassay techniques are methods for the sensitive and specific quantitative detection of chemical substances such as hormones, drugs and specific proteins that utilize the highly specific binding between an antigen or hapten and homologous antibodies.
While chemiluminescence and fluorescence are used interchangeably, especially when referring to tracking strategies for magnetic separation in biosensors or in-vitro diagnostic assays, however, they are different concepts. They both give off a photon as an electron relaxes from a higher energy state to a lower energy state, but the difference lies in the method used to excite that electron to a higher energy state in the first place. In fluorescence the electron is kicked up to a higher energy state by the addition of a photon. In chemiluminescence the electron is in a high-energy state due to the creation of an unstable intermediate in a chemical reaction. Light is released when the intermediate breaks down into the final products of the reaction.
The separation of charged biomolecules of a solution by their size and molecular weight is common for scientific studies and biomedical techniques for which various techniques of “electrophoresis” use an electric field, protein electrophoresis is among the widely used procedures.
