3.5. Marine nanoparticles-based biosensors:
Marine Nanomaterial based biosensors should be integrated within tiny biochips, which enhances functionality of biosensors as well as made portable, pocket friendly and easy to use (Singh et al., 2015).
Elgamouz et al. (2020) have prepared Noctiluca scintillans ‐mediated AgNP’s biosensor for sensing hydrogen peroxide. It was discovered that the breakdown of hydrogen peroxide on AgNP’s catalytic surface is pH, temperature, and time-dependent. Using Abs calibration curves, the test assay correctly predicts repeatable levels of H2O2 in unlabeled samples in three distinct ranges— mM, M, and nM.
Algal synthesized gold nanoparticles are utilized in the biosensing of cancer diagnostics by analyzing the type and quantity of hormones in the human body. The algae-produced nano Au‐Ag alloy has substantial electrical catalytic activity against 2-butanones and offers a platform for the early phase cancer development in which the biosensor detects the initial stages by recognizing the presence of malignant cells.
In separate research, the AuNPs biosensor from Hypnea Valenciawas shown to be capable of detecting human chorionic gonadotrophin (HCG) in urine samples from pregnant women in an HCG blood pregnancy kit (Kuppusamy et al., 2014). Platinum NPs from S. myriocystum can be used as biosensors to track the amount of adrenaline in the body, which is a hormone-based medicine used to treat allergies, asthma, and heart attacks (Sharma et al., 2019).
3.6. Marine pigment-based biosensors :
A whole-cell biosensor for cadmium assessment utilizing a colorimetric technique has been created using a genetically engineered red pigment generating bacterium Deinococcus radiodurans (Joe et al., 2012). Lac Z reporter gene cassettes were created by combining the promoter regions of inducible genes that detect high levels of Cd. The reporter cassettes were transplanted into D. radiodurans R1 to assess promoter activity and specificity. It can detect cadmium in concentrations ranging from 1mM to 10mM. LacZ expression was increased up to 100 lM Cd, but it swiftly decreased with increasing concentrations. The presence of Cd reforms the color of the sensor bacterium strain (KDH081) from light yellow to red, but the addition of other metals have no impact. With a Cd detection range of 50nM to 1mM, the color shift is produced by the formation of red pigment and can be observed with the naked eye. By introducing a promoter region that may be utilized as a possible colorimetric system-based biosensor, there is a good chance of developing a novel pigment-based vector and host system.
Table 2: List of marine biomaterial-based biosensors