• Progress in nanomaterial-based biosensors for pathogenic bacteria
  • Yeganeh Lalehzari,1 Tayyebe Vaezi,2 Mahsa Alem,3 Abed Ebrahimi,4,*
    1. Department of Medical Immunology, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
    2. Student Research Committee, Tarbiat Modares University of Medical Sciences, Tehran, Iran
    3. Department of Pathobiology, Urmia University, Urmia, Iran
    4. Department of Operating Room, School of Allied Medical Sciences Bushehr University of Medical Sciences , Bushehr, Iran


  • Introduction: Pathogenic bacteria infections cause health threats and financial concerns.Rapid, sensitive, specific and reliable detection of pathogenic bacteria is essential. Conventional methods for detecting bacteria largely such as culturing techniques and biochemical analysis are time-consuming and laborious.PCR and PCR-based methods are unable to distinguish between live and dead bacteria, which could be a potential gap to limit the future development of PCR. Organic/inorganic nanomaterials (polymers, lipids, metal oxides, nanoparticles, etc.) have been widely studied for biological infection problems, because of their flexibility, functional modification, and controllable drug targeting/releasing. The purpose of this review article was to summarize progress in nanomaterial-based biosensors for pathogenic bacteria.
  • Methods: In this review article, we collected the required data using keywords and using databases such as Google Scholar, PubMed, Scopus and ProQuest. In this study, the statistical population includes all the studies whose articles have been published until 2022. After reviewing the findings and evaluating the quality of the obtained data, 13 articles were analyzed.
  • Results: Developed CRISPR-Cas12a-powered dual-mode is able to used as a nanomaterial biosensor consisting of gold nanoparticles (AuNPs) with DNA endonuclease-targeted CRISPR trans reporter. DNA Pom-Pom like nanostructure with a diameter of ~50 nm, and successfully achieved DNA PP-N based multifunctional platform. To utilize this PP-N assembly as an amplifies signal probe and aptamer as bacteria recognition element. Other biosensors include: Aptamer as an oligonucleotide selected by repeated screening in vitro or systematic evolution of ligands by exponential enrichment(SELEX) in aptamer-based biosensors, electrochemical biosensors, Paper-based analytical devices (PADs) emerged as critical POC tools.
  • Conclusion: DNA nanomaterials as biological analysis tools can be attributed to their unique structure and property features: simple and quick producing process; being environment-friendly; good chemical and thermal stability; easy for chemical conjugation and modification. In general, using highly specific Watson-Crick base pairing capability through the formation of hydrogen bonding, several 2D/3D DNA nanostructures of varying size and complexity have been successfully assembled. The aptamer-functionalized and antibiotics-loaded PP-N platform demonstrates excellent merits of high antibiotic’s molecule loading capacity and negligible cytotoxicity to targets. The amplicons of Salmonella (used as a model)-specific invA sequence trigger CRISPR-Cas12a-based indiscriminate degradation of single-stranded DNAs that are supposed to link two gold nanoparticles (AuNP) probe pairs, inducing an aggregation-to-dispersion change, so the advantages of this method can be mentioned that, this generated observable color changes that became even more apparent after centrifugation. The color changes can be discerned by the naked eye and recorded using a portable colorimeter.PADs due to their simplicity, low fabricating costs, easy storage, portability, and disposability, particularly in resource-limited areas, emergencies, and in-home healthcare, without relying on external devices and reagents are important for medical diagnostics and among them, colorimetric paper-based biosensors are in demand and are the most attractive because the presence of a specific pathogen can be conveniently monitored by a simple change in color, which can be distinguished easily with the naked eye without expensive and complex but the major limitation of colorimetric assays is low sensitivity since it is often difficult to transform detectable signals into a color readout. Disadvantages of using viruses and bacteria as a sensing element include poor selectivity, low sensitivity, and slow response, which limits the interest in expanding biosensors to detect pathogens in the market. The future perspective is to develop, smart contact devices consisting of hundreds of biosensors and nanomaterials, for early detection of cancers or other malignancies.
  • Keywords: nanomaterial, biosensor, pathogen detection