Table 1.

Challenegs and applications of detection technologies.

Detection method	Challenges.	Application of detection methods to superbugs or the novel coronavirus (SARS-CoV-2)
Biosensor-based method	• Sensitivity to pH, change of mass, and temperature [24] • Difficult for biosensors to apply to real-world environmental samples (e.g., interfering microbial species, particulate matter, and humic substances) [25]	Staphylococcus Bacteria [15]
Fluorescence in situ hybridization (FISH)	• Low sensitivity • Pre-enrichment and concentration steps [17]	Ampicillin-resistant Escherichia coli [16]
Surface-enhanced Raman spectroscopy (SERS)	• Matrix interference and spectra changes during measurement [19] • High cost of the confocal micro-Raman instrument • Need for user-friendly software • Not applicable for field monitoring settings	• Methicillin-resistant S. aureus (MRSA) / • Pseudomonas. aeruginosa [18]
Polymerase chain reaction (PCR) [20]	• Accurate primers and optimal reaction mixture are required to avoid faulty results [17,22].	Novel coronavirus (SARS-CoV-2), with an N_Sarbeco qPCR assay following the electronegative membrane-vortex (ENV) method [21]
Nanofiber filters (application of a nanofiber membrane at a pretreatment process stage)	• High risk of losing functionality of agents (e.g., nanosilver and bronopol) applied for electrospun membranes during leaching [23] • Interference from inhibitors in field samples during nanofiber membrane filtration	Novel coronavirus (SARS-CoV-2) [23]
Factors for development of detection methods • Detecting low concentration of pathogens • Sensitivity, automation, reproducibility, and specificity • Speed (close-to-real-time detection of viruses and bacteria) • Low cost; alleviating interactions among pathogens • Elimination of inhibitors