Bacteriophages are the most abundant biological entities in any habitat, reaching an overall abundance of 1031 virus particles. The use of phage as an alternative antimicrobial agent to combat pathogenic bacteria and their association with the healthy gut microbiome has prompted the need for precise methods to detect and count phage particles. There are many applicable methods, but pay attention to the measurement object (infectious phage, phage whole particle, or nucleic acid and protein) and the concept behind the technology to avoid misunderstandings. Although molecular methods cannot distinguish between live phages and non-infectious phages, traditional techniques for counting infectious phages can be very time-consuming and poorly reproducible. At Creative Biolabs, our experienced phage experts use different methods for phage detection and counting to meet customer needs and save cost and time.
Creative Biolabs has the technical expertise, GLP quality system, compliance experience, fast turnaround time, and excellent customer service to ensure the success of your project. Our services are listed as follows, but are not limited to:
| Method | Basis of detection/enumeration | Duration | Manual labor | Advantages | Limitations |
| Double agar overlay assay (DLA) | Virulent phage particles | 1 - 2 days | High | Simple, effective, “gold standard,” shows active virulence | Slow, laborious, high standardization needed for precise reproducibility |
| Transmission electron microscopy (TEM) | Magnification of virus particles | 2 - 3 days | High | Works well with unknown phages | Costly, laborious, high concentration needed |
| Flow cytometry | Viral particles | 4 - 12 h | Moderate | Can detect different phages in a sample | Expensive, low sensitivity, skilled operator needed |
| NanoSight | Nanoparticle detection by laser-illuminated optical microscopy | 5 - 10 min | Low | Rapid runtime | Can be used only on clear, concentrated samples |
| qPCR/RT-qPCR | Viral nucleic acid | 2 - 6 h | Moderate | Precise, reproducible | Overestimation of virulent particles (one magnitude) |
| Droplet digital PCR (ddPCR) | Viral nucleic acid | 2 - 6 h | Moderate | No need for internal standards | Could easily overestimate viral abundance |
| Mass spectrometry | Viral protein | 2 - 3 days | High | Accurate in determining PFU | Time-consuming, surface protein mutants can give false results |
| Illumina sequencing | Viral nucleic acid library | 3 - 4 days | Moderate | Not well suited for quantification | Significant amount of bioinformatics analysis needed |
| PacBio sequencing | Viral nucleic acid | 2 - 5 days | Moderate | Prone to sequencing errors | Long read lengths |
| NanoPore sequencing | Viral nucleic acid (can be amplified if needed) | 8 - 24 h | Moderate | Compact, rapid, multiple use | Expensive, high rate of sequencing read error |
Creative Biolabs can meet the needs of customers for providing phage enumeration and detection services on time and on budget. Our skilled and dedicated scientific researchers ensure that the most suitable methods and techniques are selected for each professional for your project. If necessary, please feel free to contact us.
Please kindly note that our services can only be used to support research purposes (Not for clinical use).
Creative Biolabs is a globally recognized phage company. Creative Biolabs is committed to providing researchers with the most reliable service and the most competitive price.
