Related Experiment Video
Updated: Sep 21, 2025
Foodborne Pathogen Screening Using Magneto-fluorescent Nanosensor: Rapid Detection of E. Coli O157:H7
Published on: September 17, 2017
Molecular detection of bacterial contamination in plasma using magnetic-based enrichment
Jinyeop Lee1,2, Abdurhaman Teyib Abafogi1, Sujin Oh3
1School of Mechanical Engineering, Sungkyunkwan University, Suwon, South Korea.
Abstract:
Bacterial contamination of blood products is a major problem in transfusion medicine, in terms of both morbidity and mortality. Platelets (PLTs) are stored at room temperature (under constant agitation) for more than 5 days, and bacteria can thus grow significantly from a low level to high titers. However, conventional methods like blood culture and lateral flow assay have disadvantages such as long detection time, low sensitivity, and the need for a large volume of blood components. We used real-time polymerase chain reaction (PCR) assays with antibiotic-conjugated magnetic nanobeads (MNBs) to detect enriched Gram-positive and -negative bacteria. The MNBs were coated with polyethylene glycol (PEG) to prevent aggregation by blood components. Over 80% of all bacteria were captured by the MNBs, and the levels of detection were 101 colony forming unit [CFU]/mL and 102 CFU/mL for Gram-positive and -negative bacteria, respectively. The detection time is < 3 h using only small volumes of blood components. Thus, compared to conventional methods, real-time PCR using MNBs allows for rapid detection with high sensitivity using only a small volume of blood components.
Insights
Rapid detection of bacterial contamination in blood products is crucial. This study introduces a real-time PCR assay using magnetic nanobeads for sensitive and fast bacterial identification in platelets.
Area of Science:
- Transfusion Medicine
- Biotechnology
- Microbiology
Background:
- Bacterial contamination of blood products, especially platelets stored at room temperature, poses significant risks of morbidity and mortality.
- Conventional detection methods (blood culture, lateral flow assay) are often slow, lack sensitivity, and require large sample volumes.
- There is a critical need for rapid, sensitive, and efficient methods to ensure blood product safety.
Purpose of the Study:
- To develop and evaluate a novel method for rapid and sensitive detection of bacterial contamination in blood products.
- To improve the safety of transfusion medicine by addressing limitations of current bacterial detection techniques.
Main Methods:
- Utilized real-time polymerase chain reaction (PCR) assays combined with antibiotic-conjugated magnetic nanobeads (MNBs) for bacterial enrichment and detection.
- Coated MNBs with polyethylene glycol (PEG) to prevent aggregation in blood components.
- Tested detection limits for Gram-positive and Gram-negative bacteria.
Main Results:
- Over 80% of bacteria were effectively captured by the MNBs.
- Achieved detection limits of 10^1 CFU/mL for Gram-positive bacteria and 10^2 CFU/mL for Gram-negative bacteria.
- Demonstrated a total detection time of less than 3 hours using small blood volumes.
Conclusions:
- Real-time PCR with antibiotic-conjugated MNBs offers a rapid and highly sensitive method for detecting bacterial contamination in blood products.
- This approach significantly improves upon conventional methods, enhancing the safety and efficiency of transfusion medicine.
- The use of PEG-coated MNBs ensures effective capture without interference from blood components.
