Harrick Plasma → Applications → Device Fabrication →
Bacteria sensors play a crucial role in reducing food spoilage, minimizing economic losses and illness from foodborne diseases. These sensors can detect spoilage earlier, eliminating its potential to spread throughout the supply chain, from agriculture and packaging steps to transportation and retail. Testing for bacteria ensures safe and fresh products reach consumers, significantly improving food safety and quality control.
Plasma treatment facilitates the development of bacteria sensors by enabling microfluidic device fabrication and immobilizing biomolecules. Plasma cleans and activates material surfaces with reactive functional groups essential for PDMS bonding. These reactive groups can also be used to immobilize biomolecules necessary for biosensor functionality.
Food Packaging Bacteria Sensors
Incorporating bacteria sensors into food packaging may lead to earlier and more efficient detection of food spoilage. Chemically inert materials are often selected for packaging to prevent chemical reactions that can damage their contents. While beneficial for food packaging, this quality presents a challenge for immobilizing biomolecules necessary for bacteria detection. To overcome this challenge, plasma treatment can be used to introduce reactive functional groups to inert material surfaces to bind these biomolecules.
For example, Chen et al treated electrospun polymers with plasma to immobilize reporter phages for use as a bacteria sensor. Chen chose poly-3-hydroxybutyrate (PHB) as their packaging material for several desirable qualities, such as its chemically inert profile. PHB, however, is unable to bind reporter phages without surface chemistry modification. By incorporating plasma treatment in their process, Chen was able to bind these reporter phages in high densities and improved the quality and sensitivity of their bacteria sensor.
Food Packaging Bacteria Sensors Articles
Chen SY, Harrison M, Ng EK, Sauvageau D, Elias AL. “Immobilized Reporter Phage on Electrospun Polymer Fibers for Improved Capture and Detection of Escherichia coli O157:H7”. ACS Food Science & Technology (2021) 1(6):1085-1094 10.1021/acsfoodscitech.1c00101
Microfluidic Bacteria Sensors
Microfluidic devices are inexpensive and portable, offering food scientists the opportunity to rapidly detect dangerous bacteria such as Salmonella typhimurium, Campylobacter, and Escherichia coli in the field. These devices typically employ surface bound antibodies to specifically bind their targeted bacteria prior to detection.
An example of this is the Salmonella typhimurium microfluidic biosensor created by Wang et al. To make the targeted bacteria fluorescent, two complexes were reacted: magnetic nanoparticles (MNPs) and fluorescent microspheres (FMSs) modified with Salmonella typhimurium monoclonal antibodies (MAbs) and polyclonal antibodies (PAbs), respectively. After separating out any unreacted complexes, a concentrated solution was pumped into the microfluidic device and a fluorescent light source was used to calculate the number of bacteria present.
Microfluidic devices are commonly used for these lab-on-a-chip technologies because the biosensors are portable and allow for quick detection. Harrick Plasma Cleaners activate the surface of polydimethylsiloxane (PDMS) and allow it to form a strong bond with glass substrates to fabricate these microfluidic bacteria sensors.
Microfluidic Bacteria Sensors Articles
Cai G, Zheng L, Liao M, Li Y, Wang M, Liu N and Lin J. “A Microfluidic Immunosensor for Visual Detection of Foodborne Bacteria using Immunomagnetic Separation, Enzymatic Catalysis and Distance Indication”. Microchimica Acta (2019) 186(12) 10.1007/s00604-019-3883-x
Hao L, Xue L, Huang F, Cai G, Qi W, Zhang M, Han Q, Wang Z and Lin J. “A Microfluidic Biosensor Based on Magnetic Nanoparticle Separation, Quantum Dots Labeling and MnO2 Nanoflower Amplification for Rapid and Sensitive Detection of Salmonella Typhimurium”. Micromachines (2020) 11(3):281 10.3390/mi11030281
Ma L, Petersen M, Lu X. “Identification and Antimicrobial Susceptibility Testing of Campylobacter Using a Microfluidic Lab-on-a-Chip Device”. Applied and Environmental Microbiology (2020) 86(9):e00096-20 10.1128/AEM.00096-20
Wang S, Zheng L, Cai G, Liu N, Liao M, Li Yanbin, Zhang X and Lin J. “A Microfluidic Biosensor for Online and Sensitive Detection of Salmonella typhimurium using Fluorescence Labeling and Smartphone Video Processing”. Biosensors and Bioelectronics (2019) 140:111333 10.1016/j.bios.2019.111333
Zheng L, Cai G, Qi W, Wang S, Wang M, Lin J. “Optical Biosensor for Rapid Detection of Salmonella typhimurium Based on Porous Gold@Platinum Nanocatalysts and a 3D Fluidic Chip”. ACS Sensors (2019) 5(1):65-72 10.1021/acssensors.9b01472