Inkjet printing virus-based sensors

Bacteriophages are viruses that infect bacteria. They are highly specific for bacteria; moreover, one phage can only infect a subgroup of strains within the same bacterial species. Therefore, bacteriophage attached to a surface offers a promising method to detect specific bacterial pathogens in an air or water environment. We envision a pattern of such phage-sensing spots or lines printed onto a surface to provide sensitivity to multiple organisms and multi-sensor reliability. To realize such an application several key technical challenges must first be overcome. The phage must be attached or printed on a surface such that it remains able to interact with and infect the bacteria. After infection there must be a system for growing the bacteria and amplifying the phage without losing the integrity of the pattern. This article discusses the potential of inkjet printed viruses as sensors for bacterial detection and shows our initial efforts in exploring the immobilization of M 13 as a model virus on various substrates via inkjet printing and examining the infectivity of viruses to E. coli cells after the immobilization. Virus lines are inkjet printed on glass, textiles and gels with immobilization via chemical bonding or a soft polymer overlayer. Agrose top overlay assays were preformed to evaluate the infectivity of immobilized M 13 viruses.