The catalytic activity of the enzymes can be introduced to textile surfaces for bio-sensing applications by immobilizing them through a resource-efficient deposition method such as inkjet printing [1]. Contrary to conventional dispensing methods, drop-on-demand inkjet printing can provide with high precision deposition of these enzymes along with flexibility for small-scale production [2]. To the best of our knowledge, studies on the inkjetting of enzymes are limited and often uses a modified/adapted commercial paper printer for jetting [3]. Additionally, the effect of ink formulation and printing condition variables on the activity of enzyme are not well explored. Many of such variables suggested for jetting of proteins [4] includes e.g. ink rheology, operating temperature, drop size retention, and the shear force acting on the ink. In our research effect of these variables are studied using a digital inkjet printer (Xennia Carnelian) with a Sapphire QS10 piezo-electric print head (Fujifilm Dimatix, USA). Lysozyme is used as a model enzyme for printing due to its well-known structure and catalytic mechanism. Effect of temperature and shear force development within the print head on lysozyme activity is investigated. Additionally, pre-treatment of the fabric to improve ink adhesion through various surface activation processes are studied. Finally, remaining activity of the printed enzymes over washing is evaluated to ensure the fastness property.

Acknowledgment

This research project is funded by University of Borås, Sweden.

References

[1]     Li J, Rossignol F, Macdonald J. Inkjet printing for biosensor fabrication: combining chemistry and technology for advanced manufacturing. Lab on a Chip 2015;15(12):2538-2558.

[2]     Nierstrasz V, Yu J, Seipel S. Towards more flexible, sustainable and energy-efficient textile functionalization processes: Digital inkjet in functional and smart textile production. In: 9th Aachen-Dresden International Textile Conference 2015; 2015.

[3]     Yamazoe H. Fabrication of protein micropatterns using a functional substrate with convertible protein-adsorption surface properties. J Biomed Mater Res A 2012;100(2):362-9.

[4]     Delaney JT, Smith PJ, Schubert US. Inkjet printing of proteins. Soft Matter 2009;5(24):4866-4877.