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. 2018 Jul-Sep;8(3):170-174.
doi: 10.4103/jmss.JMSS_41_17.

Bacterial Bioprinting on a Flexible Substrate for Fabrication of a Colorimetric Temperature Indicator by Using a Commercial Inkjet Printer

Zeinab Mohammadi  1 , Mohsen Rabbani  1
Affiliations

Bacterial Bioprinting on a Flexible Substrate for Fabrication of a Colorimetric Temperature Indicator by Using a Commercial Inkjet Printer

Zeinab Mohammadi et al. J Med Signals Sens. 2018 Jul-Sep.

Abstract

Background: Bacterial sensors are recommended for medical sciences, pharmaceutical industries, food industries, and environmental monitoring due to low cost, high sensitivity, and appropriate response time. There are some advantages of using bacterial spores instead of bacteria in vegetative forms as spores remain alive without any nutrient for a long time and change to vegetative form when a suitable environment is provided for them.

Methods: For biosensor fabrication, it is important to define how the bacterial spores are delivered to the substrate media. The main purpose of this paper is an investigation of transferring bacterial spores on a flexible substrate media using a commercial inkjet printer (HP Deskjet 1510). It should be noted that in the previous researches, the special printers were used to transfer bacteria on rigid films.

Results: These printed bacterial spores are used as a colorimetric temperature indicator. The custom-made bio-inks are prepared by bacterial spores along with a gelling agent and pH indicator.

Conclusions: Finally, transformation of bacterial spores into vegetative bacteria is occurred by changing of temperature. A color change in the bio-prints is demonstrated because the bacterial transformation and growth change the environmental pH to an acidic level.

Keywords: Bacterial spores; biosensor; colorimetric indicator; flexible substrate; printer.

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Conflict of interest statement

There are no conflicts of interest.

Figures

Figure 1
Figure 1
(a) Empty black cartridge after absorber sponge removal. (b) Empty tri-color cartridge with 3 chambers
Figure 2
Figure 2
(a) Amounts of each solution determined by percentages of CMYK; Cyan: Guar gum 0.2%, Magenta: Borax 1%, Yellow: TSB, Black (K): Bacterial spores. (b) Adjust the print resolution to 200 PPI for printing circles on the substrate. (c) Schematic of two-step methods; PPI: Points per inch
Figure 3
Figure 3
(a) Printed spores of geobacillus stearothermophilus and samples that covered with guar gum solution. (b) Printed spores of Bacillus atrophaeus and samples that covered with green gel. (c) Printed Bacillus atrophaeus on a flexible substrate after incubation in a suitable environment demonstrate a color change from green to yellow. (d) Light micrograph of a malachite green–stained smear of Bacillus atrophaeus cells showing greenish-blue spores. (e) Growth of printed geobacillus stearothermophilus is demonstrated by staining with Safranin e showing reddish vegetative bacteria
Figure 4
Figure 4
Images of Bacillus atrophaeus printed on the polymeric substrate; (a) 100% borax (4×) (b) 0% borax (4×), (c) 100% borax (40×) (d) 0% borax (40×)
Figure 5
Figure 5
Images of coated Bacillus atrophaeus that printed on the polymeric substrate; (a) 100% borax (4×) (b) 0% borax (4×), (c) 100% borax (40×) (d) 0% borax (40×)
Figure 6
Figure 6
Images of printed geobacillus stearothermophilus on the polymeric substrate with 4×, and 40× magnifications; (a) 100% borax (4×) (b) 0% borax (4×), (c) 100% borax (40×) (d) 0% borax (40×)
See this image and copyright information in PMC

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References

    1. Aikio S, Grnqvist S, Hakola L, Hurme E. Bioactive Paper and Fibre Products VTT Technical Research Centre of Finland. 2006:83.
    1. Lukacs G, Maloney N, Hegner M. Ink-jet printing: Perfect tool for cantilever array sensor preparation for microbial growth detection. J Sens 2012. 2012:7.
    1. Cho MO, Yoon S, Kim JK. Inkjet Printing of High-Density Bacterial Arrays for Biosensor Applications. In: ASME 2010 First Global Congress on Nano Engineering for Medicine and Biology. American Society of Mechanical Engineers. 2010
    1. Srimongkon T, Mandai S, Enomae T. Application of biomaterials and inkjet printing to develop bacterial culture system. Adv Mater Sci Eng 2015. 2015:9.
    1. Kuswandi B, Wicaksono Y, Jayus, Abdullah A, Heng LY, Ahmad M, et al. Smart packaging: Sensors for monitoring of food quality and safety. Sens Instrum Food Qual Saf. 2011;5:137–46.