Printed biotin-functionalised polythiophene films as biorecognition layers in the development of paper-based biosensors

Flexible Sensors—From Materials to Applications

“…Nevertheless, these techniques require specialised equipment and are not easily scaled up to large area fabrication. Solution based processes such as spin coating [193], spray coating [337], electrospinning [147], roll-to-roll printing [338], inkjet printing [137,339,340], dispenser printing [341], and screen printing [337,342], offer an easier approach for the deposition of films on large area flexible substrates. In addition, these techniques are mostly applied at low temperatures, making them compatible with substrates that require a low thermal budget.…”

“…Thiophene-based organic conductors such as polythiophenes (Tn), tetraethylene-glycol polythiophene (TEGPT) [137], or p-poly(3,4-ethylenedioxythiophene) (PEDOT) [138][139][140][141], have also been adopted for the fabrication of flexible sensors for bio-recognition. TEGPT functionalised with biotin (b-TEGPT) films were reported to be inkjet-printed on paper substrate by Ihalainen et al [137], obtaining a conductivity in the range of 10 × 10 -7 S/cm to 10 × 10 -6 S/cm.…”

“…Thiophene-based organic conductors such as polythiophenes (Tn), tetraethylene-glycol polythiophene (TEGPT) [137], or p-poly(3,4-ethylenedioxythiophene) (PEDOT) [138][139][140][141], have also been adopted for the fabrication of flexible sensors for bio-recognition. TEGPT functionalised with biotin (b-TEGPT) films were reported to be inkjet-printed on paper substrate by Ihalainen et al [137], obtaining a conductivity in the range of 10 × 10 -7 S/cm to 10 × 10 -6 S/cm. However, PEDOT is one of the most prominent polythiophenes with high conductivity and good filming properties that made it broadly used in electric and electronic applications (antistatic coating, electrically conductive coatings, thermoelectric materials, field effect transistors, and active material for electrochemical devices), and is also widely used for flexible sensor applications [138][139][140][141].…”

Organic Bioelectronics: Using Highly Conjugated Polymers to Interface with Biomolecules, Cells, and Tissues in the Human Body

“…While biorecognition elements can be incorporated directly into polymer sidechains, [ 38,101 ] they are challenging to conjugate without overly disrupting the underlying charge transport. [ 102 ] Instead, they are often conjugated either to an intermediate coating or layer, [ 103,104 ] or to metal electrodes that form part of the device.…”

“…Conjugated polymers are not only patternable in 2D, but also via 3D printing methods. [ 36 ] Highly conjugated polymers can be patterned onto flexible plastics, glass, paper, [ 37,38 ] or incorporated directly into composite gel systems. [ 39 ] They can be drawn into fibers, nanofibers, or used to coat existing fibers which can subsequently be woven into organic electronic fabrics.…”