Piezoelectric inkjet

DNA arrays are fabricated by immobilizing the complementary DNA (cDNA) onto a solid substrate such as silicon, nylon or glass. This can be achieved by robotic printing of polymerase chain reaction (PCR) products (also known as direct-deposition approach), photolithographical synthesis of complementary oligonucleotides or piezoelectric inkjet printing of PCR products (also known as indirect-deposition approach). 

Piezoelectric inkjet is currently the technology of choice for most emerging industrial applications. In this technology, a piezo crystal (commonly lead zirconium titanate) undergoes distortion when an electric field is applied, and this distortion is used to mechanically create a pressure pulse that causes a drop to be ejected from the nozzle (Fig. 3). There are many variations of piezo inkjet architectures including tube, edge, face, moving wall, and piston. 

Clay K, Gardner I, Bresler E, Seal M, Speakman S. (2004) Direct legend printing (DLP) on printed circuit boards using piezoelectric inkjet technology. Circuit World 28 24-31. 

Wu HC, Lin HJ, Kuo YC, Hwang WS. (2004) Simulation of droplet ejection for a piezoelectric inkjet printing device. Mater Transact 45 893-899. 

Conversely, in a piezoelectric inkjet (PIJ) head, the deflection of a membrane drives ink through each nozzle — schematics of the various configurations used in PIJ heads can be found elsewhere. The timescale for PIJ drop ejection is similar to that in a TIJ head (Fig. 1), thus, both are capable of firing 10000 to 30000 drops from a nozzle each second. Typical nozzle diameters d = 10—50 fxm), ink viscosities ( 7 = 1—5 centipoise), ink surface tensions (a = 20—50dyne/cm), and ink densities (p = 0.9—l.lg/ml) are fairly similar for the TIJ and PIJ printers for office and home use. The resulting key fluidic parameters for such print heads are summarized in Table 2. 

Derived from standard desktop printers, drop-on-demand techniques, such as electrohydrodynamic jet (e-jet) printing, solid freeform fabrication (SFF), or piezoelectric inkjet printing, are among a few notable examples of rapid prototyping techniques that have been developed to pattern biomaterials. With the incorporation of a user friendly computer interface, these techniques have been employed to process a number of multiplexed, biomaterial constructs without the use of masks, stamps, or any other time consuming processing equipment. The design of such constructs with minimal feature sizes in the microliter to picoliter resolution has been demonstrated and will be discussed below. 

Sumerel JL, Lews J, Doraiswamy A, Deravi LF, Sewell SL, Gerdon AE, Wright DW, Narayan RJ. (2006) Piezoelectric inkjet processing of materials for medical and biological applications. Biotechnol J1 976-987. 

A compact disc-based microarray system was developed by Kido et and used for immunoassays. They used a piezoelectric inkjet applicator to deposit the proteins onto a polycarbonate disc. Recently, Clair et al. reported the attachment of small molecules to a polycarbonate compact disc (CD) surface via phosphodiester bonds. Molecular interactions between analytes and some of these molecules can be detected with a conventional CD player. ... 

In 1990, a piezoelectric inkjet printing principle was introduced by Epson (5,6,19). However, earlier patents with regard to piezoelectric elements can be found (20) ... 

Phosphor particles of 2 jum are uniformly dispersed throughout the composition. The composition is deposited through either thermal or piezoelectric inkjet printing. 

Metal porphyrins and phthalocyanines embedded in transparent sol-gel films have been deposited by piezoelectric inkjet printing. Their use as gas sensors was studied (29). 

FIGURE 19.69 Squeeze tube piezoelectric inkjet. Early implementation of piezoelectric transducers for drop ejection. (Source Advanced Technology Resources Corporation.)... 

Kim JD, Choi JS, Kim BS, Choi YC, Cho YW. Piezoelectric inkjet printing of polymers stem cell patterning on polymer substrates. Polymer 2010 51 2147-2154. 

Piezoelectric inkjet Piezoelectric drop-on-demand Droplet generator Piezoelectric micro/nanoUter droplet dispenser... 

Figure A A Inkjet printing ejection mechanisms (a) Thermal inkjet printing (Reprintedfrom Bcdlarinet at, 2004, with permission from Elsevier), (h) piezoelectric inkjet printing (Fuller et al., 2002) (c) electrostatic inkjet printing (Lin and Bai, 2004) (d) acoustic inkjet printing (Parashkov et al., 2005).

Wang, T., Cook, C., Derby, B., 2009. Fabrication of a glucose biosensor by piezoelectric inkjet printing. In Sensor Technologies and Apphcations, 2009. SENSORCOMM 09. Third International Conference on, 18-23 June 2009, pp. 82-85. 

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