It is our common experience to see water drip out of a leaky faucet in, say, a kitchen sink. While dripping in this case may be an unwanted process, it can gainfully be employed as one of the methods, among a host of different techniques, to produce drops of various liquids for useful purposes. Production of drops, of various sizes and numbers, is used in a variety of applications ranging from crop sprays to printing and patterning on different substrates. In this short write-up, brief descriptions of several different methods available for the production of drops in such applications are included. Mainly, techniques that are used to produce micron sized (in diameter) drops are highlighted and their use in many of the emerging applications such as printing of three-dimensional arrays of biological cells and printing of flexible electronics are discussed.

Schematics showing the production of drops through (a) electrohydrodynamic (EHD) tip streaming and (b) flow-focusing.

The author is a postdoctoral research associate at the School of Chemical Engineering in Purdue University. He holds a Ph.D. degree from Rice University, Houston, Texas, in chemical engineering. At Purdue, the author's research work is supervised by Professor Osman A. Basaran, who is affiliated to the School of Chemical Engineering and is Reilly Professor of Fluid Mechanics there.

Pradeep P. Bhat and Osman A. Basaran
School of Chemical Engineering
Purdue University, West Lafayette, IN 47907

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Researchers should cite this work as follows:

• Pradeep P. Bhat (2008), "Drop formation: Methods and applications," https://pharmahub.org/resources/268.

  BibTex | EndNote

1. Drop formation
2. Drop-on-demand
3. Ink-jet printing
4. Microfabrication
5. Micromanufacturing