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Companies making medical products often coat them with drugs (stents) , anti-coagulating chemicals (blood collection glassware), bactericides (wound dressings and sutures), and a host of other materials. One method of creating and applying the coating is through ultrasonic atomization and deposition using MicroMist spray nozzles from Sono Tek Corp, Milton, NY.

In the process, the liquefied coating is delivered to the nozzle's atomizing surface via an external hypotube. Low -pressure air (up to 2 psi) going through the nozzle entrains the liquid and generates a precise spray pattern of 0.01 to 0.03 in. in diameter. The flow rate can be adjusted from 0.3 to 9 ml/hr. And because the air pressure used is so low, overspray and waste are reduced and the spray and its shape can be more closely controlled. The nozzle is self-cleaning, which prevents clogging.