Piranha Solution

Contents

1. Overview
2. Piranha single slide clean

1. Overview

2 volumes of Sulfuric Acid for each volume of Hydrogen Peroxide.

To clean one wafer I use 400ml of Hydrogen Peroxide with 800 ml of Sulfuric Acid. To clean all the wafers I use 500 ml of Hydrogen Peroxide and 1000 ml of Sulfuric Acid.

This big volumes of piranha are only mixed in Acid hood in MER clean room. Clean room has all chemicals and materials needed for this.

2. Piranha single slide clean

This protocol is used for cleaning the pattern surfaces of flow cells after sufficient use (4 uses).

Danger

Piranha is dangerous! Please be careful not to let any organics NEAR it! This is especially true for EtOH

2.1 Materials Needed

• Pre-Cleaned slides to be washed
• Sulfuric Acid
• 30% Hydrogen Peroxide
• Glass Narrow Beaker or slide holder
• Larger beaker that can hold the narrow beaker
• Tweezers (Teflon is Best)

2.2 Protocol

1. In the acid hood, place the smaller beaker in the larger beaker.
2. Use a graduated cylinder to measure and add 10ml hydrogen peroxide.
3. Use a separate graduated cylinder to add 30ml of sulfuric acid to the small beaker.
4. Let the piranha stand and react for 5 minutes.
5. Place a single slide into the small beaker on its end so that a small edge is still exposed. Let the slide clean for one minute.
6. After cleaning, wash the slide in water. Leave all slides in the water until piranha for all samples is done.
7. When piranha cleaning is done, transfer the used piranha to a bottle and set aside.
8. Transfer the slides from water to ethanol. After 15 minutes or longer dry the slide and put into the vacuum oven overnight.
9. At the end of the day, screw a cap loosely over the piranha.