Thermo Scientific Surveyor UV Plus, Руководство по оборудованию

Страница: 52 / 76

3
Maintenance
Cleaning the Flow Cells
36 Surveyor UV/Vis Plus Detector Hardware Manual Thermo Scientific
Cleaning the Flow Cell with Organic Solvents
If you suspect that the flow cell needs to be cleaned, try using organic solvents to clean it.
 To clean the flow cell with an organic solvent
1. Remove the column from the chromatographic system to avoid column degradation.
2. Connect the flow cell inlet directly to the chromatographic pump outlet.
3. If necessary, flush the flow cell with water to prevent a reaction between the last solvent
used in the chromatographic system and the cleaning solvent that you will use to clean
the flow cell.
4. Flush the flow cell with 40 to 50 mL of cleaning solvent, for example, isopropanol or
methanol.
5. Flush the flow cell with water to prevent a reaction between the cleaning solvent and the
mobile phase that is used in your chromatographic application.
Cleaning the Flow Cell with Nitric Acid
Methanol or isopropanol is generally sufficient for cleaning a flow cell. However, if the flow
cell remains contaminated after flushing it with organic solvents, remove the flow cell from
the detector and clean it with nitric acid.
IMPORTANT Ensure that the cleaning solvents you plan to use are miscible with
the solvent already present in the flow cell and pump. Isopropanol is a good cleaning
solvent for most applications. If the last solvent in the pump was an aqueous buffer
solution, be sure to pump 25 to 40 mL of HPLC-grade water (or its equivalent)
through the system to remove any salts before you flush the pump with the cleaning
solvents.
CAUTION Do not use a syringe to force solvent through the flow cell. Pressurizing
the flow cell can cause a leak or rupture and result in a dangerous and uncontrolled
spraying of solvent.
CAUTION Nitric acid is a strong oxidizing acid, and it can react vigorously with alcohols
(especially methanol). Be sure to wear protective clothing and eye protection and adhere
to your company’s safety procedures for the proper handling and disposal of corrosive
acids. Flush the flow cell with water to remove all traces of alcohol before flushing it with
nitric acid.
CAUTION If cleaning the flow cell does not remove the contamination, replace the flow
cell. Do not attempt to repair the flow cell by disassembling it.