How To Configure the OptiFlow® Turbo V Ion Source with the Microflow Probe for Nanoflow Rates

For research use only. Not for use in diagnostic procedures.

Answer

Nanoflow rates can be achieved using a microflow probe with an OptiFlow® Turbo V ion source on the ZenoTOF 7600 system. The OptiFlow Turbo V ion source is a dual-flow ion source designed for either microliter-per-minute flow rates (microflow 1-10, 10-50, or 50-200 μL/min) or nanoflow rates (≤ 1 μL/min). When the OptiFlow Turbo V ion source is configured for microflow rates, the calibrant delivery system (CDS) probe is attached to the source where the nanoflow probe is normally attached (see image below). This enables automated calibration during sample acquisition.

On the other hand, when the OptiFlow Turbo V ion source is configured for nanoflow, the nanoflow probe must displace the CDS probe from the from the front of the ion source, necessitating the use of on-column calibrant delivery. The on-column system calibration is very time-consuming, and even if the gradient is shortened, it takes easily 30 to 45 min to complete a simple gradient at 300 nL/min. This lengthy calibration can be drastically reduced if nanoflow users switch to CDS calibration delivery directly through the OptiFlow Turbo V ion source by setting up their nanoflow columns and microflow probe as described below.


These images (below) show the nanoflow column attached to the microflow probe at the top of the OptiFlow Turbo V ion source assembly. The nanoflow column (such as the Waters HSS T3 column) needs to have a distal fused silica ending (left) or a 1/16” fitting (right). In both cases, the CDS probe remains connected horizontally to the ion source assembly, as it is during microflow analysis.


Some examples of alternative nanoflow column outlet connections to the microflow probe on the OptiFlow Turbo V ion source are provided below:
(1) 1/32” PEEK nut with a tan sleeve for 360 OD fused silica and a VALCO 1/16”-to-1/32” reducing union (0.15 mm bore)
(2) High-pressure union body for NanoTight sleeves or 1/16" OD tubing, PEEK, 0.005" ID 10-32 (coned) and a 1/16” VICI nut
(3) a MicroTight nut (360 OD, 6-32 thread) with a green PEEK sleeve (0.0155” ID x 0.05” OD) and a PEEK ZDV MicroTight adapter



More details about this setup and its part numbers can be found in this technical note: A simplified orthogonal electrospray source setup for robust nanoflow or microflow proteomics analysis.