User Guide: DuoSpray Ion Source for TripleTOF Systems Operator Guide

Source Parameters and Voltages

Parameter Descriptions

Table B-3 Source-Dependent Parameters

Parameter

Ion Source Gas 1

(GS1)

Ion Source Gas 2

(GS2)

Curtain Gas (CUR)

Temperature (TEM)

Description

Controls the nebulizer gas for the TurboIonSpray

®

Operation—Ion Source on page 39

.

probe. Refer to

Principles of

TurboIonSpray probe: Controls the heater gas. The best sensitivity is achieved when the combination of temperature (TEM) and heater gas (GS2) flow rate causes the LC solvent to reach a point at which it is nearly all vaporized. To optimize GS2, increase the flow to obtain the best signal or signal-to-noise ratio. If you see a significant increase in background noise, reduce the value. Too high a gas flow can produce a noisy or unstable signal.

APCI probe: Controls the nebulizer gas.

Refer to

Principles of Operation—Ion Source on page 39

.

Controls the flow of gas to the Curtain Gas

TM

interface. The Curtain Gas interface is located between the curtain plate and the orifice. It prevents ambient air and solvent droplets from entering and contaminating the ion optics, while permitting direction of sample ions into the vacuum chamber by the electrical fields generated between the vacuum interface and the spray needle. Contamination of the ion entrance optics thus reduces Q0 transmission, stability, and sensitivity, and increases background noise.

Maintain the Curtain Gas flow as high as possible without losing sensitivity.

Controls the heat applied to the sample to vaporize it. The optimal temperature is the lowest temperature at which the sample is vaporized completely.

Temperature is applied to both probes simultaneously.

Optimize in increments of 50°C.

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Operator Guide

RUO-IDV-05-0783-A

Source Parameters and Voltages

Table B-3 Source-Dependent Parameters (continued)

Parameter

Temperature (TEM) -

TurboIonSpray probe

Temperature (TEM) -

APCI probe

Description

Controls the temperature of the heater gas in the TurboIonSpray probe.

The best sensitivity is achieved when the combination of temperature (TEM) and heater gas (GS2) flow rate causes the LC solvent to reach a point at which it is nearly all vaporized.

As the organic content of the solvent increases, the optimal probe temperature should decrease. With solvents consisting of 100% methanol or acetonitrile, the probe performance may optimize as low as 300°C. Aqueous solvents consisting of 100% water at flows of approximately 1000 µL/min require a maximum probe temperature of 750°C.

If the temperature is set too low, then vaporization is incomplete and large, visible droplets are expelled into the ion source housing.

If the temperature is set too high, solvent may vaporize prematurely at the TurboIonSpray probe tip, especially if the probe is set too low (5 mm to 13 mm).

Controls the temperature of the APCI probe.

As the organic content of the solvent increases, the optimal probe temperature should decrease. With solvents consisting of 100% methanol or acetonitrile the probe performance may optimize at temperatures as low as 400°C at flow rates of 1000 µL/min.

Aqueous solvents consisting of 100% water set at flows of approximately 2000 µL/min require a minimum probe temperature of 700°C.

If the temperature is set too low, then vaporization is incomplete and large, visible droplets are expelled into the ion source housing.

If the temperature is set too high, thermal degradation of the sample occurs.

Operator Guide

RUO-IDV-05-0783-A

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