How can you recognize injection overload or detector saturation in a chromatogram?

How can you recognize injection overload or detector saturation in a chromatogram?

• A. Increased baseline noise only.
• B. Fronting or tailing changes, broadened peaks, or nonlinearity of the calibration curve at high concentrations.
• C. Decrease in retention time for all peaks.
• D. Emergence of ghost peaks.

Answer: (B)

When the injector or detector is overloaded, the system’s response can no longer rise proportionally with concentration, so peak shapes and the overall signal behavior reveal the saturation. You’ll see distortions in the peaks: fronting indicates the leading edge is compressed, tailing shows the trailing edge is stretched out, and the peaks may broaden instead of staying sharp. At high concentrations, the detector’s dynamic range is pushed, so the calibration curve stops being a straight line and becomes nonlinear. Baseline noise by itself isn’t a specific sign of overload, a uniform drop in retention time across all peaks points to other changing conditions like the mobile phase or column, and ghost peaks are separate artifacts not directly caused by overload.

When the injector or detector is overloaded, the system’s response can no longer rise proportionally with concentration, so peak shapes and the overall signal behavior reveal the saturation. You’ll see distortions in the peaks: fronting indicates the leading edge is compressed, tailing shows the trailing edge is stretched out, and the peaks may broaden instead of staying sharp. At high concentrations, the detector’s dynamic range is pushed, so the calibration curve stops being a straight line and becomes nonlinear. Baseline noise by itself isn’t a specific sign of overload, a uniform drop in retention time across all peaks points to other changing conditions like the mobile phase or column, and ghost peaks are separate artifacts not directly caused by overload.