Discharge Ionization Detectors for GC

Discharge-ionization detectors (DID) for GC are specialized detectors that are often used in applications that require high sensitivity and "universal" detection. The DID technology is simple in design but difficult to implement correctly. Very small levels of contamination can require lengthy detector recovery periods. This means that correct implementation, particularly with respect to the pneumatic system, is critical for reliable results.

Several manufactures make closely related systems. However, we work with the VICI or Valco PDD system. This is a pulsed discharge detector (PDD) for GC systems with helium carrier gas.

VICI (Valco) PDID Implementation

The VICI or Valco PDD is a very sensitive and universal detector. However, this also means that any contamination from ambient gas, column bleed or other sources will degrade detector performance. Therefore, proper implementation is critical.

PDD for the Electronics Industry

We have designed and built Agilent 6890 GC systems with PDD detectors for top performance levels. The system includes a semiconductor-grade helium gas-delivery system built into the Agilent Technologies 6890 GC for contamination-free long-term operation. Proper choice of pneumatic components, valves, regulators and fittings helps reduce or eliminate many of the problems that can occur with the PDD.

Valve actuation with the PDD

Valve implementation with the PDD must be done correctly to minimize detector baseline and carrier gas contamination problems. We use special purged valve housings and fittings to minimize baseline problems with the PDD.

Quotation and Purchasing Information

Please contact Diablo Analytical to discuss your specific application requirements and to receive a project quotation.

Diablo Analytical, Inc.

1110 Burnett Ave, Suite C
P.O. Box 5889
Concord, CA 94524

Phone: (925) 609-1150
Fax: (925) 609-9360
E-Mail: info@diabloanalytical.com