DB-35ms Low-Bleed

DB-35ms Low-Bleed

DB-35ms Low Bleed GC/MS Columns

Agilent J&W DB-35ms columns are precision-engineered mid-polarity GC/MS columns designed to provide exceptional inertness, highly stable retention, and very low bleed across a wide temperature range. As a close equivalent to USP Phase G42, DB-35ms delivers predictable selectivity for a broad spectrum of analytes, making it a strong fit for regulated, validated, and multi-laboratory methods.

Built on a 35% phenyl – 65% dimethylpolysiloxane stationary phase, DB-35ms offers increased polarity compared to traditional 5-phase columns, enabling enhanced separation of complex or closely eluting compounds. This mid-polarity profile makes DB-35ms particularly effective in confirmation analysis, where complementary selectivity is needed to verify identity and enhance confidence in GC/MS results.

The bonded and cross-linked design ensures strong thermal stability and supports solvent rinsing, extending column lifetime through repeated high-temperature cycles. With an extended operating range up to 340/360 °C, DB-35ms performs reliably in demanding high-temperature methods and maintains excellent inertness for active or adsorptive analytes, including acidic, basic, and multi-functional compounds.

Its ultra-low bleed characteristics improve signal-to-noise ratios and preserve mass spectral clarity, making DB-35ms a strong choice for forensic toxicology, environmental SVOCs analysis, pesticide confirmation, pharmaceutical impurity profiling, and any GC/MS workflow requiring complementary selectivity and high-precision quantitation.

Key Definitions â–¸
Mid-Polarity Stationary Phase
A stationary phase with moderate polarity—such as the 35% phenyl, 65% dimethylpolysiloxane composition of DB-35ms—providing enhanced selectivity for multi-functional or closely eluting compounds compared to non-polar 5-phase columns.
USP Phase G42
A United States Pharmacopeia classification corresponding to a 35% phenyl methylpolysiloxane stationary phase. DB-35ms is a close equivalent, supporting method alignment and regulatory compliance in pharmaceutical and analytical workflows.
Confirmation Column
A GC column used alongside a primary column to verify analyte identity, retention behavior, and selectivity. Mid-polarity columns like DB-35ms offer complementary performance that strengthens confidence in GC/MS results.
Bonded and Cross-Linked
A manufacturing method in which the stationary phase is chemically bonded to the column wall and reinforced by cross-linking. This improves thermal stability, durability, and compatibility with solvent rinsing, useful for demanding GC/MS workflows.
Extended Temperature Range (340/360 °C)
The maximum isothermal/programmable oven temperatures a column can withstand. DB-35ms operates up to 340 °C (isothermal) and 360 °C (programmed), supporting high-temperature GC/MS analyses for semivolatiles, contaminants, and complex matrices.
Frequently Asked Questions â–¸
What makes DB-35ms different from traditional 5% phenyl columns?
DB-35ms has a 35% phenyl, 65% dimethylpolysiloxane stationary phase, providing mid-polarity selectivity that differs significantly from non-polar 5-phase (5%-phenyl) columns. This enhanced polarity improves separation of multi-functional or closely eluting compounds, making it ideal for confirmation analysis and complex environmental workflows.
What types of applications benefit most from DB-35ms columns?
DB-35ms is widely used in environmental semivolatiles (SVOCs), pesticide confirmation, pharmaceutical impurity profiling, forensic toxicology, petrochemical analysis, and any GC/MS workflow requiring complementary selectivity and high mass spectral clarity.
Why is DB-35ms considered a strong confirmation column for GC/MS?
Its mid-polarity phase provides different selectivity than traditional 5-phase columns, helping verify compound identity and retention time. DB-35ms therefore enhances confidence in complex analyses by providing distinctive separation patterns for confirmation workflows.
Can DB-35ms operate at high temperatures?
Yes. DB-35ms is rated for an extended temperature range up to 340 °C (isothermal) and 360 °C (programmed). This makes it suitable for high-temperature GC/MS methods and robust enough to handle complex matrices without sacrificing inertness or stability.
Does DB-35ms support solvent rinsing for maintenance?
Yes. The bonded and cross-linked phase allows solvent rinsing to remove non-volatile residues, restore chromatographic performance, and extend column lifetime—especially helpful for environmental and industrial samples that contain heavy matrices.