Compatibility of GC septa with sample matrix

that matrix. Just as with any sample preparation technique, changes in the sample matrix you work with will influence your precision, accuracy, and chromatographic results. Step 4: If the problem persists after removing the sample matrix from the process, then start systematically removing the remaining possible sources of the problem. These

Sep 20, 2017 · Apart from the ingress of CO 2 to the eluent reservoir which causes a gradual (but small) lowering of pH on standing, the only place within the HPLC system where pH may change dramatically (and hence require a buffer) is at the head of the HPLC column where the sample diluent and eluent mix. In this microcosmic situation, the effect of a good

responses after the addition of salt to the sample matrix. Table II lists most of the common salts used for salting-out procedures. Phase Ratio The phase ratio (β) is defined as the relative volume of the headspace compared to volume of the sample in the sample vial (Figure 2). Lower values for β (i.e., larger

Dec 6, 2022 · GC Septa can originate the ghost peaks in many ways: septa itself, adsorption of organic, mineral acids, alcohols, glycols, and amines to its surface [8] or during its storage, multiple piercing of septa and adsorbed sample vapor from old injections [3]. GC septa are made of many materials, but polytetrafluoroethylene (PTFE) and siloxane-based

and are intended for single injection use with aqueous based sample mixtures. Polypropylene septa offer better solvent compatibility compared to polyethylene, but piercing force is slightly higher. Viton (V1) septa Viton septa are used in situations where a resealable septum is required for a sample matrix that aggressively attacks all other

20 mm Butyl, Pre-assembled Cap/Septa/Spring 100 N9306269 Clear 20 mL Headspace with Write-On Patch and Fill Lines Gray Butyl, Kit Unassembled Cap/Septa/Spring 100 N9306270 Gray Butyl, Kit Unassembled Cap/Septa/Spring 1000 N9306271 PTFE/Red Rubber Septa, Pre-assembled Cap/Septa/Spring 1000 N9302978

guide. Compatibility within a chemical class can vary according to the molecular weight of the solvent, other components in the sample, the temperature, as well as other factors. Phenomenex recommends that you try different vial septa materials to determine the best one for your combination of sample type, solvent and analytical detector.

sample (Figure 1) This process consists of inserting the SPME device into the sample matrix and exposing the phase to the sample. The target analytes are either adsorbed or absorbed (phase dependent) from the sample to the phase. After reaching the equilibrium state, the phase is retracted into the needle and removed from the sample vessel. 2.

interact with the analyte in your sample matrix as well as the sampler needle. Choose a material that is as inert as possible to your sample analyte and makeup solvents. Table 1 shows the range of septum materials and their corresponding compatibilities to a range of common solvents used in sample preparation.

sample, or the headspace above the sample, and the fiber. The analytes on the fiber are then directly thermally desorbed in the GC injector and transferred to the GC column. SPME concentrates analytes on the fiber, and the desorption step delivers them rapidly to the column. Thus, detection limits are minimized. SPME is compatible with analyte

Our vials are also compatible with other manufacturers’ HPLC and GC instruments. If you’re looking for a reliable supplier for sample vials in Singapore, Shimadzu is the brand you can trust. We’ve got various types of vials, caps, and septa in a wide range of volumes, dimensions and colours to best suit your needs.

Sample Vials Sample Vial Septa and Caps There are two types of septa used with crimp caps and screw- on caps, each with different resealing characteristics and different resistance to solvents. Septum material Compatible with Incompatible with Resealability Maximum temperature* PTFE/butyl rubber PTFE resistance until punctured, Chlorinated

Solid Phase Microextraction (SPME) is a fast, solvent-less sample extraction technique. It is used for extracting organics from a matrix (solid, liquid, or gaseous) into or onto a stationary phase immobilized on a fiber. In SPME, analytes establish equilibria among the sample matrix, the headspace above the sample, and a polymer-coated fused fiber.

GC/MS chromatograms of solvent blank with PTFE/silicone septa and High Performance septa were shown to be equivalent with minimal differences, indicating High Performance septa are compatible with common headspace solvents. 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 18.00 20.00 22.00 0 1e+07 2e+07 3e+07 4e+07. Major septa contamination

sample introduction into a single solvent-free step. Analytes in the sample are directly extracted and concentrated to the extraction fibre. The method saves preparation time and disposal costs and can improve detection limits.5 It has been routinely used in combination with gas chromatography (GC) and GC/mass spectrometry (GC/MS) and successfully