A specially moulded seal with a PTFE insert. Sealing surface of Butyl and PTFE affects a more positive seal than non-PTFE-faced septa. Ideal choice for temperatures below 125°C. Good sealing characteristics, excellent resistance to most solvents with reduced coring and high puncture tolerance.
Mar 16, 2022 · Carryover contamination is often blamed on the ultra-sensitive property of the PCR technique, but the generation of a superfluous quantity of amplicons is also a contributing factor. Being a cyclic process, PCR keeps duplicating the target until the primers are depleted [ 15 ] and generates millions to billions of amplicons.
Aug 25, 2022 · Cross-contamination of biological samples during handling and preparation, is a major issue in laboratory setups, leading to false-positives or false-negatives. Sample carryover residue in pipette
Jan 2, 2006 · When the needle pierces the septum, the rubber is exposed to the sample by either headspace or direct contact, which will affect the quality of the data in various ways. This application note discusses the influences of pierced PTFE/silicone septa in GC-MS experiments. Two examples are given: the loss of nonpolar volatile organic compounds
Our closures with septa are made in a wide variety of sizes and materials ensuring you have the right combination for your sample type and analysis temperature. 9 mm Pre-Assembled Blue Polypropylene Screw Cap with Pre-Slit PTFE/Silicone Septa, 100/pk | PerkinElmer
The septum forms a barrier between your sample analyte in the vial and the outside atmosphere. This barrier protects your sample from external contamination while allowing a needle (from a manual or automatic syringe) to enter the vial, and extract the sample for the next stage of separation.
The chart below ofers a starting point to help you select septa that will help prevent contamination and avoid damage. Multiple injection? Storage temperature? Good resealability properties necessary -40 °C -40 °C -60 °C natural rubber/TEF natural rubber/TEF; butyl/PTFE red rubber/ PTFE silicone/ PTFE Thin, fragile needle?
The sample preparation procedure should be specified in the sample analysis procedure and should be included as part of the sample and analysis plan (SAP) or quality assurance project plan (QAPP). This procedure should demonstrate that extreme care is taken to prevent sample contamination during preparation and extraction.
the solvent. PTFE/Silicone septa are ideal for use in most HPLC and GC applications where resealability and purity are critical. Pre-slit PTFE/silicone septa Pre-slit septa are offered in many of the same formulations as for non-slit PTFE/silicone septa and shares most of the physical and chemical characteristics.
Nov 1, 2006 · Sample carryover was not observed for CK and albumin (< 5% difference in comparison to the reference values). Carryover was found to be minimal (≤ 0.2%). In an evaluation of the Abbott Architect c8000, Pauli et al. studied specimen carryover by testing 3 replicates of high concentration samples followed by nine replicates of low concentration
Both types of silicone and butyl rubber septa have a PTFE barrier layer which faces the sample, which reduces the contact between the sample and the silicone and butyl rubber. Before the PTFE layer is punctured, the chemical compatibility properties of the PTFE will
STUDY DESIGN AND QUANTIFICATION OF CARRYOVER. In order to examine the impact of the optimized injector design on sample carryover, multiple compounds with varying chemical properties were analyzed on the Alliance HPLC System, and the 2018 Alliance HPLC System equipped with the e2695 Enhancement Kit.
Oct 15, 2004 · Strasser and Varadi recently reported two examples of ghost peaks occurring by contamination of the injected sample solution [50]. They found that ghost peaks were observed in the second and later injections from sample vials capped with PTFE-rubber septa, whereas fewer ghost peaks were observed using a more inert PTFE-silicon-PTFE septa.
Sep 9, 2019 · Reverse order of draw using closed phlebotomy systems is widely accepted as a major cause of K-EDTA contamination based on an early report. 8 It has been postulated that this occurs by K-EDTA backflow into the venesection system by collecting blood first into K-EDTA tubes, which is subsequently dispensed into the following sample tubes.
• Can change to sample from different heights in the vial - A setpoint of -2 mm will sample 1.6 mm from the vial bottom - Range is -2 mm to 30 mm • Example uses: - Samples with sediment (although properly filtering the sample is ideal) - Sampling from higher in the sample vial in liquid-liquid extractions - Small volume sampling
