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TEOM 1405DF Ambient Particulate Monitor Operator's Manual Manual / Product Insert

  • Version: FEB.2016
Catalog # TEOM1405DF

Temporal-spatial analysis of U.S.-Mexico border environmental fine and coarse PM air sample extract activity in human bronchial epithelial cells Citations & References

  • Authors: Lauer, FT; Mitchell, LA; Bedrick, E; McDonald, JD; Lee, WY; Li, WW; Olvera, H; Amaya, MA; Berwick, M; Gonzales, M; Currey, R; Pingitore, NE Jr; Burchiel, SW
  • Journal: TOXICOLOGY AND APPLIED PHARMACOLOGY
Catalog #

Effects of inhaled ambient particulate matter on pulmonary antimicrobial immune defense. Citations & References

  • Authors: Zelikoff JT, Chen LC, Cohen MD, Fang K, Gordon T, Li Y, Nadziejko C, Schlesinger RB
  • Journal: Inhal Toxicol
  • PubMed ID: 12528043

Temporal-spatial analysis of U.S.-Mexico border environmental fine and coarse PM air sample extract activity in human bronchial epithelial cells. Citations & References

  • Authors: Lauer FT, Mitchell LA, Bedrick E, McDonald JD, Lee WY, Li WW, Olvera H, Amaya MA, Berwick M, Gonzales M, Currey R, Pingitore NE Jr, Burchiel SW
  • Journal: Toxicol Appl Pharmacol
  • PubMed ID: 19410595

I am getting inaccurate results/poor reproducibility with the Qubit Protein Assay Kit. Can you offer some tips? Product FAQ

Answer

Here are possible causes and solutions:

- The kit has expired or has been stored incorrectly: When properly stored, the components of the Qubit Protein Assay Kit should be stable for at least 6 months. Upon receipt, the kit can be stored at 4 degrees C. Components A and B can be stored at ambient temperature and Components C-E can be stored at ≤4 degrees C. Protect Component A from light. High degradation of the BSA standard 2 and 3 will result in a decrease in signal and a “Standards Incorrect” error warning upon calibration. Replace the kit.
- Old calibration data was used: Best practice is to prepare fresh calibration standards at the same time as the samples to take into account any changes in assay conditions.
- Incorrect tubes were used: Use the recommended Qubit Assay Tubes (Cat. No, Q32856) or Axygen PCR-05-C tubes. Other 0.5 mL thin-walled PCR tubes may work as well, but performance is not guaranteed. Avoid opaque tubes, as these will block the light path.
- Tubes contain bubbles or particulates that are scattering the light: Pipette gently to avoid the introduction of bubbles. Spin down tubes before measuring to remove bubbles or particulates. Spin down samples to remove particulates before adding an aliquot to the Qubit working solution.
- Inaccurate pipetting: The Qubit assay will accept 1-20 µL of sample, but pipetting very low volumes, especially 1-2 µL is typically very inaccurate, especially with viscous samples. If possible, pipette at least 5 µL for more consistent results.
- The temperature of the assay is changing: Make sure that the Component B buffer is at ambient temperature before use and avoid leaving the samples in the Qubit instrument or near an exhaust fan or other heat source that would warm up the samples.
- Contamination in buffer causing high background: High buffer contamination will show up as an increase in the relative fluorescence (RFU) of the background, measured with the standard tube 1 blank, and eventually will trigger a “Standards Incorrect” error warning on calibration. Replace the kit.
- Sample buffer contains detergents: Qubit protein assay is a detergent-based assay, utilizing an environmentally sensitive dye that fluoresces in the presence of detergents; therefore, only very low concentrations of additional detergents are tolerated in the assay, as listed in Table 2 in the manual (https://tools.thermofisher.com/content/sfs/manuals/Qubit_Protein_Assay_UG.pdf).
- Sample buffer contains other components that are affecting the assay: The Qubit protein assay is generally tolerant of reducing reagents, salts, free nucleotides, amino acids, DNA, and solvents. Table 2 in the manual (https://tools.thermofisher.com/content/sfs/manuals/Qubit_Protein_Assay_UG.pdf) lists acceptable concentrations for many common contaminants. If you have a contaminant you think is affecting the quantitation, then prepare duplicate standard tubes, and spike the contaminant into one set of tubes and run them as samples. If the effect is not too substantial, then spike the buffer into the standards when performing the calibration to account for buffer composition effects.

Answer Id:: E15593

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Diesel exhaust inhalation and assessment of peripheral blood mononuclear cell gene transcription effects: an exploratory study of healthy human volunteers. Citations & References

  • Authors: Peretz A, Peck EC, Bammler TK, Beyer RP, Sullivan JH, Trenga CA, Srinouanprachnah S, Farin FM, Kaufman JD
  • Journal: Inhal Toxicol
  • PubMed ID: 17987463

Oxidatively damaged DNA and its repair after experimental exposure to wood smoke in healthy humans Citations & References

  • Authors: Danielsen, PH; Braeuner, EV; Barregard, L; Saellsten, G; Wallin, M; Olinski, R; Rozalski, R; Moller, P; Loft, S
  • Journal: MUTATION RESEARCH-FUNDAMENTAL AND MOLECULAR MECHANISMS OF MUTAGENESIS
Catalog #
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