PlastiTrax® QC Kit
| Deuterated Polystyrene | dPS |
A reliable and reproducible microplastic analysis requires robust quality control measures. To enhance analytical precision, we use deuterated polystyrene (dPS) fragments as an internal standard for quality assurance. Due to their unique spectral properties in both infrared and Raman spectroscopy, dPS fragments can be clearly distinguished from environmental microplastics, making them ideal for recovery rate assessments, contamination monitoring, and automated quality control processes.
By adding a tablet containing a defined number of dPS particles to real-life samples, the recovery rate can be automatically determined for each measurement without additional effort. Due to its high similarity to conventional PS in terms of density and shape, dPS is ideally suited to improve the reproducibility and reliability of your microplastic analyses.
Optical Comparison of Polystyrene (PS)
and Deuterated Polystyrene (dPS)
The image shows the 50–100 µm fraction of polystyrene (PS) and deuterated polystyrene (dPS), captured using an optical microscope on a gold foil. Both fragments appear optically identical in size, shape, and contrast, highlighting their close physical similarity. Only through spectroscopic analysis dPS can be clearly distinguished from conventional PS, making it an ideal internal standard for quality control measures.
Spectral Differences in FT-IR Spectroscopy
Although polystyrene (PS) and deuterated polystyrene (dPS) appear identical under an optical microscope, they exhibit significant spectral differences. These differences result from isotopic labeling, where hydrogen (¹H) in PS is replaced by deuterium (²H) in dPS. This substitution causes a shift of CH vibrations to lower wavenumbers, appearing as CD vibrations. This characteristic shift allows for clear spectral identification of dPS, making it an ideal internal standard for microplastic analysis.
Spectral Differences in Raman Spectroscopy
The same phenomenon is observed in the Raman spectrum. While conventional polystyrene (PS) exhibits distinct CH vibrations, these are replaced by CD vibrations at lower wavenumbers in deuterated polystyrene (dPS). This spectral shift allows for a clear differentiation between PS and dPS, making dPS an ideal internal standard for microplastic analysis using Raman spectroscopy.
​Production of dPS Fragments
| Synthesis | Bulk Polymerization | Cryogenic Milling |
The synthesis of deuterated polystyrene (dPS) is carried out through thermally initiated radical polymerization of the Styrene-d8 monomer, using a radical initiator but without crosslinkers or additives. This process is identical to the industrial production of conventional polystyrene (PS). After polymerization, a solid dPS block is formed, which is then ground in a cryogenic mill to produce fragments. These fragments are subsequently sieved into different size categories, creating particle suspensions for further applications.
QC Kit with dPS​
As usual, the dPS fragments in our PlastiTrax® tablets are available in four different size fractions. Each tablet contains a precisely defined number of particles, individually determined, ranging from 50 to 150 particles per tablet. These standardized tablets ensure easy application, reliable quality control, and precise recovery assessment in microplastic analysis.