Physicochemical characterization and quantification of nanoplastics: applicability, limitations and complementarity of batch and fractionation methods.

A comprehensive physicochemical characterization of heterogeneous nanoplastic (NPL) samples remains an analytical challenge requiring a combination of orthogonal measurement techniques to improve the accuracy and robustness of the results. Here, batch methods, including dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing (TRPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM), as well as separation/fractionation methods such as centrifugal liquid sedimentation (CLS) and field-flow fractionation (FFF)-multi-angle light scattering (MALS) combined with pyrolysis gas chromatography mass spectrometry (pyGC-MS) or Raman microspectroscopy (RM) were evaluated for NPL size, shape, and chemical composition measurements and for quantification. A set of representative/test particles of different chemical natures, including (i) polydisperse polyethylene (PE), (ii) (doped) polystyrene (PS) NPLs, (iii) titanium dioxide, and (iv) iron oxide nanoparticles (spherical and elongated), was used to assess the applicability and limitations of the selected methodologies. Particle sizes and number-based concentrations obtained by orthogonal batch methods (DLS, NTA, TRPS) were comparable for monodisperse spherical samples, while higher deviations were observed for polydisperse, agglomerated samples and for non-spherical particles, especially for light scattering methods. CLS and TRPS offer further insight with increased size resolution, while detailed morphological information can be derived by electron microscopy (EM)-based approaches. Combined techniques such as FFF coupled to MALS and RM can provide complementary information on physical and chemical properties by online measurements, while pyGC-MS analysis of FFF fractions can be used for the identification of polymer particles (vs. inorganic particles) and for their offline (semi)quantification. However, NPL analysis in complex samples will continue to present a serious challenge for the evaluated techniques without significant improvements in sample preparation.

Psychosocial well-being in postpartum women with congenital heart disease.

Background: Improved treatment options for congenital heart disease (CHD) lead to a growing number of women with CHD at reproductive age. Due to physical and psychological burden, pregnancies in women with CHD often count for high-risk. Resulting emotional distress can adversely impact pregnancy, motherhood and fetal health. The present study aims to retrospectively investigate mental outcomes and indices of adjustment in women with CHD before, during and after pregnancy. The novel concept of illness identity is applied to explain how patients experience and integrate their CHD into their identities. Methods: Patient-reported outcome measures on mental functioning and illness identity were assessed in a sample of 121 postpartum women with CHD [mean age: 42.7±9.2 (range, 27-81) years] at the German Heart Centre Munich between August and November 2021 in a cross-sectional design. Descriptive analyses, correlations and linear regression models were calculated. Results: Retrospectively assessed prevalence of emotional distress before giving birth was high (47.0%) and peaked shortly after childbirth in terms of elevated symptoms of postpartum depression and trauma. During the course of maternity, emotional distress decreased significantly (24.1%, P<0.001). Overall, postpartum women demonstrated high scores in functional illness identity states (i.e., acceptance and enrichment) and low scores in dysfunctional states (i.e., rejection and engulfment). CHD severity was not directly associated with mental outcomes (P>0.05), whereas maternal cardiovascular risk, according to the WHO classification, was significantly associated with a higher prevalence of postpartum trauma (t=2.485, P=0.015). Conclusions: Postpartum mental health problems, such as (postpartum) depression, anxiety, and posttraumatic stress can become a serious burden which might be detrimental to the mother's well-being and her infant's development. Present findings emphasise the urgent need for a holistic approach focusing on pregnant women with CHD starting at the prepartum stage to prevent adverse consequences and promote maternal well-being. Illness identity might become an important target construct for clinical practice as it may positively and enduringly influence mental well-being of pregnant women with CHD.