Species- and organ-specificity of secretory proteins derived from human prostate and seminal vesicles

Polyclonal antibodies against semenogelin (SG) isolated from human seminal vesicle secretion and acid phosphatase (PAP), β‐microseminoprotein (β‐MSP), and Prostate‐Specific Antigen (PSA) derived from human prostatic fluid, as well as a monoclonal antibody against β‐MSP were used for immunocytochemical detection of the respective antigens in different organs from different species. SG immunoreactivity was detected in the epithelium of the pubertal and adult human and in monkey seminal vesicle, ampulla of the vas deferens, and ejaculatory duct. PAP, β‐MSP, and PSA immunoreactivities were detected in the pubertal and adult human prostate and the cranial and caudal monkey prostate. With the exception of a weak PSA immunoreactivity in the proximal portions of the ejaculatory duct, none of the latter antisera reacted with seminal vesicle, ampullary, and ejaculatory duct epithelium. Among the non‐primate species studied (dog, bull, rat, guinea pig) only the canine prostatic epithelium displayed a definite immunoreactivity with the PAP antibody and a moderate reaction with the PSA antibody. No immunoreaction was seen in bull and rat seminal vesicle and canine ampulla of the vas deferens with the SG antibody. The same was true for the (ventral) prostate of rat, bull, and dog for β‐MSP. The epithelium of the rat dorsal prostate showed a slight cross‐reactivity with the monoclonal antibody against β‐MSP and one polyclonal antibody against PSA. The findings indicate a rather strict species‐dependent expression of human seminal proteins which show some similarities in primates, but only marginal relationship to species with different physiology of seminal fluid

Intra-laboratory assessment of a method for the detection of TiO2 nanoparticles present in sunscreens based on multi-detector asymmetrical flow field-flow fractionation

In this study, an intra-laboratory assessment was carried out to establish the effectiveness of a method for the detection of TiO2 engineered nanoparticles (ENPs) present in sunscreen containing nano-scale TiO2 and a higher nanometer-range (approx. 200-500 nm) Ti02, as well as iron oxide particles. Three replicate measurements were performed on five separate days to generate the measurement uncertainties associated with the quantitative asymmetrical flow field-flow fractionation (AF4) measurement of the hydrodynamic radius r(h, mode1) (MALS), rh,,odei (ICP-MS), r(h, mode2) (ICP-MS), and calculated mass-based particle size distribution (d(10), d(50), d(90)). The validation study demonstrates that the analysis of TiO2 ENPs present in sunscreen by AF4 separation-multi detection produces quantitative data (mass-based particle size distribution) after applying the sample preparation method developed within the NanoDefine project with uncertainties based on the precision (u(IP)) of 3.9-8.8%. This method can, therefore, be considered as the method with a good precision. Finally, the bias data shows that the trueness of the method (u(t) = 5.5-52%) can only be taken as a proxy due to the lack of a sunscreen standard containing certified TiO2 ENPs

A critical evaluation of short columns for estimating the attachment efficiency of engineered nanomaterials in natural soils

Short, saturated packed columns are used frequently to estimate the attachment efficiency (alpha) of engineered nanomaterials (ENMs) in relatively homogeneous porous media, but a combined experimental and theoretical approach to obtain alpha-values for heterogeneous natural soils has not yet been agreed upon. Accurately determined alpha-values that can be used to study and predict ENM transport in natural soils should vary with ENM and soil properties, but not with experimental settings. We investigated the effect of experimental conditions, and used different methods to obtain soil parameters, essential to calculate alpha. We applied 150 different approaches to determine alpha-values from 52 transport experiments using short columns with 5 different natural soils and 20 and 80 nm gold- or 27 nm silver sulphide ENMs. The choice of column end-filter material and pore size appeared critical to avoid overestimating alpha owing to filter - ENM interactions and/or incomplete saturation of the column. Using a low ionic strength (4.4 x 10-5 mol L-1) artificial rain water as an aqueous medium avoided ENM homo- or heteroaggregation in all soils, as confirmed by single-particle inductively coupled plasma - time of flight mass spectrometry. ENM breakthrough curves could be modelled using colloid filtration theory assuming irreversible attachment only. alpha-Values calculated from this model, having the grain size represented by a single average size, accounting for dispersivity and effective porosity based on a prior inert tracer test, explained up to 42% of the variance in alpha as revealed by partial least squares analysis. However, column length and dispersivity remained as important experimental parameters, which calls for further standardisation efforts of column tests with ENMs in natural soils, preferably cross-validated with batch tests

First steps towards a generic sample preparation scheme for inorganic engineered nanoparticles in a complex matrix for detection, characterization, and quantification by asymmetric flow-field flow fractionation coupled to multi-angle light scattering and ICP-MS

The applicability of a multi-step generic procedure to systematically develop sample preparation methods for the detection, characterization, and quantification of inorganic engineered nanoparticles (ENPs) in a complex matrix was successfully demonstrated. The research focused on the optimization of the sample preparation, aiming to achieve a complete separation of ENPs from a complex matrix without altering the ENP size distribution and with minimal loss of ENPs. The separated ENPs were detected and further characterized in terms of particle size distribution and quantified in terms of elemental mass content by asymmetric flow-field flow fractionation coupled to a multi-angle light scattering detector and an inductively coupled plasma mass spectrometer. Following the proposed generic procedure SiO2-ENPs were separated from a tomato soup. Two potential sample preparation methods were tested these being acid digestion and colloidal extraction. With the developed method a complete SiO2-ENPs and matrix separation with a Si mass recovery >90% was achieved by acid digestion. The alteration of the particle size distribution was minimized by particle stabilization. The generic procedure which also provides quality criteria for method development is urgently needed for standardized and systematic development of procedures for separation of ENPs from a complex matrix. The chosen analytical technique was shown to be suitable for detecting SiO2-ENPs in a complex food matrix like tomato soup and may therefore be extended to monitor the existence of ENPs during production and safety control of foodstuffs, food labelling, and compliance with legislative limits

Quantification and Characterization of Nanoparticulate Zinc in an Urban Watershed

The recent expansion in the use of nanomaterials in consumer and industrial applications has led to a growing concern over their behavior, fate, and impacts in environmental systems. However, engineered nanoparticles comprise only a small fraction of the total nanoparticle mass in aquatic systems. Human activities, particularly in urban watersheds, are increasing the population of incidental nanoparticles and are likely altering the cycling of more abundant natural nanoparticles. Accurate detection, quantification, characterization, and tracking of these different populations is important for assessing both the ecological risks of anthropogenic particles, and their impact on environmental health. The urban portion of the South Platte watershed in Denver, Colorado (United States) was sampled for zinc to identify and quantify different nanomaterial sources. Single particle ICP-QMS was employed, to provide single elemental (Zn) signals arising from particle detection events. Coupling spICP-QMS to sample pre-fractionation (sedimentation, filtration) provided some insights into Zn association with nanoparticulate, colloidal, and suspended sediment phases. Single particle ICP-TOFMS (spICP-TOFMS) provided quantification across a large atomic mass range, yielding an even more detailed characterization (elemental ratios) on a particle-by-particle basis, providing some delineation of multiple sources of particles. Across the watershed, on average, 21% of zinc mass was present as zinc-only particles with a rather uniform mean size of 40.2 nm. Zinc that was detected with one or more other elements, primarily Al, Fe, and Si, is likely to be present as heteroagglomerates or within mineral colloids. Although spICP-TOFMS provides a substantial amount of information, it is still in its early stages as an analytical technique and currently lacks the requisite sensitivity to study the smallest of nanoparticles. As this technique continues to develop, it is anticipated that this methodology can be broadly applied to study sources, behavior and effects of a disparate variety of nanoparticles from both geogenic and anthropogenic origins