Exploring the potentialities of a biodegradable polymeric film in sample preparation: An optimized "white" protocol to extract and quantify emerging contaminants in water.

BACKGROUND: The introduction of white analytical chemistry encourages the development of methods characterized by a balance among greenness, productivity/feasibility and analytical performances. In the environmental analysis of emerging contaminants (ECs), for which high sensitivity and specificity are mandatory, the use of green and sustainable sample preparation needs to be coupled to a reliable analytical determination. Herein, an extraction method based on the use of a biodegradable polymeric film (Mater-Bi) and coupled to LC-MS/MS analysis was developed for the sensitive determination of ECs in wastewater. RESULTS: The interaction among a range of ECs and the Mater-Bi film (a commercially available patented blend of polybutylene-terephthalate, starch and fatty acids) was investigated by two sequential experimental designs, to simultaneously study several factors and optimize extraction efficiency. The final method, resembling a fabric phase sorptive extraction, involved pH and ionic strength modification of the sample, 1h extraction and desorption in ethanol. Satisfactory recoveries from real wastewater were obtained for sixteen analytes (56-116 %), as well as excellent precision (inter-day relative standard deviations below 10 % for most compounds). Matrix effect was in the range 88-116 % at the lower pre-concentration factor, but also acceptable in most cases at the higher pre-concentration factor. LODs in matrix, from 0.004 to 0.159 µg L-1, were lower than or comparable to those from recent studies employing green extraction procedures. The method demonstrated its applicability to samples from wastewater treatment plants, allowing quantification of pharmaceuticals and UV filters at the µg L-1 and ng L-1 levels, respectively. SIGNIFICANCE: For the first time, the synthetic biopolymer Mater-Bi, so far unexplored for the use in analytical chemistry, was exploited for a green, simple and extremely cheap extraction protocol. The optimized method is suitable for several ECs, guaranteeing very good accuracy, precision and specificity, also thanks to the LC-MS/MS analysis. The evaluation by green and white analytical chemistry metrics highlighted its superiority to conventional extraction methods.

Wastewater and seawater monitoring in Antarctica: Passive sampling as a powerful strategy to evaluate emerging pollution.

The Ross Sea, among the least human-impacted marine environments worldwide, recently became the first marine protected area in Antarctica. To assess the impact of the Italian research station Mario Zucchelli (MZS) on the surrounding waters, passive sampling - as well as spot sampling for comparison - took place in the effluent of the wastewater treatment plant (WWTP) and the receiving surface marine waters. Polar Organic Chemical Integrative Samplers (POCIS) were deployed for six consecutive 2-week periods from November to February in a reservoir collecting the wastewater effluent. Passive samplers were also deployed at shallow depth offshore from the wastewater effluent outlet from MZS for two separate 3-week periods (November 2021 and January 2022). Grab water samples were collected alongside each POCIS deployment, for comparison with passive sampling results. POCIS, used for the first time in Antarctica, demonstrated to be advantageous to estimate time-averaged concentrations in waters and the results were comparable to those obtained by repeated spot samplings. Among the 23 studied ECs - including drugs, UV-filters, perfluorinated substances, caffeine - 15 were detected in both grab and passive sampling in the WWTP effluent and followed similar concentration profiles in both types of sampling. High concentrations of caffeine, naproxen and ketoprofen in the dozens of µg L-1 were detected. Other compounds, including drugs and several UV filters, were detected down to sub- µg L-1 concentrations. In marine waters close to the effluent output, only traces of a drug (4.8 ng L-1) and two UV filters (up to 0.04 µg L-1) were quantified.

Polar licit and illicit ingredients in dietary supplements: chemometric optimization of extraction and HILIC-MS/MS analysis.

Many dietary supplements claim the ability to enhance sports performance and to improve the fitness of the consumers. Occasionally, along with legal ingredients, illicit compounds may be added without being labelled, leading to unintended doping. Hence, the aim of this study was to develop an analytical method to determine a set of 12 polar (logDpH=7 from -2.0 to +0.3) compounds including diuretics, stimulants, ß2-agonists, methylxanthines, and sweeteners. Hydrophilic interaction liquid chromatography was chosen as separation strategy, coupled with tandem mass spectrometry. The instrumental method was optimized using a two-step design of experiments (DoE). Firstly, a Plackett-Burman (PB) DoE was performed to identify the more influencing variables affecting peak areas and chromatographic resolution among temperature, water percentage in the mobile phase, and flow rate, as well as type and concentration of buffers. Secondly, a D-optimal DoE was set, considering only the most significant variables from the PB-DoE results, achieving a deeper understanding of the retention mechanism. Sample processing by salt-assisted liquid-liquid extraction was studied through DoE as well, and the whole method showed recoveries in the range 40-107% and procedural precision ≤11% for all analytes. Finally, it was applied to real samples, in which the four methylxanthines and two artificial sweeteners were detected and quantified in the range of 0.02-192 mg g-1. These values were compared to the quantities declared on the DS labels, when possible. Furthermore, a sequence of MS/MS scans allowed detection of a signal in one of the samples, structurally similar to the ß2-agonist clenbuterol.

Determination of polycyclic aromatic hydrocarbons in bud-derived supplements by magnetic molecular imprinted microparticles and GC-MS: D-optimal design for a fast method optimization.

Within the world of natural food supplements, organic extracts deriving from young plant meristematic tissue (bud-derivatives) are becoming attractive, thanks to their richness in bioactive molecules. This natural source is scarce, but every year, tons of plant material, including buds, come from city pruning. If this sustainable source is rather promising from a circular economy point of view, the safety of the obtained supplements must be assessed. In fact, anthropic microcontaminants, such as polycyclic aromatic hydrocarbons (PAHs), could adsorb onto the urban buds, leading to a possible contamination of the bud-derivatives. In this study, we developed a magnetic dispersive solid phase extraction (m-dSPE) based on molecularly imprinted microparticles, combined with GC-MS, to quantify the 16 priority PAHs in such extracts. The D-optimal experimental design was implemented to maximize analytes' recovery with the smallest set of experiments. The optimized method was characterized by great selectivity thanks to the molecular imprinted polymer and ease of use provided by m-dSPE. Moreover, it complies with green principles, thanks to the minimum consumption of organic solvent (1.5 mL of acetone per sample). The recoveries ranged from 76 to 100% and procedural precision was below 10% for most PAHs. Despite the matrix complexity, low quantification limits (0.7-12.6 µg kg-1) were reached. This guaranteed the PAHs' quantitation at levels below those indicated as safe by a European Community regulation on food supplements. None of the analyzed samples, coming from different anthropically impacted areas, showed concerning PAHs levels.

Solvent-Free Determination of Selected Polycyclic Aromatic Hydrocarbons in Plant Material Used for Food Supplements Preparation: Optimization of a Solid Phase Microextraction Method.

The exploitation of waste and by-products in various applications is becoming a cornerstone of the circular economy. A range of biomasses can be employed to produce food supplements. An example is a particular extract obtained from plant buds (rich in bioactive molecules), which can be easily retrieved from cities' pruning. In order to safely use this material, its possible contamination by organic pollutants needs to be estimated. A green and simple method to detect priority polycyclic aromatic hydrocarbons (PAHs) in bud samples by head space solid phase microextraction coupled to GC-MS was developed. This strategy, optimized through experimental design and response surface methodology, requires a minimal sample pre-treatment and negligible solvent consumption. The final method was found to be accurate and sensitive for PAHs with mass up to 228 Da. For these analytes, satisfactory figures of merit were achieved, with detection limits in the range 1-4 ng g-1, good inter-day precision (relative standard deviation in the range 4-11%), and satisfactory accuracy (88-105%), along with specificity guaranteed by the selected ion monitoring detection. The method was applied to bud samples coming from differently polluted areas, thus helping in estimating the safety of their use for the production of food supplements.

Using integrative samplers to estimate the removal of pharmaceuticals and personal care products in a WWTP and by soil aquifer treatment enhanced with a reactive barrier.

The need and availability of freshwater is a major environmental issue, aggravated by climate change. It is necessary to find alternative sources of freshwater. Wastewater could represent a valid option but requires extensive treatment to remove wastewater-borne contaminants, such as contaminants of emerging concern (CECs). It is urgent to develop not only sustainable and effective wastewater treatment techniques, but also water quality assessment methods. In this study, we used polar organic chemical integrative samplers (POCIS) to investigate the presence and abatement of contaminants in an urban wastewater treatment plant (WWTP) and in soil aquifer treatment (SAT) systems (a conventional one and one enhanced with a reactive barrier). This approach allowed us to overcome inter-day and intraday variability of the wastewater composition. Passive sampler extracts were analyzed to investigate contamination from 56 pharmaceuticals and personal care products (PPCPs). Data from the POCIS were used to estimate PPCPs' removal efficiency along the WWTP and the SAT systems. A total of 31 compounds, out of the 56 investigated, were detected in the WWTP influent. Removal rates along WWTP were highly variable (16-100 %), with benzophenone-3, benzophenone-1, parabens, ciprofloxacin, ibuprofen, and acetaminophen as the most effectively removed chemicals. The two SAT systems yielded much higher elimination rates than those achieved through the primary and secondary treatments together. The SAT system that integrated a reactive barrier, based on sustainable materials to promote enhanced elimination of CECs, was significantly more efficient than the conventional one. The removal of the recalcitrant carbamazepine and its epoxy- metabolite was especially remarkable in this SAT, with removal rates between 69-81 % and 63-70 %, respectively.

A Review on Polyethersulfone Membranes in Polar Organic Chemical Integrative Samplers: Preparation, Characterization and Innovation.

The membranes in polar organic chemical integrative samplers (POCIS) enclose the receiving sorbent and protect it from coming into direct contact with the environmental matrix. They have a crucial role in extending the kinetic regime of contaminant uptake, by slowing down their diffusion between the water phase and the receiving phase. The drive to improve passive sampling requires membranes with better design and enhanced performances. In this review, the preparation of standard polyethersulfone (PES) membranes for POCIS is presented, as well as methods to evaluate their composition, morphology, structure, and performance. Generally, only supplier-related morphological and structural data are provided, such as membrane type, thickness, surface area, and pore diameter. The issues related to the use of PES membranes in POCIS applications are exposed. Finally, alternative membranes to PES in POCIS are also discussed, although no better membrane has yet been developed. This review highlights the urge for more membrane characterization details and a better comprehension of the mechanisms which underlay their behavior and performance, to improve membrane selection and optimize passive sampler development.

An optimized processing method for polar organic chemical integrative samplers deployed in seawater: Toward a maximization of the analysis accuracy for trace emerging contaminants.

Passive sampling of emerging contaminants (ECs) in seawater represents a challenge in environmental monitoring. A specific protocol for Polar Organic Chemical Integrative Sampler (POCIS) processing may be necessary when dealing with marine applications, due to the peculiarity of the considered matrix. Herein, both the instrumental LC-MS/MS analysis and the sampler processing for the determination of 22 ECs in seawater were carefully optimized. The study entailed a test simulating POCIS sorbent exposure to seawater as well as the processing of replicated field POCIS with different elution solvents. The final method involved washing the sorbent with water, to eliminate most salts, and a two-step elution, by using methanol and a small volume of a dichloromethane-isopropanol mixture. With this protocol, recoveries between 58 and 137% (average 106%) were obtained for most analytes, including non-steroidal anti-inflammatory drugs, UV-filters, perfluorinated substances and caffeine. Still, the protocol was not suitable for very hydrophilic compounds (recovery under 20% for artificial sweeteners and the pharmaceutical salbutamol), which also showed remarkable ion suppression (matrix effects in the range 4-46%). For all other chemicals, the matrix effects were in the range 67-103% (average 86%), indicating satisfactory accuracy. Also, the overall method showed high sensitivity (detection limits in the range 0.04-9 ng g-1 of POCIS sorbent) and excellent specificity, thanks to the monitoring of two "precursor ion-product ion" MS transitions for identity confirmation. The method was applied to samplers deployed in the Ligurian coast (Italy), detecting caffeine, bisphenol A, ketoprofen and two UV-filters as the most concentrated in the POCIS sorbent.

The study of polar emerging contaminants in seawater by passive sampling: A review.

Emerging Contaminants (ECs) in marine waters include different classes of compounds, such as pharmaceuticals and personal care products, showing "emerging concern" related to the environment and human health. Their measurement in seawater is challenging mainly due to the low concentration levels and the possible matrix interferences. Mass spectrometry combined with chromatographic techniques represents the method of choice to study seawater ECs, due to its sensitivity and versatility. Nevertheless, these instrumental techniques have to be preceded by suitable sample collection and pre-treatment: passive sampling represents a powerful approach in this regard. The present review compiles the existing occurrence studies on passive sampling coupled to mass spectrometry for the monitoring of polar ECs in seawater and discusses the availability of calibration data that enabled quantitative estimations. A vast majority of the published studies carried out during the last two decades describe the use of integrative samplers, while applications of equilibrium samplers represent approximately 10%. The polar Chemcatcher was the first applied to marine waters, while the more sensitive Polar Organic Chemical Integrative Sampler rapidly became the most widely employed passive sampler. The organic Diffusive Gradients in Thin film technology is a recently introduced and promising device, due to its more reliable sampling rates. The best passive sampler selection for the monitoring of ECs in the marine environment as well as future research and development needs in this area are further discussed. On the instrumental side, combining passive sampling with high resolution mass spectrometry to better assess polar ECs is strongly advocated, despite the current challenges associated.

Unravelling the role of membrane pore size in polar organic chemical integrative samplers (POCIS) to broaden the polarity range of sampled analytes.

Polar organic chemical integrative samplers (POCIS) are widely used in their standard configuration for sampling contaminants in water bodies. A wider polyethersulfone (PES) membrane pore size was employed in POCIS exposed in a static calibration experiment to investigate the uptake of 21 emerging contaminants ranging from hydrophilic (perfluoroalkyl compounds, xanthines, an artificial sweetener) to more hydrophobic compounds (pharmaceuticals, oestrogens, UV filters). Compared to standard POCIS with 0.1-µm pore size PES membranes, the POCIS with 5-µm pore size PES membranes did not increase sampling rates for compounds of relatively low and mid-hydrophobicity. However, the uptake of more hydrophobic and anionic compounds, which either poorly diffuse through or are retained within the standard 0.1-µm PES membrane, showed a marked increase. This led to the first ever recorded sampling rates for triclosan (0.249 L day-1) and two UV filters (0.075-0.123 L day-1). Based on these results, more attention should be placed on the choice of the appropriate membrane for each POCIS application. The most suitable configuration depends on the studied compound physico-chemical characteristics-such as the polarity and the compound membrane-to-sorbent partitioning coefficient-but also on the site conditions (deployment time, fouling, flow variations, et.).

Experimental Design Step by Step: A Practical Guide for Beginners.

Inside the world of chemometrics, a fundamental role is played by the experimental design. Although introduced almost a century ago (1935), it is still not widely employed by chemists and its usefulness continues to be underestimated. When asking why, the answers are often the following: it is too difficult to apply and too much experimental effort is required. Actually, a deeper knowledge on the topic could offer a different point of view. The aim of the present tutorial is to introduce the experimental design to beginners, by providing the theoretical basic principles as well as a practical guide to use the most common designs, from the experimental plan to the final optimization. Response surface methodology will be discussed, and the main terms related to model computation and statistical evaluations usually performed by software will be explained, in order to give suitable tools to properly use them.

An innovative sampling approach combined with liquid chromatography-tandem mass spectrometry for the analysis of emerging pollutants in drinking water.

In this work, an innovative sampling and preconcentration method followed by analysis with liquid chromatography coupled to tandem mass spectrometry with electrospray ionization (LC-ESI-MS/MS) was developed for the determination of different emerging pollutants (five anti-inflammatory drugs and one antibacterial agent) in water matrices. Thin-film microextraction blades, consisting of stainless steel blades with a coating made of divinylbenzene, have been employed. The blades, fixed onto a stainless steel support, were mounted on a laboratory stirrer with adjustable speed, immersed in water samples and eluted with methanol. The analytical procedure was developed, carefully optimizing stirring speed and extraction time. A good reproducibility among the blades was observed; quantitation limits at the ng L-1 level were achieved. Calibration curves were constructed by applying the whole procedure to tap water samples, free from analytes, spiked with standards in the concentration range 0.01-2 µg L-1 ; good linearity was obtained, with R2 between 0.9984 and 0.9991. The optimized method was applied to tap and surface waters; two anti-inflammatory drugs were detected at the ng L-1 level in surface water. In one sample, diclofenac and naproxen were measured at 26 ± 5 and 15 ± 1 ng L-1 , respectively; only diclofenac was quantified in the other sample at 14 ± 3 ng L-1 .

A clean-up strategy for identification of circulating endogenous short peptides in human plasma by zwitterionic hydrophilic liquid chromatography and untargeted peptidomics identification.

Short peptides, namely di- tri- and tetra peptides, have been proven to play an important diagnostic role in several diseases. Therefore, the development of an analytical approach for their detection and identification is nowadays an important research goal. This paper describes an analytical procedure able to overcome the issues of short peptide isolation, clean-up and identification in plasma samples. Four different protocols were compared and tested to maximize both recovery and total number of identifications of short circulating plasma endogenous peptides. The purified peptides, coming from the four different tested protocols, were separated by zwitterionic hydrophilic liquid chromatography coupled to high-resolution mass spectrometry with the purpose of accomplishing an untargeted investigation based on suspect screening for short peptides in plasma. In particular, the use of Phree™ Phospholipid removal cartridge in combination with a purification step by solid phase extraction on a graphitized carbon black sorbent allowed the identification of the largest number of amino acid sequences (91 short peptides). The clean-up procedure allowed to tackle the issue of the low abundance of such peptides and their suppression during mass-spectrometric analysis. The results indicated that sample preparation is therefore fundamental for short peptide analysis in plasma samples.

New insights in hemp chemical composition: a comprehensive polar lipidome characterization by combining solid phase enrichment, high-resolution mass spectrometry, and cheminformatics.

The chemical composition of Cannabis sativa L. has been extensively investigated for several years; nevertheless, a detailed lipidome characterization is completely lacking in the literature. To achieve this goal, an extraction and enrichment procedure was developed for the characterization of phospholipids and sulfolipids. Firstly, a study on the solid-liquid extraction was performed, to maximize the recovery of the considered lipids; the best procedure consisted of a simple extraction with a mixture of methanol and chloroform (1:1, v/v). The hemp extracts were analyzed by ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry and lipids were tentatively identified by Lipostar. To improve the number of identifications, an enrichment method, based on graphitized carbon black solid phase extraction, was evaluated to fractionate phospholipids and sulfolipids into separate eluates. Recovery and matrix effects of the procedure were determined on a mixture of standard lipids, containing representative compounds for each considered lipid class. The optimized method allowed the tentative identification of 189 lipids, including 51 phospholipids and 80 sulfolipids, in the first and second fractions, respectively. The detection of only 6 sulfolipids in the first fraction and 9 phospholipids in the second fraction proved the efficacy of the fractionation method, which also allowed the number of lipid identifications to be increased compared to the same procedure without enrichment, which scored 100 lipids. Finally, a semi-quantitative analysis permitted the hemp polar lipidome to be characterized. The results of this study allow knowledge of the hemp chemical composition to be improved with a detailed description of its phospho- and sulfolipid profiles. Graphical abstract.

Phospholipidome of extra virgin olive oil: Development of a solid phase extraction protocol followed by liquid chromatography-high resolution mass spectrometry for its software-assisted identification.

The determination of phospholipids in olive oil is challenging due to their low concentration. For this reason, a comparison of two solid phase extraction procedures, namely weak anionic exchange (WAX) and graphitized carbon black (GCB), is presented for the enrichment of phospholipids. Analyses were performed by liquid chromatography-high resolution mass spectrometry (LC-HRMS) and lipids were identified by Lipostar software. Compared to the WAX solid phase extraction, GCB demonstrated the best performance and provided 82 identified phospholipids vs only 32. The final method was validated for some representative phospholipids, showing good repeatability and recovery (63-101%). High sensitivity was reached, with detection limits in the range 9-36 ng g-1, never reported before for phospholipids in olive oil. A semi-quantitative analysis indicated phosphatidic acids and phosphatidylglycerols as the most abundant species, both in number and concentrations. The GCB-LC-HRMS-Lipostar platform can be successfully applied for a comprehensive polar lipidomic characterization of olive oils.

Enrichment procedure based on graphitized carbon black and liquid chromatography-high resolution mass spectrometry for elucidating sulfolipids composition of microalgae.

Microalgae have recently become a popular functional food due to their health benefits. Sulfolipids, a class of substances abundant in this matrix, have been reported to have interesting bioactivities, such as anti-carcinogenic activity. However, despite the potential interest in sulfolipids, a dedicated analytical method for their characterization is currently lacking but would significantly increase the coverage of sulfolipids with respect to the direct lipidomic analysis. To achieve this goal, in this work a procedure, based on graphitized carbon black solid phase extraction, was developed for clean-up and enrichment of sulfolipids (sulfoquinovosyldiacylglycerols and sulfoquinovosylmonoacylglycerols) and it was applied to spirulina (Arthrospira platensis) microalgae. A careful study of the solid phase extraction conditions was performed, first to maximize the recovery of reference standards, then to increase the total number of identified sulfolipids from the spirulina lipid extract. All samples were analysed by ultra-high performance liquid chromatography coupled to high resolution mass spectrometry and lipids were tentatively identified by Lipostar, for a reliable lipid structure assignment. The developed method was compared to the direct lipidomic analysis without enrichment, to establish the enrichment efficiency in terms of number of identifications. From the comparison, the enrichment procedure proved better and allowed the tentative identification of 199 sulfolipids, which is the largest number reported so far for the Arthrospira platensis species. The described method was validated in terms of precision, accuracy, recovery, limit of quantitation and detection for two sulfolipids. Finally, a relative lipid quantitation based on peak area was carried out on the microalgae sample, which indicated nine abundant sulfolipids as representing ca. 60% of sulfolipids in spirulina microalgae.

The experimental design approach to the optimization of a simple quick easy cheap effective rugged and safe method for the analysis of phytoestrogens in complex soy-based food.

The present paper deals with the multivariate optimization of an extraction-purification strategy for the determination of phytoestrogens (daidzein, genistein, coumestrol, formononetin, and biochanin A) in soy-based meat substitutes by high performance liquid chromatography with tandem mass spectrometry. For a reliable quantitation of these new concerning compounds in such a complex matrix, recovery and matrix effect must be carefully evaluated. Therefore, two sequential experimental designs were used to optimize the sample-pretreatment of soy-based burgers: the chosen technique was the quick, easy, cheap, effective, rugged and safe methodology, which does not require any particular facility or instrumentation. Thanks to the first screening design (Plackett-Burman), the significant factors influencing the studied responses were identified and further investigated through a response surface design (Box-Behnken). The optimal values of the variables (volume of extraction solvent mix/sample mass ratio and two clean-up sorbents) led to quantitative recoveries (97-104%) and low ion suppression (matrix effect 60-93%) for all analytes. This optimized method was characterized by low detection limits (0.2-1.5 ng/g) and excellent intraday precision (RSD 2-4%). It was applied to the determination of the considered compounds in several soy-burgers from the Italian market, detecting low ng/g levels (up to 40 ng/g) of coumestrol, formononetin, and biochanin A, and high concentrations (7.9-78 µg/g) of genistein and daidzein.

Phytoestrogens in soy-based meat substitutes: Comparison of different extraction methods for the subsequent analysis by liquid chromatography-tandem mass spectrometry.

This paper presents the development of an efficient extraction procedure followed by a high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method for the determination of five phytoestrogens (genistein, daidzein, formononetin, biochanin A, and coumestrol) in soy-based meat substitutes. Phytoestrogens are considered endocrine disrupting compounds, and their quantification is important in soy-based products, whose diffusion is increasing nowadays. The HPLC-MS/MS method, with electrospray ionization (ESI) source, was optimized to obtain high specificity and sensitivity, as well as rapidity of the analysis. Three extraction techniques were applied to soy burgers and compared: ultrasound assisted extraction, ultrasound assisted extraction followed by solid phase extraction and the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) methodology. Both ultrasound assisted extraction and QuEChERS proved to be suitable for the determination of phytoestrogens, showing high recoveries, in the range of 86% to 99% and 75% to 105%, respectively. Matrix effect was evaluated, and ion suppression was observed for coumestrol and formononetin, demonstrating the importance of matrix effect assessment when complex samples are analyzed by HPLC-ESI-MS. The complete analytical protocols provided limits of detection and quantitation in soy-burgers at the ng g-1 level for all the considered phytoestrogens. Some soy burger samples were analyzed by both ultrasound assisted extraction and QuEChERS followed by HPLC-MS/MS. High concentration levels of daidzein and genistein (2-59 µg g-1 and 2-72 µg g-1 , respectively) were found; formononetin was in the range of 5 to 26 ng g-1 , while biochanin A and coumestrol were under the limit of quantitation in all samples. The results obtained with the two different sample treatment were in good agreement, proving the precision and accuracy of the described techniques.

Organizational Contributors to the Variation in Red Blood Cell Transfusion Practices in Cardiac Surgery: Survey Results From the State of Michigan.

BACKGROUND: While large volumes of red blood cell transfusions are given to preserve life for cardiac surgical patients, indications for lower volume transfusions (1-2 units) are less well understood. We evaluated the relationship between center-level organizational blood management practices and center-level variability in low volume transfusion rates. METHODS: All 33 nonfederal, Michigan cardiac surgical programs were surveyed about their blood management practices for isolated, nonemergent coronary bypass procedures, including: (1) presence and structure of a patient blood management program, (2) policies and procedures, and (3) audit and feedback practices. Practices were compared across low (N = 14, rate: 0.8%-10.1%) and high (N = 18, rate: 11.0%-26.3%) transfusion rate centers. RESULTS: Thirty-two (97.0%) of 33 institutions participated in this study. No statistical differences in organizational practices were identified between low- and high-rate groups, including: (1) the membership composition of patient blood management programs among those reporting having a blood management committee (P= .27-1.0), (2) the presence of available red blood cell units within the operating room (4 of 14 low-rate versus 2 of 18 high-rate centers report that they store no units per surgical case, P= .36), and (3) the frequency of internal benchmarking reporting about blood management audit and feedback practices (low rate: 8 of 14 versus high rate: 9 of 18; P= .43). CONCLUSIONS: We did not identify meaningful differences in organizational practices between low- and high-rate intraoperative transfusion centers. While a larger sample size may have been able to identify differences in organizational practices, efforts to reduce variation in 1- to 2-unit, intraoperative transfusions may benefit from evaluating other determinants, including organizational culture and provider transfusion practices.

Prediction of Transfusions After Isolated Coronary Artery Bypass Grafting Surgical Procedures.

BACKGROUND: Although blood transfusions are common and have been associated with adverse sequelae after cardiac surgical procedures, few contemporaneous models exist to support clinical decision making. This study developed a preoperative clinical decision support tool to predict perioperative red blood cell transfusions in the setting of isolated coronary artery bypass grafting. METHODS: We performed a multicenter, observational study of 20,377 patients undergoing isolated coronary artery bypass grafting among patients at 39 hospitals participating in the Michigan Society of Thoracic and Cardiovascular Surgeons Quality Collaborative's PERFusion measures and outcomes (PERForm) registry between 2011 and 2015. Candidates' preoperative risk factors were identified based on previous work and clinical input. The study population was randomly divided into a 70% development sample and a 30% validation sample. A generalized linear mixed-effect model was developed to predict perioperative red blood cell transfusion. The model's performance was assessed for calibration and discrimination. Sensitivity analysis was performed to assess the robustness of the model in different clinical subgroups. RESULTS: Transfusions occurred in 36.8% of patients. The final regression model included 16 preoperative variables. The correlation between the observed and expected transfusions was 1.0. The risk prediction model discriminated well (receiver operator characteristic [ROC]development, 0.81; ROCvalidation, 0.82) and had satisfactory calibration (correlation between observed and expected rates was r = 1.00). The model performance was confirmed across medical centers and clinical subgroups. CONCLUSIONS: Our risk prediction model uses 16 readily obtainable preoperative variables. This model, which provides a patient-specific estimate of the need for transfusion, offers clinicians a guide for decision making and evaluating the effectiveness of blood management strategies.