Capillary Samples Research Articles

Considerations for quantitative in situ X-ray powder diffraction studies of solid-state reactions

The importance of sample preparation in collecting high-fidelity powder diffraction data suitable for quantitative structure and phase analysis is well established. Such powder diffraction experiments are increasingly being applied in situ, during reactions, to explore solid-state reactivity. When applied in situ, X-ray diffraction is widely used to gain insight into the mechanism and kinetics, and to identify dynamic intermediate states. Here, using a model ion-exchange reaction (NaFeO2 + LiCl → LiFeO2 + NaCl), we show that sample preparation not only influences the fidelity of powder diffraction analysis but also impacts the observed reaction progress. Specifically, we found that the observed reaction progress can differ by ∼50% depending on the capillary sample preparation. Thus, for in situ diffraction studies of solid-state reactions, packing fraction is an important and previously unrecognized consideration that impacts reproducibility and fidelity of the reaction study.

Design and Performance of a Low-Cost, Portable Platelet Counter for Point-of-Care and at-Home Use

Background Patients with recurrent or chronic moderate-to-severe thrombocytopenia can experience a marked reduction in quality of life due to the need for regular blood draws, frequent contact with the health care system, and potential for bleeding complications requiring emergency department visits and/or hospital admissions. To improve quality of life while maintaining effective platelet monitoring, we introduce a portable, point-of-care platelet counter that can be used in any health care setting or at home. Methods Obtaining a platelet count requires three components: a counter, staining modality, and erythrocyte lysing agent. The counting device described here is the Athelas One, a small cylindrical device containing a miniaturized microscope embedded with a control board. A strip containing a stained microfluidic channel approximately 10µm tall and thus suitable for a monolayer of blood cells houses the sample. An ammonium oxalate solution is used to lyse the erythrocytes in the capillary sample. Images of the blood sample are acquired and then analyzed using a convolutional neural network to yield platelet counts. To use the device, a patient pricks his or her finger and collects 20µL of blood in a K2EDTA-coated minivette. The blood is mixed with the lysing agent and inserted into the strip, which in turn is inserted into the device. A platelet count is obtained within 5 minutes. In this observational study, we enrolled 233 adults at least 21 years of age with normal platelet counts at a single teaching hospital. Non-hematological illness was allowed. Each patient's platelet count was obtained using both capillary samples processed on Athelas One and paired anticoagulated venous samples processed on a standard hematology analyzer, the Sysmex XS-1000i (SX). Platelet counts from Athelas One and SX were compared using a Passing-Bablok regression model with a Pearson correlation coefficient. Bland-Altman analysis was also performed. Confidence intervals (CI) were calculated using a Student's t-distribution. Least squares regression modeled the relationship between time necessary to collect capillary samples and bias between Athelas One and SX. Analyses were conducted in R. Results A strong linear relationship was observed between Athelas One and SX: Passing-Bablok regression revealed a slope of 0.98 and a y-intercept estimate of -16.45 (Figure), and the Pearson correlation-coefficient was 0.70. Bland-Altman statistics revealed an average percent difference of -8.66% (95% CI: -6.55% to -10.77%), reflecting a bias of Athelas One to undercount as compared with SX. In an effort to explain the predilection for undercounting, device performance was analyzed as a function of sample collection time. Least squares regression revealed a slope of -1.08 (95% CI: -1.55 to -0.61) and a y-intercept estimate of 8.16 (95% CI: -12.15 to 28.47). The Pearson correlation-coefficient was 0.54. Conclusion Athelas One compared favorably with SX. The bias for undercounting may be a consequence of a pseudothrombocytopenia phenomenon due to platelet activation and clot formation prior to sample collection, which sequesters platelets out of solution. This hypothesis is supported by the fact that longer time needed to collect the capillary sample correlated with larger negative bias between Athelas One and SX. To improve agreement, a number of methods in the counting procedure, namely sample collection, could be altered. A potential solution involves wiping the finger with an anticoagulant prior to sample collection to discourage clot formation. This proof-of-concept analysis demonstrates the plausibility of point-of-care platelet monitoring. Future work will focus on validating Athelas One in thrombocytopenic and thrombocytotic samples.

B-cell-activating factor (BAFF) and platelet-activating factor (PAF) in pregnancies complicated by maternal obesity and diabetes: a preliminary study

Objective In pregnancies complicated by maternal obesity and diabetes, a disruption in inflammatory mediators occurs, resulting in endothelial microvascular dysfunction, oxidative stress, tissue damage, and maternal and feto-neonatal complications. To outline this proinflammatory status, an innovative approach is represented by the measurement of proinflammatory cytokines. Among these biomarkers, B-cell-activating factor (BAFF) and platelet-activating factor (PAF) play a key role in metabolic regulation, immune response to infections, tissue homeostasis, and “food-related inflammation.” The aim of the present study is to investigate the blood expression of BAFF and PAF in a cohort of pregnant women affected by obesity and diabetes compared with a control group of healthy pregnant women. Methods A prospective longitudinal cohort study has been conducted on pregnant women referred to Fondazione Policlinico Universitario Gemelli IRCCS in Rome. For each pregnant woman, a capillary sample was collected with a swab in three different consecutive evaluations carried out in the three trimesters of pregnancy. Results A total of 77 pregnant women have been enrolled. No significant differences in BAFF and PAF levels were longitudinally observed between groups. Focusing on the exposed group, in the third trimester of pregnancy, both PAF and BAFF levels were lower than the basal time. Among the selected group of patients who developed Gestational Diabetes, only PAF values were longitudinally lower when compared to other groups. The multivariate analysis showed that BAFF levels were positively correlated with thyroid-stimulating hormone levels. No macrosomia, no shoulder dystocia, no major perineal lacerations at birth, and no intrauterine growth restriction were observed in the whole population. Conclusions This study supports the involvement of metabolic and proinflammatory biomarkers in the mechanisms related to pregnancy complications. Improving a good metabolic environment for obese and diabetic pregnant women could break the vicious cycle connecting inflammation, oxidative stress, and metabolic disorders.

Preliminary Assessment of the Acute Effects of Far Infrared-Emitting Garments: What Are the Possible Implications for Recovery and Performance?

Technical clothing has recently been brought into the spotlight as one of the most promising tools to improve sports performance and to enhance sports recovery. Among technical clothing items, garments engineered to emit far infrared (FIR) spectrum frequencies have come to the fore as a treatment for pain, muscle fatigue, and tissue healing due to their potential antioxidative and anti-inflammatory properties, with applications not only during recovery phases but also in the active phases of exercise. These garments, composed of fibers mixed with noble metals and/or bioceramics that respond to body infrared frequencies by returning an FIR emission backwards, are thought to improve muscle oxygenation and therefore recovery. In this double-blind, randomized, placebo-controlled, crossover study, ten male trail running athletes wore a whole-body-covering suit marketed as Accapì-FIR (Bruno Chiaruttini S.r.l., Rezzato, BS, Italy), while a total body suit with the same polyester fiber without metal components was used as control for the intervention. Parameters such as weight, height, bioimpedance parameters (BIVA), lactate from capillary sampling, salivary cortisol, and average temperatures of different body areas were obtained before and after a twelve-minute incremental work run protocol on a treadmill whilst wearing the two kinds of garment. Using the intervention suit, compared to control, statistically significant reductions in BIVA parameters such as body resistance (-6.7%) and reactance (-5.4%) were observed before and after exercise while a greater, but not significant, weight reduction was observed with the intervention suit. Decrease in resistance could be the result of a different distribution of fluids and ions due to FIR influence on capillary and superficial circulation, leading ultimately to more efficient management of body heat and promoting recovery and supercompensation. Further studies on larger samples will be necessary to confirm and clarify these results.

A-056 Data Driven Approach to Ensure Accurate Total Testosterone Results in Consumer Initiated, Home-collected Capillary Samples

Abstract Background Home-collected direct access testing (DAT) has become increasingly attractive as telehealth utilization advances. With DAT, consumers initiate their lab order and have access to clinical consulting staff. Steroid hormone concentrations are uniquely positioned for DAT due to their inherent stability and non-acute indications. Total testosterone (TT) is used to screen for or monitor treatment of hypogonadism. Once diagnosed, testosterone is administered by intramuscular or subcutaneous injection or via transdermal patch or topical gel. TT in adult men is typically between 200 and 900 ng/dL. However, in our DAT lab we were encountering a significant percentage of samples with supraphysiological TT concentrations (>1500 ng/dL). The objective of this study was to design a quality assurance workflow to differentiate whether the supraphysiological results were accurate or erroneous. Methods TT was measured using the Roche Cobas e801 immunoassay; basic assay parameters were verified per general CAP guidelines (precision, accuracy, linearity, method comparison, interferences, carryover, dilution). Additional validation experiments were performed to verify that capillary plasma was an acceptable sample type (n = 30 paired capillary/venous samples) and to determine if extreme summer temperature fluctuations would influence stability (n = 46 participants; samples subjected to temperature cycling for 72 h before re-evaluation). Self-collected capillary samples received for clinical testing with a TT concentration >1500 ng/dL were run on a 1:5 dilution (extending the clinical reportable range to 7500 ng/dL) and the sample was reflexed to luteinizing hormone (LH) and follicle stimulating hormone (FSH). Reference intervals in adult men for LH and FSH are 1.7–8.6 mIU/mL and 1.4–13.0 mIU/mL, respectively. When available, clinical notes were reviewed for additional information on exogenous hormone usage. Results All general assay parameters were within acceptable metrics. TT concentrations between capillary and venous samples had an average absolute bias of −9.2 ng/dL or −3.8% (n = 30; range = <20–823 ng/dL; y = 0.954x + 1.915; R = 0.995). Baseline and post-summer temperature cycling TT concentrations had an average absolute bias of −8.1ng/dL or −3.4% (n = 46; range = <20–716 ng/dL; y = 0.934x + 7.728; R = 0.999). Samples (n = 506) with a TT concentration >1500 ng/dL were reflexed to TT dilution and LH/FSH. Most (n = 413; 82%) had undetectable (<0.3 mIU/mL) LH/FSH and a mean TT concentration of 3356 ng/dL (SD = 1972). For 18.6% (n = 77) of this subset, we had medication information; 68 were using injectable testosterone. Elevated TT was likely a true result caused by overuse of anabolic steroids. A smaller subset of samples (n = 21) had detectable LH/FSH with mean concentration/SD of 6.1/5.2 mIU/mL for LH, 5.3/5.4 mIU/mL for FSH, and TT >7500 ng/dL. Medication notes were available for 5 of these samples and indicated that the TT results were likely caused by topical contamination (false positive). A final subset (n = 40) had detectable LH/FSH and TT between 1500 and 7500 ng/dL. These samples could not be binned into simple categories and instead were sent to the lab director for review. Conclusion Self-collected capillary specimens are acceptable for TT measurements. A quality assurance reflex to LH/FSH can support or refute the validity of supraphysiological results in a consumer initiated/DAT population.

A-379 Frequency of Reassignment of Blood Gas Sample Source at a Large Tertiary Care Hospital

Abstract Introduction Arterial blood gases analysis are central to the assessment and management of the critical patient acid-base status and its collection requires expertise and is often collected by trained respiratory therapists, nursing, and medical staff. Venous blood gases, arterialized venous blood gases, and capillary samples are however easier to collect. In this retrospective, study we examined the frequency of reassignment of blood gases results to a different sample type. Method Retrospective review of blood gases results requiring sample type reassignment collected during the last three years from January 2020 to December 2022 were obtained. Results were analyzed for concordance with sampling site and workflow analysis. Results Over the three years study period (2020 to 2022), a total of 196 samples for blood gases analysis required reassignment to a different collection site representing 0.12% of all blood gases testing. Among the 123 initial arterial collections, 72 were reassigned as venous, 40 reassigned to mixed venous sample, and one to capillary collection. Whereas, among the initial 24 venous samples collections 16 were reassigned as arterial and 8 to mixed venous collections. Additionally, among the 25 initial mixed venous collections, 16 were reassigned as arterial, 9 reassigned as venous and 3 were reassigned as capillary collections. The frequency of reassignment from arterial to venous was significantly higher compared to venous to arterial (P < 0.05) or for the reassignment in the mixed venous collections. Although a smaller number of samples were amended to capillary, capillary blood gases reflect arterial samples.There was no significant difference in the frequency of sample type reassignment between the three years of collection with the exception of a slight drop in year 2020 where the majorly of patients were of COVID-19 infection and that collections were likely performed by the same assigned medical personnel. Conclusion Common errors in blood gases collection are failure to obtain an arterial sample and accidental collection of venous samples instead often due to close proximity is common. In this retrospective review, the common reassignment is that of arterial to venous followed by arterial to mixed venous and venous to arterial sample types. Artifactual causes that may lead to misclassification of sample type include sample integrity as exposure to room air falsely reduces pCO2 and elevates pO2 giving a false impression of an arterial collection, similarly, dilution of arterial blood samples by heparin is common (inadequate blood fill of syringe) falsely lowers pCO2 both raising doubt as to the sample type.The impact of reassignment of change of sample type on outcomes and on interpretation requires analysis.

Maximizing Microsampling: Measurement of Comprehensive Metabolic and Lipid Panels Using a Novel Capillary Blood Collection Device.

Demand continues to grow for patient-centric sampling solutions that enable collection of small volumes of blood outside of healthcare facilities. Various technologies have been developed to facilitate sample collection but gaps in knowledge remain, preventing these technologies from replacing standard venipuncture. A novel blood collection device, Touch Activated Phlebotomy (TAP) II® from YourBio Health, and standard fingerstick collection using a BD Microtainer® were utilized to collect capillary serum samples. Measurements of a comprehensive metabolic and lipid panels were measured on these samples and compared to results from venous serum samples that were collected in parallel. Hemolysis was used to assess sample quality. Sample volumes obtained from self-collected TAP II samples were also determined. Correlation of capillary serum with respect to venous serum was demonstrated (R > 0.9) for professionally collected TAP II samples, self-collected TAP II samples, and professionally collected fingerstick samples for alkaline phosphatase, alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, cholesterol, high-density lipoprotein, total bilirubin, and triglycerides. Results for creatinine demonstrated acceptable correlation, however, a consistent negative bias was observed. Biases (with unacceptable correlations) were also observed for measurements of carbon dioxide and potassium. Correlative results for albumin were not consistently acceptable across the collection techniques utilized while the remaining analytes tested did not demonstrate acceptable correlations under any condition. Correlation results, however, would improve with a wider distribution of analyte concentrations. Collections of small volumes of liquid blood continue to show potential as a patient-centric solution.

Pre-analytical variables influence zinc measurement in blood samples.

Zinc deficiency continues to be a major concern for global public health. The zinc status of a target population is typically estimated by measuring circulating zinc levels, but the sampling procedures are not standardized and thus may result in analytical discrepancies. To examine this, we designed a study that controlled most of the technical parameters in order to focus on five pre-analytical variables reported to influence the measurement of zinc in blood samples, including (1) blood draw site (capillary or venous), (2) blood sample matrix (plasma or serum), (3) blood collection tube manufacturer (Becton, Dickinson and Company or Sarstedt AG & Co), (4) blood processing time (0, 4, or 24 hours), and (5) blood holding temperatures (4°C, 20°C, or 37°C). A diverse cohort of 60 healthy adults were recruited to provide sequential capillary and venous blood samples, which were carefully processed under a single chain of custody and measured for zinc content using inductively coupled plasma optical emission spectrometry. When comparing blood draw sites, the mean zinc content of capillary samples was 0.054 mg/L (8%; p<0.0001) higher than venous blood from the same donors. When comparing blood sample matrices, the mean zinc content of serum samples was 0.029 mg/L (5%; p<0.0001) higher than plasma samples from the same donors. When comparing blood collection tube manufacturer, the mean zinc content from venous blood samples did not differ between venders, but the mean zinc content from BD capillary plasma was 0.036 mg/L (6%; p<0.0001) higher than Sarstedt capillary plasma from the same donors. When comparing processing times, the mean zinc content of plasma and serum samples was 5-12% higher (p<0.0001) in samples processed 4-24 hour after collection. When comparing holding temperatures, the mean zinc content of plasma and serum samples was 0.5-7% higher (p = 0.0007 or p = 0.0061, respectively) in samples temporarily held at 20°C or 37°C after collection. Thus even with the same donors and blood draws, significant differences in zinc content were observed with different draw sites, tube types, and processing procedures, demonstrating that key pre-analytic variables can have an impact on zinc measurement, and subsequent classification of zinc status. Minimizing these pre-analytical variables is important for generating best practice guidelines for assessment of zinc status.

Balanced Fast-SpaciMS capillary configurations provide practically noninvasive channel-average measurements in catalytic monoliths

Spatially resolved capillary-inlet mass spectrometry (SpaciMS) provides a detailed picture of the spatiotemporal evolution of reaction network in catalytic monoliths. In the present work, we combine the SpaciMS experiments with a newly developed non-isothermal 3D CFD model for heterogeneously catalyzed reactive flows, including diffusion and permeation through the coated catalyst and channel wall. We explore how the capillary size and sampling rate can be balanced to minimize the impact on probed-channel conversions and provide species concentration measurements representative of the free channel average. In all studied configurations, the balanced sampling-rate fraction is noticeably higher than the corresponding capillary occlusion fraction. For a typical 350-micron capillary that occupies 11% of the channel cross- section, the balanced sampling rate represents 43% of the channel flow. The present work shows that together, a balanced SpaciMS configuration and numerical simulation provide accurate channel-averaged information of a monolithic catalyst under realistic operation conditions.

Comparability and Stability of Serum Creatinine Concentration in Capillary and Venous Blood.

Background: The use of self-collected capillary blood has several advantages over phlebotomy, as such finger-prick testing is rapidly becoming accepted as a routine sample type for adults. However, there is limited evidence that venous and capillary serum is comparable for many analytes. This study aimed to determine whether capillary samples could offer an alternative sampling method to venous samples for the assessment of serum creatinine using the enzymatic method and if this analyte was stable in unspun capillary blood for 3days. Methods: Matched capillary and venous blood samples were collected from 48 patients for the determination of serum creatinine, one set being processed on day zero, the other set being stored at ambient temperature and then processed on day three. Self-collected capillary blood was compared with phlebotomist-collected venous samples. Results: Serum creatinine concentrations from venous and capillary blood samples taken on day zero were compared to concentrations in capillary blood from day three. Data produced showed serum creatinine concentrations from capillary and venous serum to be comparable. Conclusion: It is believed that this is the first published study to determine if self-collected capillary blood sampling is an acceptable alternative to venous sampling for the measurement of serum creatinine concentration; our data indicates that there is no significant difference in results from unspun venous and capillary blood stored at room temperature for at least 3days compared to venous blood tested on the same day of collection.

Determination of Plasmodial Species Prevalence among Patients Received at Cotonou Boni Clinic during Rainy Season in the Year 2022

Aims: Malaria is a life-threatening disease caused by parasites transmitted by bites from infected female anopheles. It is a preventable and treatable illness. It remains a recurring disease among public health diseases that exposes many people to a risk of infection, including children under the age of 05 in Benin.&#x0D; Methods: To determine the prevalence of malaria and different plasmodial species at the Dr Pierre BONI Clinic, we performed venous and capillary samples on 731 patients for the realization of thick drops and blood smears between June and July 2022.&#x0D; Results: Three plasmodial species were identified in 228 patients (31%) as malaria of the 731 patients included in the study with 3 species of plasmodium found: Plasmodium falciparum (95.5%), Plasmodium malariae (2.85%), Plasmodium ovale (1.65%). Mixed or double species was also recorded in some patients: Plasmodium falciparum+ Plasmodium malariae and Plasmodium falciparum+ Plasmodium ovale. The majority of patients have the presence of trophozoites at Plasmodium falciparum, 95.5%. The parasitic density of P. falciparum is higher than that of P. malariae and that of P. ovale.&#x0D; Conclusion: Although evaluated during a period of low transmission, malaria remains a real public health problem. The distribution of the disease is closely related to the presence in the blood of plasmodial species.

ADEQUACY OF FINE NEEDLE ASPIRATION CYTOLOGY FOR CONFIRMATION OF TYPE OF THYROID LESIONS

Thyroid nodules commonly arise within an otherwise normal thyroid gland. Nodular thyroid lesions are so common that they are present as solitary or multiple nodules. Fine-needle aspiration and capillary sampling are the 2 most commonly used diagnostic techniques for assessing cytopathology of thyroid nodules. Objectives: To determine the frequency of adequacy of fine needle aspiration cytology for detecting thyroid lesions in patients with thyroid lesions. Materials and Methods: 75 patients with thyroid lesions were enrolled after meeting the inclusion criteria. Informed consent and demographic information were taken. The patient's TSH level was noted. Then, FNAC was done after collecting the specimen through FNAC, and the specimen was sent to the hospital laboratory for cytology. The diagnosis was made. All the collected information was noted and entered in SPSS version 20 for analysis. Results: In our study, the mean age of the patients was 43.20±9.35 years, male to female ratio of the patients was 0.7:1. Out of 75 patients on FNAC, 50(66.7%) samples were adequate. In this study, a malignant thyroid nodule on FNAC was noted in 21(28%) patients, and a benign thyroid nodule on FNAC was noted in 54(72%) patients. Conclusion: The adequacy of fine needle aspiration cytology for detecting thyroid lesions in patients with thyroid lesions was 66.7%.

Capillary blood sampling for the determination of clozapine concentrations: analytical validation and patient experience.

Patients may be reluctant to start clozapine (CLZ) because of the frequent blood sampling needed for white blood cell monitoring, but also therapeutic drug monitoring of CLZ. Finger prick, instead of venepuncture, might lower the threshold to CLZ use. The aim of this study was to determine whether CLZ concentrations are the same in capillary and venous blood samples. Capillary blood was drawn by finger prick and collected in the Hem-Col tube. Paired capillary and venous blood samples were collected from inpatients and outpatients of a mental health institute. Patients were asked to rate pain, experience, and preference for blood sampling method. Passing-Bablok analysis of 40 paired samples showed that CLZ concentrations were statistically equal in capillary and venous samples {slope 0.96 [95% confidence interval (CI): 0.88-1.04], intercept -6.86 (95% CI: -30.75 to 24.13)}. Venepuncture was the preferred method based on the experience ( P = 0.009) and preference ( P = 0.043) items. In conclusion, CLZ concentrations were similar in venous and capillary blood samples. Venepuncture appeared to be preferred to finger prick for blood sampling. Our results emphasize the importance of consulting patients' individual preference for blood sampling method.

ID22 - the high-resolution powder-diffraction beamline at ESRF.

Following Phase 2 of the upgrade of the ESRF in which the storage ring was replaced by a new low-emittance ring along with many other facility upgrades, the status of ID22, the high-resolution powder-diffraction beamline, is described. The beamline has an in-vacuum undulator as source providing X-rays in the range 6-75 keV. ID22's principle characteristics include very high angular resolution as a result of the highly collimated and monochromatic beam, coupled with a 13-channel Si 111 multi-analyser stage between the sample and a Dectris Eiger2 X 2M-W CdTe pixel detector. The detector's axial resolution allows recorded 2θ values to be automatically corrected for the effects of axial divergence, resulting in narrower and more-symmetric peaks compared with the previous fixed-axial-slit arrangement. The axial acceptance can also be increased with increasing diffraction angle, thus simultaneously improving the statistical quality of high-angle data. A complementary Perkin Elmer XRD1611 medical-imaging detector is available for faster, lower-resolution data, often used at photon energies of 60-70 keV for pair-distribution function analysis, although this is also possible in high-resolution mode by scanning up to 120° 2θ at 35 keV. There are various sample environments, allowing sample temperatures from 4 K to 1600°C, a capillary cell for non-corrosive gas atmospheres in the range 0-100 bar, and a sample-changing robot that can accommodate 75 capillary samples compatible with the temperature range 80 K to 950°C.

Critical Assessment of Phenotyping Cocktails for Clinical Use in an African Context.

Interethnic and interindividual variability in in vivo cytochrome P450 (CYP450)-dependent metabolism and altered drug absorption via expressed transport channels such as P-glycoprotein (P-gp) contribute to the adverse drug reactions, drug-drug interaction and therapeutic failure seen in clinical practice. A cost-effective phenotyping approach could be advantageous in providing real-time information on in vivo phenotypes to assist clinicians with individualized drug therapy, especially in resource-constrained countries such as South Africa. A number of phenotyping cocktails have been developed and the aim of this study was to critically assess the feasibility of their use in a South African context. A literature search on library databases (including AccessMedicine, BMJ, ClinicalKey, MEDLINE (Ovid), PubMed, Scopus and TOXLINE) was limited to in vivo cocktails used in the human population to phenotype phase I metabolism and/or P-gp transport. The study found that the implementation of phenotyping in clinical practice is currently limited by multiple administration routes, the varying availability of probe drugs, therapeutic doses eliciting side effects, the interaction between probe drugs and extensive sampling procedures. Analytical challenges include complicated sample workup or extraction assays and impractical analytical procedures with low detection limits, analyte sensitivity and specificity. It was concluded that a single time point, non-invasive capillary sampling, combined with a low-dose probe drug cocktail, to simultaneously quantify in vivo drug and metabolite concentrations, would enhance the feasibility and cost-effectiveness of routine phenotyping in clinical practice; however, future research is needed to establish whether the quantitative bioanalysis of drugs in a capillary whole-blood matrix correlates with that of the standard plasma/serum matrixes used as a reference in the current clinical environment.

Correction of distorted X-ray absorption spectra collected with capillary sample cell

Correction of distorted X-ray absorption spectra collected with capillary sample cell

Evaluation of dried blood spots as an alternative sampling strategy for 5-fluorouracil monitoring: From method development to clinical application

Therapeutic drug monitoring (TDM) of 5-Fluorouracil (5-FU) is strongly recommended because of its large inter-individual pharmacokinetic variability, narrow therapeutic window, and incidence of toxicity. However, there are several factors that limit the application of TDM in clinical settings. Considering the intrinsic advantages of dried microsamples, such as minimally invasive sampling, analyte stability, and cost-effective logistics, this study aimed to develop a method for the determination of 5-FU in dried blood spots (DBS) using ultra-high liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and to evaluate its clinical application. Sample preparation was based on an aqueous extraction followed by protein precipitation. Separation was performed in an Acquity UPLC® HSS C18 (150 ×2.1 mm, 1.8 µm), and the mobile phases were water and acetonitrile with 0.5% acetic acid. The total run time was 5.5 min. The method was linear from 100 to 2000 ng/mL, precise (maximum CV% of 7.5%), and accurate (98.3–115.4%). The average recovery was 70%. Blood hematocrit had a minimal impact on the assay. DBS samples were stable for 21 days at 4, 25, and 45 °C. A total of 40 paired samples of plasma, capillary DBS, and venous DBS were analyzed. Median 5-FU concentrations were 444.7, 637.0, and 499.7 ng/mL for plasma, capillary DBS, and venous DBS, respectively. Capillary and plasma concentrations were significantly correlated (r > 0.90), but there was a lack of agreement between the methods, as capillary DBS levels were on average 146% of plasma. Venous DBS corresponded to 110% of the measured plasma concentrations, with a strong correlation (r > 0.97) and agreement between the methods. Our study is the first to report the use of DBS samples to quantify 5-FU. Further studies are needed to establish whether capillary samples can replace plasma.

Comparison of mathematically arterialised venous blood gas sampling with arterial, capillary, and venous sampling in adult patients with hypercapnic respiratory failure: a single-centre longitudinal cohort study

BackgroundAccurate arterial blood gas (ABG) analysis is essential in the management of patients with hypercapnic respiratory failure, but repeated sampling requires technical expertise and is painful. Missed sampling is common...

Point of care assay for blood aripiprazole concentrations: development, validation and utility.

The antipsychotic aripiprazole is often used in the treatment of first-episode psychosis. Measuring aripiprazole blood levels provides an objective measure of treatment adherence, but this currently involves taking a venous blood sample and sending to a laboratory for analysis. To detail the development, validation and utility of a new point of care (POC) test for finger-stick capillary blood concentrations of aripiprazole. Analytical performance (sensitivity, precision, recovery and linearity) of the assay were established using spiked whole blood and control samples of varying aripiprazole concentration. Assay validation was performed over a 14-month period starting in July 2021. Eligible patients were asked to provide a finger-stick capillary sample in addition to their usual venous blood sample. Capillary blood samples were tested by the MyCare™ Insite POC analyser, which provided measurement of aripiprazole concentration in 6 min, and the venous blood sample was tested by the standard laboratory method. A total of 101 patients agreed to measurements by the two methods. Venous blood aripiprazole concentrations as assessed by the laboratory method ranged from 17 to 909 ng/mL, and from 1 to 791 ng/mL using POC testing. The correlation coefficient between the two methods (r) was 0.96 and there was minimal bias (slope 0.91, intercept 4 ng/ml). The MyCare Insite POC analyser is sufficiently accurate and reliable for clinical use. The availability of this technology will improve the assessment of adherence to aripiprazole and the optimising of aripiprazole dosing.

Hilab System Device in an Oncological Hospital: A New Clinical Approach for Point of Care CBC Test, Supported by the Internet of Things and Machine Learning.

The complete blood count (CBC) is a highly requested test that is generally restricted to centralized laboratories, which are limited by high cost, being maintenance-demanding, and requiring costly equipment. The Hilab System (HS) is a small, handheld hematological platform that uses microscopy and chromatography techniques, combined with machine learning (ML) and artificial intelligence (AI), to perform a CBC test. This platform uses ML and AI techniques to add higher accuracy and reliability to the results besides allowing for faster reporting. For clinical and flagging capability evaluation of the handheld device, the study analyzed 550 blood samples of patients from a reference institution for oncological diseases. The clinical analysis encompassed the data comparison between the Hilab System and a conventional hematological analyzer (Sysmex XE-2100) for all CBC analytes. The flagging capability study compared the microscopic findings from the Hilab System and the standard blood smear evaluation method. The study also assessed the sample collection source (venous or capillary) influences. The Pearson correlation, Student t-test, Bland-Altman, and Passing-Bablok plot of analytes were calculated and are shown. Data from both methodologies were similar (p > 0.05; r ≥ 0.9 for most parameters) for all CBC analytes and flagging parameters. Venous and capillary samples did not differ statistically (p > 0.05). The study indicates that the Hilab System provides humanized blood collection associated with fast and accurate data, essential features for patient wellbeing and quick physician decision making.