Analysis Of Blood Serum Samples Research Articles

Raman Spectra of Blood Serum as Holistic Biomarker for Differential Auxiliary Diagnoses of Attention Deficit and Hyperactivity Disorder (ADHD) in Adults

Attention deficit and hyperactivity disorder (ADHD) is a prevalent neurodevelopmental condition, impacting approximately 10% of children globally. A significant proportion, around 30–50%, of those diagnosed during childhood continue to manifest ADHD symptoms into adulthood, with 2–5% of adults experiencing the condition. The existing diagnostic framework for ADHD relies on clinical assessments and interviews conducted by healthcare professionals. This diagnostic process is complicated by the disorder’s overlap in symptoms and frequent comorbidities with other neurodevelopmental conditions, particularly bipolar disorder during its manic phase, adding complexity to achieving accurate and timely diagnoses. Despite extensive efforts to identify reliable biomarkers that could enhance the clinical diagnosis, this objective remains elusive. In this study, Raman spectroscopy, combined with multivariate statistical methods, was employed to construct a model based on the analysis of blood serum samples. The developed partial least-squares discriminant analysis (PLS-DA) model demonstrated an ability to differentiate between individuals with ADHD, healthy individuals, and those diagnosed with bipolar disorder in the manic phase, with a total accuracy of 97.4%. The innovative approach in this model involves utilizing the entire Raman spectrum, within the 450–1720 cm−1 range, as a comprehensive representation of the biochemical blood serum setting, thus serving as a holistic spectroscopic biomarker. This method circumvents the necessity to pinpoint specific chemical substances associated with the disorders, eliminating the reliance on specific molecular biomarkers. Moreover, the developed model relies on a sensitive and reliable technique that is cost-effective and rapid, presenting itself as a promising complementary diagnostic tool for clinical settings. The potential for Raman spectroscopy to contribute to the diagnostic process suggests a step forward in addressing the challenges associated with accurately identifying and distinguishing ADHD from other related conditions.

Paraoxonase, haptoglobin, serum amyloid A, tumor necrosis factor and acetylcholinesterase levels in ewes with pregnancy toxemia

Objective: In this study were investigated serum paraoxonase, haptoglobin, tumor necrosis factor-α, acetylcholinesterase, serum amyloid A, beta-hydroxybutyric acid, nonesterified fatty acids, glucose, total protein, aspartate aminotransferase, gamma-glutamyl transferase, cholesterol and triglyceride in ewes with pregnancy toxemia Materials and Methods: This study consisted of 10 control and 10 groups with pregnancy toxemia, comprising 20 merino hybrid ewes aged between 2-6 years. Results: The analysis of blood serum samples revealed that serum amyloid A (SAA), haptoglobin (HPT), tumor necrosis factor-α (TNF), paraoxonase (PON1), acetylcholinesterase (ACHE), aspartate aminotransferase (AST), gamma-glutamyl transferaz (GGT) and cholesterol did not differ statistically significant between two groups although SAA, HPT, TNF, PON1, ACHE, AST, GGT levels were higher in ewes with pregnancy toxemia when compared to healthy ewes. Beta hydroxybutyric acid (BHBA) and nonesterified fatty acids (NEFA) (P<0.001), triglyceride, and total protein (P<0.01) increased that glucose (P<0.001) levels decreased in sheep with pregnancy toxemia compared with healthy ewes. Conclusion: Acetylcholinesterase, paraoxonase, haptoglobin, tumor necrosis factor-α, serum amyloid A concentration researched may prove beneficial laboratory findings diseases in sheep with pregnancy toxemia.

Heavy Metals in Blood Serum of Smokers and Non-smoking Controls

Background:: Background Method:: In this study, performed in Al-Najaf during 2023, concentrations of three heavy metals - cadmium (Cd), chromium (Cr), and lead (Pb) – were investigated in two groups: cigarette smokers, and non-smokers (the control group) by using atomic absorption spectrophotometry (AAS). Participants in this experiment were categorized into five age groups: 21-30, 31-40, 41-50, 51-60, and 61- 70. Results:: The results showed that smokers displayed significantly higher blood serum concentrations of all heavy metals (Cd, Cr, and Pb) compared to non-smokers Furthermore, it is found that the mean concentrations of Cd, Cr, and Pb for smokers were 0.873±0.619 ppm, 1.957±0.883 ppm, and 0.043±0.021 ppm, respectively. For non-smokers, they were 0.197±0.165 ppm, 0.159±0.105 ppm, and 0.031±0.016 ppm, respectively. These differences were statistically significant. Overall, the mean heavy metal levels displayed a descending order in the present study, i.e. Cd > Cr > Pb." Conclusion:: The concentrations of Cd and Cr in all samples of the present study were higher than the biological limit according to ACGIH. Therefore, Cd and Cr were the most critical metals accumulated in the blood of cigarette smokers. Additionally, the findings have indicated that the analysis of blood serum samples can serve as a reliable indicator for establishing the association between cigarette smoking and the presence of heavy metals.

Serum Anti-Helicobacter pylori IGG Antibody Test Among Patients with Diabetes: A Cross-Sectional Study

Diabetes patients frequently experience numerous and serious chronic infections because of their weakened cellular and humoral immune systems. Regrettably, there is insufficient information on the prevalence of Helicobacter pylori (H. pylori) infection among diabetics, especially in southern Libya. This study aimed to determine how frequently these bacteria were infected among diabetes patients in various parts of Ubari. This study was conducted on 150 diabetic patients of both sexes, who visited the health centers in different Ubari areas. Their ages ranged from 20 to 80. Analysis of blood serum samples to measure Helicobacter pylori IgG antibodies by the enzymatic immunoassay (ELISA) and the rapid test (cassette rapid test). Biochemistry parameters such as Blood glucose concentration, cumulative glucose, ?-amylase, LDH, Serum cholesterol, Triglycerides, LDL, and HDL, as well as the blood group, were also measured. Other data collected was the body mass index. A questionnaire was used to find out some habits, such as smoking, the use of spices in food, and the type and duration of diabetes. Data showed the rate of infection with H. pylori bacteria through immunological testing was 45.33% in both sexes; however, it was significantly higher in males than females, 28% and 17%, respectively. The infection rate was found to be higher in the age group 41–60 years, and there was no significant difference in bacterial infection between patients with type I and type II diabetes (20.7 and 24.7%), respectively. Similarly, there was no effect of body mass index on the rate of infection.

Epizootological and epidemiological aspects of leptospirosis in Ukraine for the period 2003–2022

Zoonotic leptospirosis is an infectious disease caused by pathogenic Leptospira bacteria that can be transmitted from animals to humans. Animals, especially wild and domestic mammals, are reservoir hosts that carry and excrete the bacteria in their urine. A retrospective analysis of the incidence of leptospirosis in animals and humans in Ukraine from 2003 to 2022 was conducted based on reports from regional state laboratories of veterinary medicine and the Center for Public Health. GIS mapping was used to analyze and visualize the data. The incidence and prevalence of leptospirosis among different animal species, including farm, domestic and wild animals, were analyzed. These studies included a retrospective analysis of blood serum samples from different animal species for leptospirosis and analysis of the results to determine the level of seropositivity. The study analyzed a total of 6,543,934 samples, with an overall seropositivity rate of 3.3%. Among cattle, 4.1% of the samples were positive. For pigs, 2.1% were positive. Horses had a seropositivity rate of 7.9%, while dogs and cats had seropositivity rates of 17.5% and 13.1% respectively. Wild boars showed a positivity rate of 2.2%. The number of seropositive animals of different species in Ukraine showed different dynamics from 2003 to 2022. The highest number of positive cases was found among cattle, pigs and horses. However, the number of positive cases decreased significantly after 2015, which coincides with a significant reduction in the number of farm animals. Trends of increasing seropositivity among dogs and cats in the period 2007–2015 indicate that these species are also active carriers of Leptospira, as are the leading agricultural species. Wildlife species with stable seropositivity serve as both sources and reservoirs of Leptospira. Wild pigs are becoming the main bacterial carriers in all regions of Ukraine. There is a marked disproportion between the number of positive cases among farm animals and wildlife, indicating that seropositivity in these populations exists largely autonomously. A total of 7,937 people were infected in Ukraine between 2003 and 2022. Certain regions, such as Lviv, Kherson, Kyiv, Mykolaiv, and Vinnytsia, account for a larger share of the total number of cases, ranging from 4.8% to 7.3%. The incidence of human leptospirosis has fluctuated over the years, peaking at 473 cases in 2014, followed by a decline: 301 cases in 2015, 323 cases in 2016 and 330 cases in 2017, and in subsequent years the number of cases remained relatively stable, ranging from 142 to 295 cases per year. The study emphasizes the need to improve preventive measures and raise public awareness of the disease, especially in rural areas. It is important to adopt a comprehensive interdisciplinary approach involving collaboration between veterinary medicine, public health and environmental authorities to better understand and address the complexities of leptospirosis transmission and reduce its impact on animal and human health.

SERUM CYSTATIN C AS A PREDICTOR OF THE DEVELOPMENT OF ACUTE KIDNEY INJURY IN NEWBORNS WITH HYPOXIC- ISCHEMIC ENCEPHALOPATHY SUBMITTED TO THERAPEUTIC COOLING

Assessment of renal function in newborns is extremely important and at the same time challenging due to the unique body structure, increased vulnerability and rapid growth of the latter. However, for the early detection of acute kidney injury (АКI), rational dosing of drugs and safe drug therapy, the identification of early markers of renal dysfunction is essential.The objective is to evaluate the prognostic value of serum biomarkers for the early diagnosis of АКI in newborns with hypoxic-ischemic encephalopathy against the background of therapeutic hypothermia and preventive use of methylxanthines.Materials and Methods. A single-center, prospective, randomized trial involving 44 neonates with АКI requiring therapeutic hypothermia and prophylactically receiving caffeine citrate or theophylline to prevent АКI progression was conducted in from 2019 to 2022 on the basis of the NICU of Zaporizhzhia Regional Clinical Children's Hospital.Laboratory analysis of blood serum samples was performed on day 1, day 3 and 5 from birth, creatinine (Cr) and cystatin C (CysC) levels and their associations with the development of АКI were determined according to the neonatal criteria of the 2012 KDIGO guideline.Statistical analysis was performed using Statistica 13.0 program, TIBCO Software Inc. (license number JPZ804I382130ARCN10-J) and Microsoft Excel 2013 (license number 00331-10000-00001-АА404). The probability of the difference in absolute values of mean values was determined using non-parametric methods of statistical analysis: the Mann-Whitney U-Test for unrelated groups and the Wilcoxon signed-rank t test for related groups. Statistical significance was defined as p < 0.0500.The study was performed in accordance with the moral and ethical standards established by the IGH / GCP guidelines, the World Medical Association Helsinki Declaration, adopted in 1964 and amended in 1975, 1983, 1989, 1996 and 2000, The European Convention of Human Rights and Biomedicine and the legislation of Ukraine. The protocol was approved by the Medical Ethics Commission at Zaporizhzhia State Medical University. The study was performed as part of the research project "Optimization of diagnostics and intensive care of polyetiologic lesions of the brain, gastrointestinal tract, and kidneys in newborns and older children" (State registration number O118U007142) of the Pediatric Surgery and Anesthesiology Department of the State Institution "Zaporizhzhia State Medical University of the Ministry of Health of Ukraine."Results and their discussion. In general, AKI according to KDIGO developed in 5.00 (11.36 %) neonates out of 44.00 (100.00 %), stage 0 was found in 39.00 (88.64 %). 4.00 (9.09%) newborns had stage I, and 1 (2.27%) developed stage II; the data obtained were similar: p = 0.7872; U = 230.00. None of the patients progressed to stage III.In the newborns with preserved renal function during the study there was a decrease in Cr and a predictable, by this marker, increase in GFR. A statistically significant increase in Cr level and decrease in GFR was found in the newborns with renal dysfunction on days 3 and 5 of the study. Cr level progressed from baseline 1.07 (0.87; 1.10) mg/dl to 1.13 (0.86; 1.25) mg/dl on day 3 and to 1.40 (1.15; 1.82) mg/dl on day 5, while GFR decreased from 19.76 (19.07; 22.90) ml/min/1.73m2 to 17.97 (13.84; 24.42) ml/min/1.73m2 on day 3 and was 12.38 (11.12; 17.54) ml/min/1.73m2 on day 5, with p < 0.0500.CysC progressively decreased in the neonates without AKI from 2.50 (2.20; 2.60) ng/ml to 2.25 (2.08; 2.49) ng/ml, p = 0.0095; while in the neonates with AKI the level of this marker did not change and was 2.56 (2.41; 2.70) ng/ml on day 1 and 2.42 (1.89; 2.45) ng/ml on day 5, p = 0.2963. As this marker changed, eGFR (CysC) increased progressively in the cohort of patients without kidney damage but did not change in the other group.The diuresis rates in the newborns of both groups did not differ, being ≥ 1.5 ml/kg/h, which is probably due to methylxanthine therapies, p ≥ 0.0500.Conclusions. CysC assessment did not provide additional information on the development of acute kidney injury in neonates (nAKI) in the first 5 days of life, which would have allowed a quick decision to change the intensive care program. Further studies involving newborns who did not receive prophylactic therapy are needed.

Non-targeted Serum Metabolomics Identifies Candidate Biomarkers Panels Associated with Nonalcoholic Fatty Liver Disease: A Pilot Study in Russian Male Patients

Aims: The aim of the present study was to explore changes in the serum metabolome of patients with NAFLD relative to healthy controls to identify biomarkers associated with steatosis or Non-Alcoholic Steatohepatitis (NASH). Background: The serum metabolome reflects changes at the organismal level. This is especially important in Non-Alcoholic Liver Disease (NAFLD), where changes in hormones, cytokines, enzymes and other metabolic alterations can affect the liver, as well as adipose tissue, skeletal muscle and other systems. Objective: The objectives were to conduct non-targeted serum metabolomics, data processing, and identification of candidate biomarkers, as well as panels and assessment of their prognostic value. Materials and Methods: Non-targeted metabolomic analysis of blood serum samples from 21 male patients with NAFLD (simple steatosis or NASH) and seven male Control group was performed using gas chromatography-mass spectrometry. Results: A total of 319 serum metabolites were detected in NAFLD and Control groups, several of which differed significantly between groups. The most discriminating biomarkers were 3-hydroxybutyric acid, 2-hydroxybutyric acid, 2,3-dihydroxybutyric acid, arabitol and 3-methyl-2-oxovaleric acid. Using a panel of three, four or more markers could distinguish patients with NAFLD from controls, and patients with NASH from those with simple steatosis. Conclusion: We identified candidate biomarkers for simple steatosis and NASH. Since NAFLD is a multifactorial disease, it is preferable to use a marker panel rather than individual metabolites. Markers may not only result from dysregulation of metabolic pathways in patients with NAFLD, they may also reflect adaptive responses to disease, including functional changes in the intestinal microbiota.

Detection of biogenic polyamines in blood of patients with breast cancer

The main threat of cancer diseases is their spreading throughout the population of many countries of the world and the complexity of their diagnostics at the early stages. Because of that, search and development of the latest diagnostic methods for oncological diseases which would allow them to be diagnosed more precisely and rapidly is going on. The objective of the study was developing a method for qualitative and quantitative analysis of polyamines as potential tumour markers in blood serum of patients with breast cancer using a newly created immune biosensor based on the effect of surface plasmon resonance (SPR). In the process of the study we used basics of immune analysis, methods of biosensor analysis with preliminary modification of biosensor analytical surface with certain reagents, such as protein A and BSA, for better orientation of the sensitive layer made from antibodies. During the study 30 samples of blood serum were analyzed, 21 of which were obtained from the patients with breast cancer and 9 samples were normal, taken from healthy people and used as controls. Analysis of blood serum samples was made, using previously created calibration curve, based on polyamine solutions in concentrations from 5 ng/mL to 1 µg/mL. It allowed determination of the presence of polyamines in blood samples and approximate concentration of polyamines comparing resonance angle shift in calibration curve and blood samples. According to the obtained results, the concentration of polyamines exceeded their physiological levels and was in the range of 21.3–125.1 ng/mL. The proposed approach allows one to determine the presence and approximate concentrations of polyamines in range from 5 ng/mL to 1 µg/mL in samples of blood serum of patients with breast cancer which correlates with tumour size and the age of the patients.

Screening of SRLV in herds in mid-Eastern Poland

The aim of the study was to evaluate the epidemiological condition of SRLV infections in nucleus flocks of sheep. The surveillance of Lentivirus infections was conducted in sheep flocks from the mid-Eastern part of Poland: the area of Lubelskie, Świętokrzyskie and Podkarpacie provinces. Ninety eight flocks were chosen for a detailed analysis. They included 6,470 mother ewes belonging to 15 breeds and lines: Polish Merino sheep, Polish Lowland sheep, Wielkopolska sheep, Żelaźnieńska sheep, Uhruska sheep, Olkuska sheep, Polish Heath sheep, Świniarka sheep, Polish Pogorze sheep, Podhale Zackel sheep, Black-headed sheep, Ile de France, Berrichon du Cher, BCP and SCP. The identification of the infected animals and the assessment of the epidemiological condition of the flocks was carried out using a serological analysis of blood serum samples. The assay of MVV-specific antibodies in blood serum was performed using the ELISA test. The results obtained showed that the highest rate of flocks with at least one animal with a positive serological response was in the Podkarpacie Province (71.43%), and the lowest rate (27.03%) was observed in Lubelskie Province. The analysis of the rate of the sheep infected with SRLV indicated that the greatest number of seropositive animals was highest in Podkarpackie Province (19.9%), which corresponds to the results for the flocks, and was significantly higher (p ≤ 0.01) than in Świętokrzyskie Province (11.35%) and Lubelskie Province (9.20%). The flock size turned out to be a factor which significantly influenced the prevalence of SRLV infections. The prevalence was highest (13.6%) in the flocks exceeding 100 sheep, and decreased together with the decreasing number of heads in the flock. It must be stressed that the problem of SRLV infections is very complex and depends on many factors. Therefore it is necessary to carry out a detailed diagnosis of the factors leading to expansion of the virus in sheep flocks before developing flock protection programs...

Allergen-specific IgE and IgG4 patterns among patients with different allergic diseases

Background In addition to allergen-specific IgE (sIgE), allergen-specific IgG4 (sIgG4) antibodies are also involved in the immune response resulting from an allergen exposure. The aim of our study was to analyze sIgE and sIgG4 patterns in the most common allergic disorders: bronchial asthma, upper airway disorders and atopic dermatitis.Methods In this study a screening analysis of blood serum samples from 673 patients aged from 6 months to 17 years with different allergic entities was performed on microarrays. sIgE and sIgG4 levels to the most common allergens were estimated.Results sIgE response to most pollen allergens is more strongly associated with respiratory diseases than with atopic dermatitis, while sIgE responses to cat and dog dander are more strongly associated with bronchial asthma than with atopic dermatitis and upper airway disorders such as rhinosinusitis and allergic rhinitis. A lower prevalence of sIgG4 to pollen allergens in cases of atopic dermatitis is observed compared with that in cases of asthma and upper airway disorders. Analyzing all the allergic disorders, one can see that sIgG4 response to inhalant allergens is strongly associated with sensitization to the corresponding allergen.Conclusion Allergen-specific IgE and IgG4 patterns that are relevant to concrete allergic diseases differ by sIgE and sIgG4 prevalences to defined allergens.

Prevalence of CAEV infections in goat herds

The aim of the study was to analyze the occurrence of caprine arthritis encephalitis virus (CAEV) in white improved goats, colored improved goats, Saanen goats, Alpine goats and Boer goats, raised in three regions of Poland. The analysis of CAEV infection levels was carried out in goat herds from the provinces in mid-Eastern Poland. The analysis included four goat herds. In total, they encompassed 251 herds of the following breeds: white improved goat, colored improved goat, Saanen goat, Alpine goat and Boer goat. The identification of the infected animals and the assessment of the epidemiological condition of the herds was carried out using serological analysis of blood serum samples. The assay of CAEV-specific antibodies in blood serum was performed using ELISA test. As a result of the observations it was established that with regards to the provinces, the prevalence level ranged from 35.40% in Mazowieckie province to 81.10% in Lubelskie province, and the average infection rate of animals in the studied region was 51.60%. As far as the breeds are concerned, it was found that the observed infection rate of the Saanen goat population was significantly higher (p ≤ 0.05) than the rates for improved white goat (48.90%) and Alpine goat (50.00%). In relation to the colored improved goat, the calculated statistical difference was greater (p ≤ 0.01), and the percentage of infected animals was 32.10%. The analysis of the infection rate in the Boer goat herd revealed that 66.70% of animals are seropositive, and the statistical analysis did not show any significant differences in prevalence compared to other studied breeds. To sum up, it should be noted that the improvement of the situation may be attributed to consistent examination of goats and development of CAEV-elimination programs for herds. When creating programs aimed at the elimination of the virus it is also important to remember to raise the awareness of the farmers with regards to the detrimental effect of CAEV infections..

Iron isotopic composition of blood serum in anemia of chronic kidney disease.

Chronic kidney disease (CKD) is a general term for disorders that affect the structure and function of the kidneys. Iron deficiency (ID) and anemia occur in the vast majority of CKD patients, most of whom are elderly. However, establishing the cause of anemia in CKD, and therefore making an informed decision concerning the corresponding therapeutic treatment, is still a challenge. High-precision Fe isotopic analysis of blood serum samples of CKD patients with and without ID/anemia was performed via multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS) for such a purpose. Patients with CKD and/or iron disorders showed a heavier serum Fe isotopic composition than controls. Many clinical parameters used for the diagnosis and follow-up of anemia correlated significantly with the serum Fe isotopic composition. In contrast, no relation was observed between the serum Fe isotopic composition and the estimated glomerular filtration rate as a measure of kidney function. Among the CKD patients, the serum Fe isotopic composition was substantially heavier in the occurrence of ID anemia, while erythropoietin-related anemia did not exert this effect. The Fe isotopic composition can thus be useful for distinguishing these different types of anemias in CKD patients, i.e. ID anemia vs. erythropoietin-related anemia.

The complex evaluation of lipid metabolism and blood coagulation system indicators for prediction and early diagnosis of the preeclampsia

Aim. To study informative and prognostic significance of lipid metabolism markers and coagulation system condition for PE early diagnostics in pregnant women during the second gestational trimester with risk evaluation of cardiovascular and metabolic pathologies in the given women category.Materials and methods. The analysis of blood serum samples in 267 pregnant women in II gestational trimester was carried out. The total cholesterol was determined by colorimetric method, enzymatic with CHOD/PAP, TG – by enzymatic colorimetric method, HDL – by homogeneous method, LDL – by direct method. VLDL concentration was calculated according to Fridvald's formula: VLDL = TG/2.2. AF was calculated according to the formula: AF = (TC-HDL-c)/HDL-c. Pregnant women in II and III gestational trimesters also were examined concerning the general assessment of coagulation system condition – the concentration in blood plasma of D-dimer, soluble fibrin (SFMC), fibrinogen, FIPF, protein C activity, AT III, blood plasma clotting time was determined by PT test.Results. Of the 267 pregnant women, in 43 (16.1 %) of them, which formed the main group for research, the development of PE was found. Those pregnant women, who had PE clinical picture of the different severity levels, from the second trimester had significantly elevated TG, VLDL, AF levels, and low level of HDL in blood serum with high concentration of D-dimer (from 80 to 713 ng/ml), as well as protein C low activity in 17.6 % of pregnant women. In the third trimester pregnant women, having PE, fibrinogen content was significantly higher (4.4±1.02); the accumulation of a significant amount of SF, accompanied by FIPF presence in 40 % of pregnant women, was found in 50 % of pregnant women; a significant reducing (˂70 %) of the protein C activity was found in 48 % of patients.Conclusion. Both significant increasing of the soluble fibrin in blood plasma, and reducing of the protein C activity below 70 % are thrombosis prognostic indexes. The control of lipid metabolism and coagulation system indexes is necessary during all stages of pregnancy for estimation of PE risk and cardiovascular,cerebral vascular and metabolic complications prevention

RETRACTED: An imprinted Ag@CdS core shell nanoparticle based optical-electrochemical dual probe for trace level recognition of ferritin

In this work, we present a new approach to prepare the Ag@CdS core-shell fluorescent nanoparticles wrapped with molecularly imprinted polymer for ferritin macromolecule by capping with vinyl derivative of cysteine. The imprinted Ag@CdS nanoparticle was prepared via activator regenerated by electron transfer-atom transfer radical polymerization (ARGET-ATRP) method onto the surface of vinyl silane modified pencil graphite electrode. Combination of Ag and CdS in a single motif causes the dual behavior of core shell nanoparticle, which shows enhanced fluorescence as well as electrochemical properties. The performance of the obtained imprinted sensor was investigated by cyclic voltammetry, electrochemical impedance spectroscopy, chronocoulometry, differential pulse voltammetry and fluorescence spectrophotometry. Under the optimal experimental conditions, the current response of the electrochemical sensor was linear to ferritin concentrations in the range from 1.99 to 23.43 µg L⁻¹, with the detection limit of 0.65 µg L⁻¹. Similarly, a linear response was obtained between fluorescence quenching of imprinted Ag@CdS and concentration of ferritin in the range from 4.0 to 91.0 µg L⁻¹, with limit of detection (LOD) of 1.3 µg L⁻¹. The method was successfully applied to the analysis of blood serum samples of five different men and women with acceptable recoveries of 99.7% and 100.3% (RSD in %=1.0-2.0).

Application of potentiometric biosensor based on recombinant urease for urea determination in blood serum and hemodialyzate

Potentiometric biosensor based on two identical pH-sensitive field-effect transistors for urea determination was developed. Recombinant urease with low affinity to urea (Km=200mM) was immobilized via entrapment in PVA/SbQ photopolymer on one transistor and served as a biorecognition element of the biosensor, while bovine serum albumin in PVA/SbQ photopolymer placed on the second transistor was used for reference. Biosensor was characterized by a wide range of urea determination: 0.5–15mM linear range (operational detection range – 0.5–40mM) and quick response time (1–2min). Samples of blood serum and hemodialysate without urea caused no biosensor response. All this allowed analysis of blood serum samples that were diluted 10 times, what led to smaller measurement error in comparison with 100–500 times dilution in case of biosensors based on non-modified urease from soy beans. Urea concentrations in 10 samples of serum were determined; biosensor results correlated well with two control methods of urea measurement. Furthermore, kinetics of decreasing urea concentration in dialysate during hemodialysis was demonstrated. Biosensor measurements of dialysate samples were verified by traditional colorimetric determination of urea. Proposed biosensor can be effectively used for analysis of samples with different concentrations of urea and for hemodialysis control. What is more, characteristics of the biosensor make possible real-time measurements of urea concentration during hemodialysis by pumping dialysis fluid through the working cell. Biosensor showed no significant decrease of responses during 5 month of storage.

Application of enzyme/zeolite sensor for urea analysis in serum

Urea biosensor based on zeolite-adsorbed urease was applied for analysis of blood serum samples. It should be noted, that this biosensor has a number of advantages, such as simple and fast performance, the absence of toxic compounds during biosensor preparation, high reproducibility and repeatability (RSD=9% and 4%, respectively). The linear range of urea determination by using the biosensor was 0.003–0.75mM, and the limit of urea detection was 3μM. The method of standard addition was used for analysis of serum samples with 500-fold dilution. Total time of analysis was 10min. Good reproducibility of urea determination in real samples was demonstrated (RSD=10%). Biosensor results were verified by using a common method of urea determination (diacetyl monoxime reaction). It was shown that by using this biosensor distinguishing healthy people from people with renal dysfunction becomes easier.

Trace elemental analysis of blood serum samples of patients afflicted with parkinson’s disease

Trace elemental analysis was carried out in the blood samples of patients afflicted with Parkinson’s disease and controls using ICP-MS technique. 23 elements over a wide Z range from Li to Pb were detected and their concentrations determined. These concentrations levels are analyzed to find a possible correlation between the levels of some of these trace elements in the diseased and the pathology of the disease.

Determination of antibodies to Yersinia enterocolitica bacteria using a piezoelectric quartz crystal immunosensor

A gravimetric technique is proposed for the determination of antibodies to Yersinia enterocolitica serovar O: 3 using a piezoelectric quartz crystal immunosensor based on immobilized lipopolysaccharides. Conditions are optimized and a procedure is developed for the flow-injection analysis of blood serum samples using the immunosensor as the detector. The detection limit for antibodies is found to be 1.3 μg/mL, RSD is 8%, and the analytical range is 3–100 μg/mL. The rapidity (the duration of analysis was no longer than 10 min) and the direct detection of the formed agglutinate without additional labeling are the advantages of the proposed technique.

PIXE ANALYSIS OF Ca AND P IN THE DOWNER COW SYNDROME

The aim of this work is the microelemental analysis of blood serum samples collected from healthy and ill cows (downer cow syndrome (DCS)). Today the origin of DCS is uncertain. At the beginning of our work, we assume some connections among the diminution of some nutritive elements from food, the activity of some enzymes and the origin of DCS. The samples were collected from cows at some animal farms on the neighbourhood of Targoviste city. To obtain a microelemental monitoring of these samples, we used a nuclear analysis method PIXE (Particle Induced X-Rays Emission) and a spectrometric one ICP (Induced Coupled Plasma). For Ca and P content of the analysed samples, we used PIXE based on the internal standard method. The ICP analysis method was used for Mg content determination. The determinations of phosphatase alkaline enzyme of analysed blood serum samples were made by a spectrometric analysis using Bessey-Lowry method. In studying diseases a significant variation in Ca, P, Mg and enzyme contents was observed. Those changes correlate with age, season of alimentation and type of disease.

Biomedical applications of energy dispersive X-ray fluorescence

An X-ray fluorescence method for in vitro analysis of trace elements in biological samples is presented. The method is characterised by the use of an X-ray tube with secondary targets as a monoenergetic radiation source, and by thin specimens. The method has been applied to the analysis of blood serum samples, gunshot residue and urinary calculi.