Measurement Of Uric Acid Research Articles

P003 ASSOCIATION BETWEEN SERUM URIC ACID AND BLOOD PRESSURE IN BOYS, GIRLS AND ADOLESCENTS WITH OVERWEIGHT and OBESITY ATTENDED IN PEDIATRIC HOSPITALS IN THE AUTONOMOUS CITY OF BUENOS AIRES. “MULTICENTRIC STUDY

Introduction: Childhood overweight and obesity are modifiable risk factors for the development of Hypertension (HTN). Elevated serum uric acid (UA) is a known cardiovascular risk factor in adults. Objective: To evaluate whether there is an association between high serum UA values and elevated BP in overweight and obese children and adolescents. Methods: Multicenter prospective cross-sectional study. Overweight and obese patients aged 5 to 18 years attended in HTN outpatient clinics of three tertiary pediatric hospitals in Buenos Aires were included. Office BP control, 24-hours ambulatory BP monitoring (ABPM) and laboratory tests (metabolic and lipid profile and serum UA measurement) were performed. Results: 173 patients were enrolled, mean age 11.7±2.9 years, 63 women (36.4%), 50 were overweight (28.9%) and 123 obese (71.1%). 143 normotensive (NT) patients were registered, 14 with white-coat HTN, 11 with masked hypertension (MH) and 5 with sustained HTN. The mean value of serum UA was 5.1±1.2, 113 subjects were above the mean value and 24 were above 2SD. Taking serum UA higher than the average (n:113) according to BP we observed 89/143 in NT vs. 13/14 in white-coat HTN (OR 7.8 95% CI 1.1-62.1 p=0.04), 89/143 in NT vs. 8/11 in MH (OR 1.6 95% CI 0.4-6.3 p=0.7) and 89/143 in NT vs. 3/5 in sustained HTN (OR 0.9 95% CI 0.1-5.2 p=0.9). Using serum UA >2SD (n:24) 14/143 above this value in NT vs. 7/14 in white-coat HTN (OR 9.2 95% CI 2.8-30.1 p<0.001), 14/143 in NT vs. 3/11 MH (OR 3.4 95% CI 0.8-14.5 p=0.1) and no subject with sustained HTN had serum UA values >2SD. Conclusions: Elevated serum UA was observed in subjects with white-coat HTN. The number of subjects with sustained HTN was not sufficient to evaluate the association with serum UA values. These findings emphasize the importance of the systematic implementation of 24-hours ABPM for detection of white-coat HTN in overweight and obese children and adolescents.

LACK OF AGREEMENT BETWEEN A POINT-OF-CARE BLOOD URIC ACID METER AND A BENCHTOP CHEMISTRY ANALYZER IN EASTERN BOX TURTLES (TERRAPENE CAROLINA CAROLINA).

Uric acid (UA) is excreted as an end product of protein metabolism in many reptiles, including some chelonians. Elevated plasma UA concentrations can occur due to many physiologic and pathologic changes, and determining plasma UA concentrations is part of a complete general health assessment in this taxon. UA concentrations are typically measured using benchtop chemistry analyzers, but point-of-care (POC) UA meters have also been developed for human use. However, these POC UA meters have not been investigated for use in any reptile species. The purpose of this study was to assess agreement between UA measurements produced by a standard benchtop chemistry analyzer and a POC UA meter in free-living eastern box turtles (Terrapene carolina carolina). UA concentrations were measured with a POC meter using fresh whole blood and frozen-thawed plasma and with a standard benchtop chemistry analyzer using frozen-thawed plasma. Poor-to-moderate agreement was present between each of the three methods as evidenced by mixed models, Passing-Bablok regression, Bland-Altman plots, and Cohen's κ. Differences between methods fell outside of clinically acceptable limits, indicating that the POC UA meter should not be used in eastern box turtles.

Simultaneous Measurement of Uric Acid, Guanine, and Adenine Using AgNP@Mn-MOFs Composite-Based Electrochemical Sensor at Trace Level: Application to Blood, Urine, and DNA Sample Matrices

Simultaneous Measurement of Uric Acid, Guanine, and Adenine Using AgNP@Mn-MOFs Composite-Based Electrochemical Sensor at Trace Level: Application to Blood, Urine, and DNA Sample Matrices

Salivary uric acid dynamics are associated with stress response hormones among African Americans in an urban sample

Acute physiological responses to psychosocial stressors are a potential pathway underlying racial disparities in stress-related illnesses. Uric acid (UA) is a potent antioxidant that has been linked to disparities in stress-related illnesses, and recent research has shown that UA is responsive to acute social stress. However, an examination of the relationships between the purinergic system and other commonly measured stress systems is lacking. Here, we measure and characterize associations of salivary uric acid (sUA) with markers of hypothalamic-pituitary-adrenal (HPA) axis activation, sympathetic-adreno-medullar (SAM) axis activation, and acute inflammation. A community sample of 103 African Americans (33 male, 70 female) completed the Trier Social Stress Test to induce social-evaluative threat. Passive drool collected before, during, and after the stressor task provided salivary reactivity measures of UA (sUA), cortisol, dehydroepiandrosterone sulfate (DHEAS), salivary alpha amylase (sAA – a surrogate marker of SAM activity) and C-reactive protein (sCRP). Multiple regressions revealed that total activation of cortisol, DHEAS, and sCRP were each positively associated with higher total activation of sUA. Additionally, DHEAS reactivity was positively associated with sUA reactivity. Relationships between HPA-axis markers and sUA were especially observed among younger and male participants. Overall, findings suggest potential coordination of stress systems with sUA in response to acute stress, which may further the contributions of biological stress processes to racial health disparities.

Investigating the Expression of miR 203a 3p and Its Role in Inflammatory Response in Severe Preeclampsia of Iraqi women Patients – A Comparative Study

Abstract Background: Preeclampsia (PE) has long been a feared condition impacting women and their pregnancies. Researchers have recently discovered the role of miR203a-p3 in various diseases. The aim of the study was to explore the role of miR203a and measure its levels in pregnant patients, along with reviewing the advancement of inflammatory markers related to disease. Methods: Seventy serum samples and erythrocyte sedimentation rate (ESR) tubes were collected from pregnant women aged 25–33 who were diagnosed with serious PE. Upon this, 15 samples were chosen for testing of the deemed levels and gene expression of miR203a. Laboratory evaluation was mainstreamed in the study, including measurements of serum creatinine, blood urea, and uric acid. These parameters were quantitated using turbidity techniques and coulometric methods for C-reactive protein. In addition, we appraised the ESR uptake by the time method and examined fibrinogen by the agglutination time method. We quantified interleukin-6 (IL-6) using an enzyme-linked immunosorbent assay. Results: The serum levels of biomarkers and inflammatory tests differed significantly in the patients compared to controls. Similarly, a rise in gene expression resulted in an abatement in the level of miR203-p3, and there was a positive direct correlation between them. Conclusion: Patients exhibit high levels of biomarkers and IL-6, along with reduced concentration and expression of miR203a. There is a significant positive correlation between miR203a and disease. Finally, miR203 has played an active role in the current disease.

Efficient and environmentally friendly uric acid voltametric sensor based on Ni-MOF and carboxylated multi-walled carbon nanotubes nanocomposites

Uric acid (UA) levels are significant in the monitoring of human health, making their detection very important. In this paper, a simple and innovative electrochemical method for the detecting UA was established, using a sensing platform based on hybrid electrodes of Nickel-Metal Organic Framework (Ni-MOF) and carboxylated multi-walled carbon nanotubes (MWCNTs-COOH). Detailed investigations into the electrocatalytic activity of Ni-MOF/MWCNTs-COOH/GCE for The Ni-MOF/MWCNTs-COOH exhibited remarkable catalytic activity for UA oxidation. The detection limit was 0.005 μM, with a sensitivity calculation result of 6.377 µA µM−1, and a wide linearity interval (0.03–10 μM, 10–300 μM). Utilizing its high sensitivity and selectivity, this sensor was used for the measurement of UA in biological fluids, including human serum and urine samples, recovery amounts being 96.6–100.8 %, and 98.9–101.3 %. This work is highly significant; offering new perspectives for the application of Ni-MOF based chemical sensors in the realms of environmental monitoring and healthcare.

The alleviatory effects of koumine on MSU-induced gouty arthritis via the TLR4/NF-κB/NLRP3 pathway.

The aim of this study was to validate the preventive effects of koumine (KM), a monoterpene indole alkaloid, on gouty arthritis (GA) and to explore its possible mechanisms. C57BL/6 mice were intraperitoneally administered KM (0.8, 2.4 or 7.2mg/kg), colchicine (3.0mg/kg) or sterile saline. One hour later, a monosodium urate (MSU) suspension was injected into the right hind paws of the mice to establish an acute gout model. Inflammation symptoms were evaluated at 0, 3, 6, 12 and 24 h, and the mechanical withdrawal threshold was evaluated at 0, 6 and 24 h. After 24 h, the mice were euthanized, and the joint tissue, kidney and blood were collected for subsequent experiments. Histological examination and antioxidant enzyme, kidney index and serum uric acid (UA) measurements were taken. The expression levels of the signalling pathway components were determined. KM effectively alleviated the symptoms of redness, swelling and pain; counteracted inflammatory cell infiltration; and increased antioxidant enzyme levels, reduced kidney index and serum UA levels through regulating UA excretion in MSU-induced mice. The expression of toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB)/nucleotide-binding oligomerization domain, leucine-rich repeat and pyrin domain-containing 3 (NLRP3) signalling pathway proteins and mRNA were reduced in the KM group. These results suggest that KM may be effective in alleviating GA through the TLR4/NF-κB/NLRP3 pathway.

Development of molecularly imprinted photonic crystal hydrogel based smart sensor for selective uric acid detection

Determination of uric acid (UA) concentration is important in clinical analysis, as its variation is an indication of several health-related conditions. Here, we discuss the development of a Molecularly imprinted photonic crystal hydrogel (MICPH)-based colourimetric sensor for the selective detection of UA. The developed MIPCH-UA sensor displays a bright structural colour, which varies as the sensor swells upon rebinding the UA molecules. The structural colour change is directly related to the concentration of the target molecule and can serve as an easy readout of the sensor response. This colour change can also be recorded spectrally, providing a quantitative measure of the sensor response. With a low limit of detection (LoD) of 1.01×10-9M, the sensor is capable of detecting low concentrations of UA. Moreover, the sensor endows the advantage of fast responsiveness and reusability when employed for UA assays. The sensor performance remains consistently reliable over an extended duration of up to one month, thereby ensuring cost-effectiveness in monitoring UA levels. The specific detection capability of the sensor allows the accurate and reliable measurement of UA in the presence of various interfering molecules and complex sample matrices. The structural colour change of the sensor was used to train a CNN-based deep learning algorithm to quantitatively predict the UA concentration. The integration of the machine learning algorithm with the developed sensor provides an accurate and efficient smart sensor platform well-suited for real-time sensing of uric acid.

Colorimetric and fluorometric determination of uric acid by a suspension-based assay using enzyme-immobilized micro-sized particles.

Daily monitoring of serum uric acid levels is very important to provide appropriate treatment according to the constitution and lifestyle of individual hyperuricemic patients. We have developed a suspension-based assay to measure uric acid by adding a sample solution to the suspension containing micro-sized particles immobilized on uricase and horseradish peroxidase (HRP). In the proposed method, the mediator reaction of uricase, HRP, and uric acid produces resorufin from Amplex red. This resorufin is adsorbed onto enzyme-immobilized micro-sized particles simultaneously with its production, resulting in the red color of the micro-sized particles. The concentration of resorufin on the small surface area of the microscopic particles achieves a colorimetric analysis of uric acid with superior visibility. In addition, ethanol-induced desorption of resorufin allowed quantitative measurement of uric acid using a 96-well fluorescent microplate reader. The limit of detection (3σ) and RSD (n = 3) were estimated to be 2.2 × 10-2μg/mL and ≤ 12.1%, respectively. This approach could also be applied to a portable fluorometer.

The oxalate-lowering effect of functional stirred yogurt in a rat model

Urolithiasis is a prevalent health issue that can potentially lead to kidney failure. Of the different kinds of kidney stones, the most common kind are calcium oxalate crystals. In this study, we investigated the impact of two probiotic lactobacilli preparations on urinary functions in rats that were fed a high-oxalate diet. Forty male Sprague-Dawley rats in all were split up into five groups, each with eight rats. Two groups were used: one as a positive control group that received a high-oxalate diet, and the other as a negative control group that received a regular, balanced diet. The remaining three groups were administered oral doses of the probiotic preparations in addition to being fed a high-oxalate diet. After 21 days, the rats were sacrificed, and biochemical analysis was conducted on their blood and urine samples, including measurements of creatinine, urea, uric acid, phosphorus, calcium, magnesium, aspartate transaminase (AST), acid and alkaline phosphatase, total proteins, and urine pH. The findings of the study confirmed that these probiotic preparations had a positive impact on kidney functions, potentially by enhancing oxalate metabolism in the intestines and/or reducing oxalate absorption from the gastrointestinal tract. Additionally, the counts of lactobacilli colonies in the fecal samples increased with both preparations, while the counts of coliforms decreased compared to the baseline. These results suggest that lactobacilli could be explored as a promising therapeutic approach in the prevention of urinary stones.

A Comprehensive Review on Serum Lactate Dehydrogenase (LDH) and Uric Acid in Preeclampsia: Implications for Maternal Health and Disease Severity.

Preeclampsia, a hypertensive disorder unique to pregnancy, remains a significant cause of maternal and fetal morbidity and mortality worldwide. Serum lactate dehydrogenase (LDH) and uric acid have garnered attention as potential biomarkers in understanding preeclampsia's pathophysiology and clinical management. Elevated LDH and uric acid levels have been associated with disease severity and adverse outcomes, highlighting their potential utility in risk stratification and guiding management strategies. This comprehensive review explores the roles of LDH and uric acid in preeclampsia, summarizing current evidence regarding their diagnostic, prognostic, and therapeutic implications. Future research directions are also discussed, including understanding and validation studies. Integrating LDH and uric acid measurements into routine clinical practice may facilitate early detection and intervention, ultimately improving outcomes for preeclamptic pregnancies. This review underscores the importance of serum biomarkers in enhancing our understanding and managing preeclampsia, aiming to optimize maternal and fetal health.

Distinct uric acid trajectories are associated with incident cardiac conduction block

BackgroundThe association of longitudinal uric acid (UA) changes with cardiac conduction block risk is unclear. We aimed to identify the trajectories of UA and explore its association with cardiac conduction block.MethodsA total of 67,095 participants with a mean age of 53.12 years were included from the Kailuan cohort in Tangshan, China, who were free of cardiac conduction block and with repeated measurements of UA from 2006 to 2012. UA trajectories during 2006 to 2012 were identified by group-based trajectory modeling. Cox proportional hazard regression models were used to assess the association of UA trajectories with cardiac conduction block.ResultsWe categorized three observed discrete trajectories of UA during 2006–2012 period: low-stable, moderate-stable, and high-stable. Over a median follow-up of 6.19 years, we identified 1405 (2.09%) incident cardiac conduction block. Compared to those in the low-stable trajectory, the adjusted hazard ratios (HRs) (95% confidence interval [CI]) of cardiac conduction block in the moderate-stable and high-stable trajectory were 1.30 (1.16–1.47) and 1.86 (1.56–2.22), and HRs of atrioventricular block were 1.39 (1.12–1.72) and 2.90 (2.19–3.83), and HRs of bundle branch blocks were 1.27 (1.10–1.47) and 1.43 (1.13–1.79). Notably, although the average UA level in the moderate-stable UA trajectory group is within the normal range, the risk of cardiac conduction block has increased.ConclusionsThe moderate-stable and high-stable trajectories are associated with increased risk for new-onset cardiac conduction block. Monitoring UA trajectories may assist in identifying subpopulations at higher risk for cardiac conduction block.

Associations between pesticide exposure with biomarkers of stroke risk factors in farmers.

The extensive use of pesticides may cause acute and chronic intoxication. Therefore, this study aimed to reveal the associations between pesticide exposure and serum markers for stroke risk factors in farmers. A cross-sectional study was conducted with farmers, who used chemical pesticides in Seloprojo Village, Ngablak District, Magelang Regency, Central Java Province, Indonesia. A questionnaire containing demographics, pesticide use, and aspects related to work was employed. Measurements of serum cholesterol, uric acid, glucose, cholinesterase, and fibrinogen levels were also conducted. Of the 106 subjects, 31 (29.2%) used organophosphates as chemical pesticides. There was a significant difference between organophosphate and nonorganophosphate groups in plasma fibrinogen levels. The organophosphate group had higher levels of fibrinogen (292.29 ± 67.56 mg/dL) than the non-organophosphate group (255.24 ± 38.90 mg/dL). Of the studied risk factors for stroke, there is a significant association between organophosphate exposure and increased plasma fibrinogen levels.

Electrochemical sensors based on the composite of reduced graphene oxide and a multiwalled carbon nanotube-modified glassy carbon electrode for simultaneous detection of hydroquinone, dopamine, and uric acid.

Using a simple drop-casting technique, we successfully fabricated a sensitive electrochemical sensor based on the composite of reduced graphene oxide (RGO) and multiwalled carbon nanotubes (MWCNT) deposited on the surface of a glassy carbon electrode (GCE) for individual and simultaneous measurements of hydroquinone (HQ), dopamine (DA), and uric acid (UA). The nanocomposite of RGO/MWCNT was further characterized in terms of its structural properties, surface morphology, and topography using Raman, FT-IR spectroscopy, SEM, HRTEM, and AFM. Then, the proposed sensor for simultaneous measurement of HQ, DA, and UA based on RGO/MWCNT-modified GCE was investigated for its electrochemical behavior and electroanalytical performances using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV). In addition, the composition ratio between RGO and MWCT was 1 : 1 showing the highest electrochemical response for simultaneous detection of HQ, DA, and UA. Owing to the synergistic effect between RGO and MWCNT leading to excellent conductivity properties, the proposed sensor exhibited improved electrochemical response at pH 7 toward the oxidation processes of HQ, DA, and UA on the surface of modified electrode. The proposed sensor demonstrated three well-defined anodic peaks of these analytes with their linear concentrations ranges of 3.0-150.0 μM for HQ, 4.0-100.0 μM for DA, and 2.0-70.0 μM for UA. The limit of detection values for the simultaneous detection of HQ, DA, and UA were found as follows 0.400 ± 0.014, 0.500 ± 0.006, and 0.300 ± 0.016 μM, respectively. The additional features of this proposed sensor are high reproducibility and stability for the simultaneous detection of HQ, DA, and UA with negligible interference effect from interferents such as Mg2+, K+, Cl-, ascorbic acid, and glucose. An acceptable percentage of recovery was also shown by this sensor for simultaneous measurements of HQ, DA, and UA using 6 samples of human urine. In summary, the RGO/MWCNT nanocomposite has been shown to be a promising platform for rapid, simple, and reliable determination of simultaneous measurements of HQ, DA, and UA in practical applications.

Serum Uric Acid as a Marker of Coronary Artery Disease in Type 2 Diabetes Mellitus Patients: An Observational Study

ABSTRACT Background: Cardiovascular disease is the most prevalent cause of morbidity and mortality in diabetic patients. Hypertension, obesity, and smoking are well-established risk factors for coronary artery disease (CAD) in diabetes. Hyperuricemia is an emerging risk factor for insulin resistance and cardiovascular disease. Our objective in the present study was to assess the association of serum uric acid with cardiovascular disease and its risk factors in type 2 diabetes mellitus. Methods: A cross-sectional study was carried out at a tertiary care hospital; a total of 100 patients who presented to the hospital with a diagnosis of type 2 diabetes mellitus were selected by simple random sampling technique and divided into two groups based on echocardiography and coronary angiography reports. Serum uric acid, glycosylated hemoglobin (HbA1c), lipid profile, and body mass index (BMI) measurements were performed. Data were analyzed into the SPSS version, and the Pearson coefficient was used to assess the association between uric acid and cardiovascular disease risk factors. P <0.05 was considered statistically significant. Results: The mean uric acid is higher (6.79 ± 1.42 mg/dL) in diabetic patients with CAD compared to diabetics without CAD (4.82 ± 1.66 mg/dL). A positive correlation was found between serum uric acid, BMI, and lipid profile. Conclusion: Serum uric acid was significantly associated with the presence of CAD and CAD risk factors and can be used as a predictive marker for cardiovascular outcomes in type 2 diabetes mellitus.

Associations of serum uric acid levels and anthropometric parameters with non-alcoholic fatty liver disease in healthy individuals: innovative insights from a cross-sectional study

Objective Non-alcoholic fatty liver disease (NAFLD is a spectrum of liver disease with a rising prevalence, ranging from simple steatosis to steatohepatitis and cirrhosis, where a significant minority face potential complications. Determining the predictive markers plays a crucial role. This study examined the relationship between serum uric acid (SUA) levels and NAFLD in healthy individuals and identified potential other predictors. Material and methods A cohort of 2162 healthy participants attending routine check-up visits between February 2021 and May 2023 were included. Participants underwent abdominal ultrasound, uric acid measurements, and anthropometric assessments by TANITA. NAFLD was graded using a "hepatic steatosis score." Statistical analysis included nonparametric tests, chi-squared tests, Fisher’s exact test, ROC curve analysis, and logistic regression. Results The median age was 45 years (range:18-65). 1017 were male, and 1145 were female. Among the participants, 53.9%, 26.3%, 17.9%, and 1.9% exhibited Grade 0, 1, 2, and 3 hepatic steatosis, respectively. ROC analysis showed 80.0% sensitivity and 78.8% specificity for detecting grade 2 or higher hepatic steatosis with a cutoff value of 5.21 mg/dl of SUA (AUC = 0.82, p < 0.001, 95%CI 0.79-0.84). There were significant associations between elevated uric acid levels and NAFLD. Participants with higher body fat percentages, BMI values, and waist-to-hip ratios also demonstrated an increased prevalence of steatosis. Gender significantly influenced liver steatosis, with males exhibiting higher grades compared to females. Logistic regression analysis highlighted positive associations between NAFLD and body fat percentage, waist-to-hip ratio, and uric acid levels. Each unit increase in uric acid levels corresponded to a 2.5-fold increase in the odds of NAFLD (p < 0.001, 95% CI = 2.20-2.84). Conclusion Our findings suggest a significant relationship between serum uric acid levels and NAFLD in healthy individuals. Elevated uric acid levels, in conjunction with other anthropometric parameters, may serve as potential predictive markers for NAFLD.

A Microfluidic Paper-based Analytical Device for Simultaneous Measurement of Albumin, Creatinine and Uric Acid in Urine based on Standard Addition Method

This work describes a simple method for the simultaneous measurement of urinary albumin, creatinine and uric acid using a standard addition approach on a microfluidic paper-based analytical device (µPAD). Hydrophobic barrier of the µPAD was created by stamping indelible ink onto a filter paper. The µPAD was designed with a flower-liked configuration. After aliquoting urine to a central sample zone, the sample flowed to ten surrounding channels, namely “the inner channels”, where the blank (water) or standard solutions had been added. The inner channels were connected to circular reagent zones where reagents had been immobilized. Tetrabromophenolphthalein ethyl ester, alkaline picrate, and a mixed solution of ferric chloride and ferric cyanide were used as the chromogenic reagents for the colorimetric detections of albumin, creatinine, and uric acid, respectively. Each reagent zone was linked with a circular detection zone through a second channel, namely “the outer channels”. The blue-, orange- and greenish-blue colored products were observed in the detection zones for the measurement of albumin, creatinine, and uric acid, correspondingly. A digital image of the µPAD was captured with a mobile phone. The color intensities were evaluated by ImageJTM and were employed for the quantitative analyses. The standard addition calibrations were found to be linear (r2 &gt; 0.99) for the spiked analyte concentrations up to 100 mg L-1 albumin, 1000 mg L-1 creatinine, and 50 mg dL-1 uric acid. The paper platform provided high precision (RSD &lt; 5 %) and good analytical recovery (91.8-109.7 %). Under paired t-test, the results obtained by the developed µPAD and the validating methods were not significantly different at 95 % confidence (albumin: tstat = -0.130, tcri = 3.182, creatinine: tstat = -0.133, tcri = 3.182, and uric acid: tstat = 1.119, tcri = 3.182).

A Comparative Study of Serum and Salivary Uric Acid Measurement in Pre-eclampsia and Normal Pregnancy in a Tertiary Care Hospital in Punjab: A Pilot Study

A Comparative Study of Serum and Salivary Uric Acid Measurement in Pre-eclampsia and Normal Pregnancy in a Tertiary Care Hospital in Punjab: A Pilot Study

Wearable Biosensor Utilizing Chitosan Biopolymer for Uric Acid Monitoring

A wearable biosensor was specifically engineered to measure uric acid, a biomarker present at wound sites. This biosensor, fabricated as a disposable and wearable device, was seamlessly integrated onto a polyethylene terephthalate (PET) substrate by utilizing carbon and silver conductive paste as the electrodes. The enzyme uricase was immobilized onto the working electrode by utilizing chitosan, a biocompatible material, to create this biosensor. Notably, the uric acid biosensor fabricated with chitosan showcased exceptional performance metrics, including remarkable output current values and impeccable stability. These findings suggest the prospective utilization of chitosan-based uric acid biosensors for the accurate measurement of uric acid on human skin in future applications.

Decorated graphene oxide with gold nanoparticles as a sensitive modified carbon paste electrode for simultaneous determination of tyrosine and uric acid

It is presented here as a simple, selective, rapid, low-cost, with a wide linear range method to simultaneously determine tyrosine and uric acid using a modified carbon paste electrode decorated with graphene oxide and gold nanoparticles (GO/AuNPs/MCPE). In order to characterize and evaluate the morphology and constituents of the nanostructures, X-ray diffraction spectroscopy, Transmission electron microscopes, Dynamic light scattering, Zeta potential, electrochemical impedance spectroscopy, and Voltammetry were employed. The current response on the surface of the modified electrode had a dynamic linear range relationship in the concentrations of 0.14–340.00 µmol L−1 and 0.06–141.00 µmol L−1 for tyrosine and uric acid, respectively, and the method detection limit (MDL) was 0.0060 µmol L−1 and 0.0037 µmol L−1, respectively. This modified electrode provided high stability, sensitivity, and acceptable reproducibility for voltammetric measurements of tyrosine and uric acid simultaneously in a biological matrix.