Detection Of Creatinine Research Articles

Self‐Calibrating Copper‐Based Metal Organic Frameworks for Ratiometric Electrochemical Sensing of Creatinine

AbstractNanostructures that can undergo redox reactions have significant potential for electrochemical analysis. They can act as signal amplifiers to determine concentrations of targets in biological samples. In this work, a rational combination of electroactive copper‐based metal‐organic frameworks (Cu‐MOFs) and ferrocene carboxylic acid (Fc) was designed for ratiometric electrochemical detection of creatinine. The synthesized Fc@Cu‐MOFs exhibited two redox signals from the Cu2+/Cu+ and Fe3+/Fe2+ systems in the skeleton of Cu‐MOFs and Fc, respectively. In the presence of chloride (Cl−), the oxidation current of Cu+ increased due to formation of solid‐state cuprous chloride (CuCl). Adding strong Cu+ chelators, e. g. creatinine, coordinated with Cu+ and caused the current output of solid‐state CuCl to decrease significantly. The anodic current of Fc did not appreciably change, serving as an internal reference signal. The ratiometric responses (ICu(I)/IFc) changed with increasing concentrations of creatinine from 0.017–130 μM with a detection limit (S/N=3) of 0.005 μM. The main advantages of Fc@Cu‐MOFs are the low LOD, high selectivity, and reliability, making it a suitable platform for determining creatinine in human serum and urine samples. The as‐fabricated sensor is a reliable approach for determining (bio) molecules that can form stable complexes with Cu+ ions.

Software Integrated Personalized Biosensing Device for Serum Creatinine Detection Based on Boron doped MXene Nanohybrid.

In recent years, an increase in the number of chronic kidney disease (CKD) cases has led to a global health burden majorly affecting underdeveloped and developing nations. A key biomarker for assessing the kidneys' normal functioning is creatinine, which is filtered out from the blood by the kidney. Thus, timely and specific detection of creatinine becomes necessary for diagnosis and subsequent treatment of CKD. Hence, in this study, we have tried to develop a field-deployable, software-integrated immunosensor for the detection of creatinine in a serum sample. The immunosensor was developed by incorporating gold nanoparticles, boron doped MXene, polyaniline, and anticreatinine antibody using an appropriate bioconjugation reaction. The developed sensor was able to detect creatinine in a linear dynamic range of 10 nM to 0.1 M with a limit of detection of 1.72 (±0.07) nM. The sensor was integrated with an indigenously developed software named "CretCheck" which simplifies the process of data analysis. The software integrated personalized biosensing device was used to find the creatinine concentrations directly from the obtained analytical signals. The developed immunosensor with the integrated software can also be implemented directly in primary health care facilities for creatinine detection in the future.

A NOVEL ELECTROCHEMICAL BIOSENSOR BASED ON CREATININE DEIMINASE FOR CREATININE ANALYSIS

This work presents the development of a new electrochemical biosensor based on creatinine deiminase for the determination of creatinine concentration in biological samples. The optimal method for immobilizing bioselective elements on the electrode surface was selected, specifically the covalent binding of creatinine deiminase in a BSA matrix using glutaraldehyde. The biosensors prepared in this way exhibited the highest sensitivity to creatinine and high reproducibility in the fabrication of biomembranes. The biosensor demonstrated a low limit of detection of creatinine, high signal stability (RSD = 3%), significant storage stability, and a wide linear range, enabling the detection of both normal and pathological creatinine concentrations in biological fluids. The study also investigated the influence of working solution parameters, such as ionic strength, buffer capacity, pH, and protein content, on the biosensor’s performance. The main analytical characteristics of the proposed electrochemical biosensor indicate its potential use for monitoring creatinine concentration in biological samples.

High-Performance Electrochemical Creatinine Sensors Based on β-Lead Dioxide/Single-Walled Carbon Nanotube Electrodes.

Creatinine is an important biomarker of kidney function and muscular metabolism. In this paper, we developed the β-lead dioxide/single-walled carbon nanotube (β-PbO2/CNT) and the β-PbO2/CNT ion-selective electrode (β-PbO2/CNT/ISE), which were used as highly sensitive potentiometric sensors for creatinine detection. The fabricated electrodes exhibited highly pH-sensitive characteristics due to the synergistic effect of the electrochemical properties of CNT and β-PbO2. Moreover, an ammonium-ion-selective membrane coating allowed the β-PbO2/CNT electrode to be NH4+-selective for direct detection of the ammonium ion. By exploiting the electrochemical characteristics of these electrodes, the creatinine assay was established through the one-step selective conversion of creatinine by creatinine deiminase, in which the OH- and NH4+ generated by the enzymatic reaction were detected using β-PbO2/CNT and β-PbO2/CNT/ISE electrodes as pH- and NH4+-responsive sensors, respectively. The total creatinine assay can be completed within ∼5 min. The assay results from β-PbO2/CNT and β-PbO2/CNT/ISE showed excellent sensitivity values of -75.56 and 64.62 mV in the detection range of 10-400 μM with a fast response (20 s), and the limits of detection were calculated to be 0.06 and 0.13 μM, respectively. Moreover, the developed creatinine sensor showed high selectivity against 11 interfering bio/chemical species with negligible interferences (selectivity coefficient <10-4) and excellent repeatability (>97% within 25 cycles) and long-term stability for 4 weeks of storage. In addition, the feasibility and practicality of the device were successfully demonstrated in human serum tests, with recoveries of 95-104% for PbO2/CNT and 92-110% for PbO2/CNT/ISE.

Electrochemical biosensors based on creatinine deiminase for creatinine detection

Electrochemical biosensors based on creatinine deiminase for creatinine detection

High aspect ratio copper nanowires modified screen-printed carbon electrode for interference-free non-enzymatic detection of serum creatinine in neutral medium

In this work, the affinity of copper to create a soluble coordination complex with creatinine was exploited for the electrochemical detection of creatinine levels in serum. High aspect ratio copper nanowires were synthesized by controlled hydrothermal method in the presence of dextrose and octadecyl amine. Disposable screen-printed electrode modified with copper nanowires demonstrated excellent sensing towards creatinine in 0.1 M phosphate buffer with a wide detection range of 50–500 µM. The developed sensor was found to be highly selective even in the presence of interfering molecules like glucose, ascorbic acid, urea, uric acid, and chloride. The proposed copper nanowire-based non-enzymatic creatinine sensor is highly promising for point-of-care testing applications.

A Simple and Efficient Colorimetric Detection of Creatinine Based on Citrate-Stabilized Gold Nanoparticles

A Simple and Efficient Colorimetric Detection of Creatinine Based on Citrate-Stabilized Gold Nanoparticles

Diaper-based wearable SERS sensing system with a silver nano dual-structure composite hydrogel for the detection of biomarkers and pH in urine

Wearable sensors are essential for continuous monitoring of an individual’s health status to enable personalized health management. Urine as a typical non-invasive biological fluid is rich in biological information. Although diaper-based biosensors have been developed, the development of wearable sensors for multiple biomarkers in urine remains a major challenge to be explored. In this paper, a hydrogel SERS sensor consisting of two metal nanostructures of silver nanowires (Ag NWs) and silver nanocubes (Ag NCs) was developed and adhered to nappies to form a wearable nappy-based SERS sensor for the rapid and sensitive detection of bio markers (creatinine, uric acid and bilirubin) and pH in urine. The hydrogel’s excellent adsorption and water-locking properties greatly simplify the collection of urine samples. At the same time, its encapsulation effect can effectively maintain the freshness of the urine sample and ensure the accuracy of the test. The introduction of silver nano dual-structure improves the antimicrobial properties of the hydrogel and reduces the risk of infection when the sensor comes into contact with the skin. Moreover, the silver nano dual-structure triggers abundant electromagnetic “hot spots” around intersecting nanojunctions and gaps, which greatly improves SERS sensitivity. For the detection of creatinine, uric acid and bilirubin, the LODs were as low as 0.59 μM, 69 nM, 89 nM. Finally, the urine pH was accurately detected using a functionalized Ag NWs-Ag NCs/CCNF/Gel/PVA hydrogel. This wearable diaper sensor is expected to be used for personal health condition monitoring and holds great promise for effective care of infants, the elderly, and those with limited mobility.

Red-emitting copper nanoclusters for ultrasensitive and selective detection of creatinine and its application in portable smartphone-based paper strips and polymer thin film

In this work, a quantitative paper-based sensor integrated with smartphone-application was developed using poly(sodium 4-styrenesulfonate) stabilized copper nanoclusters (PSS-CuNCs) as a fluorescence probe to detect creatinine (CRN). The surface morphology and optical properties of PSS-CuNCs were verified using UV–vis absorption, zeta-potential, photoluminescence, high resolution transmission electron microscopy (HR-TEM) and Fourier-transform infrared (FI-IR) and X-ray photoelectron (XPS) spectroscopy. PSS-CuNCs exhibited strong red fluorescence with the emission peak centered at 654 nm upon excitation at 390 nm. PSS-CuNCs was also used to determine CRN because of their excellent fluorescence properties. The fluorescence of PSS-CuNCs was quenched significantly by adding different concentrations of CRN, which mainly originated from the formation of ground state complexation. The PSS-CuNCs probe showed high sensitivity with a low limit of detection (LOD) of 2.48 nM and high selectivity even in the presence of other interfering analytes. This assay was also used to measure CRN in real samples. Additionally, test paper-based assay has been developed to detect CRN using smartphones. The developed assay provides a reliable, cost-effective, sensitive and portable on-site method to measure CRN levels by utilizing fluorescence color changes. Incorporation of PSS-CuNCs into poly(vinyl alcohol) resulted in the formation of fluorescent transparent polymer thin films with high photostability.

Simultaneous Detection of Biomarkers in Urine Using a Multicalibration Potentiometric Sensing Array Combined with a Portable Analyzer.

Domestic monitoring devices make real-time and long-term health monitoring possible, allowing people to track their health status regularly. Uric acid (UA), creatinine, and urea in urine are three important biomarkers for various diseases, especially kidney diseases. This work proposed a 10-channel potentiometric sensing array containing a UA electrode group, a creatinine electrode group, a urea electrode group, a pH electrode group, and one pair of reference channels, which could be connected with a portable potentiometric analyzer, realizing the simultaneous detection of UA, creatinine, urea, and pH in urine. The prepared Pt/carbon nanotubes (CNTs)-uricase, creatinine deiminase, Au@urease, and polyaniline were employed as the sensing materials, showing responses to four targets with high sensitivity and selectivity. To improve the accuracy of domestic monitoring, a calibration channel was integrated into each electrode group to calibrate the basic potential of the sensing channels, and the influences of pH and temperature on the responses were investigated through the pH electrode group and an external temperature probe to calibrate the slope and intercept. With the preset of the deduced calibration parameters and computational formula for the four targets in the analyzer in Lab Mode, the concentrations of UA, creatinine, and urea and the pH of the human urine samples were directly displayed on the screen of the analyzer in Practical Mode. The agreement of these results with those obtained from commercial kits and pH meters reveals the high potential of these methods for developing domestic devices to facilitate health monitoring.

Advancing paper microfluidics: A strategic approach for rapid fabrication of microfluidic paper-based analytical devices (µPADs) enabling in-vitro sensing of creatinine

Paper-based microfluidic sensors for point-of-care applications represent an exceptional strategy for facilitating rapid sensing within clinical settings. Despite their considerable promise, the ongoing research objective lies in efficiently printing hydrophobic microfluidic channels (µPADs) onto hydrophilic paper while minimizing expenditure. This research paper introduces an advanced, economic, and efficient method for the rapid fabrication of µPADs on paper substrates, enabling immediate colorimetric detection of creatinine in artificial urine using Jaffe’s reagent. The process involves a modified DIY RepRap 3D printer with an integrated technical drawing pen filled with the solution of Polydimethylsiloxane (PDMS) and hexane. This solution creates hydrophobic domain barriers on a flexible nylon-based paper substrate, effectively confining the aqueous medium within the microfluidic channels. We report visual detection of a broad spectrum of creatinine concentrations ranging from 5 mg/dL to 450 mg/dL through the vibrant Janovsky complex appearance on the microfluidic domains. The study identifies the limiting concentration on µPADs as 500 mg/dL. The innovative procedure demonstrates exceptional selectivity, exhibiting a maximum interference of only 0.97 % from potentially interfering substances. This rapid, naked-eye detection of creatinine on nylon 6,6 membranes offers a user-friendly and economical approach, enhancing the capabilities of colorimetric visualization in point-of-care applications.

Novel electrochemical sensing platform based on zinc metal organic frameworks/carbon nanofiber nanocomposite for detection of creatinine in human urine

A biomarker known as creatinine is a very important determinant of kidney failure. Creatinine concentrations in blood and urine can identify renal insufficiencies and muscle diseases. Monitoring the creatinine level and quick sensing requires a rapid, robust and simple method for determining the creatinine in human body. To overcome the universal challenge postured by this waste product of muscle, this study presents a novel strategy to fabricate an electrochemical sensor based on zinc MOFs, synthesized using terephthalic di- hydrazide (TPDD) as the organic ligand using a one-pot solvothermal method in the presence of carbon nanofiber matrix for enzyme less sensing the creatinine. The Zn-TPDD/CNF nanocomposite was well characterized by XRD, TGA, BET, XPS, FESEM, CV, DPV, and Raman spectroscopic techniques. Notably, this MOF anchored electrode owns important fundamental features such as large electro active exterior area, plentiful active sites, an immense operational linear range (5 to 250 μM), a nominal detection limit (10.04 nM), and an outstanding sensitivity towards creatinine. This Zn-TPDD/CNF/GCE electrode not only showcased more extraordinary electrochemical attributes, but its anti-interference stability, flexibility, reproducibility, storage stability, selectivity, and low detection threshold emphasize its ability for real-world applications with reasonable recoveries. Therefore, this modified electrode could be a potential tool for operative creatinine detection in urine.

A label-free sensing of creatinine using radio frequency-driven lab-on-chip (LoC) system

This paper presents a promising avenue of Radio Frequency (RF) biosensors for sensitive and real-time monitoring of creatinine detection. Knowing creatinine levels in the human body is related to its possible association with renal, muscular, and thyroid dysfunction. The detection was performed using an Inter-Digitated Capacitor (IDC) made of copper (Cu) metal over an FR4 substrate. To demonstrate our methodology, we have chosen Phosphate Buffer (PB) as our solvent for making the creatinine solutions of different concentrations. Moreover, Assayed Chemistry Control (ACC), a reference control consisting of human serum-based solutions has been mixed with the different concentrations of creatinine in a ratio of 1:9 to spike the creatinine value in the ACC solution. The sensor has been designed using a High-Frequency Structure Simulator (HFSS) tool with an operating frequency of 2.53 GHz. Then the design is fabricated over the FR4 printed circuit board (PCB) and tested using a Vector Network Analyzer (VNA). However, the sensitive area of the IDC is introduced to grade 4 Whatman filter paper for the Sample Under Test (SUT) handling unit. The main advantage of using Whatman filter paper is that the uniform spreading of liquid reduces experimental error, and less volume is required for testing the sample. The principal idea implemented in the biosensor design is to track the shift in the operating frequency in the presence of different concentrations of creatinine mix in ACC solution with Phosphate Buffer (PB) solution as a reference.

Nitrogen doped carbon dots and gold nanoparticles mediated FRET for the detection of creatinine in human urine samples

Serum creatinine (CR) is regarded as one of the most sought out prognostic biomarkers in medical evaluation of chronic kidney disease (CKD). In light of the diagnostic significance of CR, the utility of a fluorescence biosensor for its detection in human urine specimens has been explored based on Förster resonance energy transfer (FRET) across nitrogen-doped carbon dots (N-CDs) and gold nanoparticles (GNPs). A straightforward microwave-assisted synthesis procedure has been adopted to prepare N-CDs (λexcitation = 400 nm, λemission = 540 ± 5 nm) with bright green emissions. On addition of pre-synthesized GNPs, the radiative emanation of the N-CDs is completely suppressed on account of FRET across the N-CDs and the GNPs. About 77 % of their fluorescence intensity is recovered after adding CR to GNPs@N-CDs nanocomposite. The limit of detection for CR sensing is estimated as 0.02 µg•mL−1. This biosensor is selective enough to recognize CR in the existence of potential interfering substances (e.g., ascorbic acid, glucose, glutathione, urea, and electrolytes). Its practical utility for CR detection has been validated further on the basis of satisfactory correlation with the benchmark Jaffe method, as observed in artificial/human urine specimens. Consequently, this manuscript marks a pioneering report on employing CDs and GNPs-based FRET for identifying CR in urine specimens of CKD patients.

Non-Enzymatic Electrochemical Detection of Urine Creatinine Using Cobalt-Gold Bimetallic Nanoparticles

This work presents the development of a non-enzymatic electrochemical sensor for creatinine in a neutral medium using a cobalt-gold bimetallic nanoparticles modified platinum electrode. The voltammetric detection of creatinine in a neutral phosphate buffer was based on the formation of a soluble cobalt-creatinine complex. The sensor exhibited good selectivity and a detection limit (S/N = 3) of 2.25 mM with two linear ranges from 6.4 to 83.2 mM. The sensitivity of the sensor was 0.621 and 1.135 μA mM−1 cm−2 at lower (6.4–51.2 mM) and higher (51.2–83.2 mM) detection ranges, respectively. The sensor performance was validated using urine samples and creatinine spiked urine samples.

Improved solution-based SERS detection of creatinine by inducing hydrogen-bonding interaction for effective analyte capture

Recently, solution-based surface-enhanced Raman scattering (SERS) detection technique has been widely recognized due to its cost-effectiveness, simplicity, and ease of use. However, solution-based SERS is limited for practical applications mainly because of the weak adsorption affinity of the target biomolecules to the surface of plasmonic nanoparticles. Herein, we developed a highly sensitive solution-based SERS sensing platform based on mercaptopropionic acid (MPA)-capped silver-coated gold nanostars (SGNS@MPA), which allows efficient enrichment on the nanostars surface for improved detection of an analyte: creatinine, a potential biomarker of chronic kidney disease (CKD). The SGNS@MPA exhibited high enrichment ability towards creatinine molecules in alkaline medium (pH-9) through multiple hydrogen bonding interaction, which causes aggregation of the nanoparticles and enhances the SERS signal of creatinine. The detection limit for creatinine was achieved at 0.1 nM, with a limit of detection (LOD) value of 14.6 pM. As a proof-of-concept demonstration, we conducted the first quantitative detection of creatinine in noninvasive human fluids, such as saliva and sweat, under separation-free conditions. We achieved a detection limit of up to 1 nM for both saliva and sweat, with LOD values as low as 0.136 nM for saliva and 0.266 nM for sweat. Overall, our molecular enrichment strategy offers a new way to improve the solution-based SERS detection technique for real-world practical applications in point-of-care settings and low-resource settings.

Rapid Conductometric Sensing of Chronic Kidney Disease Biomarkers: Specific and Precise Detection of Creatinine and Cystatin C in Artificial Saliva

AbstractChronic kidney disease (CKD) has asymptomatic early stages, whereby early detection is crucial to prevent its complications and progression. Creatinine and cystatin C (cysC) assays are known for assessing kidney function but there are limited point‐of‐care diagnostics which are rapid, precise, and easy to use. Here, high resistivity silicon conductometric sensors for detection of creatinine and cysC with a 10 min sample incubation is introduced. The sensors provide resistance‐based signals that can be quantified and measured wirelessly. The sensors successfully detect creatinine and cysC in both phosphate buffer saline (PBS) and artificial saliva in the nanomolar range, being able to distinguish their critical concentrations at 8.8 and 20 nm, respectively, for diagnosis of early stage of CKD. The detection limit for both creatinine and cysC is determined as 0.01 nm which is more than 500× and 1000× times lower than critical concentrations for the two biomarkers, respectively. Finally, these sensors are incorporated into a battery‐free, miniaturized electronic device for wireless biomarker detection as a proof‐of‐concept demonstration of a point‐of‐care tool for assessing kidney functionality.

#1524 SKLB023 alleviates kidney inflammation and apoptosis via inhibiting TLR4-mediated NF-κB p65 and MAPK signaling pathways in septic AKI mice

Abstract Background and Aims Sepsis is a severe and complex clinical syndrome resulting from the host's inflammatory response to infection. Acute kidney injury (AKI) is one of the major complications of sepsis with high morbidity and mortality, namely sepsis-associated acute kidney injury (S-AKI). Despite current advances, effective drugs for treatment of S-AKI are scarce. SKLB023 is a small molecule compound designed based on 5-benzylidene-thiazolidine-2,4-dione, which has a potent anti-inflammatory effect with favorable efficacy in rheumatoid arthritis. This study aims to evaluate the efficacy of SKLB023 in treating S-AKI and to explore the underlying mechanisms. Method S-AKI was induced by cecal ligation puncture (CLP) and intraperitoneal injection of LPS (10 mg/kg) in male C57BL/6 mice. SKLB023 (25 mg/kg, 50 mg/kg) was administrated by gavage three days in advance and 30 minutes earlier on the day of modeling. Mice death per group was recorded for 100 hours after CLP to evaluate the effect of SKLB023 on the survival rate of S-AKI mice. Other mice were sacrificed 16 hours after model establishment, blood and kidney specimens were collected. Renal function was measured by the detection of serum creatinine (SCr) and blood urea nitrogen (BUN). Kidney pathological injury was evaluated by the expression of kidney injury markers and the assessment of PAS/HE stainings. In vitro experiments were performed with LPS stimulation of TCMK-1 cells and SKLB023 intervention, and the doses were determined by CCK-8 assay. Possible molecular mechanisms involved in SKLB023 against S-AKI were screened by bioinformatics analysis and further validated in vivo and vitro. RT-PCR, western blot, immunofluorescence, and immunohistochemistry were applied to detect renal inflammation and apoptosis. To determine the role of TLR4, TLR4 siRNA and TLR4-KO mice were applied in S-AKI model, and TLR4 expression and the activities of NF-κB p65 and MAPK signaling pathway were assessed. One-way ANOVA was performed for comparison between groups, and logrank analysis was used for comparison of survival curve. P &amp;lt; 0.05 was considered as statistically significant. Results The S-AKI model was successfully established by CLP and LPS injection with obvious renal dysfunction and kidney pathological damage. The mice administrated with SKLB023 had a higher survival rate, lower levels of Scr and BUN, and improved kidney pathological injury than the mice in the CLP group. Transcriptomic analysis identified TLR4-mediated downstream signaling pathways as the potential mechanism of SKLB023 and further experiments in vivo and in vitro proved that SKLB023 regulated the expression of TLR4 and the activities of NF-κB p65 and MAPK signaling pathway in S-AKI mice and LPS-stimulated TCMK-1 cells. Moreover, TLR4 inhibited the expression of inflammatory cytokines including TNF-α, IL-1β, IL-6, iNOS, COX-2, HMGB-1 and alleviated kidney apoptosis in S-AKI mice and LPS-treated TCMK-1 cells. Additionally, knockout of TLR4 remarkably improved inflammation, apotosis, and kidney injury in LPS-treated mice and TCMK-1 cells. Conclusion SKLB023 confers renoprotective effects in S-AKI by modulating inflammation and apoptosis. TLR4 is a key target in S-AKI, and SKLB023 inhibits inflammation and apoptosis by inhibiting the activities of TLR4 mediated NF-κB p65 and MAPK pathways. SKLB023 may be proposed as one of the potential preventive and therapeutic agents for S-AKI.

DNA Framework-Programmed Nanoscale Enzyme Assemblies.

Multienzyme assemblies mediated by multivalent interaction play a crucial role in cellular processes. However, the three-dimensional (3D) programming of an enzyme complex with defined enzyme activity in vitro remains unexplored, primarily owing to limitations in precisely controlling the spatial topological configuration. Herein, we introduce a nanoscale 3D enzyme assembly using a tetrahedral DNA framework (TDF), enabling the replication of spatial topological configuration and maintenance of an identical edge-to-edge distance akin to natural enzymes. Our results demonstrate that 3D nanoscale enzyme assemblies in both two-enzyme systems (glucose oxidase (GOx)/horseradish peroxidase (HRP)) and three-enzyme systems (amylglucosidase (AGO)/GOx/HRP) lead to enhanced cascade catalytic activity compared to the low-dimensional structure, resulting in ∼5.9- and ∼7.7-fold enhancements over homogeneous diffusional mixtures of free enzymes, respectively. Furthermore, we demonstrate the enzyme assemblies for the detection of the metabolism biomarkers creatinine and creatine, achieving a low limit of detection, high sensitivity, and broad detection range.

Boron nitride nanotube-based creatinine biosensors for athlete physical condition monitoring

Monitoring creatinine levels is critical for evaluating renal function and muscular health in athletes. Creatinine is a waste product of creatine metabolism in skeletal muscle, and is filtered by the kidneys at a relatively constant rate. Elevated serum creatinine can indicate impaired kidney function, rhabdomyolysis, or skeletal muscle trauma. In athletes, creatinine levels increase after intense exertion due to muscle breakdown and myoglobin release. Abnormal creatinine signifies poor training adaptation, overtraining, or trauma. Therefore, close monitoring of creatinine in athletes provides insight into their physical condition. Current laboratory methods for measuring creatinine like Jaffe reaction and high-performance liquid chromatography are accurate but time-consuming, requiring blood sampling. Biosensors offer rapid, painless creatinine detection from small volumes, but current versions suffer from instability, use of mediators, and lack portability. Boron nitride nanotubes (BNNTs) are promising materials for electrochemical biosensing due to their structure, surface chemistry, and biocompatibility. Here, we report BNNT-based electrochemical biosensors for detecting creatinine in blood samples from athletes. BNNTs synthesized by induction thermal plasma technique were used to immobilize creatinine metabolizing enzymes. Creatinine levels were measured by chronoamperometry and compared to isotope dilution mass spectrometry. We demonstrate high sensitivity and selectivity of the BNNT biosensor with facile fabrication method and portable platform, promising for rapid creatinine monitoring in athletes. This can provide insight into muscular damage and renal function during training and competition.