Portable Glucose Research Articles

Construction of Pt/Ni/NiFe2O4/C nanocomposite with one dimensional hollow structure for portable glucose sensing application.

Designing portable electrochemical sensors combined with highly efficient glucose oxidation electrodes offers a significant opportunity for convenient glucose detection. In this report, we present the design and preparation of platinum deposited Ni/NiFe2O4/Carbon composite (Pt/Ni/NiFe2O4/C) derived from Ni/Fe metal-organic frameworks (MOFs) followed by Pt deposition. Energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and electron microscopy (EM) were utilized to analyze the crystal structure, morphology, and chemical composition of the resulting materials. The glucose sensing capabilities of the optimal Pt/Ni/NiFe2O4/C-3 were assessed using amperometry methods on a smartphone-based portable device. Acting as a nonenzymatic glucose sensor, the Pt/Ni/NiFe2O4/C-3 electrode demonstrated notable sensitivity and a low limit of detection for glucose. The portable sensor exhibits high sensitivities of 131.88μM mM cm-2 at low glucose concentration (3-500μM) and 29.52 μA mM cm-2 at high glucose concentration (700-4000μM), achieving a low detection limit of 1.1μM (S/N = 3). The sensor also demonstrates enhanced selectivity and stability for detecting glucose. Furthermore, the portable sensor exhibits a clear step-ampere response in the detection of serum samples with satisfactory recovery ranging from 99.30 to 101.32%. This suggests the significant potential of portable glucose sensing applications.

High-Performance and novel photoactive Hetrostructured Field effect transistor for non-enzymatic glucose sensing

Field Effect Transistor (FET) is emerging as a next generation biosensor possessing the potential to adapt to diverse nanostructures while providing a stable and economically practical platform for achieving high sensitivity and selectivity for the analyte detection. Herein, the study demonstrates the application of an effective g-C3N4 and BiVO4 based photoactive hetrostructures to develop a high performance, non-enzymatic glucose sensing field effect transistor. g-C3N4 nanosheets were synthesized by thermal oxidation of thiourea which were sequentially used for carbon doping to fabricate heterostructures with BiVO4 using Carbon nanotubes (CNT) and gold (Au) nanoparticles as mediators for electrons. Four different hetrostructures BiVO4/g-C3N4, g-C3N4/CNT/BiVO4 g-C3N4/CNT/Au/BiVO4 and C-doped g-C3N4/CNT/Au/BiVO4 were fabricated for channel region to be utilized in FET. The fabricated channels were assessed for improvement g-C3N4/BiVO4 in absorbance, reduction in recombination losses by decreased energy band gap and current–voltage variation. The morphological and structural analysis was confirmed by X-ray diffraction (XRD) and Transmission electron Microscopy (TEM). Current- Voltage (IV) analysis of the fabricated channels was compared for the same amount of glucose concentration. The fabricated C-doped g-C3N4/CNT/Au/BiVO4 channel region based FET demonstrated long term stability after multiple uses, excellent sensitivity and enhanced photocatalytic performance. It also proved to be greatly beneficial in terms of ease of production, simplicity of usage and small size. It has the potential to recreate portable glucose biosensors for real time sensing while also providing additional benefit of other sensing biomolecules.

Technological Advances of Wearable Device for Continuous Monitoring of In Vivo Glucose.

Managing diabetes is a chronic challenge today, requiring monitoring and timely insulin injections to maintain stable blood glucose levels. Traditional clinical testing relies on fingertip or venous blood collection, which has facilitated the emergence of continuous glucose monitoring (CGM) technology to address data limitations. Continuous glucose monitoring technology is recognized for tracking long-term blood glucose fluctuations, and its development, particularly in wearable devices, has given rise to compact and portable continuous glucose monitoring devices, which facilitates the measurement of blood glucose and adjustment of medication. This review introduces the development of wearable CGM-based technologies, including noninvasive methods using body fluids and invasive methods using implantable electrodes. The advantages and disadvantages of these approaches are discussed as well as the use of microneedle arrays in minimally invasive CGM. Microneedle arrays allow for painless transdermal puncture and are expected to facilitate the development of wearable CGM devices. Finally, we discuss the challenges and opportunities and look forward to the biomedical applications and future directions of wearable CGM-based technologies in biological research.

Tyramine-Invertase Bioconjugate-Amplified Personal Glucose Meter Signaling for Ultrasensitive Immunoassay.

Highly sensitive and facile detection of low levels of protein markers is of great significance for the early diagnosis and efficacy monitoring of diseases. Herein, aided by an efficient tyramine-signal amplification (TSA) mechanism, we wish to report a simple but ultrasensitive immunoassay with signal readout on a portable personal glucose meter (PGM). In this study, the bioconjugates of tyramine and invertase (Tyr-inv), which act as the critical bridge to convert and amplify the protein concentration information into glucose, are prepared following a click chemistry reaction. Then, in the presence of a target protein, the sandwich immunoreaction between the immobilized capture antibody, the target protein, and the horseradish peroxidase (HRP)-conjugated detection antibody is specifically performed in a 96-well microplate. Subsequently, the specifically loaded HRP-conjugated detection antibodies will catalyze the amplified deposition of a large number of Tyr-inv molecules onto adjacent proteins through highly efficient TSA. Then, the deposited invertase, whose dosage can faithfully reflect the original concentration of the target protein, can efficiently convert sucrose to glucose. The amount of finally produced glucose is simply quantified by the PGM, realizing the highly sensitive detection of trace protein markers such as the carcinoembryonic antigen and alpha fetoprotein antigen at the fg/mL level. This method is simple, cost-effective, and ultrasensitive without the requirement of sophisticated instruments or specialized laboratory equipment, which may provide a universal and promising technology for highly sensitive immunoassay for in vitro diagnosis of diseases.

Fabrication of flexible glucose sensor based on heterostructure ZnO nanosheets decorated PU/Chitosan-PANI hybrid nanofiber

Designing and fabrication of immensely accurate, affordable, sensitive, and portable glucose sensors is rapidly increasing in clinical applications. However, commercialization of wearable sensors has been impeded by inadequate conductivity, insufficient durability, poor flexibility, and enzyme immobilization. Herein, a scalable approach for fabricating a nanofiber-based highly electroactive, flexible, and disposable (PUC-PANI-ZnO@GOx) sensor that can assess glucose stimuli with sufficient liquid permeability by anchoring ZnO nanosheets over polyaniline (PANI) coated polyurethane-chitosan (PU-Chitosan; PUC) fibrous mat followed by glucose oxidase (GOx) immobilization is described. Regarding the electrocatalytic performance, PUC-PANI-ZnO@GOx sensor showed a high sensitivity (∼998.72 µA mM−1 cm−2) and a low detection limit (∼7.31 µM) for a broad linear range of 0.01 – 9.48 mM with acceptable stability and reproducibility. The fabricated sensor was highly selective towards glucose in the presence of exogenous and endogenous interfering species. To the best of our knowledge, this novel polymer-based nanocomposite adorned on nanofiber substrate was utilized for the first time for the fabrication of a flexible glucose sensor. It can be used for producing a large-scale, cost-effective, and high-performing sensor. Hence, this sustainable and eco-friendly approach can lead to new techniques for designing next-generation wearable and implantable glucose sensors.

Portable glucose sensing analysis based on laser-induced graphene composite electrode.

In this work, a portable electrochemical glucose sensor was studied based on a laser-induced graphene (LIG) composite electrode. A flexible graphene electrode was prepared using LIG technology. Poly(3,4-ethylene dioxythiophene) (PEDOT) and gold nanoparticles (Au NPs) were deposited on the electrode surface by potentiostatic deposition to obtain a composite electrode with good conductivity and stability. Glucose oxidase (GOx) was then immobilized using glutaraldehyde (GA) to create an LIG/PEDOT/Au/GOx micro-sensing interface. The concentration of glucose solution is directly related to the current value by chronoamperometry. Results show that the sensor based on the LIG/PEDOT/Au/GOx flexible electrode can detect glucose solutions within a concentration range of 0.5 × 10-5 to 2.5 × 10-3 mol L-1. The modified LIG electrode provides the resulting glucose sensor with an excellent sensitivity of 341.67 μA mM-1 cm-2 and an ultra-low limit of detection (S/N = 3) of 0.2 × 10-5 mol L-1. The prepared sensor exhibits high sensitivity, stability, and selectivity, making it suitable for analyzing biological fluid samples. The composite electrode is user-friendly, and can be built into a portable biosensor device through smartphone detection. Thus, the developed sensor has the potential to be applied in point-of-care platforms such as environmental monitoring, public health, and food safety.

A computer vision enhanced smart phone platform for microfluidic urine glucometry.

Glucose is an important biomarker for diagnosing and prognosing various diseases, including diabetes and hypoglycemia, which can have severe side effects, symptoms, and even lead to death in patients. As a result, there is a need for quick and economical glucose level measurements to help identify those at potential risk. With the increase in smartphone users, portable smartphone glucose sensors are becoming popular. In this paper, we present a disposable microfluidic glucose sensor that accurately and rapidly quantifies glucose levels in human urine using a combination of colorimetric analysis and computer vision. This glucose sensor implements a disposable microfluidic device based on medical-grade tapes and glucose analysis strips on a glass slide integrated with a custom-made polydimethylsiloxane (PDMS) micropump that accelerates capillary flow, making it economical, convenient, rapid, and equipment-free. After absorbing the target solution, the disposable device is slid into the 3D-printed main chassis and illuminated exclusively with Light Emitting Diode (LED) illumination, which is pivotal to color-sensitive experiments. After collecting images, the images are imported into the algorithm to measure the glucose levels using computer vision and average RGB values measurements. This article illustrates the impressive accuracy and consistency of the glucose sensor in quantifying glucose in sucrose water. This is evidenced by the close agreement between the computer vision method used by the sensor and the traditional method of measuring in the biology field, as well as the small variation observed between different sensor performances. The exponential regression curve used in the study further confirms the strong relationship between glucose concentrations and average RGB values, with an R-square value of 0.997 indicating a high degree of correlation between these variables. The article also emphasizes the potential transferability of the solution described to other types of assays and smartphone-based sensors.

Portable glucose detector based on nickel oxide modified Screen Printed Carbon Electrode (SPCE)

A portable and low-cost system prototype for glucose detector based on LMP91000EV M potentiostat has been created. Characterization of Screen-Printed Carbon Electrodes (SPCE) without modification (bare SPCE) and modified nickel oxide (NiO/SPCE) was carried out with a commercial potentiostat to see the effect of nickel oxide in detecting glucose. Through the electrochemical impedance spectroscopy method, the Rct value of 1,276.79 Ω is obtained for NiO/SPCE and 429.06 Ω for bare SPCE, so that NiO/SPCE has a slower electron transfer rate. Meanwhile, through the cyclic voltammetry method, the surface-active electrode area is 7.1×10-2cm2 for NiO/SPCE and 6.9×10-2 cm2 for bare SPCE, so that NiO/SPCE is more sensitive in detecting glucose. When the glucose concentration is varied, the Limit of Detection (LOD) and Limit of Quantitation (LOQ) values of NiO/SPCE are smaller, specifically 1.807 mM and 6.024 mM than bare SPCE, specifically 2.629 mM and 8.762 mM, so NiO/SPCE is more sensitive. When the scan rate is varied, the gradient value of NiO/SPCE is smaller, specifically -8.14×10-4 mA s/mV than bare SPCE, specifically -9.62×10-4 mA s/mV, so NiO/SPCE is not more sensitive. Next, comparing a prototype system that Trans Impedance Amplifier (TIA) gain is varied and a commercial potentiostat. As a result, the cyclic voltammogram per cycle on commercial potentiostat is more stable. The smaller the TIA gain on the system prototype, the more stable it is, this is because the noise that is amplified is getting smaller.

Construction of a portable enzyme-free electrochemical glucose detection system based on the synergistic interaction of Cu-MOF and PtNPs

Three enzyme-free electrochemical glucose (GLU) sensors with bimetallic structures were constructed by electrodeposition of gold and copper nanoparticles (AuNPs/CuNPs), nickel and copper nanoparticles (NiNPs/CuNPs), and a copper-based metal-organic framework (Cu-MOF) combined with PtNPs, respectively. Amongst, the Cu-MOF/PtNPs on a gold electrode (GE) exhibited the best catalytic performance for GLU oxidation due to the synergistic amplification. The relevant electrochemical behaviour of GLU showed that two OH- and two electrons were involved in the process. The differential pulse voltammetry (DPV) enables the establishment of linearity in the concentration of 0.40–25.00 mM, with a detection limit (LOD) of 0.06 mM and a sensitivity of 158.41 µA·mM−1cm−2. In addition, the Cu-MOF/PtNPs/GE sensor was used to detect GLU in oral liquid as well as human serum samples with a recovery rate of 97.00–103.98% and RSD less than 3.59%. Finally, a portable electrochemical detection system based on the STM32F103C8T6 microcontroller, obtained a GLU concentration 5.24 mM while detecting in a diluted injection where the value 5.40 mM was recorded by a commercial meter to show the system has very broad application prospects in the point-of-care setting.

Design of a portable sweat glucose testing system

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A hand-held electrochemiluminescence biosensor for detection of carcinoembryonic antigen

After the development of portable glucose biosensor, challenges have remained to fabricate more portable devices for sensitive and reproducible detection of other biomarkers. Here, we fabricated a hand-held device for the quantification of carcinoembryonic antigen (CEA) or any other biomarkers based on electrochemiluminescence (ECL) using a bipolar electrode (BPE). The detection mechanism was based on a sandwich assay composed of a capture antibody and a secondary antibody conjugated with a robust ECL reporter. The ECL reporter was fabricated by conjugation of luminol on streptavidin-coated gold nanoparticle (Lum@SA-AuNP), leaving the biotin binding sites of the streptavidin intact for further conjugation with secondary antibody. This novel controlled functionalization strategy significantly enhanced the reproducibility and robustness of the biosensor. Moreover, an inventive parabolic reflector was implemented in the design, in order to maximize the lights to be captured by the photodiode (detector) and measured by a simple multimeter. Due to the synergetic signal amplification, the developed biosensor demonstrated a low sensitivity of 2.51 ng/ml with a linear detection range from 5 to 300 ng/ml with the ability to perform well in spiked-in samples. The designed sensing mechanism can definitely pave the way for further development of miniaturized devices in multiple formats.

Towards self-driven and enzyme-free sweat glucose photoelectrochemical sensing via decorating CuO nanoparticles on TiO2 hierarchical nanotubes

It is of great importance to develop a non-invasive and portable glucose sensor to address challenges and obstacles brought by invasive glucose sensors, such as negative physical and psychological impacts to patients during the fingertip blood collection, limited environment of use for enzyme-based electrodes, and cumbersome active-driven integrated devices. Photoelectrochemical (PEC) sensors have great potential in this regard. In this work, self-driven and enzyme-free sweat glucose PEC sensing is realized by constructing TiO2 hierarchical nanotubes modified by CuO nanoparticles (CuO@TiO2 HNT). A sensitivity of 138.9 μA mM−1 cm−2 in the low concentration range (< 200 μM) and a detection limit of 0.7 μM (Signal/Noise=3) are achieved by the as-prepared CuO@TiO2 HNT photoelectrode at relatively zero bias. The testing results for sweat glucose detection before and after meal consumption are consistent with those from commercial glucometers. The CuO@TiO2 HNT photoelectrode works well at absolutely zero bias and in a wide temperature range (e.g., 0–60 °C). The extraordinary sensing performance can be mainly attributed to the following two factors: (1) the TiO2 hierarchical nanotubes have an excellent light-capturing property and large specific surface area, and (2) the CuO nanoparticles substantially facilitate surface-carrier transfer for the glucose oxidation reaction. This work provides an enzyme-free sensing photoelectrode for self-driven sweat glucose detection and an alternative route to portable and noninvasive sensing of glucose.

Portable Amperometric Glucose Detection based on NiS/CuS Nanorods Integrated with a Smartphone Device

Glucose detection is particularly important for clinical diagnosis and personal prevention and control. Herein, the smartphone-based amperometric glucose sensors were constructed using the NiS/CuS nanorods (NRs) as sensing electrodes. The NiS/CuS NRs were prepared through a facile hydrothermal process accompanied by the subsequent vulcanization treatment. The morphological and structural properties of NiS/CuS NRs were characterized with SEM, EDS, XRD, and XPS. Electrochemical measurements including cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy display that NiS/CuS NRs can act as highly efficient electrocatalyst for glucose detection. The NiS/CuS NRs electrodes present a wide detection range of 1–8000 μM for glucose sensing with the sensitivity of 956.38 μA·mM&lt;sup&gt;−1&lt;/sup&gt;·cm&lt;sup&gt;−2&lt;/sup&gt;. The detection limit was 0.35 μM (S/N=3). When employed in smartphone-based glucose sensing device, they also display a high sensitivity of 738.09 μA·mM&lt;sup&gt;−1&lt;/sup&gt;·cm&lt;sup&gt;−2&lt;/sup&gt; and low detection limit of 1.67 μM. Moreover, the smartphone-based glucose sensing device also presents favorable feasibility in determination of glucose in serum samples with the recoveries ranging between 99.5 and 105.8%. The results may provide a promising viewpoint to design other new portable glucose sensors.

CRISPR-powered biosensing platform for quantitative detection of alpha-fetoprotein by a personal glucose meter

Alpha-fetoprotein (AFP) is an important protein biomarker of liver cancer, as its serum levels are highly correlated with the progression of disease. Conventional immunoassays for AFP detection rely on enzyme-linked immunosorbent assay analyses with expensive and bulky equipment. Here, we developed a simple, affordable, and portable CRISPR-powered personal glucose meter biosensing platform for quantitative detection of the AFP biomarker in serum samples. The biosensor takes advantage of the excellent affinity of aptamer to AFP and the collateral cleavage activity of CRISPR-Cas12a, enabling sensitive and specific CRISPR-powered protein biomarker detection. To enable point-of-care testing, we coupled invertase-catalyzed glucose production with the glucose biosensing technology to quantify AFP. Using the developed biosensing platform, we quantitatively detected AFP biomarker in spiked human serum samples with a detection sensitivity of down to 10 ng/mL. Further, we successfully applied the biosensor to detect AFP in clinical serum samples from patients with liver cancer, achieving comparable performance to the conventional assay. Therefore, this novel CRISPR-powered personal glucose meter biosensor provides a simple yet powerful alternative for detecting AFP and potentially other tumor biomarkers at the point of care.

Панкреатогенный сахарный диабет: особенности развития, клинического течения, диагностики и лечения

The features of development, characteristic clinical symptoms, laboratory, instrumental methods of examination and the basic principles of therapy of pancreatogenic diabetes mellitus (DM) are determined. Correlations in the development and course of the disease were revealed. It has been proven that pancreatogenic diabetes occurs significantly more often in men, more than half of whom abuse alcohol and smoke, while after surgery for pancreatic necrosis, patients with pancreatogenic diabetes statistically significantly begin to drink less alcohol. According to a scientific study, the duration of pancreatogenic DM is closely interrelated with the duration of chronic pancreatitis. The low level of C-peptide confirms an early decrease in insulin secretion and, accordingly, the need for insulin therapy. Irregular intake of enzymes significantly contributes to exacerbations of chronic pancreatitis, worsens the course of diabetes and leads to the development of diabetic complications. It was noted that with the duration of pancreatogenic diabetes, the risk of hypoglycemia increases statistically significantly, which certainly requires regular blood glucose testing. Self-monitoring of blood glucose in patients with DM should be carried out with the help of modern, accurate and easy-to-use portable glucose meters, one of which is the Contour Plus Uan.

Accurate Post-Calibration Predictions for Noninvasive Glucose Measurements in People Using Confocal Raman Spectroscopy.

In diabetes prevention and care, invasiveness of glucose measurement impedes efficient therapy and hampers the identification of people at risk. Lack of calibration stability in non-invasive technology has confined the field to short-term proof of principle. Addressing this challenge, we demonstrate the first practical use of a Raman-based and portable non-invasive glucose monitoring device used for at least 15 days following calibration. In a home-based clinical study involving 160 subjects with diabetes, the largest of its kind to our knowledge, we find that the measurement accuracy is insensitive to age, sex, and skin color. A subset of subjects with type 2 diabetes highlights promising real-life results with 99.8% of measurements within A + B zones in the consensus error grid and a mean absolute relative difference of 14.3%. By overcoming the problem of calibration stability, we remove the lingering uncertainty about the practical use of non-invasive glucose monitoring, boding a new, non-invasive era in diabetes monitoring.

NSRR Microwave Sensor Based on PLL Technology for Glucose Detection

Microwave biosensor shows great potential in mediator-free glucose detection. However, most microwave biosensors are passive devices; therefore, the high-stability and SNR frequency spectrum are necessary for ensuring the detection precision. In this article, a nested split-ring resonator (NSRR) microwave sensor integrated with phase-locked loop (PLL) technology is proposed for building a portable glucose detection system. PLL drives the NSRR operating at the specific frequency, in which the insertion loss is utilized to characterize the glucose level. By establishing the noise contribution model of PLL to NSRR, the loop parameters of PLL are optimized for higher linearity and sensitivity. The results show that when the loop bandwidth <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$K$ </tex-math></inline-formula> is set to 20 kHz for a Type-II fourth-order PLL, −76.3 dBc of spur suppression is achieved in the noise-sensitive area (660–760 MHz). In this case, the operation frequency is set at 743 MHz to realize a sensitivity of 17.2 dB/mg mL−1 and linearity of 0.97 for glucose detection.

Novel biosensor platform for glucose monitoring via smartphone based on battery-less NFC potentiostat

Near-field communication (NFC) was used to control a portable glucose biosensor for diabetes diagnosis. The system comprised a smartphone and an NFC potentiostat connected to a screen-printed carbon electrode (SPCE) modified with Prussian blue-graphene ink and functionalized with gold nanoparticles-embedded poly (3,4ethylene dioxythiophene):polysulfonic acid coated with glucose oxidase (GOx-AuNPs-PEDOT:PSS/PB-G). GOx catalyzed the glucose redox reaction while the conductivity and sensitivity of the AuNPs-PEDOT:PSS composite enhanced electron transfer to the PB‐G, which was used as a mediator. The fabrication process was characterized by scanning electron microscopy (SEM) with energy dispersibe x-ray analysis (EDX). The platform was electrochemically characterized by electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The NFC biosensing device was then applied to quantify glucose in human blood serum by amperometry. The linear concentration range and detection limit for glucose were 0.5–500 μM and 0.15 μM, respectively. The accuracy of the device was good and results were in agreement with the results obtained from the standard hospital method. This NFC glucose sensing device can be a simple, sensitive, selective and portable platform for medical diagnosis.

Recent advances in the detection of contaminants by portable glucose meter in food samples

Portable glucose meter (PGM) has played vital roles in the field of medicine, with advantages of accurate and quantitative results, portability, easy operation, and low cost. Recently, more and more researchers have extended the application of PGM in detecting foods contaminations. In this paper, a review of the application of PGM based on target recognition elements, such as antibody–antigen reaction, molecularly imprinted polymer, nucleic acid hybridization, enzyme recognition, and click chemistry, and amplification strategies in food safety and contaminant analysis are described in detail. The future development of the application of glucose meters in food safety supervision is also discussed.

Can portable glucose and lactate meters be a useful tool in quantifying stress of juvenile Chinook salmon?

Blood plasma analyses can provide researchers, aquaculture facilities and fisheries managers with valuable insights into the physiological state and welfare of fish. For example, glucose and lactate are part of the secondary stress response system, and elevated concentrations are indicators of stress. However, analysing blood plasma in the field can be logistically difficult and typically involves sample storage and transport to quantify concentrations in a laboratory setting. Portable glucose and lactate meters offer an alternative to laboratory assays and have shown to be relatively accurate in fish, but these tools have only been validated for a few fish species. The objective of this study was to investigate if portable meters could be reliably used in Chinook salmon (Oncorhynchus tshawytscha). As part of a larger stress response study, juvenile Chinook salmon (157 ± 17mm fork length [mean ± standard deviation; SD]) were exposed to stress-inducing treatments and sampled for blood. Laboratory reference glucose concentrations (milligrams per deciliter; mg/dl; n = 70) were positively correlated with the Accu-Check Aviva meter (Roche Diagnostics, Indianapolis, IN) measurements (R2 = 0.79), although glucose values were 1.21 ± 0.21 (mean ± SD) times higher in the laboratory than with the portable meter. Lactate concentrations (milliMolar; mM; n = 52) of the laboratory reference were also positively correlated (R2 = 0.76) with the Lactate Plus meter (Nova Biomedical, Waltham, MA) and were 2.55 ± 0.50 times higher than portable meter. Our results indicate both meters could be used to measure relative glucose and lactate concentrations in Chinook salmon and provide fisheries professionals with a valuable tool, particularly in remote field settings.