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A novel assay platform consisting of a finger pump microchip (FPM) and a WiFi-based analytical detection platform is presented for measuring the concentration of methylparaben (MP) in commercial foods. In the presented approach, a low quantity (5 μL) of distilled food sample is dripped onto the FPM and undergoes a modified Fenton reaction at a temperature of 40 °C to form a green-colored complex. The MP concentration is then determined by measuring the color intensity (RGB) of the reaction complex using APP software (self-written) installed on a smartphone. The color intensity Red(R) + Green(G) value of the reaction complex is found to be linearly related (R

An electrochemical-biosensor (EC-biosensor) microchip consisting of screen-printed electrodes and a double-layer reagent paper detection zone impregnated with amaranth is proposed for the rapid determination of microalbuminuria (MAU) in human urine samples. Under the action of an applied deposition potential, the amaranth is adsorbed on the electrode surface and the subsequent reaction between the modified surface and the MAU content in the urine sample prompts the formation of an inert layer on the electrode surface. The inert layer impedes the transfer of electrons and hence produces a drop in the response peak current, from which the MAU concentration can then be determined. The measurement results obtained for seven artificial urine samples with known MAU concentrations in the range of 0.1–40 mg/dL show that the measured response peak current is related to the MAU concentration with a determination coefficient of R2 = 0.991 in the low concentration range of 0.1–10 mg/dL and R2 = 0.996 in the high concentration range of 10–40 mg/dL. Furthermore, the detection results obtained for 82 actual chronic kidney disease (CKD) patients show an excellent agreement (R2 = 0.988) with the hospital analysis results. Overall, the results confirm that the proposed detection platform provides a convenient and reliable approach for performing sensitive point-of-care testing (POCT) of the MAU content in human urine samples.

Lab-on-paper, or microfluidic paper-based analytical devices (μPADs), use paper as a substrate material, and are patterned with a system of microchannels, reaction zones and sensing elements to perform analysis and detection. The sample transfer in such devices is performed by capillary action. As a result, external driving forces are not required, and hence the size and cost of the device are significantly reduced. Lab-on-paper devices have thus attracted significant attention for point-of-care medical diagnostic purposes in recent years, particularly in less-developed regions of the world lacking medical resources and infrastructures. This review discusses the major advances in lab-on-paper technology for blood analysis and diagnosis in the past five years. The review focuses particularly on the many clinical applications of lab-on-paper devices, including diabetes diagnosis, acute myocardial infarction (AMI) detection, kidney function diagnosis, liver function diagnosis, cholesterol and triglyceride (TG) analysis, sickle-cell disease (SCD) and phenylketonuria (PKU) analysis, virus analysis, C-reactive protein (CRP) analysis, blood ion analysis, cancer factor analysis, and drug analysis. The review commences by introducing the basic transmission principles, fabrication methods, structural characteristics, detection techniques, and sample pretreatment process of modern lab-on-paper devices. A comprehensive review of the most recent applications of lab-on-paper devices to the diagnosis of common human diseases using blood samples is then presented. The review concludes with a brief summary of the main challenges and opportunities facing the lab-on-paper technology field in the coming years.

Cyclamate is an artificial sweetener with high sweetness and low calories, and is a common sugar substitute for weight control and diabetic patients. However, excessive cyclamate consumption is associated with various health disorders, and hence it is prohibited as a food additive in many countries around the world. The current research proposes a light-shading reaction microfluidic PMMA/paper detection (MPD) system for determining the cyclamate concentration in food. In the current system, inject 10 μL of the extracted sodium cyclamate sample into the sample chamber of the MPD device, perform the diazotization reaction under shading conditions, and then suck it into the detection area through a paper strip, which consists of a paper chip embedded with modified Bratton-Marshall reagent. Once the paper chip is thoroughly wetted, the MPD device is inserted into a microanalysis box, where a fuchsia azo reaction compound is produced through heating at 40 °C for 3 min. The reaction complex is observed by a camera and the reaction image is wirelessly transmitted to a smartphone, and the concentration of sodium cyclamate is measured through the self-developed grayscale software. The results obtained for the sodium cyclamate samples with a concentration in the range of 50-1000 ppm show that the measured gray value changes linearly with the sodium cyclamate concentration, and the correlation coefficient (R

For most of the fast screening test papers for detecting Hg2+, the obtained results are qualitative. This study developed an operation for the μPAD and combined it with the chemical colorimetric method. Silver nanoparticle (AgNP) colloids were adopted as the reactive color reagent to combine and react with the Hg standards on the paper-based chip. Then, the RGB values for the color change were used to establish the standard curve (R2 > 0.99). Subsequently, this detection system was employed for the detection tests of actual samples, and the detected RGB values of the samples were substituted back to the formula to calculate the Hg2+ contents in the food. In this study, the Hg2+ content and recovery rate in commercially available packaged water and edible salts were measured. The research results indicate that a swift, economical, and simple detection method for Hg2+ content in food has been successfully developed.

Silver nanoparticles (AgNPs) have stable reactivity and excellent optical absorption properties. They can be applied in various industries, such as environmental protection, biochemical engineering, and analyte monitoring. However, synthesizing AgNPs and determining their appropriate dosage as a coloring substance are difficult tasks. In this study, to optimize the process of AgNP synthesis and obtain a simple detection method for trace mercury in the environment, we evaluate several factors—including the reagent addition sequence, reaction temperature, reaction time, the pH of the solution, and reagent concentration—considering the color intensity and purity of AgNPs as the reaction optimization criteria. The optimal process for AgNP synthesis is as follows: Mix 10 mM of silver nitrate with trisodium citrate in a hot water bath for 10 min, then, add 10 mM of sodium borohydride to produce the AgNPs and keep stirring for 2 h, finally, adjust the pH to 12 to obtain the most stable products. For AgNP-based mercury detection, the calibration curve of mercury over the concentration range of 0.1–2 ppb exhibits good linearity (R2 &gt, 0.99). This study provides a stable and excellent AgNP synthesis technique that can improve various applications involving AgNP-mediated reactions and has the potential to be developed as an alternative to using expensive detection equipment and to be applied for the detection of mercury in food.

In recent years, microfluidic lab-on-paper devices have emerged as a rapid and low-cost alternative to traditional laboratory tests. Additionally, they were widely considered as a promising solution for point-of-care testing (POCT) at home or regions that lack medical infrastructure and resources. This review describes important advances in microfluidic lab-on-paper diagnostics for human health monitoring and disease diagnosis over the past five years. The review commenced by explaining the choice of paper, fabrication methods, and detection techniques to realize microfluidic lab-on-paper devices. Then, the sample pretreatment procedure used to improve the detection performance of lab-on-paper devices was introduced. Furthermore, an in-depth review of lab-on-paper devices for disease measurement based on an analysis of urine samples was presented. The review concludes with the potential challenges that the future development of commercial microfluidic lab-on-paper platforms for human disease detection would face.

Due to the sparsity in knowledge, we investigated the presence of various estrogenic endocrine-disrupting chemicals (EEDCs), including phthalates (PAEs), bisphenol-A (BPA), and nonylphenol (NP), as well as microplastics (MPs) in samples of the most widely consumed fish collected from different estuaries in northern Taiwan. We then proceeded to determine the likely contribution that this exposure has on the potential for health impacts in humans following consumption of the fish. Six hundred fish caught from five river estuaries (producing 130 pooled samples) were analyzed to determine how different factors (such as the river, benthic, pelagic, and migratory species) influence EEDCs’ contamination and the possible impacts on human health following typical consumption patterns. The predominant EEDCs was diethyl phthalates (DEP), bis (2-ethylhexyl) phthalates (DEHP), and di-iso-nonylphthalate (DINP) in fish, present at 52.9 ± 77.3, 45.3 ± 79.8, and 42.5 ± 79.3 ng/g dry weight (d.w.), respectively. Residual levels of NP, BPA, and MPs in the fish were 17.4 ± 29.1 and 1.50 ± 2.20 ng/g d.w. and 0.185 ± 0.338 mg/g d.w., respectively. EEDCs and MPs levels varied widely among the five river estuaries sampled due, in part, to differences in habitat types and the associated diversity of fish species sampled. For DEP, the Lao-Jie River and pelagic environments produced the most severely contaminated fish species, respectively. DEP residues were also associated with the burden of MPs in the fish. Based on our analysis, we predict no substantial direct human health risk by EEDCs based on typical consumption rates of estuarine fish by the Taiwanese people. However, other sources of EEDC exposure cannot be ignored.

Milk is a necessity for human life. However, it is susceptible to contamination and adulteration. Microfluidic analysis devices have attracted significant attention for the high-throughput quality inspection and contaminant analysis of milk samples in recent years. This review describes the major proposals presented in the literature for the pretreatment, contaminant detection, and quality inspection of milk samples using microfluidic lab-on-a-chip and lab-on-paper platforms in the past five years. The review focuses on the sample separation, sample extraction, and sample preconcentration/amplification steps of the pretreatment process and the determination of aflatoxins, antibiotics, drugs, melamine, and foodborne pathogens in the detection process. Recent proposals for the general quality inspection of milk samples, including the viscosity and presence of adulteration, are also discussed. The review concludes with a brief perspective on the challenges facing the future development of microfluidic devices for the analysis of milk samples in the coming years.

A multifunctional microchip-based distillation apparatus is presented for the distilled of sulfur dioxide (SO2) in food products. The microchip is fabricated on poly(methyl methacrylate) (PMMA) substrates, and comprises a sample zone, a buffer zone, a serpentine distillation column, and a collection zone. In the process, the sample is introduced into the sample zone and is heated under carefully controlled temperature and time conditions. The resulting SO2 and water vapor are carried by nitrogen (N2) gas to the distillation column, where the SO2 is separated from the water vapor via the condensing effects of a continuous cold water flow. Finally, the SO2 is transported to the collection zone, where it is collected with hydrogen peroxide (H2O2) and its concentration determined using an alkali-based titration and paper-based detection method. A distillation efficiency of 90.5% is obtained under the optimal distillation conditions at concentrations of 20–4000 ppm. Moreover, a linear correlation (R2 = 0.9997) is observed between the experimental measurements of the SO2 concentration and the known concentration. The validity of the presented microchip-based distillation apparatus is further investigated by distilling the SO2 concentrations of 25 commodity samples. The detection results show that the deviation does not exceed 5.4% compared with the traditional official method.

Insulator-based dielectrophoresis has to date been almost entirely restricted to Newtonian fluids despite the fact that many of the chemical and biological fluids exhibit non-Newtonian characteristics. We present herein an experimental study of the fluid rheological effects on the electroosmotic flow of four types of polymer solutions, i.e., 2000 ppm xanthan gum (XG), 5% polyvinylpyrrolidone (PVP), 3000 ppm polyethylene oxide (PEO), and 200 ppm polyacrylamide (PAA) solutions, through a constriction microchannel under DC electric fields of up to 400 V/cm. We find using particle streakline imaging that the fluid elasticity does not change significantly the electroosmotic flow pattern of weakly shear-thinning PVP and PEO solutions from that of a Newtonian solution. In contrast, the fluid shear-thinning causes multiple pairs of flow circulations in the weakly elastic XG solution, leading to a central jet with a significantly enhanced speed from before to after the channel constriction. These flow vortices are, however, suppressed in the strongly viscoelastic and shear-thinning PAA solution.

A rapid analytical platform composed of a paper-based chip (µPB-Chip) and a small analytic box is developed to determine the concentration of human serum albumin (HSA). In this study, a Bromocresol Green (BCG) reagent is dropped into the reaction area of the µPB-Chip, and the HSA concentration was derived from the R (red) value intensity of the albumin-BCG complex formed after a reaction process at 37 °C for 12 min. The effectiveness of the developed method is displayed using albumin concentrations ranging from 0 to 5 g/dL in HSA control samples. The measurement results acquired from 36 volunteer patient’s HSA samples are presented to be in good consistency with those obtained utilizing a conventional assay technique (R2 = 0.9912). Ultimately, the results show that the developed platform provides a convenient, economical and dependable method for HSA concentration detection.

A method is proposed for determining the concentration of albumin (ALB) in human whole blood samples using a 3-dimensional (3D) microfluidic paper-based chip and a smart detection module. In fabricating the paper-based chip, the reaction area is implanted with bromocresol green (BCG) reagent and the device is stored in a nitrogen (N2) environment at a temperature of —15 °C until needed for use. In the detection process, 10 μl of whole blood is dropped onto the entrance area of the chip and the plasma within the sample diffuses through a separation channel into the reaction zone. A reaction is induced between the ALB in the plasma and the BCG reagent in the reaction area by heating the chip at 37 °C for 6 min. The ALB concentration is then detected using a colorimetry technique implemented on a cell phone in the form of a self-written app. It is shown that the detection results obtained for 40 pure ALB samples and 30 whole blood samples are consistent with those obtained using a traditional spectrophotometry method (R2 = 0.9837 and R2 = 0.9968). The proposed detection system thus provides a reliable tool for practical ALB determination purposes.

A magnetic field measurement system based on an array of Hall sensors is proposed. The sensors are fabricated using conventional microelectromechanical systems (MEMS) techniques and consist of a P-type silicon substrate, a silicon dioxide isolation layer, a phosphide-doped cross-shaped detection zone, and gold signal leads. When placed within a magnetic field, the interaction between the local magnetic field produced by the working current and the external magnetic field generates a measurable Hall voltage from which the strength of the external magnetic field is then derived. Four Hall sensors are fabricated incorporating cross-shaped detection zones with an identical aspect ratio (2.625) but different sizes (S, M, L, and XL). For a given working current, the sensitivities and response times of the four devices are found to be almost the same. However, the offset voltage increases with the increasing size of the detection zone. A 3 × 3 array of sensors is assembled into a 3D-printed frame and used to determine the magnetic field distributions of a single magnet and a group of three magnets, respectively. The results show that the constructed 2D magnetic field contour maps accurately reproduce both the locations of the individual magnets and the distributions of the magnetic fields around them.

A microfluidic colorimetric detection (MCD) platform consisting of a sliding hybrid PMMA/paper microchip and a smart analysis system is proposed for the convenient, low-cost and rapid analysis of human urine and whole blood samples. The sliding PMMA/paper microchip comprises a PMMA microfluidic chip for sample injection and transportation, a paper strip for sample filtration (urine) or separation (blood), and a sealed paper-chip detection zone for sample reaction and detection. In the proposed device, the paper-chip is coated with bicinchoninic acid (BCA) and biuret reagent and is then assembled into the PMMA microchip and packaged in aluminum housing. In the detection process, the PMMA/paper microchip is slid partially out of the housing, and 2 μL of sample (urine or whole blood) is dripped onto the sample injection zone. The chip is then slid back into the housing and the sample is filtered/separated by the paper strip and transferred under the effects of capillary action to the sealed paper-chip detection zone. The housing is inserted into the color analysis system and heated at 45 °C for 5 min to produce a purple-colored reaction complex. The complex is imaged using a CCD camera and the RGB color intensity of the image is then analyzed using a smartphone to determine the total protein (TP) concentration of the sample. The effectiveness of the proposed method is demonstrated using TP control samples with known concentrations in the range of 0.03–5.0 g/dL. The detection results obtained for 50 human urine samples obtained from random volunteers are shown to be consistent with those obtained from a conventional hospital analysis system (R2 = 0.992). Moreover, the detection results obtained for the albumin (ALB) and creatine (CRE) concentrations of 50 whole blood samples are also shown to be in good agreement with the results obtained from the hospital analysis system (R2 = 0.982 and 0.988, respectively).

An integrated microfluidic Au nanoparticle (AuNP) aptasensor device is proposed for monitoring the concentration of potassium (K

Sodium dehydroacetate (NADH) has good antibacterial effects and is widely used as a preservative in dairy products. However, NADH is toxic in large amounts, so it must be added to food in accordance with regulations. Accordingly, the current study has developed a microfluidic analysis detection (MAD) system for the determination of NADH in foods incorporating a microfluidic PMMA-paper chip and a smart analysis device. In this system, the extracted NADH sample is dropped into the sample chamber of the microfluidic PMMA-paper chip and is then wicking/filtering through paper strips and transferred to a detection zone embedded with Fe-Alum reagent. The chip is heated at 35 °C for 5 min to produce a compound reaction and the color compound image acquired by a camera is then transmitted wirelessly to a smartphone, where the NADH concentration is obtained by the intensity inversion of RGB analysis. A standard calibration curve is determined using NADH control samples with concentrations in the range of 30–5000 ppm. The feasibility of the proposed MAD system is then evaluated by analyzing the NADH concentrations of 15 commercial dairy products. It is shown that the measured values deviate from those obtained using an official high performance liquid chromatography (HPLC) method by no more than 5.0%.

This review reports on recent advances in state-of-the-art detection methods for microfluidic paper-based analytical devices (μPADs). The review commences by describing the materials, fabrication methods and driving mechanisms employed in μPADs. The review then explores the main detection methods and applications of μPADs proposed over the past five years. The discussions focus on seven detection technologies, namely (1) colorimetric detection, (2) fluorescent detection, (3) electrochemical detection and photoelectrochemical detection, (4) chemiluminescent detection, (5) electrochemiluminescent detection, (6) nanoparticle-based detection, and (7) spectrometry detection. Overall, the review provides a useful insight into recent advances in the μPAD detection field and serves as a useful source of reference for further research and innovation in the field.

An integrated platform consisting of a three-dimensional (3-D) microfluidic paper-based analytical device (µPAD) and a portable detection system is proposed for the determination of human whole blood creatinine. In the proposed detection method, the reaction region of the 3-D µPAD is implanted with picric acid and NaOH reagent and allowed to dry. Whole human blood is then dripped onto the inlet region of the chip and the blood plasma diffuses through the separation channel into the reaction zone under the effects of capillary action. The µPAD is heated at a temperature of 37 °C for 5 min to induce a Jaffe reaction between the creatinine in the blood plasma and the reagent. Finally, the creatinine concentration is detected using a colorimetric method. The validity of the proposed approach is demonstrated using control samples with creatinine concentrations ranging from 0.19 to 7.64 mg/dL. The detection results obtained for 40 real-world human serum creatinine samples and 30 real-world whole blood samples are shown to be in excellent agreement with those obtained using a conventional macroscale assay technique. Overall, the results show that the proposed platform provides a compact, low-cost and reliable approach for whole blood creatinine concentration detection.

Modern microflow cytometers are sophisticated instruments capable of measuring multiple physical characteristics of a single cell simultaneously as the cells flow in suspension through a measuring device. Cytometers are the tool of choice for the high-speed acquisition and analysis of large single cell populations. However, traditional devices lack the ability to provide intracellular spatial information. In the past few decades, various flow cytometer systems with the ability to combine cell/particle detection and the acquisition of two or three-dimensional spatial information have been proposed. However, these devices suffer a number of drawbacks Accordingly, the problem of developing more sophisticated microflow cytometers based on electrical impedance, optical detection and image analysis methods has received significant attention in the literature. This review describes some of the major advances made in the microfluidic cytometry field over the past ten years. The review focuses specifically on recent proposals for enhanced microfluidic focusing techniques and detection/analysis methods, respectively. Overall, the review provides a useful insight into the microflow cytometer technology field for both new and existing users.

This paper presents a review of the current state-of-the-art in micropumping technology for biomedical applications. The review focuses particularly on the actuation schemes, flow directing methods and liquid chamber configurations used in the devices proposed over the past five years. A comparative study is presented of the various mechanical and non-mechanical micropumps proposed for biomedical applications. The performance of the various devices is compared in terms of their actuation voltage, power consumption, operating frequency range, flow rate, backpressure, and so forth. The basic operating principles and advantages of each method are introduced, and their limitations described where appropriate. The review provides a useful source of reference for selecting micropumping schemes capable of meeting the specific flow rate requirements of different biomedical applications. In general, the review is expected to be of interest to both seasoned researchers and practitioners in the micropumping and biomedical technology fields and those entering the field for the first time.

Micromixers are crucial components within micro biomedical systems. This article presents a comprehensive review of the main state-of-the art applications of micromixers in biomedical systems over the past ten years. The article commences by reviewing the fundamental fluidic behaviors involved in microfluidic mixing. The biomedical applications of micromixers are then described in regard to their use particularly for (1) sample concentration, (2) chemical synthesis, (3) chemical reaction, (4) polymerization, (5) extraction and purification, (6) biological analysis, and (7) droplet/emulsion processes and others. The review concludes with a brief statistical analysis of the published literature in the micromixer field and an overview of the relative advantages of passive micromixers compared to active micromixers.

An integrated microfluidic loop-mediated isothermal amplification (LAMP) platform consisting of a microfluidic chip and a portable operating system is proposed for koi herpesvirus (KHV) detection applications. The microfluidic chip is fabricated using a CO2 laser system and comprises a sample chamber, two reagent chambers, a mixing chamber, a serpentine channel, a reaction chamber, and three flow rectifiers based on PDMS membranes. The main components of the operating system include a power source, a time relay, a microfluidic chip holder, four gas pressure valves, a microheater, and a temperature controller. In the proposed detection method, the KHV sample and LAMP reagent are loaded into the sample and reagent chambers, respectively, and are mixed under the effects of an external gas pressure driving force. The mixed solution is then heated at a temperature of approximately 63 °C for 60 min in order to replicate the KHV sample. Finally, the replicated sample is mixed with SYBR Green I dye in order to facilitate fluorescence-based KHV detection. The feasibility of the proposed microfluidic platform is confirmed by comparing the detection results obtained for a sample containing 10 ng/μL KHV with those obtained using a gel electrophoresis PCR-based method. The experimental results shows that the proposed LAMP platform has a KHV detection limit of around 3 × 10−2 ng/μL. Overall, the results presented in this study show that the proposed microfluidic platform provides a compact, reliable and portable tool for KHV detection purposes.

An integrated platform consisting of a microfluidic paper-based analytical device (μPAD) and a portable detection system is proposed for low concentration formaldehyde (CH 2 O) detection. In the proposed approach, the reaction zone of the μPAD is coated with ammonium acetate (AA) and acetoacetanilide (AAA) indicator and is dried at 40 °C for 30 min. The formaldehyde sample is then dripped on the reaction zone and the μPAD is transferred to a hot plate in the portable detection system. A Hantzsch reaction is induced by heating the μPAD at 30 °C for 10 min. The resulting fluorescent formaldehyde-Acetoacetanilide complex (dihydropyridine derivative) is observed by a CMOS camera and the color image is transferred to a smartphone by means of a connector. Finally, the CH 2 O concentration is derived using self-written RGB color analysis mobile software implemented on the phone. The experimental results obtained using control samples with known CH 2 O concentrations in the range of 0.2–2.5 ppm show that the B (blue) fluorescence intensity (Y) and formaldehyde concentration (X) are related as Y = 29.455 X + 117.64. Moreover, the correlation coefficient is equal to R 2 = 0.9937. The real-world applicability of the proposed detection platform is demonstrated by measuring the CH 2 O concentration in twelve commercial food samples. It is shown that the concentration measurements obtained using the proposed system deviate by no more than 6.2% from those obtained using a conventional spectrophotometric technique. Overall, the results presented in this study show that the proposed integrated microfluidic paper-based system provides a compact and reliable tool for low concentration CH 2 O measurement purposes.

An integrated platform consisting of a microfluidic paper-based chip and a mini-box detection system is proposed for the concentration detection of formaldehyde. In the proposed approach, the reaction region of the paper-based chip is implanted with Acetoacetanilide reagent, and the formaldehyde concentration is deduced from the UV light-induced fluorescence intensity of the formaldehyde-Acetoacetanilide complex (dihydropyridine) produced in a Hantzsch reaction process at room temperature for 2 min. The experimental results obtained using control samples with formaldehyde concentrations ranging from 0 to 8 ppm show that the formaldehyde concentration (Y) and fluorescence intensity (X) are related as Y = 0.0039 e0.058X. Moreover, the correlation coefficient (R2) is equal to 0.9987. The real-world applicability of the proposed paper-based platform is demonstrated by measuring the formaldehyde concentration in eleven commercial food samples. It is found that the measurement results deviate from those obtained using a standard bench top method by no more than 4.7%. Overall, the results presented in this study show that the proposed system provides a rapid and reliable technique for formaldehyde concentration detection.

Cadmium exposure is associated with chronic kidney disease (CKD), but the optimal biomarker for early cadmium-associated nephrotoxicity in low-level exposure has not yet been established. We conducted a cross-sectional investigation involving 167 CKD patients stratified according to tertiles of urinary cadmium levels (UCd), in which enzyme-linked immunosorbent assay (ELISA)-measured novel renal biomarkers were utilized to assess the extent of renal injury associated with cadmium burden. In the analyses, urinary kidney injury molecule-1 (KIM-1) levels and age were the independent factors positively correlated with UCd after adjusting for covariates in non-dialysis-dependent CKD patients (high vs. low UCd, odds ratio (95% confidence interval), 1.0016 (1.0001–1.0032), p = 0.043, and 1.0534 (1.0091–1.0997), p = 0.018). Other conventional and novel renal biomarkers, such as serum creatinine, estimated glomerular filtration rate, CKD staging, urinary protein/creatinine ratio, urinary 8-hydroxy-2-deoxyguanosine (8-OHdG), and urinary epidermal growth factor (EGF) were not independently correlated with UCd in the analyses. In conclusion, our study found that the ELISA-measured urinary KIM-1 level could serve as an early renal injury marker in low-level cadmium exposure for non-dialysis-dependent CKD patients. In addition, age was an independent factor positively associated with UCd in this population.

Artificial sweeteners are often used by food manufacturers as a low-calorie alternative to sugar. However, an excessive consumption of artificial sweeteners can be harmful to human health. Consequently, their concentration in foods and beverages must be carefully controlled. The current study therefore proposes a microfluidic chromatography detection (MCD) system for the simultaneous concentration determination of two common sweeteners, namely saccharin sodium (SAC) and acesulfame potassium (Ace-K). In the proposed system, the sample is dropped on the MCD chip with a developing solution consisting of DI water, ethyl acetate, acetic acid and ethanol the chip is then placed in a UV microanalysis device. After allowing sufficient time for the developing solution to separate the SAC and Ace-K sweeteners from the interfering substances, the chip is illuminated by a 254-nm ultraviolet lamp and captured by a CMOS camera. Then wirelessly transfer the captured image to a smartphone, where the Ace-K or SAC sweetener concentration is derived using self-developed chromatography analysis app on the smartphone. Results obtained using control samples with known SAC and Ace-K concentrations show that the current MCD system provides a reliable detection performance for both sweeteners over the concentration range of 50 ~ 2000 ppm. Furthermore, the detection results of the concentrations of SAC and Ace-K in 16 commercial food samples are within 6.3% of the results obtained using traditional macroscale HPLC systems.