Paper-based analytical devices are fluidic chips fabricated with extremely inexpensive materials, namely paper, thereby allowing their use as a zero-cost analytical device in third-world countries that lack access to expensive diagnostic infrastructures. The aim of this review is to discuss: (1) microfluidic paper-based analytical devices (microPADs) for quantitative analysis, (2) fabrication of two- or three-dimensional microPADs, (3) analytical methods of microPADs, and (4) our opinions regarding the future applications of microPADs for quantitative urinalysis.
Developing Countries ; Methods ; Microfluidics ; Urinalysis*

Electrophoresis, Gel, Two-Dimensional ; methods ; Humans ; Proteomics ; methods ; Urinalysis ; methods

OBJECTIVETo establish a detection method for trimethyltin chloride in urine by the Head space-GC.

METHODAfter derivatizing trimethyltin chloride, the urines was separated by the head space-gc, and then the trimethyltin chloride detected qualitatively and quantificationally.

RESULTSIn the concentration range of 0.02 ∼ 0.40 mg/L urinary trimethyltin chloride, showed a quadratic, r = 0.9992, detection limit was 0.005 mg/L, the relative standard deviation was 1.9% ∼ 2.5%, recovery was 92.0% to 100%, the urine samples can be saved at least 90 days in -18°C refrigerator.

CONCLUSIONThe instrument, reagents involved in the detection require low, the operations to processing samples are simple, high sensitivity, less interference, good reproducibility, and suitable for quantitative and qualitative analysis, convenient to promotion.

Chromatography, Gas ; methods ; Humans ; Trimethyltin Compounds ; urine ; Urinalysis ; methods

In this paper is proposed a new method to solve the segmentation of the complicated defocusing urinary sediment image. The main points of the method are: (1) using wavelet transforms and morphology to erase the effect of defocusing and realize the first segmentation, (2) using adaptive threshold processing in accordance to the subimages after wavelet processing, and (3) using 'peel off' algorithm to deal with the overlapped cells' segmentations. The experimental results showed that this method was not affected by the defocusing, and it made good use of many kinds of characteristics of the images. So this new mehtod can get very precise segmentation; it is effective for defocusing urinary sediment image segmentation.
Algorithms ; Humans ; Image Interpretation, Computer-Assisted ; Urinalysis ; methods ; Urine

A new urine analysis core module based on high performance 32-bit microprocessor and high precision color sensor was presented. A novel optical structure and a specific circuit were applied to improve measurement precision and temperature was used to compensate for results in this core module. The information of urine test peice, such as all original data and color RGB value, reflectivity, semi-quantitative level, etc. can be output. The results showed that the measuring precision was about 95% or above with ideal stability and reliability using this presented core module, which can be conveniently applied in various urine analyzers, and can greatly decrease the cost of urine analyzers in development and production.
Color ; Equipment Design ; Microcomputers ; Reproducibility of Results ; Temperature ; Urinalysis ; instrumentation ; methods

Chromatography, Reverse-Phase ; methods ; Humans ; Sorbic Acid ; analogs & derivatives ; analysis ; Urinalysis ; methods

The biochemical analysis of urine is an important inspection and diagnosis method in hospitals. The conventional method of urine analysis covers mainly colorimetric visual appraisement and automation detection, in which the colorimetric visual appraisement technique has been superseded basically, and the automation detection method is adopted in hospital; moreover, the price of urine biochemical analyzer on market is around twenty thousand RMB yuan (Y), which is hard to enter into ordinary families. It is known that computer vision system is not subject to the physiological and psychological influence of person, its appraisement standard is objective and steady. Therefore, according to the color theory, we have established a computer vision system, which can carry through collection, management, display, and appraisement of color difference between the color of standard threshold value and the color of urine test paper after reaction with urine liquid, and then the level of an illness can be judged accurately. In this paper, we introduce the Urine Test Biochemical Analysis method, which is new and can be popularized in families. Experimental result shows that this test method is easy-to-use and cost-effective. It can realize the monitoring of a whole course and can find extensive applications.
Automation ; Colorimetry ; methods ; Diagnosis, Computer-Assisted ; Humans ; Signal Processing, Computer-Assisted ; Urinalysis ; methods

Arsenic ; urine ; Chromatography, High Pressure Liquid ; methods ; Formamides ; analysis ; Humans ; Urinalysis ; methods

OBJECTIVEWe aimed to establish a sensitive quantified method for the simultaneous determination of melamine and cyanuric acid residues in water and urine by hydrophilic interaction liquid chromatography coupled with electrospray tandem mass spectrometry (HILIC-ESI-MS/MS) with the pretreatment of hydrophilic functional silica gel and cation exchange resin mixed solid phase extraction column(MCT), and to investigate the melamine and cyanuric acid residues in 501 water and 216 urine from several province and city.

METHODSAbout 100 ml water (or 10 ml urine) was adjusted to pH 3.0 with concentrated hydrochloric acid, and then mixed with the internal standard solution((15)N3-melamine and (15)N3-(13)C3 -cyanuric acid) and 100 ml acetonitrile (10 ml for urine). The solution was cleaned with MCT solid-phase extraction column, and eluted once by 3 ml methanol and twice by 2.5 ml methanol (containing 5% ammonia water). The effluent was collected and dried by N2 flow at 40 °C, and then diluted to 2 mmol/L ammonium acetate containing 90% volume fraction acetonitrile. The completely dissolved solution was then filtered with 0.22 µm organic membrane; and the filtrate was detected by high performance liquid chromatography-tandem mass spectrometry and quantified with internal standards. The repeatability and sensitivity of the assay were evaluated. Then we detected the melamine and cyanuric acid residues in 501 water and 216 urine samples collected from several province and city.

RESULTSBy the quantification of internal standard (15)N3-melamine and (15)N3-(13)C3-cyanuric acid, the melamine and cyanuric acid were linear in the range of 2.0-1000.0 µg/L with correlation coefficient of 0.9998 and 0.9997. The detection limits of the method were separately 0.4 ng/L (melamine) and 0.3 ng/L (cyanuric acid) for water, and 4.0 ng/L (melamine) and 3.0 ng/L (cyanuric acid) for urine. The average recovery rate was around 95.3%-100.1% with the relative standard deviation (RSD) was <4.02%. Out of the 501 water samples, melamine was detected out in 19.9% (100/501) and cyanuric acid was detected out in 5.2% (26/501). The content was around 0.03-5.00 g/L. Melamine or cyanuric acid was detected out in 24.5% of the urine samples (53/216), with the content around 0.01-1.00 g/L.

CONCLUSIONThe established method of solid phase extraction-hydrophilic interaction liquid chromatography-electrospray tandem mass spectrometry can satisfy the requirement for detection of melamine and cyanuric acid residues in all sorts of water and urine. Meanwhile, the two substances widely existed in water and Chinese population.

Chromatography, Liquid ; methods ; Environmental Monitoring ; methods ; Humans ; Mass Spectrometry ; Solid Phase Extraction ; methods ; Triazines ; analysis ; urine ; Urinalysis ; methods

Two types of urine dipstick assays, Multistix-SG and Comber-9-Test RL, were compared for compatibility, accuracy, specificity and predictive values of a positive and negative test in 501 patients' urine and artificially prepared specimen. We found that the results of semiquantitative tests of Multistix-SG and Comber-9-Test RL performed were statistically similar in patients' specimen. The urinary leukocyte esterase tests of Comber-9-Test RL assays compared with urine sediment microscopy in regard to compatibility, sensitivity, specificity, and predictive values of a positive and negative test 83.7%, 48.1%, 90.3%, 47.4% and 90.1%, respectively. The urinary nitrite tests of Comber-9-Test RL assays compared with urine culture tests, in regard to compatibility, sensitivity, specificity, and predictive values of a positive and negative test were 90.3%, 19.4%, 84.7%, 53.8% and 94.1, respectively. For the urinary protein, the sulfosalicylic acid method was the most sensitive test for any kinds of protein, and Multistix-SG appeared more sensitive than Comber-9-Test RL for the albuminuria. For the urinary bilirubin and glucose, two dipstick assays were similar in their diagnostic efficiency. Finally in the urinary occult blood tests, Comber-9-Test RL assays was more sensitive than Multistix-SG.
Albuminuria ; Bilirubin ; Glucose ; Leukocytes ; Methods ; Microscopy ; Occult Blood ; Sensitivity and Specificity ; Urinalysis