The invention relates to a luminescence-based recipe and device using the same. More particularly, the invention relates to one-step, luminescence-based recipes for the measurement of creatinine, urea, uric acid, or glucose, and device using the same.
Biochemical analysis of small molecules is a routine procedure for health examination. Based on the analysis, physiological functions such as kidney, liver, or cardiovascular functions of a patient can be assessed by a physician. Present analysis is mainly based on absorbance or fluorescence which requires a specific light source and is not suitable for household or personal applications. Luminescence analysis is highly sensitive and relatively simple in design, and more particularly, most physiological markers or metabolites can be detected by luminescence analysis. Luminescence analysis can be, therefore, used in the development of fast analysis platform, or in the combination of optical sensors and micro-electro-mechanical system (MEMS) to design a portable physiological detector for personal health management.
The present luminescence-based physiological detector requires large amount of samples and can not be easily manipulated by non-professional persons. In addition, the difficulties of serum separation, matrix interference, sensitivity, reproducibility, and simplified machinery design are still problems to be solved. It is, therefore, still a need to develop one-step luminescence analysis and device for multiple analysts.
Accordingly, luminescence-based recipes for the measurement of creatinine, urea, uric acid, or glucose are provided.
An embodiment of the luminescence-based recipe for the measurement of creatinine comprises 0.01˜150 U/mL of creatininase, 0.01˜150 U/mL of creatine kinase, 1×10−6˜5×10−2 mg/mL of firefly luciferase, 0.1˜5000 μM of luciferin, 1 μM˜20 mM of MgSO4, 0.1˜5000 μM of ATP, 0˜1% of BSA, 0˜50 mM of DTT (1,4-dithioerythritol)), and 5˜200 mM of buffer at pH6˜8.
An embodiment of the luminescence-based recipe for the measurement of urea comprises 0.01˜100 U/mL of urea amidolyase (URL), 1×10−6˜5×10−2 mg/mL of firefly luciferase, 0.1˜5000 μM of luciferin, 1 μM˜20 mM of MgSO4, 0.1˜5000 μM of ATP, 0˜100 mM of KCl, 0˜100 mM of NaHCO3, 0˜20 mM of EGTA, 0˜1% of BSA, 0˜50 mM of DTT (1,4-dithioerythritol)), and 5˜200 mm of buffer at pH6˜8.
An embodiment of the luminescence-based recipe for the measurement of glucose comprises 0.1˜10 mM of luminol, 0.01˜500 U/mL of horse redish peroxidase (HRP), 0.01˜500 U/mL of glucose oxidase (GOx), 0˜10 mM of PIP, 0˜1% of Triton X-100, 0˜20 mM of EDTA, and 5˜200 mM of buffer at pH6˜8.
An embodiment of the luminescence-based recipe for the measurement of uric acid comprises 0.1˜10 mM of luminol, 0.01˜500 U/mL of HRP, 0.01˜500 U/mL of uricase, 0˜10 mM of PIP, 0˜1% of Triton X-100, 0˜20 mM of EDTA, and 5˜200 mM of buffer at pH6˜8.
A device using the above recipes is also provided. The device comprises a centrifugal unit and a luminescence analyzer and is characterized in that the centrifugal unit includes a rotary cylinder, and a rotation motor for exerting a centrifugal force for the rotary cylinder, wherein the rotary cylinder includes an inner surface and an interconnected outer surface, the outer surface has a plurality of radially extended openings, wherein the luminescence analyzer is disposed corresponding to one of the extended openings.
Embodiments of the invention can be more fully understood and further advantages become apparent when reference is made to the following description and the accompanying drawings in which:
Luminescence-based recipes and device using the same are provided.
Luminescence assay has sensitivity of hundred or thousand times than spectroscopic or colorimetric assays and is relatively easy in manipulation. In particular, most physiological markers or metabolites can be measured by luminescence assay. Luminescence can be, therefore, used in the development of fast analysis platform. Luminescence emission is produced when an electron falls from an excited state which is induced by chemical or biological reaction to a ground state. Luminescence emission can be classified as chemiluminescence and bioluminescence. The mechanism of the reactions is shown as below.
Oxidation of Luminol
Enzyme Catalyzed Decomposition of 1,2-dioxetanes
Oxidation of Acridinium Ester
Oxidation of Aryl Oxalates
Firefly Luciferin-Luciferase Reaction
Marine Bacterial Luciferin-Luciferase Reaction
Aequorin Reaction
Chemiluminescence utilizes compounds such as luminol, 1,2-dioxetane, acridinium esters, and oxalate esters, or their derivatives where luminol is the most common. The emission mechanism of luminol is the oxidation in the presence of peroxides, usually hydrogen peroxide with an emission length of 450 nm. The reaction can be catalyzed by enzymes such as horseradish peroxidase, micro-peroxidase, catalase, or other substances such as hemoglobin, cytochrome c, Fe(III), and other metal complexes. The emission can be amplified by enhancers such as phenols, naphthols, amines to promote the sensitivity. Bioluminescence includes firefly luciferase, bacteria luciferase, and aequorin. Among these, luciferin-luciferase derived from firefly and marine bacteria are well-known and are with emission length of 580 nm and 450 nm respectively. Accordingly, chemiluminescence analysis is applied for analysts related to oxidation-reduction reaction, and bioluminescence analysis is applied for analysts related to ATP or NAD(P) reaction. One detector is adequate for varies reactions since the emission is in the range of visible light. In addition, these reactions are the most important mechanism for various enzyme-substrate reactions and can be applied in a wide field. Related application has been reported, for example, Rauch et al discloses a chemiluminescent assay using flow injection analysis system with luminol for the detection of choline or phospholipase D; Michel et al. discloses a three-enzyme detection system using bacteria luciferase for the detection of D-sorbitol with sensitivity of 50 nM in 4-6 ml; Eu et al. discloses a firefly luciferase system with ATP competition for the detection of galactose.
In addition to having high sensitivity, luminescence analysis does not require excitation light source, filter, or electrodes since it only detects photons. Moreover, background interference will not occur since no fluorescence is emitted. Luminescence analysis has wide dynamic range of up to 5 decades, significantly reducing the complexity of sample pretreatment. The analysis is appropriate for quick detection since the emission is completed in few seconds. Present luminometer adopts photomultiplier tube (PMT) or avalanche photodiode (APD) as the detector and is equipped with signal processing system and sample bearing device, which is relatively simple and suitable for miniaturization to achieve portable purpose.
Kidney is an important organ for excreting waste and redundant water. Urine production is a complicated excretion and resorption process for the balance of electrolytes and pH. In addition, kidney also produces hormones and vitamins for normal functions of a body. Acute and chronic renal failure is always of concern and the development of a portable detector for renal function is necessary.
The assessment of renal function can not be done with a single indicator, but needs multiple analysts. The indicators for clinical use now mainly include blood urea nitrogen (BUN) and creatinine. BUN is released by the catabolism of amino acids and 60% of BUN is excreted by kidney. The increase of BUN indicates abnormal protein metabolism, acute glomerulonephritis, uremia, or urinary obstruction. The increase of creatinine may due to severe muscular disease, nephritis, or hyperthyroidism. The amount of creatinine in urine may provide representative creatinine clearance for the calculation of glomerular filtration rate (GFR) (Tietz N. W. (1970) Fundamentals of Clinical Chemistry, W.B. Sauders Company: USA, 5th edition, pp. 419). In addition, uric acid is the final product of the metabolism of purine and the increase of uric acid in blood indicates gout, renal failure, dehydration, metabolic acidosis, or excess purine uptake. A study from Australia shows that diabetics especially type II has 36% possibility of renal complication. Except for blood glucose control, monitoring of blood pressure and renal function is also important for diabetics in order to prevent diabetic nephropathy (MacIsaac R. J., et al. (2004) Nonalbuminuric Renal Insufficiency in Type 2 Diabetes. Diabetes Care. 27, 195-200). Accordingly, the simultaneous detection of BUN, creatinine, uric acid, and glucose is helpful for the evaluation and monitoring of renal function. Table 1 shows the normal range, analysis mechanism, detection time, and physiological significance of the four analysts.
1obtained from Chema Diagnostica.
2estimated from the performance of Boehringer Mannheim/Hitachi 917 analyzer.
3Detection range (sensitivity) and standard deviation are Abs. = 10−3 and 10%, respectively. The exact sensitivity could be worse and limited.
The inventors developed luminescence-based recipes for the measurement of creatinine, urea, uric acid, or glucose with one-step reaction. The recipes can be used in an aqueous solution or lyophilized powder and are the most appropriate formula for the detection of trace analysts in a few amounts of sample with a stable and reliable sensitivity and a wide detection range.
Accordingly, one embodiment of the luminescence-based recipe for the measurement of creatinine includes 0.01˜150 U/mL of creatininase, 0.01˜150 U/mL of creatine kinase, 1×10−6˜5×10−2 mg/mL of firefly luciferase, 0.1˜5000 μM of luciferin, 1 μM˜20 mM of MgSO4, 0.1˜5000 μM of ATP, 0˜1% of BSA, 0˜50 mM of DTT (1,4-dithioerythritol)), and 5˜200 mm of buffer at pH6˜8.
The other embodiment of the luminescence-based recipe for the measurement of creatinine in solution form includes 0.4˜75 U/mL of creatininase, 0.01˜75 U/mL of creatine kinase, 5×10−4˜2×10−2 mg/mL of firefly luciferase, 5˜2000 μM of luciferin, 1 μM˜500 μM of MgSO4, 0.5˜1000 μM of ATP, 0˜0.5% of BSA, 0˜40 mM of DTT, and 25˜50 mM of buffer at pH6˜8.
Another embodiment of the luminescence-based recipe for the measurement of creatinine in lyophilized form includes 5˜100 U/mL of creatininase, 5˜100 U/mL of creatine kinase, 0.1˜3×10−22 mg/mL of firefly luciferase, 5˜2000 μM of luciferin, 1 μM˜500 μM of MgSO4, 0.5˜1000 μM of ATP, 0˜0.5% of BSA, 0˜40 mM of DTT, and 25˜50 mM of buffer at pH6˜8.
Yet another embodiment of the luminescence-based recipe for the measurement of serum creatinine in lyophilized form includes 0.4˜75 U/mL of creatininase, 0.01˜75 U/mL of creatine kinase, 0.1˜3×10−2 mg/mL of firefly luciferase, 5˜2000 μM of luciferin, 1 μM˜500 μM of MgSO4, 0.5˜1000 μM of ATP, 0˜0.5% of BSA, 0˜40 mM of DTT, and 25˜50 mM of buffer at pH6˜8.
The buffer used for the luminescence-based recipe for the measurement of creatinine includes, but is not limited to, Gly-gly buffer, HEPES, Tris, Bis-Tris, Bis-Tris propane, MOPS, PIPES, phosphate, or borate, preferably Gly-gly buffer at pH 7.5.
One embodiment of the luminescence-based recipe for the measurement of urea includes 0.01˜100 U/mL of urea amidolyase (URL), 1×10−6˜5×10−2 mg/mL of firefly luciferase, 0.1˜5000 μM of luciferin, 1 μM˜20 mM of MgSO4, 0.1˜5000 μM of ATP, 0˜100 mM of KCl, 0˜100 mM of NaHCO3, 0˜20 mM of EGTA, 0˜1% of BSA, 0˜50 mM of DTT (1,4dithioerythritol)), and 5˜200 mM of buffer at pH6˜8.
The other embodiment of the luminescence-based recipe for the measurement of urea in solution form includes 0.1˜50 U/mL of urea amidolyase (URL), 5×10−4˜2×10−2 mg/mL of firefly luciferase, 5˜2000 μM of luciferin, 1 μM˜5 mM of MgSO4, 0.5˜1000 μM of ATP, 0˜40 mM of KCl, 0˜40 mM of NaHCO3, 0˜10 mM of EGTA, 0˜0.5% of BSA, 0˜40 mM of DTT (1,4-dithioerythritol)), and 25˜50 mM of buffer at pH6˜8.
Another embodiment of the luminescence-based recipe for the measurement of urea in lyophilized form includes 0.1˜50 U/mL of urea amidolyase (URL), 0.1˜3×10−2 mg/mL of firefly luciferase, 5˜2000 μM of luciferin, 1 μM˜5 mM of MgSO4, 0.5˜3000 μM of ATP, 0˜40 mM of KCl, 0˜40 mM of NaHCO3, 0˜10 mM of EGTA, 0˜0.5% of BSA, 0˜40 mM of DTT (1,4-dithioerythritol)), and 25˜50 mM of buffer at pH6˜8.
Yet another embodiment of the luminescence-based recipe for the measurement of serum urea in lyophilized form includes 0.1˜50 U/mL of urea amidolyase (URL), 0.1˜3×10−2 mg/mL of firefly luciferase, 5˜2000 μM of luciferin, 1 μM˜5 mM of MgSO4, 0.5˜1000 μM of ATP, 0˜40 mM of KCl, 0˜40 mM of NaHCO3, 0˜10 mM of EGTA, 0˜0.5% of BSA, 0˜40 mM of DTT (1,4-dithioerythritol)), and 25˜50 mM of buffer at pH6˜8.
The buffer used for the luminescence-based recipe for the measurement of urea includes, but is not limited to, Gly-gly buffer, HEPES, Tris, Bis-Tris, Bis-Tris propane, MOPS, PIPES, phosphate, or borate, preferably Gly-gly buffer at pH 7.5.
One embodiment of the luminescence-based recipe for the measurement of glucose includes 0.1-10 mM of luminol, 0.01˜500 U/mL of horse redish peroxidase (HRP), 0.01˜500 U/mL of glucose oxidase (GOx), 0˜10 mM of PIP, 0˜1% of Triton X-100, 0˜20 mM of BETA, and 5˜200 mM of buffer at pH6˜9.
The other embodiment of the luminescence-based recipe for the measurement of glucose in solution form includes 0.1˜5 mM of luminol, 0.01˜10 U/mL of horse redish peroxidase (HRP), 0.1˜200 U/mL of glucose oxidase (GOx), 0˜2 mM of PIP, 0˜0.1% of Triton X-100, 0˜5 mM of EDTA, and 25˜50 mM of buffer at pH6˜9.
Another embodiment of the luminescence-based recipe for the measurement of glucose in lyophilized form includes 0.1˜5 mM of luminol, 0.1˜10 U/mL of horse redish peroxidase (HRP), 0.1˜200 U/mL of glucose oxidase (GOx), 0˜2 mM of PIP, 0˜0.1% of Triton X-100, 0˜5 mM of EDTA, and 25˜50 mM of buffer at pH6˜9.
Yet another embodiment of the luminescence-based recipe for the measurement of serum glucose in lyophilized form includes 0.1˜5 mM of luminol, 0.1˜250 U/mL of horse redish peroxidase (HRP), 1-200 U/mL of glucose oxidase (GOx), 0˜2 mM of PIP, 0˜0.1% of Triton X-100, 0˜5 mM of EDTA, and 25˜50 mM of buffer at pH6˜9.
The buffer used for the luminescence-based recipe for the measurement of glucose includes, but is not limited to, Gly-gly buffer, HEPES, Tris, Bis-Tris, Bis-Tris propane, MOPS, PIPES, phosphate, or borate, preferably Gly-gly buffer at pH 7.5.
One embodiment of the luminescence-based recipe for the measurement of uric acid includes 0.1˜10 mM of luminol, 0.01˜500 U/mL of HRP, 0.01˜500 U/mL of uricase, 0˜10 mM of PIP, 0˜1% of Triton X-100, 0˜20 mM of EDTA, and 5˜200 mM of buffer at pH6˜9.
The other embodiment of the luminescence-based recipe for the measurement of uric acid in solution form includes 0.1˜5 mM of luminol, 0.01˜20 U/mL of HRP, 0.1˜100 U/mL of uricase, 0˜2 mM of PIP, 0˜0.1% of Triton X-100, 0˜5 mM of EDTA, and 25˜100 mM of buffer at pH6˜9.
Another embodiment of the luminescence-based recipe for the measurement of uric acid in lyophilized form includes 0.1˜5 mM of luminol, 0.1˜10 U/mL of HRP, 0.1˜100 U/mL of uricase, 0˜2 mM of PIP, 0˜0.1% of Triton X-100, 0˜5 mM of EDTA, and 25˜50 mM of buffer at pH6˜9.
Yet another embodiment of the luminescence-based recipe for the measurement of serum uric acid in lyophilized form includes 0.1˜5 mM of luminol, 0.1˜200 U/mL of HRP, 0.1˜100 U/ml of uricase, 0˜2 mM of PIP, 0˜0.1% of Triton X-100, 0˜5 mM of EDTA, and 25˜50 mM of buffer at pH6˜9.
The buffer used for the luminescence-based recipe for the measurement of uric acid includes, but is not limited to, Gly-gly buffer, HEPES, Tris, Bis-Tris, Bis-Tris propane, MOPS, PIPES, phosphate, or borate, preferably Gly-gly buffer at pH 8.5.
A device using the above recipes is also provided. The device comprises a centrifugal unit and a luminescence analyzer and is characterized in that the centrifugal unit includes a rotary cylinder, and a rotation motor for exerting a centrifugal force for the rotary cylinder, wherein the rotary cylinder includes an inner surface and an interconnected outer surface, the outer surface has a plurality of radially extended openings, the luminescent unit is disposed corresponding to one of the extended openings.
The embodiment of the device provides quick analysis for multiple analytes and is miniaturized for testing small amounts of sample, easy manipulation, dynamic measurement, and simultaneous analysis.
Practical examples are described herein.
Materials and Methods
Materials:
Table 2 shows chemicals used in the examples.
Equipments
A. Luminometer:
Type and factory: TD-20/20, Turner BioSystems
Setup: sensitivity is 47%.
Accessories: 8×50 mm testing tube(PP)
Or the luminescent analyzer of the invention.
B. Lyophilizer:
Type and factory: Heto Drywinner FD-3, JOUAN
Parameters: temperature of the compressor is −50° C. and vacuum is 0.5 hPa.
Procedures:
Preparation of the Embodiments of Chemiluminescent Recipes
The master mixture was prepared in accordance with the table listed below. Ten or twenty μl of the master mixture was placed into the testing tube. The master mixture was added into the sample and the RLU value was recorded at appropriate time by a luminometer when the test was performed in solution form. When the test was performed in lyophilized form, sample was added into the testing tube containing the lyophilized master mixture and the RLU value was recorded at appropriate time by the luminometer.
Lyophilization
The differences between blank and sample containing analytes should be determined by the master mixture. The determination of the master mixture was confirmed by the luminometer. Ten or twenty μl of the master mixture was placed into a testing tube and the solution was frozen in liquid nitrogen for 20 sec. The testing tube was placed in a Heto Drywinner for 6 hours for the lyophilization of the master mixture. The testing tube was then stored at 4° C. in dark.
The Amount Range of the Analytes and Algorithm Thereof
S: determination of analyte in buffer by solution form
L: determination of analyte in buffer by lyophilization powder
P: determination of analyte in plasma by lyophilization powder
Creatinine analysis is illustrated as an example. The mechanism of luminescence-based analysis includes three steps: (1) creatinine is converted to creatine by creatininase; (2) creatine is phosphorized by creatine kinase with consumption of ATP; (3) the concentration of creatinine in the system is determined by ATP competition compared with firefly luciferase-luciferin system. The reactions are shown as below.
The present detector for multiple analytes may not be reliable when applied for sample in small amount volume, however, small amount of sample is the key point for portable detector. In addition, the detection ranges for different analytes are various, for example, the normal range for blood glucose is between 0.6˜6.7 mM, but for other analytes may be below sub-mM, for example, the normal range for uric acid is between 0.14˜0.42 mM. A broad detection range is, therefore, required in addition to micro-detection.
Sample obtained by blood taking needle can be tens μl of blood, and the reaction volume in the system is about 10 μl. The requirement of small amount sampling can be achieved by the embodiment of the system of the invention. The present biosensor for the detection of creatinine is mainly through electrochemical mechanism with the problem of weak sensitivity or serious matrix interference (Soldatkin A. P., et al. (2002) Creatinine sensitive biosensor based on ISFETs and creatinine deiminase immobilized in BSA membrane. Talanta 58, 352-357) and cannot be applied in practice. In the contrary, the embodiment of the system of the invention overcomes these problems is shown in
The detection of creatinine, urea, uric acid, and glucose is shown below.
A. Detection of Creatinine in Solution Form
The detection was performed according to the materials and methods as described above and the recipes listed in table 4. Twenty μL of the master mixture was added to each tube and 1 μL of creatinine solution was introduced. The results are shown as
B. Detection of Creatinine in Lyophilized Form
The detection was performed according to the materials and methods as above described and the recipes listed in table 5. Twenty μL of the master mixture was added to each rube and 20 μL of creatinine solution was introduced. The results are shown as
C. Detection of Serum Creatinine in Lyophilized Form
The detection was performed according to the materials and methods as above described and the recipes listed in table 6. Twenty μL of the master mixture was added to each tube and 20 μL of creatinine solution was introduced. The results are shown as
A. Detection of Urea in Solution Form
The detection was performed according to the materials and methods as above described and the recipes listed in table 7. Ten μL of the master mixture was added to each tube and 0.5 μL of urea solution was introduced. The results are shown as
B. Detection of Urea in Lyophilized Form
The detection was performed according to the materials and methods as described above and the recipes listed in table 8. Five μL of the master mixture was added to each tube for lyophilization and the tube was stored at 4° C. in dark. The results are shown as
C. Detection of Serum Urea in Lyophilized Form
The detection was performed according to the materials and methods as described above and the recipes listed in table 9. Five μL of the master mixture was added to each tube for lyophilization and the tube was stored at 4° C. in dark. The results are shown as
A. Detection of Uric Acid in Solution Form
The detection was performed according to the materials and methods as above described and the recipes listed in table 10. Ten μL of the master mixture was added to each tube and 5 μL of uric acid solution was introduced. The results are shown as
B. Detection of Uric Acid in Lyophilized Form
The detection was performed according to the materials and methods as described above and the recipes listed in table 11. Ten μL of the master mixture was added to each tube for lyophilization and 10 μL of uric acid solution was then introduced. The results are shown as
C. Detection of Serum Uric Acid in Lyophilized Form
The detection was performed according to the materials and methods as described above and the recipes listed in table 12. Ten μL of the master mixture was added to each tube for lyophilization and 10 μL of serum spiked with different uric acid concentration was then introduced. The results are shown as
A. Detection of Glucose in Solution Form
The detection was performed according to the materials and methods as described above and the recipes listed in table 13. Ten μL of the master mixture was added to each tube and 1 μL of glucose solution was then introduced. The results are shown as
B. Detection of Glucose in Lyophilized Form
The detection was performed according to the materials and methods as above described and the recipes listed in table 14. Ten μL of the master mixture was added to each tube for lyophilization and 10 μL of glucose solution with different concentration was then introduced. The results are shown as
C. Detection of Serum Glucose in Lyophilized Form
The detection was performed according to the materials and methods as described above and the recipes listed in table 15. Ten μL of the master mixture was added to each tube for lyophilization and 10 μL of glucose solution with different concentration was then introduced. The results are shown as
While the invention has been described by way of example and in terms of preferred embodiment, it is to be understood that the invention is not limited thereto.
Number | Date | Country | Kind |
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93141719 | Dec 2004 | TW | national |