52 results about "Lactate concentration" patented technology

Disclosed herein is a fully-integrated, disposable biochip for point-of-care testing of clinically relevant parameters. Specifically, in accordance with an embodiment of the present invention, the biochip is designed for POCT (point-of-care-testing) of an array of metabolic parameters including partial pressure of oxygen, Glucose, and Lactate concentration from venous blood samples. The biochip is fabricated on a low-cost plastic substrate using mass manufacturing compatible fabrication processes. Furthermore, the biochip contains a fully-integrated metallic micro-needle for blood sampling. The biochip also uses smart passive microfluidics in conjunction with low-power functional on-chip pressure generators for microfluidic sequencing. The design, configuration, assembly and operation of the biochip are ideally suited for a disposable biochip specifically targeted towards POCT applications.

The invention discloses a new technology for separating and purifying L-lactic acid with continuous ion exchange, membrane separation and molecular distillation. Centrifuged and decolorated lactic acid fermentation liquid is pumped into an ultrafiltration apparatus to remove proteins; clear liquid with a lactate concentration of 10-50g/L is then pumped into a continuous ion exchange system filled with anion exchange resin for adsorption; an inorganic salt solution with a concentration of 0.001-0.2M is used for impurity washing and an acid solution with a concentration of 0.1-2M is used for elution; nano-filtration technology is employed for synchronous concentration and desalination of the ion exchange eluent; high-purity and high-quality L-lactic acid can be obtained after treatment with molecular distillation means in the end. The technology has the advantages of low equipment investment, strong continuous operability, low production cost, high product purity, easy scale production, etc.

A blood test method including (a) centrifuging a mammalian blood sample into a plasma and blood cells; (b) removing buffy coats from the blood cells to obtain red blood cells containing solutes confined therewithin; (c) washing the red blood cells with a buffered physiological saline solution and isolating the washed blood cells; (d) mixing the washed red blood cells with a buffered physiological saline solution to obtain a suspended liquid; (e) centrifuging the suspended liquid to remove a supernatant and to obtain a red blood layer; (f) mixing the red blood layer with a hypertonic solution and maintaining the resulting suspension at a temperature of 25 to 40° C. for a period of time sufficient for the solutes confined in the red blood cells to penetrate into the hypertonic solution; (g) centrifuging the suspension to obtain a supernatant containing the solutes; and (h) measuring the supernatant for at least one factor selected from a glucose concentration, a pyruvic acid concentration, a lactic acid concentration and an oxidation-reduction potential.

The invention discloses a method for detecting blood lactic acid in vitro by using a chemiluminescence method, which is characterized in that LD is utilized to catalyze L-lactic acid and NAD<+> to generate pyruvate and NADH, the pyruvate and ADP generate ATP under the catalysis of pyruvate kinase (PK), ATP and glycerol generate glycerol-3-phosphoric acid and ADP under the catalysis of GK, the glycerol-3-phosphoric acid is acted by GPO to obtain H2O2, and H2O2 is catalyzed by HPR to enable luminol to emit light; the size of light signals is in positive correlation with the concentration of thepyruvate, i.e. the bigger the concentration of the lactic acid is, the stronger the emitted light signals are; the concentration of the lactic acid can be conjectured by recording the light signals; and the lactic acid with the known concentration is used for detecting the light signals to make a dose-response curve, and the content of the lactic acid of an unknown sample can be calculated throughthe curve. In the invention, a chemiluminescence substance replaces a colored substance to achieve the purposes of sensitivity, stability, wide range and safety. The method can be used for preparinga corresponding commercial kit for quantitatively detecting the lactic acid in body fluids such as whole blood, plasma, cerebrospinal fluid, urine, gastric juice and the like.

The invention provides a slow-release antibacterial acellular matrix biological material and a preparation method thereof. The preparation method comprises the following steps: S1, providing a biological tissue, and carrying out decellularization and virus inactivation treatment on the biological tissue; S2, performing plasma treatment on the treated biological tissue to modify the surface of the biological tissue to obtain an acellular matrix; S3, soaking the acellular matrix in a slow-release antibacterial aqueous solution containing an organic slow-release medium, an antibacterial agent and weak acid, so that the organic slow-release medium is loaded on the surface of the acellular matrix, the antibacterial agent is loaded on the surface of the organic slow-release medium, the weak acid is dilute acetic acid, dilute hydrochloric acid or dilute lactic acid, and the concentration of the weak acid is 0.01-1 mol/L; and S4, taking out the soaked acellular matrix, and performing vacuum freeze drying and sterilization to obtain the slow-release antibacterial acellular matrix biological material.

A device and method for automatically and repeatedly measuring fetal Lactic Acid (LA) concentration in the blood, for monitoring fetal stress. The device is connected by a probe to the scalp of the fetus and measures the Lactic Acid concentration in the blood at preset intervals. The device is optionally provided with an alarm which is activated when lactic acid concentration is outside a preset normal range.

The microdialysis technique and device of the present invention can be used to study metabolic aspects of human and animal organs. When a microdialysis catheter is for example placed into the substance of a beating heart, there is always concern for problems with the catheter position. Further, there is always a risk for damage to heart tissue as well as to the catheter. The present invention is designed to avoid such damages, and a study has confirmed that data obtained from the epicardial probe of the present invention reflects the state of the myocardial metabolism. In anesthetized normoventilated pigs (n=20), a sternotomy was performed and a Gore-tex suture snare was placed around a branch of the left anterior descending (LAD) artery. One microdialysis probe was inserted in the myocardial tissue supplied by the snared LAD branch. Another microdialysis probe was placed on the epicardial surface above the myocardial probe. The protocol included four, ten minute ischemic periods (intervention group) followed by a forty minute ischemic period. The control group was only exposed to a forty minute ischemic period. It was possible to place the microdialysis probes of the present invention on the epicardial surface, and to recover samples reflecting the myocardial metabolic state of the heart. It was also possible to measure rapid changes in concentrations especially for lactate, where ischemia periods as short as ten minutes resulted in detectable increases. A similar pattern was found when analysing glucose and glycerol concentrations in paired samples. Data obtained from the device and method of the present invention, placed on the epicardial surface showed a similar pattern compared to data from a standard probe placed in the myocardium. Thus, the epicedial application of the present invention is useful for perioperative monitoring during cardiac surgery.

A lactate sensor capable of accurately measuring a lactate concentration in a short period of time. The lactate sensor includes an insulating substrate, an electrode system including at least a working electrode and a counter electrode provided on the substrate, and a reagent layer provided on the electrode system. The reagent layer contains lactate oxidase, it mediator, and N-(2-acetamide)-2-aminoethanesulfonic acid.

The method is for monitoring a childbirth process of a pregnant woman. In a measuring step, a lactate concentration of vaginal fluids is measured. In a comparison step, it is determined if the measured lactate concentration is greater than a predetermined lactate concentration that indicates that amniotic fluid has passed from an amnion of the pregnant woman. In a measuring step, the lactate concentration is measured. In a comparison step, it is determined if the measured lactate concentration is greater than a lactate threshold interval. When the lactate concentration is less than the lactate threshold interval the pregnant woman is stimulated in a stimulating step to give birth.

The full blood lactic acid biosensor modified with oriented carbon nanotube features that one layer of Co particles as the catalyst for oriented growth of carbon nanotube is deposited on the substrate and that the reaction layer has base layer comprising oriented carbon nanotube as the second electric intermediate and the upper layer comprising L-lactic oxidase and the mixture of reagent, stabilizer and buffering liquid as the first electric intermediate. Compared with available the technology, the present invention has the advantages of obviously raised responding sensitivity on lactic acid concentration of the sensor, work voltage of the sensor lowered from 500 mv to 300 mv, no need of pre-treatment of the blood sample and blood sample amount as less as 2 microliter.

The invention relates to a kit for diagnosing/mensurating D-lactic acid by utilizing the technologies of the enzymatic cycling amplification method, the enzymic colorimetric method and the enzyme linked immunosorbent assay (ELISA) based on the specificity of the D-lactic acid. The invention further relates to a method, a principle and the composition and the components of a reagent for mensurating the concentration of the D-lactic acid, and belongs to the technology field of medical/food inspection and measurement. The main components of the kit include a buffer solution, reduced coenzyme, 2-ferricytochrome-c, ammonia ions, D-lactate dehydrogenase, alanine dehydrogenase, glycine oxidase, peroxidase, a reduced chromogen combination and a stabilizer. Through a series of enzymatic reactions, the colorless reduced chromogen combination is finally oxidized into colored dyes, thereby mensurating the content of the dyes at 400nm-700nm of the wavelength by utilizing a visible light analyzer and further reflecting the concentration of the D-lactic acid directly.

The invention relates to a kit for diagnosing/mensurating D-lactic acid by utilizing the technologies of the enzymatic cycling amplification method, the enzymic colorimetric method and the enzyme linked immunosorbent assay (ELISA) based on the specificity of the D-lactic acid. The invention further relates to a method, a principle and the composition and the components of a reagent for mensurating the concentration of the D-lactic acid, and belongs to the technology field of medical/food inspection and measurement. The main components of the kit include a buffer solution, reduced coenzyme, 2-ferricytochrome-c, ammonia ions, D-lactate dehydrogenase, alanine dehydrogenase, glycine oxidase and a stabilizer. Through mixing a sample and the reagent by a certain volume ratio, a series of enzymatic reactions occur, then the reactant is placed under an ultraviolet/visible light analyzer, and the degree/velocity of the decrease in absorbance at 340nm of the dominant wavelength is detected, thereby mensurating the concentration of the D-lactic acid.

Disclosed herein are genetically engineered hematopoietic cells, which express one or more lactate-modulating factors (e.g., polypeptides), and optionally a chimeric receptor polypeptide (e.g., an antibody-coupled T cell receptor (ACTR) polypeptide or a chimeric antigen receptor (CAR) polypeptide) capable of binding to a target antigen of interest. Also disclosed herein are uses of the engineered hematopoietic cells for inhibiting cells expressing a target antigen in a subject in need thereof.

The invention provides a method for sterilization of campylobacter on a whole-chicken slaughtering processing production line. The method can safely and effectively lower the quantity of the campylobacter on the surface of chicken, but not reduce the quality of the chicken. According to the method disclosed by the invention, lactic acid is adopted to process the whole chicken, wherein the optimal anti-bacterial conditions are as follows: the concentration of lactic acid is 0.19%, the soaking processing time is 17 minutes, and the soaking processing temperature is 20.9 DEG C. By adopting the method disclosed by the invention, the quantity of the campylobacter on the surface of the chicken processed by lactic acid reaches a lower level, and meanwhile the quality of the chicken is not influenced. Compared with the traditional disinfection method, the method is safer, more efficient and lower in influence on the chicken quality.

The invention relates to a kit for diagnosing/mensurating D-lactic acid by utilizing the technology of the enzymic colorimetric method based on the specificity of the D-lactic acid. The invention further relates to a method, a principle and the composition and the components of a reagent for mensurating the concentration of the D-lactic acid, and belongs to the technology field of medical/food inspection and measurement. The main components of the kit include a buffer solution, coenzyme, D-lactate dehydrogenase and a stabilizer. Through mixing a sample and the reagent by a certain volume ratio, a series of enzymatic reactions occur, then the reactant is placed under an ultraviolet/visible light analyzer, and the degree/velocity of the increase in absorbance at 340nm of the dominant wavelength is detected, thereby mensurating the concentration of the D-lactic acid.

The invention relates to a ratiometric fluorescent probe for visually and quantitatively detecting lactic acid and application of the ratiometric fluorescent probe. The preparation method of the ratiometric fluorescent probe comprises the following steps that: a bCDs/AgNPs nano-composite of silver nanoparticle-coated doped blue fluorescent carbon dots is prepared, and blue fluorescence of bCDs isquenched due to aggregation and the doping of AgNPs; and combining the bCDs/AgNPs nano composite with quantum dots for red fluorescenceemission to form the bCDs/AgNPs-rQDs ratiometric fluorescent probe. The lactic acid generates H2O2 under the action of lactate oxidase, the H2O2 etches the AgNPs to form silver ions; the structure of the compound is damaged to recover blue fluorescence of the bCDs,the formed silver ions quench the red fluorescence of the rQDs, and therefore, the ratio (I445/I645) of fluorescence intensity of the probe changes along with the change of the concentration of the lactic acid, and the change of the ratio of the fluorescence intensity of the probe can cause obvious change of fluorescence color, and therefore, visual detection is realized. The ratiometric fluorescent probe is used for quantitatively determining biomolecules in serum and is high in sensitivity and simple in detection.