244results about How to "Sensitive method" patented technology

The present invention provides methods of diagnosing and monitoring systemic lupus erythematosus and drug-induced lupus erythematosus by measuring cell-based complement activation products in a subject's blood. In particular, the invention describes a diagnostic method employing the measurement of multiple complement activation products, such as C3d and C4d, on the surfaces of red blood cells, white blood cells, and platelets. Kits and automated systems for performing the methods of the invention are also disclosed.

The invention discloses a nucleic acid detection method comprising the following steps of determining an objective sequence to be detected and a target sequence to be detected; designing and synthesizing a padlock probe according to the objective sequence; preparing a rolling circle amplification primer; preparing a crosslinking probe; carrying out coupled reaction, and carrying out rolling circle amplification by utilizing the amplification primer through taking a coupled product as a template; after the rolling circle amplification is ended, detecting a rolling circle amplification product by using the crosslinking probe, and proving that the objective target sequence exists if a fluorescent signal is remarkably enhanced. A DNA (Deoxyribonucleic Acid) which can be detected by using a crosslinking probe detecting technology is amplified through the padlock probe and the rolling circle amplification reaction under the condition that a target to be detected exists, and no long-chain products can be detected by using the crosslinking probe detecting technology if no targets to be detected exist. One unit of sequence to be detected can be amplified to form hundreds of units of repetitive sequences through rolling circle amplification, and hundreds of times of signal amplification can be obtained on the basis of one unit of repetitive sequence by using the crosslinking probe detecting technology. The flexibility of the method disclosed by the invention is greatly enhanced.

The invention discloses a quantitative RT-PCR primer and probe and agent box of BCR-ABL fusing gene mRNA fluorescence with BCR-ABL fusing gene primer and probe sequence as SEQ ID NO1-4 and internal reference gene primer and probe sequence as SEQ ID NO5-7, wherein the agent box contains cell cracking liquid, water, RT-PCR reacting liquid, internal reference TBP RT-PCR reacting liquid, BCR-ABL fusing gene detecting probe, TBP internal reference gene testing probe, composite enzyme, standard material and comparing material; the box can test the expressive level of mRNA of P210BCR / ABL and P190BCR / ABL in the specimen, which provides the reference to diagnose, recurrent and treat chronic granulocytic leukemia and acute lymphocyte leukemia.

The invention discloses a method for rapidly measuring ethyl carbamate content in distilled liquor, belonging to the technical field of analysis measurement. In the invention, the impurities are removed by adopting rotary evaporation, the ethyl carbamate in a liquor sample is enriched by adopting headspace-solid phase microextraction technology, then gas chromatography-mass spectrum technology is adopted for conducting quantitative measurement, and the EC content in the liquor sample is calculated according to a standard curve. According to the method established in the invention, the ethyl carbamate in the distilled liquor can be detected rapidly and quantified accurately, the detection limit can be lowered to be 1.16mug / L, the linear correlation coefficient is more than 0.99, the recovery rate is 89%-119%, and the relative standard deviation is 1.26%-12.51%. In the method, a plurality of defects of in the original measuring method is overcome, the complicated pretreatment process and organic solvent are not needed, and the method is used for detection and quantitative analysis on the ethyl carbamate in the various distilled liquor with higher alcoholic strength.

The invention relates to a method for determining the content of astaxanthin in antarctic krill oil by chromatography, which comprises the steps of adopting a gel purification column with a BIO-3X packing, taking ethyl acetate and cyclohexane as eluant according to the proportion of 1:1, and collecting a fractions at 7.48-12.60min; carrying out low-temperature saponification in a solvent formed by methylene dichloride and methanol after purification, and completely converting astaxanthin esters to free astaxanthin; adopting a YMC-Carotenoid C30 chromatographic column; carrying out gradient elution by taking water solution of the methanol, methyl tert-butyl ether and 1% of phosphoric acid as a mobile phase; leading the flow rate to be 1.0mL / min, using an ultraviolet detector as the detector, and leading the detecting wavelength to be 474nm; and determining three isomers of the astaxanthin and adopting the sum of three peak areas for quantifying. The gel chromatographic column can better separate fat from the astaxanthin in the antarctic krill oil, and the adoption of the C30-reversed phase high performance liquid chromatography can accurately determine the content of the astaxanthin, thereby objectively and truly evaluating the quality of the antarctic krill oil.

The invention relates to a multiple PCR rapid detection method of common pathogen in mouth such as Actinobacillus actinomycetemcomitans, Bacterides forsythus, F. nucleatum and Porphyromones gingivalis and belongs to the field of molecular biology technology. The invention utilizes the multiple PCR to increase specific gene of Actinobacillus actinomycetemcomitans, Bacterides forsythus, F. nucleatum and Porphyromones gingivalis in mouth and utilizes electrophoresis to detect the specific gene. By designing the primers of Actinobacillus actinomycetemcomitans, Bacterides forsythus, F. nucleatum and Porphyromones gingivalis, the multiple PCR rapid detection method has the advantages of the uniform reaction condition, the sensitivity and the strong specificity of the method, the simultaneous detection and identification of the four bacteria in the specimen, accurate judgment of infection of different bacteria and greatly promoting the detection speed and the detection efficiency.

The invention discloses a building method of an HPLC characteristic chromatogram of radix paeoniae alba and a detection method of radix paeoniae alba. For a quality control problem of radix paeoniae alba, a sulfur-containing radix paeoniae alba HPLC characteristic chromatogram and a sulfur-free radix paeoniae alba HPLC characteristic chromatogram are built, and a high performance liquid chromatography-mass spectrometry analytic method is adopted to analyze and identify ingredients of sulfur-containing radix paeoniae alba and sulfur-free radix paeoniae alba. Whether radix paeoniae alba is fumigated with sulfur or not is judged by adopting the built HPLC characteristic chromatogram of radix paeoniae alba to identify a paeoniflorin sulfite product which is produced after dry sulphitation of radix paeoniae alba. Compared with a conventional sulfur dioxide detection method, the detection method provided by the invention is simple, high in sensitivity, strong in specificity and excellent inreproducibility, can be used for detecting whether radix paeoniae alba is fumigated with sulfur or not, therefore, can identify the authenticity and quality of radix paeoniae alba more comprehensively, accurately and quickly, and is particularly suitable for detecting and identifying large-scale production of radix paeoniae alba.

The invention discloses a turn-to-turn fault monitoring and protection identification method for a dry-type air-core series reactor of a parallel capacitor bank, and relates to the field of electricalequipment fault protection of a power system. At present, the understanding of triggering and exciting complex electromagnetic field energy conversion in the development process of the turn-to-turn short circuit fault of the capacitor bank parallel series reactor is lacked, and the turn-to-turn short circuit fault is not concerned to occur along with a secondary grounding fault. According to themethod, through acquiring bus PT voltage, acquiring CT three-phase current (Ia, Ib and Ic) of an angular inner sleeve of the angular wiring transformer or CT current I'a, I'b and I'c of a capacitor branch, HR (Iab), HR (Ibc) and HR (Ica) values or HR (I'a), HR (I'b) and HR (I'c) values are calculated in real time and mutual relations are identified. Fault identification and protection are realizedafter consistency identification of dominant frequency and reactance rate of harmonic current and bus grounding auxiliary signal identification, accurate identification and fault phase determinationcan be performed at the initial stage of turn-to-turn fault of equipment, and alarm and power supply cut-off can be performed in time.

The invention discloses amino acid sequences of GAI proteins of Pyrus betulaefolia and Pyrus bretschneideri, and nucleotide sequences for coding the GAI proteins, wherein the sequences are disclosed as SEQ ID NO1-4 in the sequence table. The invention also discloses a molecular identification method based on transfer of GAI mRNA between pear rootstock and scion, which comprises the following steps: (1) micrografting seedlings in test tubes by using Pyrus bretschneideri as scion and using Pyrus betulaefolia as rootstock; (2) looking for the respective specific enzyme-digestion sites of the GAI genes of the Pyrus bretschneideri and the Pyrus betulaefolia, and respectively designing a primer at the upstream and downstream of the enzyme-digestion site; (3) and carrying out enzyme-digestion on the Pyrus betulaefolia, the Pyrus bretschneideri, and the RT-PCR product of the Pyrus betulaefolia and the Pyrus bretschneideri after grafting, and comparing the enzyme-digestion spectra before and after the grafting to identify the transfer conditions. The method is quick, sensitive, accurate, simple and convenient, and is applicable to other pear plants.

A molecular diagnosing method for botrytis of tomato includes such steps as designing a pair of PCR primers specific to the pathogen of tomato botrytis, using them for PCR amplifying of the specimen to be tested, and judging if the tomato plant is suffered from botrytis. Its advantages are high speed, high sensitivity and high specificity.

The invention relates to a distinguishing method for Sudan dyes in red pepper and tomatoes, comprising the following steps of: pre-treating a red pepper sample, and then, extracting the pre-treated red pepper by using a mixture of alcohol, acetonitrile and isopropanol; then, placing the extracted red pepper into a water bath to be subjected to ultrasonic oscillation extraction; continuing to carry out oscillation extraction in a swing bed; carrying out vacuum concentration on filtrate obtained after filtering; redissolving the obtained residues by using the mixture of alcohol, acetonitrile and isopropanol; and filtering the obtained residues by using a polytetrafluoroethylene film with the size of 0.45mum to obtain a red pepper extracting liquid. A distinguished result is obtained through analysis by using a high-performance liquid chromatography (HPLC) and carrying out HPLC analysis on a standard sample of Sudan dyes. The method provided by the invention is sensitive; and the detecting limit of the Sudan dyes is only 1-5umg / g so that the method is very suitable for distinguishing whether Sudan dyes I-IV exist in melons, fruits and vegetables.

The invention discloses a method of determining micro calcium ions through dispersive liquid-liquid microextraction-Android mobile phone colorimetry. The method comprises the steps of taking glyoxalbishydroxyanil as a developer to react with the Ca ions in a borax-sodium hydroxide buffer solution with a pH (potential of hydrogen) of 12.8 to generate an orange hydrophobic complex, using tetradecylbenzyl dimethyl ammonium chloride as a surfactant, enriching and extracting the complex into a mixed extraction agent of trichloromethane and dichloromethane through a DLLME (dispersive liquid-liquidmicroextraction) technology, obtaining an RGB (red, green and blue) color intensity value of the solution through Android mobile phone software Color Grab, determining a quantitative relationship between color intensity of a sample and a Ca<2+> concentration, and obtaining a content of the calcium ions in the solution to be determined. The method is high in detection sensitivity and selectivity; amobile phone testing case is simple to operate and easy to carry; and the method can be deployed on site and is applicable to quick determination of ppb (part per billion) level calcium in water.

The invention provides a bioaerosol monitoring and early-warning method. The bioaerosol monitoring and early-warning method comprises the following steps: subjecting a bioaerosol to filtration so as to convert the bioaerosol into an aqueous solution sample; and then detecting biological particles non-specifically adsorbed on the sensitive surface of a sensor from the aqueous solution sample in real time by using the sensor which is sensitive to surface mass change. With the method, monitoring and early warning of the bioaerosol are realized, and bases are provided for subsequent identity detection and protection of the biological particles; and the method has wide application prospects.

The invention belongs to the field of product quality detection and in particular relates to a rapid detection method of residual amount of dimethylformamide in textiles. The method provided by the invention comprises the following steps of: preparing a guide sample and an internal standard solution; pre-treating the sample; extracting DMF (Dimethyl Formamide) in the sample; carrying out GC / MS (Gas Chromatograph / Metabolic Syndrome) analysis; and detecting the content of DMF through a standard addition method. The method provided by invention can be used for detecting the residual amount of DMF in products including leather, textiles, paper products and the like and various raw materials. Compared with the prior art, the method disclosed by the invention has the advantages of flexibility, accuracy, environment friendliness, simplicity, reliability and easiness of being popularized and is highly effective in detection of the residual amount of DMF in various products and raw materials.

The invention discloses a cutaneous sensitization detecting method based on a co-culturing mode of a three dimensional skin model and dendric cells. The cutaneous sensitization detecting method comprises the following steps : (1) preparing of the skin model in an early stage, (2) preparing and culturing of dendric cells, (3) constructing of co-culturing of the skin model and the dendric cells and exposing to-be-tested substances, (4) testing of activity of the skin model, (5) detecting of genome of the skin model, (6) detecting of secretion of lower layer cells of the co-culturing model, (7) detecting of expression of surface markers on the dendric cells, and (8) predicting of a statistic method and result. According to the cutaneous sensitization detecting method based on the co-culturing mode of the three dimensional skin model and the dendric cells, 3D skin which is reconstructed in vitro and has functions of barrier and metabolism and the dendric cells with the immunity function are combined together, a co-cultured novel experiment system is constructed and has similar functions and sensitization reaction with human bodies; the cutaneous sensitization of the to-be-tested substances can be evaluated from qualitative and quantitive aspects; and living animals and human bodies can be replaced through the method, and possible cutaneous sensitization caused by chemicals, cosmetics and drugs can be predicted directly.

The invention discloses a quantitative RT-PCR primer and probe and agent box of PML-RARa fusing gene mRNA fluorescence with BCR-ABL fusing gene primer and probe sequence as SEQ ID NO1-4 and internal reference gene primer and probe sequence as SEQ ID NO5-7, wherein the agent box contains cell cracking liquid, water, RT-PCR reacting liquid, internal reference G6PDHRT-PCR reacting liquid, BCR-ABL fusing gene detecting probe, G6PDH internal reference gene testing probe, composite enzyme, standard material and comparing material; the invention measures the expressive level of L-pattern, S-pattern and V-pattern mRNA simultaneously, rapidly and precisely, which improves inducing buffer rate and lessens early bleeding death.

The invention discloses a method for determining the content of soluble arsenic in a realgar-containing medicine and is characterized in that the method comprises the following steps of: (1) extracting soluble arsenic in the realgar-containing medicine by bionic solvent-ultrasonic treatment and / magnetic stirring; (2) alternatively purifying a solution obtained by extraction in the step (1); and (3) determining the content of soluble arsenic in the realgar-containing medicine by an ICP-MS method. The invention also discloses a method for determining the content of soluble valence-state arsenic in the realgar-containing medicine. By the adoption of the extraction mode for simulation in vivo, ICP-MS and HPLC-ICP-MS, the method for determining drug effects of realgar and main toxic components is established, and the method is sensitive and accurate.

The invention aims to provide a method for detecting contaminants in water employing mussel, namely, a method for detecting contaminants in aquatic water according to the change of content of glutathione transferases (GSTs) in the mussel. Compared with the existing instrument chemical methods, the method disclosed by the invention is lower in detection limit and more sensitive; confirmatory experiments all prove that the method disclosed by the invention is accurate, sensitive, simple to operate and good in repeatability; in the method, no toxic organic solvents or standard substances are used, the safety of an operator can be guaranteed well, and meanwhile, environmental pollution is reduced; detection time is shortened, detection cost is reduced, and the detection capability of a lab is effectively improved. Through deep study on the project, an internationally compatible food safety biological detection system is established.

The invention belongs to the product quality detection field, and concretely relates to a method for rapidly detecting the residual amount of benzene-based pollutants, such as benzene, toluene, ethylbenzene, xylene, styrene and the like, in plastic particles. The method concretely comprises the following steps: preparing a standard sample and an internal standard solution; pre-treating a sample; carrying out enriching extraction on benzene-based substances in the sample; carrying out GC / MS analysis; and determining the contents of the benzene-based substances through a standard addition method. The method disclosed in the invention can be used for detecting benzene-based volatile residues in products and a plurality of raw materials comprising color master batches, the plastic particles and the like. The method disclosed in the invention has the advantages of sensitivity, accuracy, environmental protection, simplicity, reliability and easy popularization, and is very effective in the determination of the benzene-based substances residual in a plurality of products and raw materials.

The invention belongs to the technical field of molecular biology, relates to analysis and detection for single nucleotide polymorphism, and in particular relates to a universal detection method. The detection method comprises the steps of amplifying target DNA (deoxyribonucleic acid) by gap-ligase chain reaction, introducing a DNAzyme sequence into a ligation product, degrading a phosphorylated probe which does not participate in the ligation reaction by Lambda excision enzyme, and releasing DNAzyme by excision enzyme III. The detection method is characterized in that a DNAzyme probe is combined with a Gap-LCR (ligase chain reaction) probe, and is characterized by comprising the following steps of: adding a section of DNAzyme sequence into a phosphorylated probe to be connected in an LCR system, adding an Anti-G sequence into a system (in complementary pairing with a DNAzyme sequence part in the probe) after the Gap-LCR amplification reaction stops, degrading a 5-end phosphorylated DNA probe by the Lambda excision enzyme, and releasing the DNAzyme in the ligation product by the excision enzyme III, thereby qualitatively and quantitatively detecting the SNP (single nucleotide polymorphism) due to the characteristics of the DNAzyme. The method is simple, convenient, practical and economical, and is widely applicable to the detection of various single nucleotide polymorphisms.

The invention discloses a gold / quantum dot nanometer probe for detecting activity ricin in complex substrates and an application of the gold / quantum dot nanometer probe. The gold / quantum dot nanometerprobe is prepared through the steps of forming deoxyribonucleotide double strands from gold nanometer particles modified by a deoxyribonucleotide single strand (ssODN) and quantum dots in a base pairing and hybridizing manner, and assembling the gold nanometer particles and the quantum dots into a kernel-satellite structure. The gold / quantum dot nanometer probe is used for detecting the activityricin, the detection limit is 7.46ng / mL, the accuracy is high, the reliability is good, and large-scale equipment and complex operation are not needed. In order to eliminate false positive further, the invention further provides a method for enriching the ricin in complex samples through magnetic microspheres. Under the condition that the concentration of the specific activity ricin does not needto be known, the gold / quantum dot nanometer probe provided by the invention can achieve naked eye visualized detection through quenched (Quenched) and switch on (Switch ON) of fluorescence.

The invention discloses a lysosomal targeting fluorescent probe and a preparation method thereof. A D-Pi-A-Pi-D (donor-Pi-receptor-Pi-donor)-type large Pi conjugated system is constructed by alpha, beta-unsaturated ketone as a receptor. Through intramolecular charge transfer, compared with the existing many fluorescent probes for lysosome, lysosomal targeting fluorescent probe can realize large red shift of the excitation wavelength and emission wavelength of the molecule produce so that background signal interference is effectively reduced. The compound provided by the invention is used for fluorescence imaging of lysosome. In the cell environment, red fluorescence can be emitted under acidic conditions, and the maximum emission wavelength is about 625nm so that the lysosome targeting marker is obtained and background interference is small. The preparation method is sensitive, simple and quick.

A method for detecting the effect of air cleaning apparatus in removing virus features that a test platform with multi-cleaning and-disinfecting system for centralized air conditioner is used, the bacteriophile liquid drips or dust are blown through the air cleaning apparatus to be tested, and the number of bacteriophiles at its entrance and the number of bacteriophiles at its exit are measured to reflect its effect. Its advantages are high sensitivity, and high efficiency.

The utility model discloses a method for detecting blood homocysteine and a kit in the field of biological detection technologies. The kit comprises a kit body, a 96-pore plate, HCY standard substance, HCY specific convertase, a reducing agent, a buffer solution, color developing liquid A and color developing liquid B, wherein the 96-pore plate, the HCY standard substance, the HCY specific convertase, the reducing agent, the buffer solution, the color developing liquid A and the color developing liquid B are arranged in the kit body. The kit utilizes HCY in rHCYase decomposed blood to produce H2S, produced H2S is reacted with dimethyl-p-toluidine to produce methyl blue, and the HCY content in the blood is reflected through the methyl blue generating amount. The kit is simple in operation, a reagent is good in stability and high in repeatability, and the method is flexible and suitable for quick clinical HCY detection of laboratories.

The invention relates to an apparatus and a method for rapidly measuring the sulfur dioxide residue level in a Chinese herb, and belongs to the technical field of drug analysis. The method comprises: a, drawing a standard curve and deriving a calculation formula; b, directly detecting the Chinese herb without treatment; and c, calculating the result. The apparatus comprises a purified water bottle, a sodium hydroxide solution bottle, an o-phthalaldehyde solution bottle, an ammonium acetate solution bottle, a sodium sulfite solution bottle, a multi-channel micro-flow-controlled peristaltic pump, a reaction pool, an ultrasound instrument, a micro-flow-controlled peristaltic pump, a serpentine condensation pipe, a filtration membrane, a cuvette, a detector, and a workstation. The method has characteristics of simple equipment, simple operation, accurate detection result, and effective detection of sulfur dioxide in the Chinese herb.

The invention relates to the field of biotechnology, and particularly relates to applications of a single-stranded nucleotide sequence of an INHA gene as animal superovulation molecule marker, and a detection method. The INHA gene of the western Hunan yellow cattle has Reference SNP Cluster Report:rs41257116 locus, and when being hybridized into A / G, the locus expresses the superovulation advantage. The partial segment at the Reference SNP Cluster Report:rs41257116 locus of the INHA gene of the to-be-detected western Hunan yellow cattle is detected by adopting a PCR-SSCP technology to determine the INHA gene of the western Hunan yellow cattle as AA or AG, the western Hunan yellow cattle with the INHA gene being AG type is selected as western Hunan yellow cattle capable of obtaining better superovulation character. According to the method, the superovulation efficiency of the western Hunan yellow cattle can be increased. The method is simple and convenient, fast and sensitive, a special instrument is not required, and the implementation is convenient.

The invention discloses a doxycycline long-acting injection which has the formula as follows: 5g to 20g of doxycycline, 10g to 60g of propylene glycol, 2g to 4g of MgCl2, 0.2g to 0.5g of Na2S2O5, and water used for injection. The preparation method comprises the following steps: 1. the doxycycline is added into the propylene glycol to obtain a solution (1); 2. the doxycycline hydrochloride, the MgCl2 and the Na2S2O5 are taken and dissolved in the water used for injection to obtain a solution (2); 3. the solution (2) is slowly added into the solution (1) and stirred while being added, and ethylene diamine is used for regulating the pH value to be 7.5 to 8.5; and 4. the water used for injection is added till the total volume reaches 100ml, and filtering, encapsulation and flowing steam sterilization at the temperature of 100 DEG C for 30min are carried out to obtain the finished product. The doxycycline long-acting injection has the advantages of less dosage, long half-life period, less adverse reaction, and the like.

The application discloses a video communication method and device. The method comprises the steps of: detecting a network delay, a packet loss rate and a bandwidth of a transmitted video; determininga network parameter value of the transmitted video, wherein the network parameter value is a weighted array of at least two of the network delay, the packet loss rate and the bandwidth; according to the network parameter value, determining a negotiation code rate and / or a negotiation coding format; sending the determined negotiation code rate and / or negotiation coding format to an opposite end ofvideo communication; and receiving video data processed according to the negotiation code rate and / or the negotiation coding format from the opposite end. According to the method and device disclosedby the invention, the code rate and / or the coding format of video transmission can be regulated in real time according to a network condition so as to ensure quality of video communication.

The present invention relates to the field of pharmaceutical technology, particularly to a preparation method for oligomer impurities of dextro-lipoic acid and analysis detection methods for the oligomer impurities of dextro-lipoic acid. The preparation method for the oligomer impurities comprises: taking dextro lipoic acid as a monomer; dissolving the monomer in an organic solution with low concentration; under catalysis of a free-radical initiator, effectively controlling the polymerization degree for condensation; refining and obtaining a high purity dextro lipoic acid oligomer, the HPLC purity degree of which is higher than 98.5%, by a recrystallization system of water, ethanol and methyl isoamyl ketone so as to facilitate use applications of an impurity reference substance. The present invention also provides an analysis method for measuring the oligomer impurities in the lipoic acid bulk drug or preparation. The method adopts a means of high molecular exclusion chromatography, wherein the mobile phase is phosphate buffer and acetonitrile (97: 3), the detection wavelength is 254 nm, the flow velocity is 0.8 mL / min, the temperature of the column is 25 DEG C, and the injection quantity is 20 [mu]L. The establishment of the analysis method has important significance of qualitative, quantitative analysis and control of the polymer impurities in the lipoic acid bulk drug and preparation.

The invention discloses a method for determining nanomolar active phosphate in seawater, and relates to a method for determining active phosphate with the concentration as nanomolar grade in the seawater. The invention provides the method for determining the nanomolar active phosphate in the seawater which is sensitive, accurate and quick, and is easy for field analysis on ships. The seawater with phosphate is added with a standard solution and is mixed with a reagent; water and a pre-washing solution are used to wash an enriching column after extraction and enrichment; then an extracted substance is eluted; a detector is used to detect at a position between 650 and 850nm; a corresponding signal is recorded; a working curve of the concentration of the phosphate and the corresponding signal is worked out; an actual seawater sample is mixed with the reagent, the water and the pre-washing solution are used to wash the enriching column after the extraction and the enrichment; then the extracted substance is eluted; the detector is used to detect at the position between 650 and 850nm; the corresponding signal is recorded; the standard working curve is used to work out the concentration of the phosphate in the seawater; and the determined concentration of the phosphate is the concentration of the active phosphate according to a definition of the active phosphate.