| Description | Low-Density Lipoprotein (LDL) in plasma is the main carrier of endogenous cholesterol. It is degraded and metabolized by binding to the LDL receptor (LDL-R) on cell membranes and serves as the primary vehicle for transporting cholesterol to peripheral tissues. However, when LDL, especially oxidized Low-Density Lipoprotein (LDL) in plasma is the main carrier of endogenous cholesterol. It is degraded and metabolized by binding to the LDL receptor (LDL-R) on cell membranes and serves as the primary vehicle for transporting cholesterol to peripheral tissues. However, when LDL, especially oxidized LDL (OX-LDL), is present in excess, the cholesterol it carries accumulates in the arterial walls, increasing the risk of atherosclerosis. Atherosclerosis is the pathological basis and risk factor for the majority of cardiovascular and cerebrovascular diseases.Detection Principle: In a cholesterol assay system containing cholesterol esterase (CHER) and cholesterol oxidase (CHOD), specific surfactants are added to selectively solubilize LDL-C for the determination of LDL-cholesterol. Other lipoproteins (HDL, VLDL, chylomicrons) do not react due to inhibition by the surfactants and sugar compounds, remaining in the form of lipoproteins in the reaction mixture. Based on this principle, LDL-cholesterol can be measured directly. Subsequently, esterase catalyzes the hydrolysis of cholesterol esters to generate Free Cholesterol (FC). FC is oxidized by cholesterol oxidase to produce 4-cholestenone and hydrogen peroxide. Hydrogen peroxide then reacts with 4-aminoantipyrine and other components to produce a red quinoneimine compound, which has a characteristic absorption peak at 546 nm. The LDL-C content is determined by measuring the absorbance at 546 nm.Component96TStorageReagent 118 mL2-8℃. Store in the dark.Reagent 26 mL2-8℃. Store in the dark.Standard1EA2-8℃. Store in the dark.Standard (Powder, 1 vial) Preparation:1. Before use, centrifuge at 8000 g, 4°C for 2 minutes to collect the powder at the bottom of the tube.2. Add 0.1 mL of distilled water to dissolve. Use within one week. The prepared concentration is as indicated on the label.User-Prepared Instruments and Reagents:Mortar (Homogenizer), balance, ice box (ice maker), benchtop centrifuge, adjustable micropipettes, water bath (oven, incubator, metal bath), 96-well plate, centrifuge tubes, microplate reader, distilled water (deionized water or ultrapure water are acceptable), ethanol.Experimental ProcedureIt is recommended to first perform a preliminary test using 1-3 samples with expected significant differences (e.g., different types or groups) to familiarize yourself with the procedure and to determine or adjust sample concentrations based on the preliminary results, preventing unnecessary waste of samples or reagents.1. Sample Extraction1.1 Tissue SamplesWeigh approximately 0.1 g of tissue sample and place it in a mortar. Add 1 mL of ethanol and homogenize in an ice bath. Centrifuge at 12,000 rpm, 4°C or room temperature for 10 minutes. Collect the supernatant for assay.Note: If increasing the sample amount, maintain a tissue mass (g) to ethanol volume (mL) ratio between 1:5 and 1:10.1.2 Liquid SamplesAssay clear liquid samples directly. If turbid, centrifuge and use the supernatant for assay.1.3 Bacterial/Cell SamplesCollect bacteria or cells into a centrifuge tube, centrifuge, and discard the supernatant. Add 1 mL of ethanol per approximately 5 million bacteria/cells. Disrupt the bacteria or cells by sonication in an ice bath (power 200W, pulse 3s on, 10s off, repeat 30 times). Centrifuge at 12,000 rpm, 4°C for 10 minutes. Collect the supernatant and keep it on ice for assay.*Note: If increasing the sample amount, maintain a bacteria/cell count (10⁴) to ethanol volume (mL) ratio between 500:1 and 1000:1.*2. Assay Steps2.1 Preheat the microplate reader for 30 minutes (or wait for the instrument to complete its self-check). Set the wavelength to 546 nm.2.2 Thaw all reagents to room temperature (25°C). Add reagents sequentially to a 96-well plate as follows:Reagent (µL)Test TubeStandard Tube (once)Blank Tube (once)Sample2.5Standard2.5Distilled Water2.5Reagent 1180180180Mix well and incubate at 37°C for 5 minutes. Read the absorbance at 546 nm for each tube (A1 ).Reagent 2606060Mix well and incubate at 37°C for 10 minutes. Read the absorbance at 546 nm for each tube (A2 ). Calculate ΔA = A2 - A1 for each tube.Note:(1) If the A2 value for the Test Tube is greater than 1, dilute the sample with ethanol. The dilution factor (D) must be substituted into the calculation formula.(2) If ΔA for the Test Tube is lower than ΔA for the Blank Tube, consider increasing the sample volume V1 (e.g., increase the sample volume in the Test Tube and the water volume in the Blank Tube to 5 µL or more, keeping Reagents 1 and 2 volumes unchanged; for the Standard Tube, keep at 2.5 µL and add 2.5 µL distilled water to make up volume) or increasing the sample weight W (e.g., to 0.2 g or more). The changed V1 or W must then be substituted into the calculation formula.3. Calculation of Results3.1 Based on Sample MassDerived Formula:LDL-C (µmol/g weight) = (CStandard × V2 ) × (ΔATest - ΔABlank ) ÷ (ΔAStandard - ΔABlank ) ÷ (W × V1 ÷ V) × DSimplified Formula:LDL-C (µmol/g weight) = CStandard × (ΔATest - ΔABlank ) ÷ (ΔAStandard - ΔABlank ) ÷ W × D3.2 Based on Protein ContentDerived Formula:LDL-C (µmol/mg prot) = (CStandard × V2 ) × (ΔATest - ΔABlank ) ÷ (ΔAStandard - ΔABlank ) ÷ (Cpr × V1 ÷ V) × DSimplified Formula:LDL-C (µmol/mg prot) = CStandard × (ΔATest - ΔABlank ) ÷ (ΔAStandard - ΔABlank ) ÷ Cpr × D3.3 LDL-C Content in LiquidsDerived Formula:LDL-C (mmol/L) = (CStandard × V2 ) × (ΔATest - ΔABlank ) ÷ (ΔAStandard - ΔABlank ) ÷ V1 × DSimplified Formula:LDL-C (mmol/L) = CStandard × (ΔATest - ΔABlank ) ÷ (ΔAStandard - ΔABlank ) × D3.4 Based on Cell CountDerived Formula:LDL-C (nmol/10⁴ cells) = (CStandard × V2 ) × 10³ × (ΔATest - ΔABlank ) ÷ (ΔAStandard - ΔABlank ) ÷ (500 × V1 ÷ V) × DSimplified Formula:LDL-C (nmol/10⁴ cells) = 2 × CStandard × (ΔATest - ΔABlank ) ÷ (ΔAStandard - ΔABlank ) × DParameter Definitions:CStandard : Concentration as indicated on the label (mmol/L or µmol/mL)V1 : Volume of sample added (0.0025 mL)V: Volume of extraction buffer (ethanol) added (1 mL)V2 : Volume of standard added (0.0025 mL)D: Dilution factor (1 if not diluted)500: Number of cells (in units of 10⁴)W: Sample weight (g)Cpr: Protein concentration of the supernatant (mg/mL); Aladdin's BCA Protein Quantification Kit (B665595) or Ready-to-Use BCA Protein Quantification Kit (R1491648) is recommended.Precautions1. It is recommended to first perform a preliminary test using 1-3 samples with expected significant differences (e.g., different types or groups) to familiarize yourself with the procedure. Based on the preliminary results, determine or adjust sample concentrations to prevent unnecessary waste of samples or reagents.2. This product is for research use only. Not for use in clinical diagnosis. For your safety and health, please wear a lab coat and disposable gloves during operation... Read More | Description：Acetylcholinesterases (AChEs) are enzymes that hydrolyze the neurotransmitter acetylcholine (ACh) to acetate and choline. AChE is located at the synaptic cleft and functions to terminate synaptic transmission by catalyzing the breakdown of ACh allowing cholinergic neurons to Description：Acetylcholinesterases (AChEs) are enzymes that hydrolyze the neurotransmitter acetylcholine (ACh) to acetate and choline. AChE is located at the synaptic cleft and functions to terminate synaptic transmission by catalyzing the breakdown of ACh allowing cholinergic neurons to return to a resting state after activation. It is also found in membranes of red blood cells, motor and sensory fibers, muscles, nerves and central and peripheral tissues. Changes in AChE activity may result from exposure to certain insecticides, which act as cholinesterase inhibitors. Inhibitors of AChE are also used to treat certain conditions such as dementia.Acetylcholinesterase activity assay kit has been used to determine the activity of acetylcholinesterase in a rat organophosphate model and in brain tissue homogenates.Principle：Acetylcholinesterase can catalyze the hydrolysis of acetylcholine to choline, and the reaction of choline with disulfide p-nitrobenzoic acid to produce 5-merhydryl-nitrobenzoic acid (TNB). The product has a characteristic absorption peak at 412 nm, and the activity of acetylcholinesterase can be characterized by the change of light absorption valueThe Dilution Calculator EquationConcentration (start)xVolume (start)= Concentration (final)× Volume (final)This equation is commonly abbreviated as: C1V1 = C2V2... Read More | Cell proliferation detection is a basic experimental method to evaluate the health of cells, genotoxicity and the effect of antitumor drugs. The most accurate method to detect cell proliferation is the BrdU method. Edu detection kit is a revolutionary breakthrough of BrdU method. Edu (5-ethynyl-2 '-Cell proliferation detection is a basic experimental method to evaluate the health of cells, genotoxicity and the effect of antitumor drugs. The most accurate method to detect cell proliferation is the BrdU method. Edu detection kit is a revolutionary breakthrough of BrdU method. Edu (5-ethynyl-2 '- deoxyuridine) is a pyrimidine analog that integrates into the DNA duplex during DNA synthesis. Edu detection is based on the "click" reaction. A copper catalyzed azide reacts covalently with alkynes to form covalent bonds. In this kit, edu contains alkynes, Aladdin ® 488 / 555/594/647a azide dyes contain azide compounds. The edu labeling proliferation of click method is rapid and effective, and easy to use. BrdU method requires DNA denaturation (such as acid denaturation, thermal denaturation or digestion with DNase) to expose BrdU, so as to facilitate BrdU antibody binding; The edu method only needs paraformaldehyde fixation and Triton X-100 penetration to make the detection reagent enter the cells, and only a small amount of azide dye is needed to label the integrated edu very effectively. This kit contains all components required for edu method detection, and can be used for proliferation detection of cultured cells in vitro. Component：Product parameters： 590/617 nm Instruction：Experimental materials (self provided). 10 mM PBS, pH 7.2-7.6. 4% paraformaldehyde fixing solution (in PBS)Propensive reagent (0.5% Triton X -100 in PBS). 2 mg/mL glycine solution (in ddH2O). 3% BSA in PBS, pH 7.2-7.6. 1% BSA in PBS, pH 7.2-7.6. ddH2O. 96/24/12/6 well culture plate or dishFluorescence microscopy detection method1. Cell cultureTake logarithmic growth stage cells and inoculate them into a 96 well plate with 4 × 103-1 × 105 cells per well (the number and density of cells can be adjusted according to cell size, growth rate, and specific requirements of experimental treatment), and culture until normal growth stage.2. Drug treatmentPerform various drug treatments according to experimental needs.3. EdU marking(1) Dilute EdU solution (component A) in a certain proportion with complete cell culture medium to an appropriate concentration, then add it to the cells and mix well; Set up a negative control group without EdU treatment.Note: The labeling concentration of EdU needs to be adjusted according to cell type, and it is recommended to explore with an initial concentration of 10 µ M. In the pre experiment, it is recommended to set an EdU concentration gradient, which can be referred to in Tables 2 and 3.(2) Incubate in a cell culture incubator for 2 hours.Note: The optimal incubation time is related to the cell cycle. Most tumor cell lines can use a 2-hour incubation time, as shown in Appendix 2. The concentration of EdU is related to incubation time,Short term incubation (<2 hours) should use high concentrations, such as 10-50 µ M; Long term incubation (>24 hours) should use low concentrations, such as 1-10 µ M; You can also refer to Appendix 3.4. Cell fixation and permeation promotionNote: For experiments that require cell surface antigen labeling, it can be considered to wash the cells twice with a 3% BSA washing solution after completing EdU incubation, before cell fixation and permeation promotion.(1) After incubation, remove the culture medium. Wash cells twice with 1X PBS for 5 minutes each time to remove EdU residues that have not been incorporated into DNA. Cells with weak adhesion can reduce cleaning intensity. Join 50 µ After incubating at room temperature for 20 minutes with 4% paraformaldehyde fixative, remove the fixative.(2) Add 50 to each hole µ L 2 mg/mL glycine solution, incubate at room temperature for 5 minutes, and neutralize the remaining fixed solution.(3) At a rate of 100 per hole µ Wash cells twice with 3% BSA.(4) Remove the washing solution and add 100 µ L 0.5% Triton X -100, incubate at room temperature for 10 minutes.5. EdU detectionNote: Each sample in this reference step uses 100 µ The working fluid of L can be adjusted by users according to their own sample situation.(1) Prepare 1 x Click iT EdU reaction buffer (component C): Dilute component C 10 times with ddH2O.(2) Configure 5 x Click iT EdU buffer additives (component E): add 300 µ Mix L of ddH2O into a 30 mg E component tube (final concentration of 100 mg/mL) until completely dissolved. After use, the remaining storage solution is stored at -20 ℃ and can be stored for one year. Once the solution turns brown, it indicates that the active ingredients have degraded and cannot be reused.Note: Different specifications of component E are dissolved in ddH2O according to this ratio, and prepared into a 5 x storage solution for future use.(3) Prepare 1 x Click iT EdU buffer additive: Dilute 5 x Click iT EdU buffer additive with ddH2O to 1 x, and the solution should be prepared and used immediately.(4) Prepare Click it working solution according to Table 1.Table 1 Click it working fluid Reaction components Taking the sample size of 10 holes as an example 1 x Click it EdU reaction buffer 855 µL CuSO4 (component D) 40 µL YF® 488/555/594/647A Azide(Component B) 5 µL 1 x Click it EdU buffer additive 100 µL Total volume 1 mL (5) Remove penetration enhancer, 100 per well µ Wash twice with 3% BSA washing solution of L.(6) Add 100 to each hole µ L Click iT working solution, evenly covering cells.(7) Incubate at room temperature in dark for 30 minutes.(8) Remove Click-iT working fluid and add 100 µ After washing cells twice with 3% BSA, remove the washing solution and add 100 µ L PBS keeps cells moist. If there are no other special requirements, photography analysis can be carried out.6. DNA re staining (optional)(1) Using 100 µ Wash the cells once with PBS and remove the washing solution.(2) Dilute Hoechst 33342 (component F) 2000 times with PBS.(3) Add 100 to each hole µ Incubate L 1 x Hoechst 33342 solution at room temperature in dark for 15-30 minutes.(4) Remove Hoechst 33342 solution and use 100 µ Wash cells twice with PBS.7. Imaging and analysisIt is recommended to take fluorescence microscopy photos immediately after staining is completed for observation; If conditions permit, please store in a dark and moist environment at 4 ° C for 3 days before taking photos. Flow cytometry detection method1. Cell cultureInoculate 1 × 105~3 × 106 cells per well into a 6-well plate.2. Drug treatmentPerform various drug treatments according to experimental needs.3. EdU labeled cells(1) Dilute EdU solution (component A) in a certain proportion with complete cell culture medium to an appropriate concentration, then add it to the cells and mix well; Set up a negative control group without EdU treatment.Note: The labeling concentration of EdU needs to be adjusted according to cell type, and it is recommended to explore with an initial concentration of 10 µ M. In the pre experiment, it is recommended to set an EdU concentration gradient, which can be referred to in Tables 2 and 3.(2) Incubate in a cell culture incubator for 2 hours. The time of EdU incubation of cells can be directly used as an indicator for measuring cell DNA synthesis, and the choice of time point and incubation time depend on the cell growth rate. Pulse labeled cells incubated with brief EdU can be used to study cell cycle dynamics.Note: The optimal incubation time is related to the cell cycle. Most tumor cell lines can use a 2-hour incubation time, as shown in Appendix 2. The concentration of EdU is related to the incubation time, and high concentrations, such as 10-50, should be used for short-term incubation (<2 hours) µ M; Long term incubation (>24 hours) should use low concentrations, such as 1-10 µ M; You can also refer to Appendix 3.4. Cell fixation and permeation promotionNote: For experiments that require cell surface antigen labeling, it can be considered to wash cells twice with 1% BSA after completing EdU incubation, before cell fixation and permeation promotion.(1) After incubation, collect cells, add 1 mL of PBS to each tube to clean the cells, centrifuge at 1000 rpm for 5 minutes, and discard the supernatant to remove EdU residue that has not been added to DNA.(2) Add 1 mL of 4% paraformaldehyde fixative to each tube to resuspend cells.(3) Incubate at room temperature for 20 minutes, centrifuge at 1000 rpm for 5 minutes, and discard the supernatant.(4) Add 1 mL of 2 mg/mL glycine to each tube and incubate for 5 minutes. Neutralize the remaining fixed solution, centrifuge at 1000 rpm for 5 minutes, and discard the supernatant. Add 1 mL of PBS to each tube for cleaning once, centrifuge at 1000 rpm for 5 minutes, and discard the supernatant.(5) Add 1mL of 0.5% Triton X-100 osmotic enhancer to each tube and resuspend cells. Incubate at room temperature for 10 minutes.5. EdU detectionNote: For 6-well plate samples, reference can be made to 1 mL of working solution per well. Users can adjust the dosage according to their own sample situation.(1) Prepare 1 x Click iT EdU reaction buffer: Dilute component C 10 times with ddH2O.(2) Prepare 5 x Click iT EdU buffer additives (component E): Add 300 µ L ddH2O to 30 mg of component E in a test tube (final concentration 100 mg/mL), mix well until completely dissolved. After use, the remaining storage solution is stored at -20 ℃ and can be stored for one year. Once the solution turns brown, it indicates that the active ingredients have degraded and cannot be reused.Note: Different specifications of component E are dissolved in ddH2O according to this ratio to form 5 x storage solution for future use.(3) Prepare 1 x Click iT EdU buffer additive: Dilute 5 x Click iT EdU buffer additive storage solution with ddH2O to 1 x, and the solution should be prepared and used immediately.(4) Prepare Click it working solution according to Table 2.Table 2 Click it working fluid Reaction components Volume of liquid required for a single reaction 1×Click-iT EdU reaction buffer 875 µL CuSO4 (component D) 20 µL YF® 488/555/594/647A Azide(Component B) 5 µL 1×Click-iT EdU buffer additive 100 µL Total volume 1 mL (5) Soak at 1000 rpm for 5 minutes, discard the supernatant, remove the enhancer, add 1mL of 1% BSA washing solution to each tube and wash twice. Soak at 1000 rpm for 5 minutes, discard the supernatant.(6) Add 1 mL of Click iT working solution to each tube and mix well.(7) Incubate at room temperature in dark for 30 minutes.(8) Soak at 1000 rpm for 5 minutes, discard the staining reaction solution, add 1% BSA to each tube to wash the cells twice, centrifuge at 1000 rpm for 5 minutes, discard the supernatant, and resuspend the cells again with 1 mL of 1% BSA (the volume of resuspend cells can be adjusted according to the number of cells), and detect with a flow cytometer.Note: If other biomarker tests are required, please refer to step 4.6. Intracellular antigen labeling (optional steps)(1) Add antibody working solution and mix well.(2) Under dark conditions, incubate antibodies at appropriate temperature and time.7. Flow detection and analysis:(1) It is recommended to conduct flow cytometry testing immediately after dyeing is completed; If conditions are limited, please store in a dark place at 4 ℃ for testing, but it should not exceed 3 days.(2) It is recommended to test the number of cells up to one million levels as much as possible. If the number of cells is small, the number of cells tested can be adjusted to 100000 levels starting from the experiment. For cases where the cell yield is too low (just to the level of ten thousand), it may not be conducive to making a flow chart. Therefore, the cleaning frequency in step 5 (8) can be appropriately reduced.Matters needing attention：1. please centrifuge the product to the bottom of the tube immediately before use, and then conduct subsequent experiments. 2. fluorescent dyes have quenching problems. Please try to avoid light during experimental operation to slow down fluorescence quenching. 3. click it edu buffer additive solution should be prepared and used immediately to ensure the best results. 4. for your safety and health, please wear experimental clothes and disposable gloves.Scope of application：Cell proliferation detection (cell imaging flow universal)... Read More | Inquire | Product introduction：This kit uses an improved SDS alkaline lysis method combined with DNA preparation membrane to selectively adsorb DNA to achieve the purpose of rapid purification of plasmid DNA. It is suitable for extracting up to 500ug of high-purity plasmid DNA from 120-300ml bacterial Product introduction：This kit uses an improved SDS alkaline lysis method combined with DNA preparation membrane to selectively adsorb DNA to achieve the purpose of rapid purification of plasmid DNA. It is suitable for extracting up to 500ug of high-purity plasmid DNA from 120-300ml bacterial culture for sequencing, in vitro transcription and translation, restriction enzyme digestion, bacterial transformation and other molecular biology experiments.Scope of application：Nucleic acid extraction and purification... Read More |