| 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 | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | Inquire | RAFT Agent Kit for controlling polymerizations at the molecular level detailed list of products: Catalog Number Product Name Component Catalog Number Component Name Component CAS Specification&Purity R396714 RAFT Agent Kit for controlling polymerizations at the molecular level C139356-500mg 4-RAFT Agent Kit for controlling polymerizations at the molecular level detailed list of products: Catalog Number Product Name Component Catalog Number Component Name Component CAS Specification&Purity R396714 RAFT Agent Kit for controlling polymerizations at the molecular level C139356-500mg 4-Cyano-4-(dodecylsulfanylthiocarbonyl)sulfanylpentanoic acid 870196-80-8 See Component Catalog Number R396714 RAFT Agent Kit for controlling polymerizations at the molecular level C396701-500mg Cyanomethyl dodecyl trithiocarbonate 796045-97-1 See Component Catalog Number R396714 RAFT Agent Kit for controlling polymerizations at the molecular level C396703-500mg Cyanomethyl methyl(phenyl)carbamodithioate 76926-16-4 See Component Catalog Number R396714 RAFT Agent Kit for controlling polymerizations at the molecular level C168358-500mg 2-Cyano-2-propyl benzodithioate 201611-85-0 See Component Catalog Number R396714 RAFT Agent Kit for controlling polymerizations at the molecular level C396706-500mg 2-(2-Cyanoprop-2-yl)-S-dodecyltrithiocarbonate 870196-83-1 See Component Catalog Number R396714 RAFT Agent Kit for controlling polymerizations at the molecular level C132316-500mg 4-Cyano-4-(phenylcarbonothioylthio)pentanoic Acid 201611-92-9 See Component Catalog Number R396714 RAFT Agent Kit for controlling polymerizations at the molecular level S396708-500mg S,S-Dibenzyl trithiocarbonate 26504-29-0 See Component Catalog Number R396714 RAFT Agent Kit for controlling polymerizations at the molecular level D396711-500mg 2-(Dodecylthiocarbonothioylthio)-2-methylpropionic acid 461642-78-4 See Component Catalog Number... Read More | This product is a cDNA first strand synthesis kit specially prepared for the first step experiment of two-step RT-PCR. The reverse transcriptase used in this kit is a novel and efficient reverse transcriptase that utilizes E. coli engineered bacteria for recombination and expression. It removes This product is a cDNA first strand synthesis kit specially prepared for the first step experiment of two-step RT-PCR. The reverse transcriptase used in this kit is a novel and efficient reverse transcriptase that utilizes E. coli engineered bacteria for recombination and expression. It removes RNase H activity and enhances its thermal stability. It can synthesize cDNA first strands using extremely low amounts of total RNA or mRNA, with an initial sample size as low as pg level. SuperRT reverse transcriptase has strong affinity for RNA and can read RNA templates with high GC content and complex secondary structures, obtaining high yields of cDNA. This product contains all the reagents required for reverse transcription from RNA templates to cDNA first strand, including Super RT efficient reverse transcriptase, reaction buffer, primers, dNTP, etc. It is simple and convenient to use. This system has high compatibility with subsequent PCR and quantitative PCR experiments, and is suitable for various DNA polymerase reactions. S665657 Component 100 T Storage S665657A SuperRT, 200 U/µL 100 µL -20℃. Avoid freeze/thaw cycle. S665657B 5×SuperRT Buffer 500 µL -20℃. Avoid freeze/thaw cycle. S665657C Primer Mix 240 µL -20℃. Avoid freeze/thaw cycle. S665657D dNTP Mix, 2.5 mM Each 500 µL -20℃. Avoid freeze/thaw cycle. S665657E RNase-Free Water 1 mL -20℃. Avoid freeze/thaw cycle.Product features:·Efficient reverse transcription: It has a high affinity for RNA templates, with a reverse transcription efficiency of up to 90%, and can recognize pg level templates.·Free response to complex templates: Even templates with high GC content and complex secondary structures can achieve good results without high-temperature denaturation.Notes:1. During the operation process, RNase contamination should be avoided to prevent RNA degradation or cross contamination during experiments. It is recommended to perform RNA operations in specialized areas, use specialized instruments and consumables, and have operators wear masks and disposable gloves, and frequently change gloves.2. Disposable plastic containers should be used as much as possible for experiments. If glass containers are used, they should be treated with a 0.1% DEPC (diethyl pyrocarbonate) aqueous solution at 37 ℃ for 12 hours, and sterilized under high pressure at 120 ℃ for 30 minutes before use. Alternatively, glass containers should be sterilized under dry heat at 180 ℃ for 60 minutes before use. The sterile water used in the experiment should be treated with 0.1% DEPC and then subjected to high-pressure sterilization.3. All reagents in this reagent kit should be gently mixed upside down before use, avoiding foaming as much as possible, and used after brief centrifugation. The enzymes involved should be returned to -20 ℃ as soon as possible after use to avoid repeated freeze-thaw cycles.If the initial amount of RNA is less than 50 ng, it is recommended to add RNA enzyme inhibitors (RNAsin). This kit is not provided.Usage:Note: 1 ng -5 µ g of total RNA can establish a 20 µ l reaction system. If the total RNA amount is greater than 5 µ g, please expand the reaction system proportionally.Steps for reverse transcription:1. Dissolve the RNA template, Primer Mix, dNTP Mix, SuperRT Buffer, SuperRT, and RNase Free Water and place them on ice for later use.2. Prepare a reaction system according to the following table, with a total volume of 20 µ L. Reagent 20 µlReaction system Final concentration dNTP Mix，2.5 mM Each 4 µl 500 µM Each Primer Mix 2 µl / RNA Template X µl 50 pg-5 µg SuperRT，200 U/µl 1 µl / RNase-Free Water up to 20 µl / Attention:1) If the initial amount of RNA is less than 50 ng, it is recommended to add RNA enzyme inhibitors (RNAsin). This kit is not provided.2) Primer Mix is formulated from Oligo (dT) and Random Primer. Oligo dT Primer or Gene Specific Primer can be used according to experimental needs, with a recommendation of 20 µ The reaction system Oligo dT Primer is 50 pmol, or Gene Specific Primer is 2 pmol.3. Vortex shake and mix well, briefly centrifuge to collect the solution on the pipe wall to the bottom of the pipe.Incubate at 4.42 ℃ for 30-50 minutes and 85 ℃ for 5 minutes. After the reaction is complete, centrifuge briefly and cool on ice.5. Reverse transcripts can be directly used for PCR reactions and fluorescence quantitative PCR reactions, or stored at -20 ℃ for a long time. Reagent 20 µ Final concentration of reaction system dNTP Mix, 2.5 mM Each 4 µ L 500 µ M Each Primer Mix 2 µ RNA Template X µ L 50 pg-5 µ g 5 x SuperRT Buffer 4 µ 1 x SuperRT, 200 U/ µ L 1 µ RNase Free Water up to 20 µ Lii If the reverse transcription efficiency is low, or the RNA template secondary structure is complex and the GC content is high, the following steps are recommended:1. Dissolve the RNA template, Primer Mix, dNTP Mix, SuperRT Buffer, SuperRT, and RNase Free Water and place them on ice for later use.2. Configure the reaction system according to the following table, with a total volume of 15 µ L. Reagent 20 µlReaction system Final concentration dNTP Mix，2.5 mM Each 4 µl 500 µM Each Primer Mix 2 µl / RNA Template X µl 50 pg-5 µg RNase-Free Water up to 15 µl / Note: Primer Mix is formulated from Oligo (dT) and Random Primer. Oligo dT Primer or Gene Specific Primer can be used according to experimental needs. 3. Incubate at 70 ℃ for 10 minutes and quickly ice bath for 2 minutes.4. Centrifuge briefly to collect the solution on the tube wall to the bottom of the tube.5. Continue to add the following reagents to the above reaction solution: Reagent 20 µlReaction system Final concentration 5×SuperRT Buffer 4 µl 1× SuperRT，200 U/µl 1 µl / Note: If the initial amount of RNA is less than 50 ng, it is recommended to add RNA enzyme inhibitors (RNasins). This kit is not provided. 6. Incubate at 42 ℃ for 30-50 minutes and 85 ℃ for 5 minutes.7. After the reaction is complete, centrifuge briefly and cool on ice.8. Reverse transcripts can be directly used for PCR reactions and fluorescence quantitative PCR reactions, or stored at -20 ℃ for a long time... Read More |