| Description | Free Fatty Acids (FFA), also known as Non-Esterified Fatty Acids (NEFA), are primarily produced by the hydrolysis of neutral fats. They are intermediate products in fat metabolism, involved in cell proliferation, inflammatory responses, and hormone regulation. FFA can also act as signaling moleculesFree Fatty Acids (FFA), also known as Non-Esterified Fatty Acids (NEFA), are primarily produced by the hydrolysis of neutral fats. They are intermediate products in fat metabolism, involved in cell proliferation, inflammatory responses, and hormone regulation. FFA can also act as signaling molecules with various physiological functions. Free fatty acids are closely related to lipid metabolism, glucose metabolism, and endocrine function. Their concentration is an important physiological and biochemical indicator, serving as an auxiliary parameter for disease evaluation and diagnosis, and also reflecting quality changes during food storage.Detection Principle: FFAs combine with copper ions to form copper soaps, which are soluble in chloroform. The copper ions can then react with a chromogenic solution to form a purplish-red complex. This product has a characteristic absorption peak at 550 nm. The FFA content can be quantified by measuring the change in absorbance.Detection Range: 0.0313 - 2 mMSensitivity: 0.0156 mMApplicable Samples: Serum (plasma), animal/plant tissues, cells, bacteria.A1492746Component48T96TStorageA1492746ACu Reagent6 mL12 mL2-8℃. Store in the dark.A1492746BChromogen15 mL30 mL2-8℃. Store in the dark.A1492746CStandard (16.41 mg Palmitic Acid)1 EA1 EA2-8℃. Store in the dark.User-Prepared Instruments and ReagentsMicroplate reader or visible spectrophotometer (capable of measuring absorbance at 550 nm)Incubator, Ice maker, Low-temperature centrifuge96-well plate or micro glass cuvettes, Adjustable pipettes and tipsHomogenizer (for tissue samples)Glass bottle (for preparing extraction buffer)n-Heptane, Anhydrous methanol, ChloroformExperimental Procedure1. Reagent PreparationReagent NameReagent PreparationPrecautionsExtraction Buffer (Self-prepared)In a glass bottle, mix Chloroform : n-Heptane : Anhydrous Methanol = 28 : 21 : 1. Cap tightly and mix well.Store at 4°C protected from light.Cu ReagentReady-to-use; equilibrate to room temperature before use; mix well before use.Store at 4°C protected from light.ChromogenReady-to-use; equilibrate to room temperature before use.Store at 4°C protected from light.StandardBefore use, dissolve contents in 1 mL of Extraction Buffer to obtain a 64 mM Standard solution. Mix well.Unused dissolved Standard can be stored in a tightly sealed glass bottle at 4°C protected from light for 1 month.2. Standard Curve SetupDilute the 64 mM Standard further with Extraction Buffer as shown in the table below.Standard No.Standard (µL)Extraction Buffer Volume (µL)Standard Concentration (mM)Std.120µL of 64mM stock6202Std.2100µL of Std.11001Std.3100µL of Std.21000.5Std.4100µL of Std.31000.25Std.5100µL of Std.41000.125Std.6100µL of Std.51000.0625Std.7100µL of Std.61000.0313Note: Prepare freshly diluted standards for each experiment.3. Sample PreparationNote: Fresh samples are recommended. If not used immediately, samples can be stored at -80°C for up to 6 months.3.1 Animal Tissues: Weigh approximately 0.1 g of tissue, add 1 mL of Extraction Buffer, and homogenize on ice. Centrifuge at 8,000 rpm, 4°C for 10 min. Collect the supernatant and keep on ice for detection.3.2 Plant Tissues: Weigh approximately 0.1 g of tissue, add 1 mL of Extraction Buffer, and grind. Disrupt by ultrasonic homogenization on ice (power 20% or 200 W, ultrasonicate for 3 s, interval 7 s, repeat 30 times). Centrifuge at 8,000 rpm, 4°C for 10 min. Collect the supernatant and keep on ice for detection.3.3 Cells or Bacteria: Collect 5 million cells or bacteria into a centrifuge tube. Wash with cold PBS, centrifuge, and discard the supernatant. Add 1 mL of Extraction Buffer. Disrupt by ultrasonic homogenization on ice (power 20% or 200 W, ultrasonicate for 3 s, interval 7 s, repeat 30 times). Centrifuge at 8,000 rpm, 4°C for 10 min. Collect the supernatant and keep on ice for detection.3.4 Serum (Plasma) and other liquids: Detect directly.4. Assay Steps4.1 Instrument Preparation: Preheat the microplate reader or visible spectrophotometer for at least 30 minutes. Set the wavelength to 550 nm. For spectrophotometers, zero the instrument with deionized water.4.2 Sample Assay (Add reagents sequentially to EP tubes):ReagentBlank Tube (µL)Standard Tube (µL)Test Tube (µL)Extraction Buffer240200200Various Std.0400Sample0040Cap the tubes tightly and vortex at medium speed for 30 seconds.Cu Reagent808080Cap the tubes tightly and vortex at medium speed for 30 seconds. Incubate at room temperature (25°C) for 20 minutes. Centrifuge at 2,000 g, room temperature (25°C) for 5 minutes.Upper Phase505050Chromogen2002002004.3 Incubate at room temperature (25°C) for 5 minutes. Transfer 200 µL from each tube to the corresponding wells of a 96-well plate or micro glass cuvettes. Measure the absorbance at 550 nm.Calculate ΔAtest=Atest-Ablank and ΔAstd=Astd-Ablank (The blank tube only needs to be set up once).Note: The measurement must be completed within 30 minutes after color development. It is recommended to perform preliminary experiments with 2-3 samples expected to have significant differences before formal testing. If Atest exceeds the detection range of the instrument, dilute the sample further with Extraction Buffer and multiply the result by the dilution factor.5. Result CalculationWe provide both derived and simplified calculation formulas, which are equivalent. The simplified formulas in bold are recommended as the final calculation formulas.5.1 Standard Curve PlottingPlot the standard curve with standard concentration as the y-axis and ΔAstd as the x-axis (using concentration as the y-axis facilitates calculation). Substitute ΔAtest into the standard curve equation to obtain y (mM).5.2 Sample FFA Content Calculation(1) Based on sample mass:FFA Content (µmol/g fresh weight) = y × Vextract ÷ W × n = y ÷ W × n(2) Based on bacterial or cell count:FFA Content (µmol/10⁴ cells) = y ÷ (Cell or Bacterial Count ÷ Vextract ) × n = y ÷ 500 × n = 0.002 × y × n(3) Based on liquid volume:FFA Content (µmol/L) = 1000 × y × nParameter Description:Vextract : Volume of Extraction Buffer added, 1 mLW: Sample mass, gn: Sample dilution factor (if further diluted)500: Cell or bacterial count, in units of 10⁴1000: Unit conversion factor, 1 L = 1000 mL6. Result PresentationTypical Standard Curve: y = 0.679x - 0.0109, R² = 0.9988(Free Fatty Acid (FFA) standard curve analyzed using a 96-well plate. Data and curve are for reference only; users must establish their own standard curve based on their experiment.)Precautions1. Biochemical reagents are generally irritating and biologically toxic. For your safety and health, please implement appropriate biosafety precautions throughout the experiment. Wear personal protective equipment such as lab coats, masks, gloves, and hair caps. Perform experiments in a fume hood or biosafety cabinet.2. This product is for scientific research use only. Not intended for clinical diagnosis... 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 | Product introduction：PMA qPCR live bacteria detection kit provides an effective means to detect bacterial activity. This kit provides a mixture of PMA dye and SYBR green dye based qPCR. The optimal amount of dye and the number of samples that can be processed may vary depending on the type ofProduct introduction：PMA qPCR live bacteria detection kit provides an effective means to detect bacterial activity. This kit provides a mixture of PMA dye and SYBR green dye based qPCR. The optimal amount of dye and the number of samples that can be processed may vary depending on the type of sample. PMA is a DNA binding dye with high affinity, especially with double stranded DNA. The dye itself has weak fluorescence, but it can emit brighter fluorescence after binding with nucleic acids. PMA is impermeable to the cell membrane, so it can selectively modify the DNA of dead cells with damaged membrane. After bllight (~464 nm) photolysis of PMA modified DNA, the photoreactive azido group on PMA is converted into highly reactive azene radical, which reacts with any hydrocarbon moiety near the DNA binding site to form a stable covalent nitrogen carbon bond, resulting in permanent DNA modification. This modification process will make the DNA insoluble, and it will be lost together with cell debris in the later genomic DNA extraction process. The unbound PMA remaining in the solution reacts with water molecules under strong light irradiation and decomposes into hydroxylamine compounds without cross-linking activity, so that it can no longer covalently bind DNA. Based on this characteristic of PMA, our company combines PMA and qPCR technology to form a new detection method - PMA qPCR, which is used for the screening of live bacteria. At present, the method has been validated in a variety of bacterial strains as well as yeast, fungi, viruses and parasites. The treatment of complex samples, such as feces or soil, may require optimization of sample dilution, dye concentration, and light treatment time. Treatment of diluted samples, such as water testing, may require filtration or concentration prior to dye treatment. Component： Instruction： Precautions before use：1.This live bacteria detection kit distinguishes dead bacteria and live bacteria according to cell membrane permeability. Many methods of killing bacteria cause damage to the cell membrane and are therefore compatible with this kit. But some methods, such as ultraviolet irradiation, may not immediately cause cell membrane rupture. Therefore, before selecting this kit, it is necessary to carry out literature search and pre-experiment to determine whether the kit is suitable for the bacterial type and killing method you choose. 2.After PMA treatment, the bacteria need to be photolyzed to covalently bind the dye to dead cell DNA. Photolysis operations can use blue or white light sources. Generally speaking, the brighter the lamp, the higher the efficiency of the photolysis step. Non-LED lamps ( such as halogen lamps ) may heat your sample and have a negative impact on the analysis. Ice is required to cool the sample during irradiation. 3.Sample can be cryopreservation after photolysis. Frozen samples before PMA treatment photolysis may damage the cell membrane and produce false negative results. If the sample needs to be frozen before detection, it is recommended to perform a pre-experiment first. 4.Part of the mechanism of PMA is to remove PMA covalently modified DNA from the sample by precipitation ; therefore, when extracting genomic DNA, it is necessary to use the same volume of genomic DNA eluent for volume normalization. The positive control can use the genomic DNA of living cells. 5.In order to verify the effectiveness of PMA in the test sample, the Ct ( dCt ) changes between- / + PMA can be compared. Experimental materials ( self-provided )：①Light source ( used for the photolysis step after PMA modified DNA ) ;② Bacterial genomic DNA extraction kit ; Experimental procedure： 1.Suck 10 µL of E.coli bacterial solution in liquid LB medium, and culture E.coli in the bacterial incubator overnight or longer to the logarithmic growth phase ( OD600 ≈ 1.0 ) ; Note : The culture time is adjusted according to the experiment. 2.Two portions of live E.coli, 400 µL each, were placed in a clean centrifuge tube ; 3. ( Recommended ) Preparation of dead E.coli. If the dead E.coli is needed as a control, the dead E.coli can be obtained by heating the living E.coli in a water bath at 95 °C for 5 min, or at 58 °C for 3 h. the subsequent operation of the dead E. coli is the same as that of the living E. coli ; 4.Two copies of live E.coli, one without PMA treatment, and one with 25 µM PMA treatment ( the optimal PMA concentration for treating different types or different sources of bacteria needs to be consulted in the relevant literature ) ; 5.The PMA-treated samples were placed on a shaker at room temperature and incubated in the dark for 10 min to fully mix the dye with the sample ; 6.Exposure of the sample, you can use blue or white light source, irradiation time to explore their own. For example, a 60 W blue light can be used for 15 min. Note : 1 If a halogen lamp is used, we recommend that the PMA-treated sample tube be placed on an ice block 20 cm away from the light source. Ice should be placed in a transparent tray. Adjust the light source to point directly to the sample, photolysis for 5-15 min ; if the bacteria obtained from the environment are directly used for experiments, due to the complexity or turbidity of the environmental samples, the photolysis time needs to be prolonged appropriately. 7.Treated and untreated live E.coli 5000 × g, centrifuged for 10 min, remove the supernatant ; 8.Select the appropriate genomic DNA extraction kit according to the sample type, and use the same elution volume for each group of samples when elution DNA. Note : DNA extraction steps refer to the instructions of the kit used. Part of the mechanism of action of PMA is to remove PMA-bound DNA from the sample by precipitation ; therefore, when extracting genomic DNA, each group should use the same volume of genomic DNA eluent for volume normalization ( the amount of genomic DNA extracted from dead bacteria and live bacteria is inconsistent, so the concentration of the two is significantly different ). 9.Preparation of reaction mixture according to the following system : Note : 1 For the DNA extracted by commercial DNA extraction kit, the qPCR template was optimized with 2 µL as the initial volume ; 2 The template volume should not exceed 10 % of the final reaction volume ; 3 Template concentration : gDNA as template, usually 1-10 ng ; the final concentration of PCR primers is usually 0.4µM, which can get better results. When the reaction performance is poor, the primer concentration can be adjusted in the range of 0.2-1µM. 10.Slightly vortex the reaction mixture, transfer the fixed volume to the PCR tube. 11. Test procedureNote : 1 The extension time is adjusted according to the instrument ; the Taq enzyme in mix can be activated within 2 min, but the genomic DNA may require longer denaturation time, which can be increased at this time, and the specific denaturation time can be adjusted according to the sample type. 12. ( Optional ) Data analysis Using live bacteria and dead bacteria as controls, the number of live cells in the sample was analyzed and calculated. It is recommended to verify the suitability of primers and PCR procedures before starting PMA qPCR detection of live bacteria. Calculation of dead and living bacteria control dCt ( 1 ) After the end of qPCR, the Ct value of each sample was calculated by instrument software ; ( 2 ) By calculating the dCt of each control bacteria, it was judged whether PMA successfully inhibited the amplification of dead bacterial DNA. The calculation is as follows : dCt live = Ct ( live, PMA treated ) -Ct ( live, PMA untreated ) dCt die = Ct ( die, PMA treated ) -Ct ( die, PMA untreated ) ( 3 ) The dCt expectation of living bacteria is close to 0 ± 1, which indicates that PMA does not affect the amplification of living cell DNA ; ( 4 ) The expected value of dCt of dead bacteria is greater than 4 ( dCt is 4 means that it is reduced by about 16 times, that is, 94 % of dead bacterial DNA is removed ; a dCt of 8 indicated a decrease of about 250 times, that is, 99.6 % of the dead bacterial DNA was removed ).( 5 ) The dCt of dead bacteria depends on many factors, including : strain / cell type ; the way bacteria are killed ; the concentration of PMA used ; amplified sequence length. 3. Calculation of the proportion of viable ( optional ) bacteria If the control results of dead and live bacteria are normal, the proportion of live bacteria in the sample can be calculated.( 1 ) Calculate the dCt value of the sample : dCt sample = Ct ( sample, PMA treated ) -Ct ( sample, PMA untreated ) ( 2 ) Conversion of dCt value to live bacteria ratio : PMA inhibition multiple = 2 ( sample dCt ) Viable bacteria % = 100 / PMA inhibition multiple 14. ( Optional ) Calculate the absolute number of live bacteria If you want to calculate the absolute number of viable bacteria in the sample, you need to use a known number of target bacteria genomic DNA to make a standard curve. It is recommended that the diluted concentrations of several groups of genomes are within the range of the qPCR analysis system. ( 1 ) qPCR was performed with the appropriate genome, and the Ct value was used as the ordinate, and the number of cells was used as the abscissa. The R2 value is calculated to determine the linearity, and the slope and y-axis intercept are displayed.( 2 ) Calculate the copy number of the experimental samples : Ct = slope * cell number + y axis intercept ( y = mx + b ) Bacterial count sample = ( Ct-y axis intercept ) / slope Note : The live bacterial DNA was not lost during the purification process. Examples : Product parameters：Pma: ex = 464 nm; Ex/em = 510/610 nm (following photolysis and reaction with dna/rna)Scope of application：Live bacteria detection Matters needing attention：1.Please instantaneously centrifuge the product to the bottom of the tube before use, and then carry out subsequent experiments ; 2.the kit components contain fluorescent dyes, and attention should be paid to avoiding light during use and preservation ; 3.For your safety and health, please wear experimental clothes and disposable gloves... Read More | Product content R669871Component50 TStorageR669871ADNase I1000 U-20℃. Avoid freeze/thaw cycle.R669871B10×Reaction Buffer1mL-20℃. Avoid freeze/thaw cycle. R669871CBuffer DS30 mLRTR669871DBuffer GTL15 mLRTR669871EBuffer GL25 mLRTR669871FProteinase K12.5 mgRTR669871GProteinase K Product content R669871Component50 TStorageR669871ADNase I1000 U-20℃. Avoid freeze/thaw cycle.R669871B10×Reaction Buffer1mL-20℃. Avoid freeze/thaw cycle. R669871CBuffer DS30 mLRTR669871DBuffer GTL15 mLRTR669871EBuffer GL25 mLRTR669871FProteinase K12.5 mgRTR669871GProteinase K Storage Buffer1.25 mLRTR669871HBuffer RW140 mLRTR669871IBuffer RW2 (concentrate)11 mLRTR669871JRNase-Free Water10 mLRTR669871KSpin Columns RS with Collection Tubes50 setsRTR669871LRNase-Free Centrifuge Tubes (1.5 mL)50 EART Product IntroductionThis kit is suitable for effectively purifying total RNA from formalin fixed and paraffin embedded tissues. Suitable for extracting total RNA with improved purity from paraffin embedded tissues or sections less than 30mg. This kit does not require the use of phenol/chloroform extraction or isopropanol precipitation, and can complete the extraction of multiple samples within one hour. This product uses specially optimized lysis solution and protease K to release RNA from formalin fixed or tissue slice samples without overnight operation; After digestion, the sample is incubated at a higher temperature to remove the inhibitory effect caused by formalin cross-linking, effectively releasing RNA from tissue slices and avoiding endangering RNA integrity; The optimized buffer system allows RNA in the lysis solution to specifically bind to the silica gel adsorption membrane, while other pollutants can flow through the membrane; It can be effectively removed through rinsing steps, and the washed RNA can be directly used for experiments such as RT-PCR, Real Time PCR, and Western blot analysis.Self prepared reagents: anhydrous ethanol (newly opened or dedicated for RNA extraction), 10mM PBS (pH 7.4).Preparation and important precautions before the experiment1. Add 0.625ml Protein K Storage Buffer to Protein K to dissolve it and store at -20 ℃. The prepared Protein K should not be left at room temperature for a long time to avoid repeated freeze-thaw cycles, which may affect its activity.2. To prevent RNase pollution, attention should be paid to the following aspects:1) Use RNase free plastic products and gun heads to avoid cross contamination.2) Glassware should be dry baked at a high temperature of 180 ℃ for 4 hours before use, while plastic containers can be soaked in 0.5M NaOH for 10 minutes, thoroughly rinsed with water, and then sterilized under high pressure.3) Prepare the solution using water without RNase.4) Operators should wear disposable masks and gloves, and change gloves frequently during the experiment.3. After obtaining the sample, it should be fixed in 4% -10% formalin as soon as possible, with a suitable fixation time of 14-24 hours. Excessive time can lead to RNA breakage and affect downstream experiments.4. Ensure that the sample before embedding is thoroughly dehydrated, as residual formalin will inhibit the action of Protein K.5. Before the first use, anhydrous ethanol should be added to Buffer RW2 according to the instructions on the reagent bottle label.Before use, please check if there is any crystallization or precipitation in Buffer GTL, Buffer GL, and Buffer DS. If there is any crystallization or precipitation, please dissolve Buffer GTL, Buffer GL, and Buffer DS again in a 56 ℃ water bath.Operation steps1. Sample processing1a. Paraffin embedded sample: Use a surgical knife to trim off excess paraffin from the tissue block, expose the tissue, and cut into 5-10 µ m thin slices.Attention: If the surface of the sample has already been exposed to air, please discard 2-3 pieces that come into contact with the air and do not use them.1b. Samples in fixed solutions such as formalin: Take approximately 20mg of the sample, cut it into small pieces, place it in a centrifuge tube, and add 500 µ 10mM PBS (PH7.4), vortex oscillation, centrifugation at 12000 rpm (~13400 × g) for 1 minute, discard the supernatant, repeat 3 times, and proceed directly to step 3.2. Choose option A or option B to remove paraffinOption AA1. Take approximately 1 × 1cm2 of slices (4-5 slices in total) and place them in a centrifuge tube (prepared by oneself), then add 500 slices µ L Buffer DS, vortex oscillation for 10 seconds. Incubate at 56 ° C for 3 minutes.Centrifuge at A2.12000 rpm for 2 minutes, be careful to discard the supernatant and avoid attracting sediment.Option BB1. Take approximately 4-5 slices of approximately 1 × 1 cm2 and place them in a centrifuge tube (self prepared). Add 1ml of xylene, cover the tube tightly, and vortex for 10 seconds.B2.Centrifuge at 12000 rpm for 2 minutes, be careful to remove the supernatant and avoid removing sediment.B3. Add 1ml of anhydrous ethanol, vortex and shake well. Centrifuge at 12000 rpm for 2 minutes, discard the supernatant, and be careful not to absorb or discard the sediment.B4. Open the tube cover and incubate at room temperature or up to 37 ° C for 10 minutes until there is no ethanol residue.3. Add 150µ L Buffer GTL, resuspended precipitation; Join 10µl Protein K, vortex oscillation mixing.4.Incubate at 56 ℃ for 15 minutes until the sample is completely dissolved. Incubate at 80 ℃ for 15 minutes. Short centrifugation allows the solution on the tube wall to be collected to the bottom of the tube.Note: 1) The purpose of this step is to repair nucleic acids denatured by formaldehyde. Incubating at a high temperature or for too long may cause RNA breakage, resulting in RNA fragments.2) The sample incubated at 56 ℃ can be placed at room temperature until the temperature of the water or dry bath reaches 80 ℃, and then the sample can be incubated at 80 ℃.5. Place on ice for 3 minutes, centrifuge at 12000 rpm for 15 minutes, transfer the supernatant to a new centrifuge tube, be careful not to suck sediment.6. Add 320 to the supernatant µ L Buffer GL, vortex oscillation thoroughly mixed.7. Join 720 µ Mix anhydrous ethanol thoroughly with vortex oscillation.Attention: After adding anhydrous ethanol, there may be a small amount of precipitate precipitation, but it does not affect subsequent operations.8. Add all the solutions obtained in step 7 to the spin columns RS that have been loaded into the collection tube. If the solution cannot be added at once, it can be transferred multiple times. Centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.Optional steps: If genomic DNA needs to be removed, the following steps can be followeda. Add 350 to the adsorption column µ L Buffer RW1, centrifuge at 12000 rpm for 1 minute, discard the waste liquid, and place the adsorption column back into the recovery manifold.b. Preparation of DNase I mixture: Take 52 µ Add 8 RNase Free Water to it µ 10 x Reaction Buffer and 20 µ DNase I (1U/ µ l) Mix well and prepare to a final volume of 80 µ The reaction solution of L.c. Add 80 µ l of DNase I mixture directly to the adsorption column and incubate at 20-30 ℃ for 15 minutes.d. Add 350 to the adsorption column µ L Buffer RW1, centrifuge at 12000 rpm for 1 minute, discard the waste liquid, and place the adsorption column back into the recovery manifold.9. Add 500 to the adsorption column µ Buffer RW2 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.10. Repeat step 9.Centrifuge at 11.12000 rpm for 2 minutes and discard the waste liquid from the collection tube. Place the adsorption column at room temperature for a few minutes to thoroughly air dry.Note: The purpose of this step is to remove residual ethanol from the adsorption column, which will affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).12. Place the adsorption column in a new RNase free centrifuge tube, and add 20-50µl to the middle of the adsorption column in the air Place RNase Free Water at room temperature for 2-5 minutes, centrifuge at 12000 rpm for 1 minute, collect RNA solution, and store RNA at -20 ℃.Note: 1) The volume of RNase Free Water should not be less than 20 µ l. Small volume affects the recovery rate. 2) If you want to increase RNA production, you can use 20-50 µ Repeat step 12 for the new RNase Free Water.3) If you want to increase the RNA concentration, you can add the obtained solution back to the adsorption column and repeat step 12... Read More |