L-谷氨酸[谷氨酸盐/谷氨酸酯/味精/谷氨酸单钠]检测试剂盒 L-Glutamic Acid Assay Kit 货号:K-GLUT Megazyme中文站

L-谷氨酸[谷氨酸盐/谷氨酸酯/味精/谷氨酸单钠]检测试剂盒

英文名:L-Glutamic Acid Assay Kit

货号:K-GLUT

规格:60 assays (manual) /

分析物意义:常见的天然食品组分,例如在奶酪和番茄中或调味剂中,如味精 

Megazyme检测试剂盒优点:提供的硫辛酰胺脱氢酶是稳定的悬浮液而不是可溶性粉末,从而减少了酶的浪费 

The L-Glutamic Acid test kit is a simple, reliable, rapid and accurate method for the measurement and analysis of L-glutamate (MSG) in foodstuffs.
Suitable for manual, auto-analyser and microplate formats.

Colourimetric method for the determination of L-Glutamic Acid
(Monosodium Glutamate; MSG) in foodstuffs and other materials

Principle:
(beef liver glutamate dehydrogenase)
(1) L-Glutamic acid + NAD+ + H2O ↔ 2-oxoglutarate + NADH + NH4+

(diaphorase)
(2) INT + NADH + H+ → NAD+ + INT-formazan

Kit size: 60 assays (manual) / 600 (microplate)
/ 700 (auto-analyser)
Method: Spectrophotometric at 492 nm
Reaction time: ~ 9 min
Detection limit: 0.21 mg/L
Application examples:
Fruit and vegetables (e.g. tomato), processed fruit and vegetables
(e.g. tomato puree / juice, ketchup, soy sauce), condiments, processed
meat products (e.g. extracts, bouillon and sausages), soup, pharmaceuticals
and other materials (e.g. biological cultures, samples, etc.)
Method recognition:
Methods based on this principle have been accepted by ISO, GOST
and NMKL

Advantages

  • Very competitive price (cost per test)
  • All reagents stable for > 2 years after preparation
  • Glutamate dehydrogenase solution stable at -20°C
  • No wasted diaphorase solution (stable suspension supplied)
  • Rapid reaction
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included
  • Suitable for manual, microplate and auto-analyser formats

Q1. What level of cysteine in test samples will affect the results obtained from K-GLUT?

Samples that contain cysteine levels higher than 1 mM will not generate results within the required specification for the K-GLUT assay.

Q2. Should the pH of the sample be adjusted even for samples in acidic media?

The pH of the assay solution after the sample is added should be the same as that of the assay buffer that is supplied with the kit.
Low sample volumes (e.g. 0.1 mL) are not likely to affect the pH of the assay solution and therefore may not require pH adjustment.
Samples above 0.1 mL are more likely to affect the pH of the assay solution and therefore the pH of these samples should be adjusted as described in the data booklet, prior to addition to the assay.

Q3. There is an issue with the performance of the kit; the results are not as expected.

If you suspect that the Megazyme test kit is not performing as expected such that expected results are not obtained please do the following:

  1. Ensure that you have tested the standard sample that is supplied with the Megazyme test kit.
  2. Send the results of the kit standard, blank samples and the results obtained for your sample, in the relevant MegaCalc spreadsheet (if available) to Megazyme (cs@megazyme.com). Where available the relevant MegaCalc spreadsheet can be downloaded from where the product appears on the Megazyme website.
  3. State the kit lot number being used (this is found on the outside of the kit box).
  4. State which assay format was used (refer to the relevant page in the kit booklet if necessary).
  5. State exact details of any modifications to the standard procedure that is provided by Megazyme.
  6. State the sample type and describe the sample preparation steps if applicable.

Q4. How can I work out how much sample to extract and what dilution of my sample should be used in the kit assay?

Where the amount of analyte in a liquid sample is unknown, it is recommended that a range of sample dilutions are prepared with the aim of obtaining an absorbance change in the assay that is within the linear range.
Where solid samples are analysed, the weight of sample per volume of water used for sample extraction/preparation can be altered to suit, as can the dilution of the extracted sample prior to the addition of the assay, as per liquid samples.

Q5. I have some doubts about the appearance/quality of a kit component what should be done?

If there are any concerns with any kit components, the first thing to do is to test the standard sample (control sample) that is supplied with the kit and ensure that the expected value (within the accepted variation) is obtained before testing any precious samples. This must be done using the procedure provided in the kit booklet without any modifications to the procedure. If there are still doubts about the results using the standard sample in the kit then send example results in the MegaCalc spread sheet to your product supplier (Megazyme or your local Megazyme distributor).

Q6. Can the sensitivity of the kit assay be increased?

For samples with low concentrations of analyte the sample volume used in the kit assay can be increased to increase sensitivity. When doing this the water volume is adjusted to retain the same final assay volume. This is critical for the manual assay format because the assay volume and sample volume are used in the calculation of results.

Q7. How much sample should be used for the clarification/extraction of my sample?

The volume/weight of sample and total volume of the extract can be modified to suit the sample. This will ultimately be dictated by the amount of analyte of interest in the sample and may require empirical determination. For low levels of analyte the sample:extract volume ratio can be increased (i.e. increase the sample and/or decrease the total extraction volume).

Alternatively, for samples with low concentrations of analyte, a larger sample volume can be added to the kit assay. When altering the sample volume adjust the distilled water volume added to the assay accordingly so that the total assay volume is not altered.

Q8. Can the test kit be used to measure biological fluids and what sample preparation method should be used?

The kit assay may work for biological fluids assuming that inositol is present above the limit of detection for the kit after any sample preparation (if required). Centrifugation of the samples and use of the supernatant directly in the kit assay (with appropriate dilution in distilled water) may be sufficient. However, if required a more stringent sample preparation method may be required and examples are provided at the following link:http://www.megazyme.com/docs/analytical-applications-downloads/biological_samples_111109.pdf?sfvrsn=2

The test kit has not been tested using biological fluids as samples because it is not marketed or registered as a medical device. This will therefore require your own validation.

Q9. Can the manual assay format be scaled down to a 96-well microplate format?

The majority of the Megazyme test kits are developed to work in cuvettes using the manual assay format, however the assay can be converted for use in a 96-well microplate format. To do this the assay volumes for the manual cuvette format are reduced by 10-fold. The calculation of results for the manual assay format uses a 1 cm path-length, however the path-length in the microplate is not 1 cm and therefore the MegaCalc spreadsheet or the calculation provided in the kit booklet for the manual format cannot be used for the micropalate format unless the microplate reader being used can.

There a 3 main methods for calculation of results using the microplate format:

  1. The easiest method is to use a microplate reader that has a path-length conversion capability (i.e. the microplater reader can detect the path-length of each well and convert the individual readings to a 1 cm path-length). This will allow values to be calculated using the MegaCalc calculation software which can be found where the product is located on the Megazyme website.
  2. Perform a standard curve of the analyte on each microplate that contains test samples and calculate the result of the test samples from the calibration curve (concentration of analyte versus absorbance).
  3. Perform a standard curve of the analyte in both the cuvette format (i.e. with a 1 cm path-length) and the 96-well microplate format and use these results to obtain a mean conversion factor between the cuvette values and the microplate values. Subsequent assays in the microplate format can then be converted from the calculated conversion factor.

Q10. When using this kit for quantitative analysis what level of accuracy and repeatability can be expected?

The test kit is extremely accurate – at Megazyme the quality control criteria for accuracy and repeatability is to be within 2% of the expected value using pure analytes.

However, the level of accuracy is obviously analyst and sample dependent.

Q11. Absorbance values of my sample reactions continue to increase slowly after the reaction should be complete. Is there an explanation for this?

Some samples can react with the INT in the assay and cause a non-enzymatic creep reaction.

The 3rd worksheet in the MegaCalc is used to account for any creep reaction in your results. 

Q12. Must the minimum absorbance change for a sample always be at least 0.1?

No. The 0.1 change of absorbance is only a recommendation. The lowest acceptable change in absorbance can is dictated by the analyst and equipment (i.e. pipettes and spectrophotometer) and therefore can be can be determined by the user. With accurate pipetting, absorbance changes as low as 0.02 can be used accurately.
If a change in absorbance above 0.1 is required but cannot be achieved due to low concentrations of analyte in a sample, this can be overcome by using a larger sample volume in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results. 

Q13. Can the sensitivity of the kit assay be increased?

Yes. Samples with the lower concentrations of analyte will generate a lower absorbance change. For samples with low concentrations of analyte, a larger sample volume can be used in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results.

hPSC解离溶液


产品编号 产品名称 产品规格 产品等级 产品价格
160-27051 hPSC Dissociation Solution 100ml 细胞培养用
197-17571 StemSure hPSC Medium Δ 100ml 细胞培养用
193-17573 StemSure hPSC Medium Δ 100ml×4 细胞培养用
064-05381 Fibroblast Growth Factor (basic), Human, recombinant,Animal-derived-free【bFGF/FGF2】 50μg 细胞生物学用
068-05384 Fibroblast Growth Factor (basic), Human, recombinant,Animal-derived-free【bFGF/FGF2】 100μg 细胞生物学用
060-05383 Fibroblast Growth Factor (basic), Human, recombinant,Animal-derived-free【bFGF/FGF2】 1mg 细胞生物学用
257-00511 Y-27632 1mg 细胞生物学用
253-00513 Y-27632 5mg 细胞生物学用
251-00514 Y-27632 25mg 细胞生物学用
253-00591 5 mmol/L Y-27632 Solution 300μl 细胞培养用
220-02041 Vitronectin(20-398 aa), Human, recombinant, Solution 500μg 生化学用
197-16275 StemSure D-MEM (High Glucose) with Phenol Red and Sodium Pyruvate 500ml 细胞培养用
197-16775 StemSure Serum Replacement (SSR) 500ml 细胞培养用
198-15781 StemSure 10 mmol/L 2-Mercaptoethanol Solution ( x 100) 100ml 细胞培养用
195-15791 StemSure 50 mmol/L Monothioglycerol Solution ( x 100) 100ml 细胞培养用
190-15805 StemSure(R) 0.1w/v% Gelatin Solution 500ml 细胞培养用
199-16051 StemSureR LIF, Mouse, recombinant, Solution 106units 细胞培养用
195-16053 StemSureR LIF, Mouse, recombinant, Solution 106units×10 细胞培养用
195-16031 StemSure Freezing Medium 100ml 细胞培养用

hPSC解离溶液hPSC解离溶液

人多功能干细胞用细胞分散溶液 提供评价用样本!


hPSC解离溶液



  本品是在无饲养层培养条件下培养人ES/iPS继代细胞是使用的细胞分散溶液,不含动物或者人类来源物质,也未使用胰蛋白酶和胶原酶等酶。请与StemSure® hPSC培养基Δ结合使用。另外,Wako还准备了评价用样本(10ml),如有需要,请填写表格申请。


◆特点


  ●无饲养层培养用

  ●不含酶

  ●无动物来源成分

  ●添加有Y-27632可用于单细胞继代培养

 

 

测试项目

  ●无菌测试

  ●pH

  ●渗透压

  ●内毒素

  ●支原体测试


使用方法


<在使用6孔板时>

  1.   清除培养基,用D-PBS(-)清洗细胞

  2.   清除D-PBS(-),将1ml/well本品加进孔板

  3.   7℃,5%CO2条件下,培养5分钟

  4.   敲击剥离细胞群

  5.   加入2ml/well的ROCKi+培养基,通过移液枪吹散细胞群为单细胞。

      (ROCKi+培养基:指在人iPS细胞用培养基中加入Y-27632,使最终浓度变为10μmol/l的培养基。)

  6.   将分散液移至离心管,室温下1,000rpm离心3分钟。

  7.   去除上清。

  8.   继代培养时,添加2ml/wellROCKi+培养基,悬浮,种植。

  9.   冻存时,用StemSure®冻存液悬浮,分装到保存用离心管,冻存。


〔使用注意事项〕

  由于细胞种类和涂层剂的不同,会使培养容器中的细胞粘着性有所不同,,用hPSC解离溶液处理至敲击能使细胞剥离。

 


人iPS细胞的细胞分散

  StemSure® hPSC培养基Δ培养的人iOS细胞201B7株,添加hPSC解离溶液,观察细胞的解离状态。添加hPSC解离溶液5分钟后敲击,移液枪吹散细胞为单细胞


hPSC解离溶液



iPS细胞的继代

  用StemSure® hPSC培养基Δ和hPSC解离溶液对iPS细胞201B7株进行继代培养,细胞增殖能力可到6继代后,各种未分化Marker(Oct3/4, Nanog, rBC2LCN)的表达呈阳性。



《 細胞増殖能力 》



hPSC解离溶液


  〔細胞株〕
    人iPS细胞201B7株

  〔培养基组份〕
    StemSure® hPSC培养基Δ + 35ng/ml bFGF

  〔涂层剂〕
    Matrigel® hESC-Qualified Matrix 

  〔细胞种植数〕
    1.0×105 cells/well (使用6孔板)

 

《未分化性维持》



hPSC解离溶液



 

相关产品


液体培养基・细胞培养用试剂★   

Wako提供液体培养基、平衡盐溶液、细胞剥离·分散溶液、抗生物质溶液、细胞外基质等丰富的产品种类。


ES・iPS细胞研究用试剂★ 
  2007年,建立iPS细胞的消息发布之后,与iPS细胞相关的许多文章相继发表。在这些发表的文章中,也罗列了与ES细胞·iPS细胞未分化能维持、分化诱导相关的低分子化合物。


LIF, 人, 重组人体, 培养上清★ 
  LIF具有抑制小鼠ES细胞分化的作用,因此在细胞培养时,它可用于维持ES细胞的未分化状态。


rBC2LCN★ 
  rBC2LCN可识别人ES细胞·人iPS细胞。通过加入含有人ES细胞·人iPS细胞的营养液,可给未分化细胞活体染色。

 

乳果糖检测试剂盒 Lactulose Assay Kit 货号:K-LACTUL Megazyme中文站

乳果糖检测试剂盒

英文名:Lactulose Assay Kit

货号:K-LACTUL

规格:50 assays

Megazyme乳果糖检测试剂盒采用酶法分析原理,可定量检测鲜奶、UHT奶、浓缩乳和奶粉等各种乳品中的乳果糖。与农业部新标准采用相同的检测原理和方法该试剂盒采用ISO方法11285:2004,经过改进后,更加快速和灵敏灵敏度是传统己糖激酶法的两倍成本低试剂配制后可稳定保存2年采用试剂盒形式,包含检测必需的所有酶提供计算软件,使数据处理更方便包含标准品

The Lactulose Assay Kit is suitable for the specific, rapid and sensitive measurement and analysis of lactulose in milk and milk-based samples. Reagents included in this kit may also be prepared for use in the procedure described by ISO Method 11285:2004.

UV-method for the determination of Lactulose in milk and
foodstuffs containing dairy products

Principle:
(β-galactosidase)
(1) Lactulose + H2O → D-galactose + D-fructose

(glucose oxidase + catalase + H2O2)
(2) D-Glucose + H2O + O2 → D-gluconic acid + H2O2

(hexokinase)
(3) D-Fructose + ATP → F-6-P + ADP

(phosphoglucose isomerase)
(4) F-6-P → G-6-P

(glucose-6-phosphate dehydrogenase)
(5) G-6-P + NADP+ → gluconate-6-phosphate + NADPH + H+

(gluconate-6-phosphate dehydrogenase)
(6) Gluconate-6-phosphate + NADP+ → ribulose-5-phosphate + NADPH
+ CO2 + H+

Kit size: 50 assays
Method: Spectrophotometric at 340 nm
Reaction time: ~ 120 min
Detection limit: 4.8 mg/L
Application examples:
Milk, dairy products and foods containing milk
Method recognition: Novel method

Advantages

  • Twice the sensitivity of traditional hexokinase based lactulose methods
  • Very cost effective
  • All reagents stable for > 2 years after preparation
  • Mega-Calc™ software tool is available from our website for hassle-free raw data processing
  • Standard included

 Q1. Sometimes a negative absorbance change is obtained for the blank samples, is this normal? Should the real value (negative absorbance change) or “0” be used in the calculation of results?

Sometimes the addition of the last assay component can cause a small negative absorbance change in the blank samples due to a dilution effect and in such cases it is recommended that the real absorbance values be used in the calculation of results.

Q2. Some samples generate values of A2 – A1 greater than 0.3?

Samples that generate absorbance values A2 – A1 of 0.3 should be diluted in distilled water prior to the Sample Preparation (section A, page 7) and the second incubation of step 2 increased (glucose oxidase / catalase) to 30 min. 

Q3. What are the critical steps of the K-LACTUL assay kit?

Some critical steps of the assay are as follows:
A2 should be read after approximately 10 min and you should ensure that the reaction has finished, i.e. measure the absorbance until it stops increasing.  (Slight increases in absorbance of 0.001/min or less are acceptable).
The supernatants from both steps (1 and 2) of A. Sample Preparation should be clear. 

Q4. Can the K-LACTUL kit be used to measure samples other than milk-based samples?

The K-LACTUL kit will measure lactulose in most samples however it is the sample preparation prior to the Enzymatic Determination Reaction that is important. Megazyme has only tested milk-based samples, however most samples that do not contain high protein levels may work using the same standard procedure as described in the K-LACTUL data booklet. Samples containing very high levels of free fructose may not work.

Q5. Should the pH of the sample be adjusted even for samples in acidic media?

The pH of the assay solution after the sample is added should be the same as that of the assay buffer that is supplied with the kit.
Low sample volumes (e.g. 0.1 mL) are not likely to affect the pH of the assay solution and therefore may not require pH adjustment.
Samples above 0.1 mL are more likely to affect the pH of the assay solution and therefore the pH of these samples should be adjusted as described in the data booklet, prior to addition to the assay.

Q6. There is an issue with the performance of the kit; the results are not as expected.

If you suspect that the Megazyme test kit is not performing as expected such that expected results are not obtained please do the following:

  1. Ensure that you have tested the standard sample that is supplied with the Megazyme test kit.
  2. Send the results of the kit standard, blank samples and the results obtained for your sample, in the relevant MegaCalc spreadsheet (if available) to Megazyme (cs@megazyme.com). Where available the relevant MegaCalc spreadsheet can be downloaded from where the product appears on the Megazyme website.
  3. State the kit lot number being used (this is found on the outside of the kit box).
  4. State which assay format was used (refer to the relevant page in the kit booklet if necessary).
  5. State exact details of any modifications to the standard procedure that is provided by Megazyme.
  6. State the sample type and describe the sample preparation steps if applicable.

Q7. Is it possible to check where issues in the measurement of lactulose may be occurring?

If it is suspected that the measurements of K-LACTUL are not correct and there is doubt regarding the performance of the kit then the following steps should be checked.
1. Check that the cuvettes are 1.5 mL microcuvettes and that the volume of the liquid in the cuvettes is high enough for the spectrophotometer.
2. Check the temperature of the reactions is correct.
Using the standard lactulose/fructose solution (bottle 8) that is supplied with the kit will help determine where issues are occurring with the measurement of lactulose samples.  The obvious steps where issues may occur are: A. Sample Preparation (page 7 K-LACTUL booklet) and B. Enzymatic Determination Reaction (page 8 K-LACTUL booklet).
3. The performance of K-LACTUL can be tested as follows:
(A. Sample Preparation (page 7 K-LACTUL booklet)
Use 0.5 mL of the standard lactulose /fructose solution (Bottle 8) which contains 0.1 mg/mL lactulose and 0.05 mg/mL fructose.  The typical individual absorbance values are: A1 = 0.2, A2 = 0.2, A3 = 1.0.  This should generate a final absorbance difference of (A3-A2) of approximately 0.8 (Note: this measurement includes the lactulose and fructose measurement and is not just lactulose content only).
Note: If the correct values are obtained for the performance of K-LACTUL then there is no need to check the performance of the Enzymatic Determination Reaction step separately.
4. The performance of the Enzymatic Determination Reaction step can be tested separately as follows:
B. Enzymatic Determination Reaction (page 8 K-LACTUL booklet)
This test uses 0.1 mL of the standard lactulose /fructose solution (Bottle 8) which contains 0.05 mg/mL fructose. This is equivalent to 5 μg of fructose added to the cuvette and should generate an absorbance difference (A3-A2) of approximately 0.3. If this absorbance difference is obtained then it can be concluded that the step is performing correctly.
B. ENZYMATIC DETERMINATION REACTION:
Wavelength: 340 nm
Cuvette: 1 cm light path (glass or plastic; 1.5 mL semi-micro)
Final volume: 1.16 mL
Sample solution: 0.65-65 μg of lactulose per cuvette (in 0.1-1.0 mL sample volume)
Read against air (without cuvette in the light path) or against water Pipette

Pipette into cuvettes

Sample

Blank

standard 8 (lactulose/fructose solution)

distilled water

solution 3 (imidazole buffer)

solution 4 (NADP+/ATP)

0.10 mL

0.90 mL

0.05 mL

0.05 mL

1.00 mL

0.05 mL

0.05 mL

Mix*, read absorbance of the solutions (A1) after approx. 3 min and start the reactions by addition of:

suspension 5 (HK/G-6-PDH)

suspension 6 (6-PGDH)

0.02 mL

0.02 mL

0.02 mL

0.02 mL

Mix*, read absorbance of the solutions (A2) at the end of the reaction (approx. 10 min).  Then add:

suspension 7 (PGI)

0.02 mL

0.02 mL

Mix*, read absorbance of the solutions (A3) at the end of the reaction (approx. 15 min).

* for example with a plastic spatula or by gentle inversion after sealing the cuvette with a cuvette cap or Parafilm®. 

Q8. How can I work out how much sample to extract and what dilution of my sample should be used in the kit assay?

Where the amount of analyte in a liquid sample is unknown, it is recommended that a range of sample dilutions are prepared with the aim of obtaining an absorbance change in the assay that is within the linear range.
Where solid samples are analysed, the weight of sample per volume of water used for sample extraction/preparation can be altered to suit, as can the dilution of the extracted sample prior to the addition of the assay, as per liquid samples.

Q9. I have some doubts about the appearance/quality of a kit component what should be done?

If there are any concerns with any kit components, the first thing to do is to test the standard sample (control sample) that is supplied with the kit and ensure that the expected value (within the accepted variation) is obtained before testing any precious samples. This must be done using the procedure provided in the kit booklet without any modifications to the procedure. If there are still doubts about the results using the standard sample in the kit then send example results in the MegaCalc spread sheet to your product supplier (Megazyme or your local Megazyme distributor).

Q10. Can the sensitivity of the kit assay be increased?

For samples with low concentrations of analyte the sample volume used in the kit assay can be increased to increase sensitivity. When doing this the water volume is adjusted to retain the same final assay volume. This is critical for the manual assay format because the assay volume and sample volume are used in the calculation of results.

Q11. Can the test kit be used to measure biological fluids and what sample preparation method should be used?

The kit assay may work for biological fluids assuming that inositol is present above the limit of detection for the kit after any sample preparation (if required). Centrifugation of the samples and use of the supernatant directly in the kit assay (with appropriate dilution in distilled water) may be sufficient. However, if required a more stringent sample preparation method may be required and examples are provided at the following link:http://www.megazyme.com/docs/analytical-applications-downloads/biological_samples_111109.pdf?sfvrsn=2

The test kit has not been tested using biological fluids as samples because it is not marketed or registered as a medical device. This will therefore require your own validation.

Q12. Can the manual assay format be scaled down to a 96-well microplate format?

The majority of the Megazyme test kits are developed to work in cuvettes using the manual assay format, however the assay can be converted for use in a 96-well microplate format. To do this the assay volumes for the manual cuvette format are reduced by 10-fold. The calculation of results for the manual assay format uses a 1 cm path-length, however the path-length in the microplate is not 1 cm and therefore the MegaCalc spreadsheet or the calculation provided in the kit booklet for the manual format cannot be used for the micropalate format unless the microplate reader being used can.

There a 3 main methods for calculation of results using the microplate format:

  1. The easiest method is to use a microplate reader that has a path-length conversion capability (i.e. the microplater reader can detect the path-length of each well and convert the individual readings to a 1 cm path-length). This will allow values to be calculated using the MegaCalc calculation software which can be found where the product is located on the Megazyme website.
  2. Perform a standard curve of the analyte on each microplate that contains test samples and calculate the result of the test samples from the calibration curve (concentration of analyte versus absorbance).
  3. Perform a standard curve of the analyte in both the cuvette format (i.e. with a 1 cm path-length) and the 96-well microplate format and use these results to obtain a mean conversion factor between the cuvette values and the microplate values. Subsequent assays in the microplate format can then be converted from the calculated conversion factor.

Q13. How much sample should be used for the clarification/extraction of my sample?

The volume/weight of sample and total volume of the extract can be modified to suit the sample. This will ultimately be dictated by the amount of analyte of interest in the sample and may require empirical determination. For low levels of analyte the sample:extract volume ratio can be increased (i.e. increase the sample and/or decrease the total extraction volume).

Alternatively, for samples with low concentrations of analyte, a larger sample volume can be added to the kit assay. When altering the sample volume adjust the distilled water volume added to the assay accordingly so that the total assay volume is not altered.

Q14. When using this kit for quantitative analysis what level of accuracy and repeatability can be expected?

The test kit is extremely accurate – at Megazyme the quality control criteria for accuracy and repeatability is to be within 2% of the expected value using pure analytes.

However, the level of accuracy is obviously analyst and sample dependent.

Q16. Can the sensitivity of the kit assay be increased?

Yes. Samples with the lower concentrations of analyte will generate a lower absorbance change. For samples with low concentrations of analyte, a larger sample volume can be used in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results.

Q15. Must the minimum absorbance change for a sample always be at least 0.1?

No. The 0.1 change of absorbance is only a recommendation. The lowest acceptable change in absorbance can is dictated by the analyst and equipment (i.e. pipettes and spectrophotometer) and therefore can be can be determined by the user. With accurate pipetting, absorbance changes as low as 0.02 can be used accurately.
If a change in absorbance above 0.1 is required but cannot be achieved due to low concentrations of analyte in a sample, this can be overcome by using a larger sample volume in the assay to increase the absorbance change and thereby increase sensitivity of the assay. When doing this the increased volume of the sample should be subtracted from the distilled water volume that is added to the assay so that the total assay volume is unaltered. The increase sample volume should also be accounted for when calculating final results. 

上海金畔生物科技有限公司提供修饰性PEG分子量清单

PEG修饰剂 活化聚乙二醇 修饰性聚乙二醇:

mPEG-NH2 MW 350
mPEG-NH2 MW 550
mPEG-NH2 MW 750
mPEG-NH2 MW 1000
mPEG-NH2 MW 2000
mPEG-NH2 MW 5000
mPEG-COOH MW 1000
mPEG-COOH MW 2000
mPEG-COOH MW 5000
mPEG-SH MW 1000
mPEG-SH MW 2000
mPEG-SH MW 5000
mPEG-SPA MW 1000
mPEG-SPA MW 2000
mPEG-SPA MW 5000
mPEG-Mal MW 5000
mPEG-ALD MW 2000
mPEG-ALD MW 5000
mPEG-SCM MW 1000
mPEG-SCM MW 2000
mPEG-SCM MW 5000
mPEG-Hydrazide MW 2000
mPEG-Hydrazide MW 5000
mPEG-DSPE MW 2000
mPEG-Silane MW 2000
NH2-PEG-NH2 MW 300
NH2-PEG-NH2 MW 600
NH2-PEG-NH2 MW 1000
NH2-PEG-NH2 MW 2000
NH2-PEG-NH2 MW 3400
NH2-PEG-NH2 MW 4000
COOH-PEG-COOH MW 1000
COOH-PEG-COOH MW 2000
MAL-PEG-MAL MW 2000
MAL-PEG-MAL MW 4000
NHS-PEG-NHS MW 3400
NH2-PEG-COOH MW 1000
NH2-PEG-COOH MW 2000
NH2-PEG-COOH MW 3400
NH2-PEG-COOH MW 4000
NH2-PEG-OH MW 1000
NH2-PEG-OH MW 2000
NH2-PEG-OH MW 4000
NH2-PEG-SH MW 4000
BOC-NH-PEG-SC MW 5000
BOC-NH-PEG-OH MW 2000
BOC-NH-PEG-NH2 MW 3400
BOC-NH-PEG-NHS MW 2000
Fmoc-NH-PEG-COOH MW 2000
Fmoc-NH-PEG-NHS MW 2000
Biotin-PEG-NH2 MW 3400
Biotin-PEG-NHS MW 2000
Biotin-PEG-SCM MW 4000
Biotin-PEG-OH MW 4000
HO-PEG-COOH MW 2000
Mal-PEG-NHS MW 3400
Mal-PEG-OH MW 2000
Mal-PEG-COOH MW 2000
Folate-PEG-NH2 MW 3400
DSPE-PEG-Mal MW 2000
SH-PEG-SH MW 3400
SH-PEG-COOH MW 3400
NPC-PEG-NPC MW 3400
FITC-PEG-NH2 MW 3400
4-arm-PEG-COOH MW 10000
4-arm-PEG-NH2 MW 10000
4-arm-PEG-SH MW 10000
mPEG-OH MW 2000
mPEG-OH MW 5000
mPEG-OH MW 20000

WHATMAN代理,WHATMAN石英滤纸,WHATMAN径迹蚀刻膜,PALLFLEX滤膜

WHATMAN代理,WHATMAN石英滤纸,WHATMAN径迹蚀刻膜,PALLFLEX滤膜

Whatman1005-047 Grade 5定性滤纸 GR 5 4.7CM 100/PK

【简单介绍】

Whatman定性滤纸用于定性分析技术中鉴定物质的性质。折叠好的定性滤纸与相同型号平整的滤纸相比,加快了流速和增加了负载力,定性滤纸―标准级,Wet Strengthened Grades湿强定性滤纸。湿强定性滤纸含有少量的化学稳定树脂,因而增强了湿强度。这不会因此引入任何明显的杂质到滤液中。但因树脂含氮,这些级别的滤纸不能用于凯氏定氮测定。

【简单介绍】

Whatman定性滤纸用于定性分析技术中鉴定物质的性质。折叠好的定性滤纸与相同型号平整的滤纸相比,加快了流速和增加了负载力,定性滤纸―标准级,Wet Strengthened Grades湿强定性滤纸。湿强定性滤纸含有少量的化学稳定树脂,因而增强了湿强度。这不会因此引入任何明显的杂质到滤液中。但因树脂含氮,这些级别的滤纸不能用于凯氏定氮测定。

【详细说明】

原装进口英国Whatman1005-047 Grade 5定性滤纸 GR 5 4.7CM 100/PK

whatman官网 Whatman滤纸 Whatman滤膜

英国Whatman1005-047Grade 5定性滤纸 GR 5 4.7CM 100/PK

 

简单介绍:

Whatman定性滤纸用于定性分析技术中鉴定物质的性质。折叠好的定性滤纸与相同型号平整的滤纸相比,加快了流速和增加了负载力,定性滤纸―标准级,Wet Strengthened Grades湿强定性滤纸。湿强定性滤纸含有少量的化学稳定树脂,因而增强了湿强度。这不会因此引入任何明显的杂质到滤液中。但因树脂含氮,这些级别的滤纸不能用于凯氏定氮测定。

 

Whatman定性滤纸的详细介绍:

Whatman定性滤纸Grade1/Grade2/Grade3/Grade4/Grade5/Grade6

Whatman定性滤纸用于定性分析技术中鉴定物质的性质。折叠好的定性滤纸与相同型号平整的滤纸相比,加快了流速和增加了负载力。

 

 

定性滤纸―标准级

Grade 1:11μm 在日常过滤中最经常使用的,中等保留力和流速。非常广泛地用于实验室应用,澄清液体。典型地用于沉淀物的定量分析分离,如硫酸铅、草酸钙和碳酸钙。

在农业方面,它用于土壤分析和种子测试;在食品方面,Grade 1滤纸常用于相关液体和抽离液体分离固体食品的常规方法。并且广泛用于教学中简单的定性分析分离。

在空气污染监测方面,有圆片和卷片可供使用,从气流中收集大气灰尘然后用光度计测量;在气体探测中滤纸用发色剂浸湿,用光反射来定量。

 

Grade 2:8μm 比Grade1保留力略强,但过滤时间却相对长些(即过滤速度相对慢些),吸附性比Grade 1强,已折叠好的为Grade 2V。除8μm大小颗粒的普通过滤处,它额外的吸附性能也派上了用场,例如,在植物生长实验中截留土壤营养,也用于监测空气和土壤测试中的特殊污染物。

 

Grade 3:6μm 厚度是Grade 1的两倍。负载力好,颗粒保留较小。由于湿强度好适合放在布氏漏斗中使用。其高吸附性能可用作为样品的载体。

 

Grade 4:20-25μm 非常适用于分析中常规生物液体和有机浸出物澄清的快速过滤,空气污染监测中只要求高流速但对细小颗粒收集要求不严的采样。

 

Grade 5:2.5μm 最高效的定性滤纸,用于收集小颗粒,流速漫。适用化学分析、澄清悬浮物和水泥土分析。

 

Grade 6:3μm 流速是Grade 5的两倍,但颗粒保留度相等。常被指定用于锅炉水分析

whatman官网 Whatman滤纸 Whatman滤膜 Whatman中国官网

 

订货信息–定性标准滤纸
直径(mm) Grade 4 Grade 5 Grade 6 数量/

包装

10 500
23 100
25 1004-325 1005-325 100
30 100
32 100
42.5 1004-042 1005-042 1006-042 100
47 1004-047 1005-047 100
55 1004-055 1005-055 100
70 1004-070 1005-070 1006-070 100
85 100
90 1004-090 1005-090 1006-090 100
110 1004-110 1005-110 1006-110 100
125 1004-125 1005-125 1006-125 100
150 1004-150 1005-150 1006-150 100
185 1004-185 1005-185 1006-185 100
240 1004-240 1005-240 1006-240 100
270 1004-270 100
320 1004-320 1005-320 100
400 1004-400 100
500 100
FilterCup 70* 25

英国沃特曼一级代理_whatman总代理_玻璃微纤维滤纸_纤维素层析纸

whatman官网 Whatman滤纸 Whatman滤膜

*一次性购买带橡胶塞过滤杯底座–货号1600-900

上海金畔生物科技有限公司

文章号20207688-20207688

丙酮酸激酶(兔肌) Pyruvate kinase (rabbit muscle) 货号:E-PKRM Megazyme中文站

丙酮酸激酶(兔肌)

英文名:Pyruvate kinase (rabbit muscle)

货号:E-PKRM

规格:5,000 Units at 37°C

High purity pyruvate kinase (rabbit muscle) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

EC 2.7.1.40
CAS: 9001-59-6

ATP:pyruvate 2-O-phosphotransferase

From rabbit muscle.
In 3.2 M ammonium sulphate.
Supplied at ~ 2,500 U/mL.

Specific activity: 233 U/mg protein at pH 7.2 and 37oC.

Stability: > 2 years 4oC.

暂无问题解答

暂无视频

α-葡萄糖苷酶(嗜热脂肪芽孢杆菌)(重组) α-Glucosidase (Bacillus stearothermophilus) (Recombinant) 货号:E-TSAGS Megazyme中文站

α-葡萄糖苷酶(嗜热脂肪芽孢杆菌)(重组)

英文名:α-Glucosidase (Bacillus stearothermophilus) (Recombinant)

货号:E-TSAGS

规格:3000 Units at 40°C /6000 Units at 60°C

Alpha葡[萄]糖苷酶[嗜热脂肪芽孢杆菌]

EC 3.2.1.20
CAZY Family: GH13
Recombinant from Bacillus stearothermophilus. In 3.2 M ammonium sulphate.
Specific activity: ~ 280 U/mg (60oC, pH 6.5 on p-nitrophenyl-α-D-glucopyranoside); ~ 135 U/mg (40oC, pH 6.5 on p-nitrophenyl-α-D-glucopyranoside).
Action on other substrates: Blocked p-nitrophenol maltoheptaoside < 0.0001 %
Stability: > 4 years at 4oC.

 

暂无问题解答

暂无视频

BINKIT® NK细胞扩增套装(外周血单核细胞来源)


产品编号 产品名称 产品规格 产品等级 产品价格
BIJ-N501-1 BINKIT® for NK cells expansion from PBMCs 
BINKIT ®  NK细胞增殖套装(外周血单核细胞来源)
1 kit
BIJ-N501-2 BINKIT® for NK cells expansion from PBMCs 
BINKIT ®  NK细胞增殖套装(外周血单核细胞来源)
2 kits
BIJ-N501-4 BINKIT® for NK cells expansion from PBMCs 
BINKIT ®  NK细胞增殖套装(外周血单核细胞来源)
4 kits
BIJ-N501-8 BINKIT® for NK cells expansion from PBMCs 
BINKIT ®  NK细胞增殖套装(外周血单核细胞来源)
8 kits

BINKIT® NK细胞扩增套装(外周血单核细胞来源)

BINKIT® NK细胞扩增套装(外周血单核细胞来源)

 

◆原理

 

  BINKIT® 可从外周血单核细胞扩增高活性的自然杀伤(NK)细胞。

 


◆优点・特色

 

● 无需饲养层细胞,即可从外周血细胞 (PBMCs)中扩增NK细胞

 3周时间内NK细胞的数目可扩增几百到几千倍

 NK细胞将获得增强的细胞杀伤性

 该试剂盒适合20~50mL的外周血细胞

 Xeno-free(不含动物来源的材料)

 

 

◆案例・应用

 

<试剂盒组成>

 NK 细胞初始培养基

 NK细胞初始培养瓶

 NK细胞传代培养基

 BINKIT® 明细表(PDF格式)

 

<未提供材料>

 Ficoll 淋巴细胞分层液(GE Healthcare)

 无菌PBS

 FBS或自体血浆(56℃加热30分钟以灭活)

 

<结果>


BINKIT® NK细胞扩增套装(外周血单核细胞来源)

 

图 1 使用BINKIT® 进行体外NK细胞扩增

利用BINKIT® 对外周血单核细胞进行NK细胞扩增,CD3-CD56+细胞从15.8%增加到88.6%。


 BINKIT® NK细胞扩增套装(外周血单核细胞来源)

图 2 使用BINKIT® 进行体外NK细胞扩增

利用BINKIT® 对外周血单核细胞(来自健康自愿者,HD, n=3)进行NK细胞扩增。

细胞计数(左)和倍率的变化(右)表明NK细胞体在外高效扩增。

 


BINKIT® NK细胞扩增套装(外周血单核细胞来源) 

图3  使用BINKIT® 进行体外NK细胞扩增

分别以BINKIT扩增的NK细胞(实线)和从3名志愿者新鲜分离的NK细胞(虚线)来检测NK细胞对K562细胞的杀伤性。

结果表明,扩增后的NK细胞对K562细胞杀伤性显著增强(P<0.01)。

 

<培养步骤>

(1) 准备试剂

在NK细胞初始培养基和NK细胞传代培养基中,加入5% (v/v) 的热灭活FBS或自体血浆。

 

(2) 制备外周血单核细胞(PBMCs)

通过Ficoll密度梯度离心,从人全血中分离外周血单核细胞。

 

(3)清洗NK细胞初始培养瓶

加入10毫升PBS至NK细胞初始培养瓶。倾斜培养瓶使PBS覆盖整个表面。

将培养瓶中液体全部倒出,小心以免刮伤培养瓶的表面。重复洗涤过程两次。

 

(4)从PBMCs中培养NK细胞

将1×106 cells/mL 的PBMCs 悬浮于NK细胞初始培养基中。每1 mL 细胞悬浮液加入40 μL的NK细胞初始混合物。

细胞悬液转移至预洗涤的NK细胞初始培养瓶,在37℃,5%的CO2培养3天。

 

(5)更换培养基及传代

同贴壁细胞处理一样,转移时置于锥形离心管,200×g离心8分钟。

去除上清,将1×106 cells/mL 的NK细胞悬浮于传代培养基中,培养基内加入5mL

转移后的悬浮细胞置于常规培养瓶中,在37℃,5% CO2条件下培养。

每2-3天将 0.8×106 cells/mL 细胞置于完全NK细胞传代培养基中,进行传代培养。

 

<建议培养期>

2 – 3 周

 

注意:试剂仅供科研使用,不可用于临床。 

 

<参考文献>
Xuewen Deng, Hiroshi Terunuma, Mie Nieda, Weihua Xiao, Andrew Nicol,
Synergistic cytotoxicity of ex vivo expanded natural killer cells in combination with monoclonal antibody drugs against cancer cells,
Int Immunopharmacol 14 (2012) 593-605
PMID: 23063974

1,4-β-D-Cellopentaitol (borohydride reduced cellopentaose) 1,4-β-D-Cellopentaitol (borohydride reduced cellopentaose) 货号:O-CPERD Megazyme中文站

1,4-β-D-Cellopentaitol (borohydride reduced cellopentaose)

英文名:1,4-β-D-Cellopentaitol (borohydride reduced cellopentaose)

货号:O-CPERD

规格:30 mg

CAS: 61473-65-2
Molecular Formula: C30H54O26
Molecular Weight: 830.7
Purity: > 95%

High purity 1,4-β-D-Cellopentaitol (borohydride reduced cellopentaose) for use in research, biochemical enzyme assays and in vitro diagnostic analysis.

Pentasaccharide from hydrolysis of cellulose and borohydride reduced.

Store at room temperature.

暂无问题解答

暂无视频