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Human Leptin ELISA Kit PicoKine™
Human Leptin ELISA Kit PicoKine™ (96 Tests). Quantitate Human LEP in cell culture supernatants, cell lysates, serum and plasma (heparin, EDTA).. Sensitivity: 10pg/ml. Cited in 25 publication(s).
Human Leptin ELISA Kit PicoKine™ Product Summary
| SKU: | EK0437 |
|---|---|
| Size: | 96 wells/kit, with removable strips. |
| Reactivity: | Human |
| Sample Type: | cell culture supernatants, cell lysates, serum and plasma (heparin, EDTA). |
| Sample Volume: | 100μl per well |
| Sensitivity: | <10 pg/ml |
| Assay Range: | 62.5 pg/ml - 4,000 pg/ml |
Overview
| Product Name | Human Leptin ELISA Kit PicoKine™ |
|---|---|
| Catalog# | EK0437 |
| Storage & Handling | Store at 4°C for 6 months, at -20°C for 12 months. Avoid multiple freeze-thaw cycles (Shipped with wet ice.) |
| Description | Human Leptin ELISA Kit PicoKine™ (96 Tests). Quantitate Human LEP in cell culture supernatants, cell lysates, serum and plasma (heparin, EDTA).. Sensitivity: 10pg/ml. |
| Cite This Product | Human Leptin ELISA Kit PicoKine™ (Boster Biological Technology, Pleasanton CA, USA, Catalog # EK0437) |
| ELISA Validation | ELISA Validation Information |
Product Specs
| Reactivity/Species | Human |
|---|---|
| Applications | ELISA
*Our Boster Guarantee covers the use of this product in the above tested applications. **For positive and negative control design, consult "Tissue specificity" under "Protein Target Info" tab. |
| Sample Type | cell culture supernatants, cell lysates, serum and plasma (heparin, EDTA). |
| Sensitivity | <10 pg/ml |
| Assay Range | 62.5 pg/ml - 4,000 pg/ml |
| Immunogen/Standard | Expression system for standard: E.coli; Immunogen sequence: V22-C167 |
| Antibody Clonalities | Capture antibody|Detection antibody monoclonal antibody from mouse|polyclonal antibody from goat |
| Cross Reactivity | There is no detectable cross-reactivity with other relevant proteins. |
| Pack Size | 96 wells/kit, with removable strips. |
Gene/Protein Basic Information For LEP (Source: Uniprot.org, NCBI)
| Uniprot Id | A4D0Y8 |
|---|---|
| Gene Name | LEP |
| Molecular Weight | 18641 MW |
*if product is indicated to react with multiple species, protein info is based on the gene entry specified above in "species".
For more info on LEP, check out the LEP Infographic
We have 30,000+ of these available, one for each gene! Check them out.
Want a nice infographic on your next protein? Boster's got them all. All proteins in the human genome, and some, can be found in the Boster Bio gene infographics. Download it and share it with your colleagues and friends. Big size posters available upon request.
In this infographic you will see the following information for LEP: database IDs, super-family, protein function, synonyms, molecular weight, chromosomal locations, tissues of expression, subcellular locations, post translational modifications, and related diseases, research areas & pathways. Some times it even contains some opt-ed articles the Boster team on the scientific news and clinical impacts of this protein, though not all have that. Too many proteins, you know.
Kit Components And Assay QC Data Details Of Human Leptin ELISA Kit PicoKine™
*The quality control (QC) data in this section is obtained from Boster's internal QC results and is for reference only. It may differ from the users' lab test results. The users can expect to generate data with similar linearity and quality demonstrated in the typical data but may not achieve exactly the same O.D. values.
| Catalog number | Description | Quantity |
|---|---|---|
| EK0437-CAP | Anti-Human LEP Pre-coated 96-well strip microplate | 1 |
| EK0437-ST | Human LEP Standard | 2 vials, 10 ng/tube |
| EK0437-DA | Human LEP Biotinylated antibody (100x) | 100ul |
| AR1103 | Avidin-Biotin-Peroxidase Complex (100x) | 100ul |
| AR1106-1 | Sample Diluent | 30ml |
| AR1106-2 | Antibody Diluent | 12ml |
| AR1106-3 | Avidin-Biotin-Peroxidase Diluent | 12ml |
| AR1104 | Color Developing Reagent (TMB) | 10ml |
| AR1105 | Stop Solution | 10ml |
| AR1106-5 | Wash Buffer (25x) | 20ml |
| PLA-SEA | Adhesive plate sealers | 4 |
*The kit components are not available for individual purchase.
- Microplate Reader capable of reading absorbance at 450nm.
- Automated plate washer (optional).
- Pipettes and pipette tips capable of precisely dispensing 0.5 µl through 1 ml volumes of aqueous solutions.
- Multichannel pipettes are recommended for large amount of samples.
- Deionized or distilled water.
- 500ml graduated cylinders.
- Test tubes for dilution.
This data is generated from a recent batch of EK0437 Human Leptin ELISA Kit PicoKine™. It is not necessarily the same data set used to generate the standard curve shown in the image of this product. TMB reaction incubate at 37°C for 15-25min
| Concentration (pg/ml) | 0 | 62.5 | 125 | 250 | 500 | 1000 | 2000 | 4000 |
| O.D. | 0.002 | 0.036 | 0.080 | 0.191 | 0.505 | 0.923 | 1.801 | 2.461 |
We measured random samples of Human Leptin ELISA Kit PicoKine™ within the same batch/lot to ensure the consistency of the kits' performances. ELISA intra assay consistency is measured using wells from the same plate/assay kit. ELISA inter assay consistency is measured using wells from different plates from the same batch production/lot.
| Intra-Assay Precision | Inter-Assay Precision | |||||
|---|---|---|---|---|---|---|
| Sample | 1 | 2 | 3 | 1 | 2 | 3 |
| n | 16 | 16 | 16 | 24 | 24 | 24 |
| Mean (pg/ml) | 81 | 485 | 1057 | 75 | 444 | 996 |
| Standard deviation | 6.15 | 32.49 | 54.96 | 8 | 35.52 | 69.72 |
| CV (%) | 7.6% | 6.7% | 5.2% | 8.4% | 8% | 7% |
We measured the performance consistency of Human Leptin ELISA Kit PicoKine™ to ensure the reproducibility of the assays. Three samples with differing target protein concentrations were assayed using four different lots.
Reproducibility
To assay reproducibility, three samples with differing target protein concentrations were assayed using four different lots.
| Lots | Lot 1 (pg/ml) | Lot 2 (pg/ml) | Lot 3 (pg/ml) | Lot 4 (pg/ml) | Mean (pg/ml) | Standard Deviation | CV (%) |
|---|---|---|---|---|---|---|---|
| Sample 1 | 81 | 83 | 84 | 87 | 83 | 2.16 | 2.6% |
| Sample 2 | 485 | 539 | 463 | 476 | 490 | 28.93 | 5.9% |
| Sample 3 | 1057 | 1101 | 1114 | 1116 | 1097 | 23.8 | 2.1% |
Specific Protocols
Boster provides comprehensive technical information for WB, IHC/IF/ICC, Flow Cytometry sample preparation protocols, assay protocols, troubleshooting tips and assay optimization tips.
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Total number of citations: 25
| Turan S,Sarioglu FC,Erbas IM,Cavusoglu B,Karagöz E,Şişman AR,Güney SA,Güleryüz H,Abaci A,Ozturk Y,Akay AP. Altered regional grey matter volume and appetite-related hormone levels in adolescent obesity with or without binge-eating disorder. Eat Weight Diso Species: Human EK0437 usage in article: APP:ELISA, SAMPLE:SERUM, DILUTION:NA |
PubMed ID 33548051 |
| Leptin partially mediates the association between early-life nutritional supplementation and long-term glycemic status among women in a Guatemalan longitudinal cohort | PubMed ID 32069352 |
| Adipokines, psoriasis, systemic inflammation, and endothelial dysfunction | PubMed ID 28762474 |
| Investigation of adropin and leptin levels in pediatric obesity-related nonalcoholic fatty liver disease. | PubMed ID 24468600 |
| Leptin levels in gingival crevicular fluid during canine retraction: in vivo comparative study | PubMed ID 31056072 |
| The relation of leptin and soluble leptin receptor levels with metabolic and clinical parameters in obese and healthy children. | PubMed ID 24703965 |
| Leptin concentration and oxidative stress in diabetic ketoacidosis. | PubMed ID 30053313 |
| Increased concentrations of serum nesfatin-1 levels in childhood with idiopathic chronic malnutrition | PubMed ID 29714458 |
| Perilipin polymorphisms are risk factors for the development of obesity in adolescents? A case-control study | PubMed ID 28274232 |
| The Relationship between Serum Zonulin Level and Clinical and Laboratory Parameters of Childhood Obesity | PubMed ID 28008865 |
| The effect of vitamin D administration on serum leptin and adiponectin levels in end-stage renal disease patients on hemodialysis with vitamin D deficiency: A placebo-controlled double-blind clinical trial | PubMed ID 27904547 |
| Elective percutaneous coronary intervention leads to significant changes in serum resistin, leptin, and adiponectin levels regardless of periprocedural myocardial injury: an observational study | PubMed ID 27443475 |
| Altay C, Se?il M, Demir T, Atik T, Ak?nc? G, ?zdemir Kutbay N, Keskin Temelo?lu E, Y?ld?r?m ?im?ir I, ?z???k S, Demir L, Eren E, Tuna EB, Ayta? H, Onay H, Ak?nc? B. Diagn Interv Radiol. 2017 Nov-Dec;23(6):428-434. doi: 10.5152/dir.2017.17019. Dete... | PubMed ID 29044029 |
| Algul S, Ozdenk C, Ozcelik O. Biol Sport. 2017 Dec;34(4):339-344. doi: 10.5114/biolsport.2017.69821. Epub 2017 Sep 20. Variations in leptin, nesfatin-1 and irisin levels induced by aerobic exercise in young trained and untrained male subjects | PubMed ID 29472736 |
| He, S., Le, N.A., Frediani, J.K., Winterberg, P.D., Jin, R., Liverman, R.,..., & Vos, M.B. (2017). Cardiometabolic risks vary by weight status in pediatric kidney and liver transplant recipients: A cross-sectional, single-center study in the USA. ... | PubMed ID 28718192 |
| Acar, S., Paketçi, A., Küme, T., Tuhan, H., Gürsoy Çalan, Ö., Demir, K.,..., & Abacı, A. (2017). Serum galectin-1 levels are positively correlated with body fat and negatively with fasting glucose in obese children. Peptides, 95, 51-56. Advance on... | PubMed ID 28728946 |
| ??atl?? G, An??k A, K??me T, ??alan ??g, D??ndar Bn, B??ber E, Abac?? A. J Endocrinol Invest. 2015 Aug;38(8):909-13. Doi: 10.1007/S40618-015-0277-8. Epub 2015 Apr 2. Serum Nesfatin-1 And Leptin Levels In Non-Obese Girls With Premature Thelarche. | PubMed ID 25833360 |
| Liu L, Gu H, Zhao Y, An L, Yang J. Exp Ther Med. 2014 Dec;8(6):1813-1818. Epub 2014 Sep 30. Glypican 4 May Be Involved In The Adipose Tissue Redistribution In High-Fat Feeding C57Bl/6J Mice With Peroxisome Proliferators-Activated Receptor ?? Agoni... | PubMed ID 25371737 |
| Rasekhi H, Karandish M, Jalali Mt, Mohammadshahi M, Zarei M, Saki A, Shahbazian H. J Diabetes Metab Disord. 2015 Jan 14;14(1):1. Doi: 10.1186/S40200-014-0127-9. Ecollection 2015. Phylloquinone Supplementation Improves Glycemic Status Independent O... | PubMed ID 25654061 |
| Wu Cc, Weng Wl, Lai Wl, Tsai Hp, Liu Wh, Lee Mh, Tsai Yc. Evid Based Complement Alternat Med. 2015;2015:391767. Doi: 10.1155/2015/391767. Epub 2015 Feb 23. Effect Of Lactobacillus Plantarum Strain K21 On High-Fat Diet-Fed Obese Mice. | PubMed ID 25802537 |
| Karadag As, Ertugrul Dt, Kalkan G, Bilgili Sg, Celik Ht, Takci Z, Balahoroglu R, Calka O. Dermatology. 2013;227(2):103-8. Doi: 10.1159/000351769. Epub 2013 Sep 10. The Effect Of Acitretin Treatment On Insulin Resistance, Retinol-Binding Protein-4,... | PubMed ID 24021889 |
| Yao Y, Li Xb, Zhao W, Zeng Yy, Shen H, Xiang H, Xiao H. Lipids Health Dis. 2010 May 19;9:49. Doi: 10.1186/1476-511X-9-49. Anti-Obesity Effect Of An Isoflavone Fatty Acid Ester On Obese Mice Induced By High Fat Diet And Its Potential Mechanism. | PubMed ID 20482839 |
| Xie X, Yang S, Zou Y, Cheng S, Wang Y, Jiang Z, Xiao J, Wang Z, Liu Y. Brain Res. 2013 Jan 23;1491:147-55. Doi: 10.1016/J.Brainres.2012.11.007. Epub 2012 Nov 14. Influence Of The Core Circadian Gene "Clock" On Obesity And Leptin Resistance In Mice. | PubMed ID 23159716 |
| Hajihashemi P, Azadbakht L, Hashemipor M, Kelishadi R, Esmaillzadeh A. Mol Nutr Food Res. 2014 Jun;58(6):1301-8. Doi: 10.1002/Mnfr.201300582. Epub 2014 Jan 30. Whole-Grain Intake Favorably Affects Markers Of Systemic Inflammation In Obese Children... | PubMed ID 24478050 |
| Yang Y, Zhang X, Fu Y, Yang H. Toxicol Lett. 2014 Jun 16;227(3):172-8. Doi: 10.1016/J.Toxlet.2014.03.009. Epub 2014 Apr 4. Leptin And Il-8: Two Novel Cytokines Screened Out In Childhood Lead Exposure. | PubMed ID 24709140 |
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Questions and answers from customers related to EK0437 Human Leptin ELISA Kit PicoKine™
17 Related Questions
Question
We have acquired the products leptin (EK0437), adiponectin (EK0595) and endothelin (EK0945) from BOSTER and our sample type is humans' plasma (EDTA). We have read the respective datasheets. Even so, we need helping, since we have not conditions to test sample dilution proportion. What dilution ratio do you suggest for using with these kits? 1:10, 1:100, 1:1000 or another one? Please, give us numbers.
Verified Customer
Asked: 2020-02-28
Answer
Please see the following recommended dilution ratios for plasma (EDTA) from normal healthy human. leptin (EK0437), 1:20 adiponectin (EK0595) around 1:2000 endothelin (EK0945) 1:1
Boster Scientific Support
Answered: 2020-02-28
Question
Dear Technical Support: I am interested with Human Leptin ELISA Kit PicoKine for human population. My query is; how does these Human Leptin ELISA Kit PicoKine work well for urine sample in human adolescent? Is it required to concentrate the sample in order to measure the hormone?
Verified Customer
Asked: 2020-01-27
Answer
The product Human Leptin ELISA Kit PicoKine has not been tested particularly in human adolescents, however the typical human urine does not need to be concentrated and can be diluted using these Human Leptin ELISA Kit PicoKine if necessary.
Boster Scientific Support
Answered: 2020-01-27
Question
I want to purchase your Human Leptin ELISA Kit PicoKine, but I have some questions; does this kit would be useful in rabbit serum?
Verified Customer
Asked: 2019-08-15
Answer
The product Human Leptin ELISA Kit PicoKine have not been tested for any cross reactivity with rabbit samples, thus we do not know if the kit will work with rabbit serum samples. In this kit both capture and detection antibody are monoclonal so unless the homology between human and rabbit is very high, there would be a possibility that it will cross react, but we cannot guarantee.
Boster Scientific Support
Answered: 2019-08-15
Question
Please help with this. On page 6 of the attached insert...it states the dilution of sample must be made with the sample diluent. But it does not state the target dilutions to be prepared by the user. I looked through this on the attached insert but also cannot understand. Please clarify for me asap Sample Dilution The target protein concentration should be estimated and appropriate sample dilutions should be selected such that the final protein concentration lies near the middle of the linear dynamic range of the assay. It is recommended to prepare 150 ?l of sample for each replicate to be assayed. The samples should be diluted with sample diluent and mixed gently.
Verified Customer
Asked: 2019-06-07
Answer
Please see the following recommended dilution ratios for Human Leptin PicoKine
Boster Scientific Support
Answered: 2019-06-07
Question
EK0437 Human Leptin PicoKine ELISA Kit I have a customer who is interested in the kit. They want to test it with human serum samples. Please provide your QC data for the current lot of kit along with reference values for serum samples.
Verified Customer
Asked: 2015-05-19
Answer
COA
Boster Scientific Support
Answered: 2015-05-19
Question
Q: if the enzyme conjugated Leptin antibodies are mixed with the substrate, will that convert the substrate into the enzymatic reaction product? Or the enzyme function is only activated when the antibody is attached with the Leptin antigen?
R. Allen
Asked: 2019-12-05
Answer
A: The enzyme is always active. Avoid contaminating the substrate with enzyme prior to the incubation otherwise it compromises the assay with false positive signal.
Boster Scientific Support
Answered: 2019-12-05
Question
Q: how many samples can be assayed in a Picokine® ELISA Kit?
Verified Customer
Asked: 2019-10-11
Answer
A: The Picokine® ELISA Kits will generally run a 7-point standard curve, non-specific binding wells, and 39 samples in duplicate. this may vary slightly by kit so please refer to each datasheet for details.
Boster Scientific Support
Answered: 2019-10-11
Question
Q: What is the optimal O.D. value for Leptin ELISA kit? I used your Leptin ELISA on serum samples. For my positive control, I received an O.D. value of 0.826, while my negative control received a value of 0.136. I obtained both of these controls from the ELISA kit, where your kit's typical data shows O.D. values much higher than my positive control and your background is lower. My samples O.D. values are around 0.225 and the highest is only 0.357. can I consider these samples contain Leptin even though the O.D. values are not very high?
Verified Customer
Asked: 2019-06-20
Answer
A: The absolute O.D. values may change according to incubation time. The more you incubate the higher the O.D. values are going to be. an important assessment should be is whether your sample O.D. values are statistically significantly higher than your blank values. regarding your assay, you could extend your development time in the substrate incubation step to obtain higher O.D. values, as long as your negative controls' O.D. values are not increasing faster in relation to your positive controls. typically, a sample with O.D. value 2 standard deviations higher than your negative controls can be considered positive. We calculate the sensitivity of this ELISA kit by converting cutoff O.D. value, calculated as the average of 20 negative controls plus 2 standard deviations of the 20 negative controls, into a concentration. in other words, when we claim this Leptin ELISA kit to have sensitivity of 10pg/ml, that means the minimum amount of Leptin that can be declared/interpreted as positive by the above standard is 10pg/ml.
Boster Scientific Support
Answered: 2019-06-20
Question
Q: Can Leptin ELISA Kits be used with tissue homogenates (or other non-validated sample types)?
S. Garcia
Asked: 2019-05-29
Answer
A: Unfortunately, Boster Bio has not routinely validated tissue homogenates as a sample type for ELISA kits. This does not mean that ELISA kits are not suitable for other sample types than we have tested: it means further investigation is a must. One will need to perform a spike and recovery study to determine if an unvalidated sample type will work with a particular kit. To perform a spike and recovery experiment, one should divide a sample into two aliquots. In one of the aliquots, the user should spike in a known amount of the kit standard. a dilution series is performed comparing the spiked versus the unspiked sample. Generally, samples with expected recovery and linearity between 80-120% are considered acceptable. This method can be used to validate any sample type that has not been evaluated by Boster Bio. for a more detailed spike and recovery protocol, please contact technical support.
Note: acceptable ranges should be determined individually by each laboratory. Additionally, technical support can help determine if a buffer component is not compatible with a given ELISA kit. please see the Citations tab on the product webpage for peer-reviewed papers utilizing a wide range of sample types. We also have an innovator's reward program where if the user validates our ELISA kits in applications or samples previously not validated by Boster Bio or other users, and share such information with us by submit a review, we will reward the user's efforts with a free antibody or ELISA kit from our catalog. Biocompare.com will also give $20 Amazon giftcard as an additional reward, if the review is submitted there as well.
Boster Scientific Support
Answered: 2019-05-29
Question
Q: what is the protocol regarding preparation of cell lysates prepared for use in Picokine® ELISA kits?
Verified Customer
Asked: 2019-01-14
Answer
A: for those Picokine® ELISAs where cell or tissue lysate is a validated sample type, sample preparation instructions for lysate are present in the product insert. Components in lysate and lysis buffer can change immunoreactivity, so if lysate is not a validated sample type, care must be taken in sample preparation and validation.
Boster Scientific Support
Answered: 2019-01-14
Question
Q: how long can samples (cell cultures, serum, and plasma) be stored and still be stable for analysis Leptin using the EK0437 Human Leptin Picokine® ELISA Kit?
D. Varadkar
Asked: 2018-09-19
Answer
A: Boster Bio does not evaluate sample stability. Variations in sample collection, processing, and storage may change the stabilityof samples. It is recommend to assay sample right after collection when possible, or aliquot into single use volumes and store samples frozen. avoid repetitive freeze-thaw cycles with the stored samples to prevent protein degradation.
Boster Scientific Support
Answered: 2018-09-19
Question
Q: can I use citrate plasma as samples in Human Leptin Picokine® ELISA Kit (Catalog # EK0437)?
Verified Customer
Asked: 2018-04-16
Answer
A: Chelating agents such as EDTA, Heparin and Citrate can attach metal ions from the functional domain of Leptin causing degradation of its protein structure. Leptin may be denatured as a result and may compromise the assay's measurements. The chilating sites could also be too close to the epitopes a must for detection and block the antigen antibody reaction. We have tested the Leptin ELISA, treating samples with various anticoagulants and decided that heparin or EDTA can be used for treatment of blood/plasma samples. Do not use other anticoagulents when collecting samples.
Boster Scientific Support
Answered: 2018-04-16
Question
Q: which procedure should I follow in order to thaw whole blood sample for Leptin ELISA after freezing?
Verified Customer
Asked: 2016-06-17
Answer
A: do not freeze and thaw whole blood. erythrocytes are fragile and, if frozen and thawed, will undergo hemolysis rendering the samples useless. To keep your blood samples to test Leptin for a later time, you should let the blood clot in glass tubes and separate the serum to freeze for later analysis.
Boster Scientific Support
Answered: 2016-06-17
Question
Do you have any information available documenting the effects of aprotinin on the ELISA results using EK0437?
Asked: 2020-12-01
Answer
Our lab hasn't validated effects of aprotinin on the ELISA results using the Human Leptin ELISA Kit PicoKine™ (EK0437). Please run a pilot test to see if it has any effect.
Boster Scientific Support
Answered: 2020-12-01
Question
What is the suggested dilution ratio for cell culture supernates using the Human Leptin ELISA Kit PicoKine™ (EK0437)?
Asked: 2019-09-19
Answer
For cell culture supernates, concentrations of the samples can vary greatly. We suggest to run pilot tests for different group samples to figure out the optimal dilution ratio. Our lab tested unstimulated human peripheral blood mononuclear cells with a dilution of 1:1 and didn't detect any measurable value.
Boster Scientific Support
Answered: 2019-09-20
Question
What is the suggested dilution ratio for cell lysates using the Human Leptin ELISA Kit PicoKine™ (EK0437)?
Asked: 2019-09-19
Answer
For cell lysates, concentrations of the samples can vary greatly. We suggest to run pilot tests for different group samples to figure out the optimal dilution ratio. Our lab tested unstimulated human peripheral blood mononuclear cells with a dilution of 1:1 and didn't detect any measurable value.
Boster Scientific Support
Answered: 2019-09-20
Question
What is the suggested dilution ratio for serum and plasma (heparin, EDTA) using the Human Leptin ELISA Kit PicoKine™ (EK0437)?
Asked: 2019-09-19
Answer
For serum and plasma (heparin, EDTA), the suggested dilution ratio from normal healthy human is 1:20.
Boster Scientific Support
Answered: 2019-09-20
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