| Kitsize | 12x8 |
| Method | ELISA |
| Incubationtime | 1x1h;1x30min |
| Standardrange | 0.37-30ng/mL |
| Specimen/Volumes | 20µLSerum |
| Substrate/isotope | TMB450nm |
| RegulatoryStatus: | EU:CE |
TheLC-MS/MSisourbenchmark
Dehydroepiandrosterone(DHEA)anditssulfateesterDHEA-Sarethemostabundantsexsteroidhormonesinhumans,providingalargeprecursorreservoirforthesynthesisofandrogensandestrogens.However,onlythenon-sulfated(free)DHEAshowsBIOLOGicalactivity.
IBLInternationaloffersahighlyspecificELISAfordeterminingserumDHEAlevels,whichwascalibratedagainstthereferencemethodLC-MS/MS.Theassay"sdistinguishingfeaturesare:
- ExceptionalconcordancetoLC-MS/MS:
IBLDHEAELISA=0.94xLC-MS/MS+0.13;r²=0.99;N=50 - Verygoodconcordancetothegoldstandard
ImmunotechRIA*):
IBLDHEAELISA=0.83xImmunotechRIA–0.37;r²=0.96;N=48
*)RIAwithextraction - Extraction-freeassay
- Adaptabletoopen-systemELISAanalyzers
- 2kitcontrols
MeasurementofserumDHEAisausefulMarkerofadrenalandrogensynthesis.Decreasedlevelsmayindicateadrenalinsufficiency.Elevatedlevelsarefoundinvariousdiseases,includingadrenalcorticalcarcinoma,tumorswithectopicACTHproduction,adrenalhirsutism,congenitaladrenalhyperplasia,andCushing"sdisease(pituitaryCushing"ssyndrome).
Moreover,ourDHEAELISA(RE52221)showsanexcellentagreementwiththegoldstandardassayRIAbyImmunotech. GeneralInformation Enzymeimmunoassayforthein-vitro-diagnosticquantitativedeterminationofDHEAinhumanserum.Dehydroepiandrosterone(DHEA;androstenolone;3ß-hydroxy-5-androsten-17-one)isaC19steroidproducedintheadrenalcortexand,toalesserextent,gonads.DHEAservesasaprecursorintestosteroneandestrogensynthesis.Duetothepresenceofa17-oxo(ratherthanhydroxyl)group,DHEAhasrelativelyweakandrogenicactivity,whichhasbeenestimatedat~10%thatoftestosterone.Howeverinneonates,peripubertalchildrenandinadultwomen,circulatingDHEAlevelsmaybeseveral-foldhigherthantestosteroneconcentrations,andrapidperipheraltissueconversiontomorepotentandrogens(androstenedioneandtestosterone)andestrogensmayoccur.Moreover,DHEAhasrelativelylowaffinityforsex-hormonebindingglobulin.ThesefactorsmayenhancethephysiologicbiopotencyofDHEA.ThephysiologicroleofDHEAhasnotbeenconclusivelydefined.Avarietyofinvitroeffects,includingantiproliferativeeffectsindifferentcelllinesandeffectsonenzyme-mediatedcellmetabolism,havebeenreported.InvivostudiessuggestthatDHEAmayaffectcholesterolandlipidmetabolism,insulinsensitivityandsecretionandimmunefunction.AbnormalDHEAlevelshavebeenreportedinschizophreniaandobesity.TherapeuticadmiNISTrationofDHEAhasbeenproposedforseveralconditions,includingobesityandcardiovasculardisease.SerumDHEAlevelsarerelativelyhighinthefetusandneonate,lowduringchildhood,andincreaseduringpuberty.IncreasedlevelsofDHEAduringadrenarchemaycontributetothedevelopmentofsecondarysexualhair.SerumDHEAlevelsprogressivelydeclineafterthethirddecadeoflife.NoconsistentchangesinserumDHEAlevelsoccurduringthemenstrualcycleorpregnancy;however,paritymaylowerserumDHEAlevelsinpremenopausalwomen.DHEAhasarapidmetabolicclearancerateascomparedtoitssulfatedconjugate,DHEA-S.Becauseofthis,serumDHEAlevelsare100-1000foldlowerthanDHEA-Slevels.SerumDHEAlevelsincreaseinresponsetoexogenousACTHadministration.MeasurementofserumDHEAisausefulmarkerofadrenalandrogensynthesis.Abnormallylowlevelsmayoccurinhypoadrenalism,andelevatedlevelsoccurinseveralconditions;includingvirilizingadrenaladenomaandcarcinoma,21-hydroxylaseand3ß-hydroxysteroiddehydrogenasedeficienciesandinsomecasesoffemalehirsutism.SinceverylittleDHEAisproducedbythegonads,measurementofDHEAlevelsmayaidinthelocalizationofandrogensourceinvirilizingconditions.

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1. 直接法测定抗原 2.间接法测定抗体 3.双抗体夹心法测定抗原4. 竞争法测定抗原 厚百生物专业提供各类生化实验试剂、仪器、耗材,提供技术服务,满足您的实验室常规采购需求。厚百,让您更省心!
(1) 包被:用0.05M PH9.牰碳酸盐包被缓冲液将抗体稀释至蛋白质含量为1~10μg/ml。在每个聚苯乙烯板的反应孔中加0.1ml,4℃过夜。次日,弃去孔内溶液,用洗涤缓冲液洗3次,每次3分钟。(简称洗涤,下同)。
(2) 加样:加一定稀释的待检样品0.1ml于上述已包被之反应孔中,置37℃孵育1小时。然后洗涤。(同时做空白孔,阴性对照孔及阳性对照孔)。
(3) 加酶标抗体:于各反应孔中,加入新鲜稀释的酶标抗体(经滴定后的稀释度)0.1ml。37℃孵育0.5~1小时,洗涤。
(4) 加底物液显色:于各反应孔中加入临时配制的TMB底物溶液0.1ml,37℃10~30分钟。
(5) 终止反应:于各反应孔中加入2M硫酸0.05ml。
(6) 结果判定:可于白色背景上,直接用肉眼观察结果:反应孔内颜色越深,阳性程度越强,阴性反应为无色或极浅,依据所呈颜色的深浅,以“+”、“-”号表示。也可测O·D值:在ELISA检测仪上,于450nm(若以ABTS显色,则410nm)处,以空白对照孔调零后测各孔O·D值,若大于规定的阴性对照OD值的2.1倍,即为阳性。
间接法:
用包被缓冲液将已知抗原稀释至1~10μg/ml,每孔加0.1ml,4℃过夜。次日洗涤3次。加一定稀释的待检样品(未知抗体)0.1ml于上述已包被之反应孔中,置37℃孵育1小时,洗涤。(同时做空白、阴性及阳性孔对照)于反应孔中,加入新鲜稀释的酶标第二抗体(抗抗体)0.1ml,37℃孵育30-60分钟,洗涤,最后一遍用DDW洗涤。其余步骤同“双抗体夹心法”的4、5、6。
表面抗体是双抗原夹心法
E抗体和核心抗体是竞争抑制法或间接法
1. 包被:用0.05M PH9,碳酸盐包被缓冲液将抗体稀释至蛋白质含量为1~10μg/ml,在每个聚苯乙烯板的反应孔中加0.1ml,4℃过夜。次日,弃去孔内溶液,用洗涤缓冲液洗3次,每次3分钟。
2. 加样:加一定稀释的待检样品0.1ml于上述已包被之反应孔中,置37℃孵育1小时。然后洗涤。(同时做空白孔,阴性对照孔及阳性对照孔)。
3. 加酶标抗体:于各反应孔中,加入新鲜稀释的酶标抗体(经滴定后的稀释度)0.1ml,37℃孵育0.5~1小时,洗涤。
4. 加底物液显色:于各反应孔中加入临时配制的TMB底物溶液0.1ml,37℃10~30分钟。
5. 终止反应:于各反应孔中加入2M硫酸0.05ml。
6. 结果判定:可于白色背景上,直接用肉眼观察结果:反应孔内颜色越深,阳性程度越强,阴性反应为无色或极浅,依据所呈颜色的深浅,以“+”、“-”号表示。也可测OD值:在ELISA检测仪上,于450nm(若以ABTS显色,则410nm)处,以空白对照孔调零后测各孔OD值,若大于规定的阴性对照OD值的2.1倍,即为阳性。
方法二:用于检测未知抗体的间接法:
用包被缓冲液将已知抗原稀释至1~10μg/ml,每孔加0.1ml,4℃过夜。次日洗涤3次。加一定稀释的待检样品(未知抗体)0.1ml于上述已包被之反应孔中,置37℃孵育1小时,洗涤。(同时做空白、阴性及阳性孔对照)于反应孔中,加入新鲜稀释的酶标第二抗体(抗抗体)0.1ml,37℃孵育30~60分钟,洗涤,最后一遍用DDW洗涤。其余步骤同“双抗体夹心法”的4、5、6。

