{"product_id":"p21","title":"P21","description":"\u003cdiv class=\"ds-virtual-list-items _6f2c522\"\u003e\n\u003cdiv class=\"ds-virtual-list-visible-items\"\u003e\n\u003cdiv class=\"_4f9bf79 d7dc56a8 _43c05b5\"\u003e\n\u003cdiv class=\"ds-message _63c77b1\"\u003e\n\u003cdiv class=\"ds-markdown ds-assistant-message-main-content\"\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003e\u003ca href=\"https:\/\/corepeptides.in\/\"\u003eCorePeptides India\u003c\/a\u003e supplies P21-research identifier P021-as a sterile, lyophilized powder, 5 mg per nitrogen‑flushed vial. Every batch arrives with a fully traceable Certificate of Analysis covering HPLC purity, mass identity, and residual solvent profile.\u003c\/span\u003e\u003c\/p\u003e\n\u003ch3\u003e\u003cspan class=\"\"\u003eProduct Specifications\u003c\/span\u003e\u003c\/h3\u003e\n\u003cdiv class=\"ds-scroll-area ds-scroll-area--show-on-focus-within ds-scroll-area--enabled _1210dd7 c03cafe9\"\u003e\n\u003ctable\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003e\u003cspan class=\"\"\u003eSpecification\u003c\/span\u003e\u003c\/th\u003e\n\u003cth\u003e\u003cspan class=\"\"\u003eDetail\u003c\/span\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eProduct Class \/ Category\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eNeurogenic Tetradecapeptide (CNTF-Derived Fragment)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eResearch Identifier \/ Sequence\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eP021 (P21); Ac‑Val‑Gly‑Asp‑Gly‑Gly‑Leu‑Phe‑Glu‑Lys‑Lys‑Leu‑NH₂\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eSupplier \/ Brand\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eCorePeptides India\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eHPLC Purity Threshold\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003e\u0026gt;99% (RP‑HPLC, C18, 214 nm, batch‑specific)\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eTarget Receptors \/ Chemical Pathways\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eCNTF receptor complex (CNTFRα‑gp130‑LIFRβ) — partial in‑vitro binding; downstream upregulation of BDNF expression and inhibition of GSK‑3β‑mediated tau phosphorylation observed in primary neuronal cultures\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eRegulatory Status\u003c\/span\u003e\u003c\/td\u003e\n\u003ctd\u003e\u003cspan class=\"\"\u003eFor In‑Vitro \u0026amp; Laboratory Analytical Research Only. Not for human, veterinary, diagnostic, or therapeutic use.\u003c\/span\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003chr\u003e\n\u003ch2\u003e\u003cspan class=\"\"\u003eResearch Overview \u0026amp; Mechanism of Action\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eP21 is an acetylated, C‑terminally amidated 11‑mer peptide modelled on residues 147–157 of human ciliary neurotrophic factor. Two substitutions - Asp for Glu at position 3 and Glu for Gln at position 9-were introduced to improve solution stability. The monoisotopic mass is 1176.3 Da. HPLC chromatograms in our laboratory show a single sharp peak; the COA you receive reflects that exact analysis, not a generic lot average.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eThis peptide does not simply mimic full‑length CNTF. In vitro data point to a biased interaction with the CNTF receptor complex that triggers BDNF transcription without inducing the full JAK\/STAT cascade normally seen with CNTF. That makes it a valuable tool for dissecting neurotrophin‑mediated signalling. Researchers use P21 in hippocampal progenitor‑cell differentiation assays, primary cortical‑neuron cultures, and tau‑hyperphosphorylation models. Receptor selectivity is molar‑ratio dependent, so every experiment demands precise analytical concentration control. The lyophilized cake may show minor cracks — a natural consequence of freeze‑drying that leaves molecular integrity untouched.\u003c\/span\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003e\u003cspan class=\"\"\u003eHandling, Reconstitution \u0026amp; Storage Protocol\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eStore the unopened vial at –20 °C. Transport at ambient temperature for 3–4 days causes no detectable loss of purity. After shipping, let the vial sit on the bench for 15–20 minutes before opening; this prevents condensation from pulling moisture into the peptide matrix.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eReconstitution for analytical research:\u003c\/span\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eUse sterile bacteriostatic water (0.9% benzyl alcohol) or sterile PBS, pH 7.4.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eTarget a stock analytical concentration of 1 mg\/mL. Incline the vial and introduce the diluent slowly down the glass.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eSwirl gently-never vortex. The acetylated N‑terminus and amidated C‑terminus make the peptide reasonably soluble, but mechanical stress shears the backbone.\u003c\/span\u003e\u003c\/li\u003e\n\u003cli class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eFor low‑micromolar working solutions in cell‑culture plates, include 0.1% molecular‑biology‑grade BSA as a carrier protein. Polystyrene adsorption can sequester measurable peptide mass and shift the effective molar ratio.\u003c\/span\u003e\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cspan class=\"\"\u003eOnce reconstituted, keep the solution at 2–8 °C and use within 2‑3 weeks. Single‑use aliquots are strongly recommended. A single freeze‑thaw cycle can reduce detectable signal in ELISA‑based BDNF readouts by roughly 10–15%. Plan your aliquot volumes accordingly.\u003c\/span\u003e\u003c\/p\u003e\n\u003chr\u003e\n\u003ch2\u003e\u003cspan class=\"\"\u003eScientific References \u0026amp; External Citations\u003c\/span\u003e\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003ca href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/?term=P021+peptide+neurogenesis\" rel=\"noreferrer\" target=\"_blank\"\u003e\u003cspan class=\"\"\u003ePubMed: P021 Neurogenic Peptide Research\u003c\/span\u003e\u003c\/a\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003e— Peer‑reviewed studies exploring BDNF upregulation, tau phosphorylation inhibition, and neurogenesis in in‑vitro and transgenic Alzheimer’s models.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003ca href=\"https:\/\/clinicaltrials.gov\/search?term=P021\" rel=\"noreferrer\" target=\"_blank\"\u003e\u003cspan class=\"\"\u003eClinicalTrials.gov: P021 Investigator‑Led Studies\u003c\/span\u003e\u003c\/a\u003e\u003cspan class=\"\"\u003e\u003cspan\u003e \u003c\/span\u003e— Registered clinical research protocols involving the P021 peptide fragment.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003chr\u003e\n\u003ch2\u003e\u003cspan class=\"\"\u003eFrequently Asked Research Questions\u003c\/span\u003e\u003c\/h2\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eWhat is the exact sequence and molecular weight of the P21 peptide?\u003c\/span\u003e\u003c\/strong\u003e\u003cbr\u003e\u003cspan class=\"\"\u003eThe research peptide supplied by CorePeptides India is P021, sequence Ac‑Val‑Gly‑Asp‑Gly‑Gly‑Leu‑Phe‑Glu‑Lys‑Lys‑Leu‑NH₂. The acetylated, amidated, single‑oxidation form has a monoisotopic mass of 1176.3 Da. This identity is confirmed by ESI‑MS on every batch‑specific Certificate of Analysis.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eHow should P21 be reconstituted for primary neuron experiments?\u003c\/span\u003e\u003c\/strong\u003e\u003cbr\u003e\u003cspan class=\"\"\u003ePrepare a 1 mg\/mL stock in sterile PBS or bacteriostatic water. Add 0.1% BSA when diluting to final working concentrations below 10 µM to minimise adsorptive loss to plasticware. Always allow the lyophilized cake to reach room temperature before adding the diluent to prevent moisture condensation.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eIs a batch‑matched Certificate of Analysis provided with every order?\u003c\/span\u003e\u003c\/strong\u003e\u003cbr\u003e\u003cspan class=\"\"\u003eYes. Every 5 mg vial from CorePeptides India ships with a printed and digitally archived COA showing the HPLC purity, retention time, ESI‑MS spectrum, and observed mass. The lot number on the vial links one‑to‑one with that COA.\u003c\/span\u003e\u003c\/p\u003e\n\u003cp class=\"ds-markdown-paragraph\"\u003e\u003cstrong\u003e\u003cspan class=\"\"\u003eCan this peptide be used in human clinical diagnostics or therapeutic development?\u003c\/span\u003e\u003c\/strong\u003e\u003cbr\u003e\u003cspan class=\"\"\u003eNo. P21 is manufactured strictly for in‑vitro laboratory research. It is not authorised for human or veterinary administration, diagnostic procedures, or therapeutic use. All orders are verified against this research‑only restriction.\u003c\/span\u003e\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e","brand":"Core Supplements","offers":[{"title":"Default Title","offer_id":44198427852859,"sku":null,"price":8999.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0696\/6411\/2699\/files\/ChatGPTImageAug1_2026_06_02_06PM.png?v=1789453669","url":"https:\/\/peptidesinindia.org\/products\/p21","provider":"Buy Peptides In India","version":"1.0","type":"link"}