Long-form research.
Mechanism · administration · safety.

Muscle growth peptide research focuses on compounds that stimulate the body\'s own muscle-building pathways — particularly the IGF-1/mTOR signalling axis and satellite cell activation. IGF-1 LR3 is a long-acting form of Insulin-like Growth Factor 1, a hormone naturally produced in the liver that drives muscle protein synthesis and satellite cell (muscle stem cell) proliferation. TB-500, also studied in the healing category, contributes here through its role in directing satellite cells to repair sites and improving blood supply to muscle tissue. These peptides are studied by researchers interested in skeletal muscle biology, hypertrophy mechanisms, and post-injury muscle recovery.

Weight loss peptide research centres on compounds that either directly break down fat cells or stimulate the body\'s own growth hormone — which drives fat burning, lean mass preservation, and metabolic health. AOD-9604 is an engineered fragment of human growth hormone designed specifically to activate fat-cell breakdown (lipolysis) without the blood sugar dysregulation or anabolic side-effects of full-length HGH. CJC-1295 and Ipamorelin are studied in combination: CJC-1295 signals the pituitary gland to produce more growth hormone, while Ipamorelin amplifies the resulting pulse — producing up to 5× more GH than either compound alone, with a highly selective profile that avoids the cortisol and prolactin increases seen with older GH-releasing peptides. Together, these compounds represent a sophisticated approach to metabolic research that goes well beyond simple calorie restriction. A separate, pharmaceutical class — the incretin analogues semaglutide, tirzepatide and retatrutide and the amylin analogue cagrilintide — acts on GLP-1, GIP, glucagon and amylin receptors; semaglutide and tirzepatide are approved prescription medicines, while research-labelled vials of any of the four are unapproved products outside that regulated supply chain.

Sleep quality is increasingly recognised as one of the most powerful levers for health, cognitive performance, and longevity. DSIP (Delta Sleep-Inducing Peptide) was discovered in 1977 when researchers isolated it from rabbit blood during natural sleep and found that injecting it into alert rabbits induced slow-wave (deep) sleep within 30 minutes. Unlike sleeping pills, which work by broadly suppressing brain activity, DSIP specifically promotes delta-wave (slow-wave) sleep — the deepest and most restorative stage — without sedation, respiratory depression, or dependence. Selank contributes to this category through its anxiolytic mechanism: by reducing the hyperarousal (racing thoughts, elevated cortisol, difficulty switching off) that underlies stress-induced insomnia, without the muscle-relaxing or respiratory effects of benzodiazepines.

PT-141, known clinically as Bremelanotide and sold as Vyleesi®, is the only FDA-approved peptide specifically for sexual dysfunction — approved in 2019 for hypoactive sexual desire disorder in premenopausal women. What makes PT-141 unique is where it acts: not in the blood vessels, like Viagra or Cialis, but in the brain. It activates melanocortin receptors in the hypothalamus — a region involved in desire, arousal, and motivation — producing an increase in sexual interest that is centrally driven rather than mechanically facilitated. This makes it relevant for addressing the desire and psychological components of sexual dysfunction, which PDE5 inhibitors cannot reach. It has been studied in both men and women, giving it one of the broadest clinical research bases of any peptide on this site.

PeptideGuide rates vendors on 5 weighted axes: Testing (30%), Purity (20%), Regional-Friendliness (15%), Value (15%), Trust (20%). Each axis has a publishable rubric. The composite score 0-10 produces regional leaderboards and Editor\'s Choice designations. The personalized finder applies axis multipliers per buyer-priority answer. Methodology is transparent and quarterly-reviewed. Affiliate commissions do NOT affect scoring.

A genuine CoA names the lab, the batch (lot number), the test methods used, and is signed/dated. Demand HPLC (purity %) AND LC-MS (identity confirmation via molecular mass) at minimum — without both, purity alone tells you nothing about WHAT is pure. CLND verifies absolute peptide content; LAL measures endotoxin (critical for injection research); FTIR confirms structural identity. Independent third-party lab CoAs (Janoshik Analytical, Eurofins, etc.) beat in-house CoAs. Per-batch CoA archive beats a single demo CoA. Apply the 8-item red flag checklist before ordering.

RUO ("research use only") is a regulatory positioning device. It places vendors outside pharmaceutical drug regulation and inside research-reagent regulation. It permits sale, advertising (restricted), shipping, and purchase for laboratory research. It does NOT permit therapeutic claims, dosing recommendations for human use, or sale to known therapeutic-use customers. It does NOT certify quality. It does NOT transfer legal use-protection to buyers. Regulatory treatment varies meaningfully across US (FDA), EU (EMA + national agencies), UK (MHRA), AU (TGA Schedule 4 — strictest), JP (PMD Act + import confirmation above personal-use limits), CA (Health Canada NPN/DIN exemption), GCC (SFDA/MoHAP/KFDA/NHRA), Africa (per-country: SAHPRA/NAFDAC/EDA/etc.), LATAM (ANVISA/COFEPRIS/ANMAT/INVIMA/ISP/DIGEMID), and Russia (Roszdravnadzor + sanctions overlay).

Reconstitution math: concentration (mg/mL) = peptide mass (mg) / volume added (mL). Common reconstitutions: 5mg vial + 1mL BAC water = 5mg/mL; 5mg + 2mL = 2.5mg/mL; 5mg + 2.5mL = 2mg/mL. Use bacteriostatic water (BAC water), insulin syringes, refrigerator storage 28-day window for reconstituted vials, refrigerator or freezer for lyophilized vials pre-reconstitution. Lyophilized peptides do NOT require cold-chain shipping — room-temperature international transit is operationally clean. Avoid tap water, distilled water for multi-day use, shaking during reconstitution, and high reconstitution temperatures.

4-stage supply chain: Synthesis (mostly Chinese manufacturers, some Slovakia/Cyprus/Spain/Vietnam) → Bulk purchase (vendors buy kilogram-scale) → Repackaging + CoA verification (where consumer-facing vendor differentiation actually happens) → Warehouse + shipping + customer service. Quality lives at stages 1-3, not stage 4. Most consumer vendors buy from the same upstream manufacturers — differentiation comes from testing depth, batch-level verification, and operating history. Particle Peptides (Slovakia) is the EU gold standard via vertical integration. Core Peptides (US) is the US gold standard via multi-lab third-party CoA verification compensating for non-vertical-integration. Weighting testing depth heavily is the buyer\'s rational response to the supply-chain structure.

WADA Prohibited List applies to tested athletes registered with WADA-Code-adopting federations (Olympic pathway, NCAA, World Athletics, FIFA, national teams in most sports). Most research peptides are banned: BPC-157 (S0 since 2022), TB-500 (S2.3), IGF-1 LR3 (S2.3), CJC-1295/Ipamorelin (S2.2.4), MGF (S2.3), AOD-9604 (S2.2.3), GHK-Cu injectable (S0). Strict liability — "I didn\'t know" is not a defense. First-violation bans run up to four years: two by default for S0 substances, four for S2. TUE structurally closed for research-grade compounds. Detection windows 2-10 weeks depending on compound. Out-of-competition testing means no "wash out" strategy is safe. Non-tested athletes (recreational, masters in non-WADA federations) face NO WADA enforcement.

Семакс и Селанк — российские разработки с одобрением как лекарства в России. Доступны через аптеки с рецептом. Это отличает российский рынок от западного, где они research-use-only. Отпускаются по рецепту; PeptideGuide не рекомендует обходить рецептурный порядок.

BPC-157 и TB-500 — наиболее изученные заживляющие пептиды. NPCRIZ биорегуляторы Хавинсона — уникальная российская традиция тканеспецифичных пептидов. Запрещены WADA. Биорегуляторы НПЦРИЗ доступны внутри России (Peptide.ru, распространители НПЦРИЗ); BPC-157 и TB-500 — только у международных vendors.

Эпиталон — российская научная традиция Хавинсона с опубликованной клинической литературой. NPCRIZ биорегуляторы — уникальная российская традиция геронтологических пептидов. GHK-Cu — модуляция гена. Все под WADA S0.

Тимоген, Тималин — российские разработки одобрены как лекарства в России. NPCRIZ биорегуляторы тимуса — уникальная русская традиция. Это отличает российский рынок от западного, где LL-37 и lactoferrin фрагменты — research-use-only.

НПЦРИЗ биорегуляторы — уникальная российская научная традиция короткоцепочечных тканеспецифичных пептидов. Эпиталон (эпифиз) наиболее изучен. Классифицированы как БАДы — доступны без рецепта. Доступны через НПЦРИЗ или PeptideProduct EU. WADA-статус нечеткий.

Покупка пептидов в России: биорегуляторы Хавинсона продаются внутри страны (Peptide.ru, НПЦРИЗ); исследовательские пептиды — у международных vendors, что требует криптовалюты. Российская таможня обычно пропускает декларации research-use-only за 7-14 дней. НПЦРИЗ биорегуляторы — уникальная русская научная традиция через Хавинсон-распространителей.

QSC Peptides RU — Editor's Choice России 2026: сторонняя верификация Janoshik и самые низкие цены; оплата криптовалютой. Peptide.ru указан вне рейтинга как магазин биорегуляторов Хавинсона. НПЦРИЗ биорегуляторы — уникальная российская научная традиция через отдельный канал.

Peptide.ru — официальный магазин биорегуляторов Хавинсона (цитогены, лингвалы, Revilab), а не поставщик исследовательских пептидов: ни одного из 16 отслеживаемых соединений в каталоге нет, сертификатов анализа ВЭЖХ/МС нет. Указан вне рейтинга (4.5/10). Editor's Choice России — QSC Peptides RU.

SwissChems — нишевый американский поставщик для российского рынка. HPLC + LC-MS, чистота 99.3%. Доставка через посредников или криптовалюта (USDT/Tron). После санкций 2022 покупка дороже и медленнее; Editor's Choice для России — QSC Peptides RU.