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Semax �š„储存、稳定性与分析 — Questions and Answers

By Editorial Desk · published 2026-05-24 · last reviewed 2026-07-15 · Topic

ACTH(4-10) comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.

Last reviewed on 2026-07-15. Where a claim depends on a specific study, the study is described rather than over-claimed.

Semax 的储存、稳定性与分析

多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下,同时避免光照与反复升温。短期运输有时采用冷藏条件,但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数,以降低吸湿和微生物污染的风险。开封后若未一次用完,建议在干燥环境中密封并尽快放回低温储存。

溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集,其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸,因此氧化风险相对突出。工作液一般主张现配现用,或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率,而关于最佳条件的公开数据并不统一。

Semax Peptide Structure and Origin

The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.

Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.

Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.

Semax at a glance

PropertyValueNotes
外观白色至类白色粉末常见于冻干制剂
溶解度易溶于水在极性溶剂中一般也可溶
建议储存温度-20 °C冻干粉,避光密封
常见分析手段反相高效液相色谱常与质谱联用
主要降解路径水解与氧化溶液状态更显著

化学性质与分析表征

从分子层面看,Semax 是线性七肽,没有二硫键、糖基或脂链修饰,N 端为游离氨基,C 端为游离羧基。分子含组氨酸与谷氨酸侧链,因此在水和甲醇等极性溶剂中溶解良好,在非极性溶剂中溶解有限。计算分子量约为 814 Da,与其质子化离子的质荷比吻合,可用于质谱确认。

稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定,遇到强碱或长时间高温则明显断裂;甲硫氨酸侧链容易被氧化成亚砜,使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间,配制后的水溶液通常需要冷藏并尽快用完。

纯度评估以反相高效液相色谱为主,通过主峰面积百分比给出粗略结果,再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例,手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告,独立第三方检测常被用来核实标称值。

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Semax Structure and Research Background

Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.

Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.

Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.

Mechanism and Research

Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.

Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.

Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.

Semax Background and Chemistry

Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.

The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.

Reference notes

Delta cells (δ-cells or D cells) are somatostatin-producing cells. They can be found in the stomach, intestine and the pancreatic islets. Delta cells comprise ca 5% of the cells in the islets but may interact with many more islet cells than suggested by their low numbers. In rodents, delta-cells are located in the periphery of the islets; in humans the islet architecture is generally less organized and delta-cells are frequently observed inside the islets as well. In both species, the peptide hormone Urocortin III (Ucn3) is a major local signal that is released from beta cells (and alpha cells in primates) to induce the local secretion of somatostatin. It has also been suggested that somatostatin may be implicated in insulin-induced hypoglycaemia through a mechanism involving SGLT-2 receptors. Ghrelin can also strongly stimulate somatostatin secretion, thus indirectly inhibiting insulin release. Viewed under an electron microscope, delta-cells can be identified as cells with smaller and slightly more compact granules than beta cells. The δ-cells in the stomach contain CCKBR (which respond to gastrin) and M3 receptors (which respond to Ach). Respectively, these receptors will increase somatostatin output and decrease somatostatin output from the δ-cells. VIP, vasoactive intestinal peptide, acts positively on δ-cells resulting in more somatostatin being released.

Paul Bottomley is an American, English and Australian medical physicist. He pioneered the development of magnetic resonance imaging (MRI) that lead to modern commercial clinical 1.5 tesla MRI scanners, along with methods for performing noninvasive localized magnetic resonance spectroscopy (MRS) and applying them to the study of energy supply in human heart disease. In 2022 he retired as Russell H. Morgan Professor of Radiology and Director of the Division of MR Research at Johns Hopkins University where he is currently Professor Emeritus. He has about 200 peer-reviewed journal articles, over 50 U.S patents in MRI, MRS, and MRI-safe implantable lead technologies. He was a Founder and past member of the Board of Directors of SurgiVision Inc, a 1998 Johns Hopkins University start-up company which became MRI Interventions Inc, and is currently known as ClearPoint Neuro Inc.

=== Irritable bowel syndrome === There is evidence that a dietician-supervised low-FODMAP diet is the best available way to control IBS symptoms, though there is a lack of evidence on possible adverse effects. The beneficial effect of low-FODMAP for people with IBS may be related to reduced osmotic load in the gut or changes in gut-brain axis signaling. The low-FODMAP diet does not cause any significant change in the gut microbiota in people with IBS. The effectiveness of low-FODMAP diet in children with IBS is unclear. While restrictive diets like the low-FODMAP diet can help manage symptoms in patients with Irritable bowel syndrome, they pose a significant danger: they can increase the patient's risk of developing disordered eating. The initial success in symptom reduction may become a dangerous obsession with controlling food, potentially leading to conditions such as ARFID or Orthorexia nervosa. These issues severely impact clinical outcomes and quality of life, and worsen overall health. Early monitoring and intervention are crucial to catching and addressing these pathological eating patterns.

PFOA and PFOS are extremely persistent in the environment and resistant to typical environmental degradation processes. [They] are widely distributed across the higher trophic levels and are found in soil, air and groundwater at sites across the United States. The toxicity, mobility and bioaccumulation potential of PFOS and PFOA pose potential adverse effects for the environment and human health. In 2024 EPA published drinking water regulations for PFOA and five other PFAS.

Sources: en.wikipedia.org

Notes from published material

== Benefits == The coupling of POCT devices and electronic medical records enable test results to be shared instantly with care providers. The use of mobile devices in the health care setting also enable the health care provider to quickly access patient test results sent from a POCT device. A reduction in morbidity and mortality has been associated with such rapid turn around times from a study using the i-STAT to analyze blood lactate levels after congenital heart surgery. POCT has become established worldwide and finds vital roles in public health. Many researchers emphasize POCT as the normal standard of care in disaster situations. Potential operational benefits include more rapid decision making and triage, reduced operating times, high-dependency, postoperative care time, emergency room time, number of outpatient clinic visits, number of hospital beds required, ensuring optimal use of professional time and reduced of antimicrobial medication. At home or POCT tests, providing results within minutes of being administered, would allow for appropriate measures and rapid decisions about dental patients' care process. Characteristics and detection rate of SARS-CoV-2 in alternative sites and specimens related to dentistry has been extensively reviewed.

===== Bio-Orthogonal/Quantitative Non-Canonical Amino acid Tagging ===== Bio-Orthogonal/Quantitative Non-Canonical Amino acid Tagging (BONCAT/QuaNCAT) uses azidohomoalanine (AHA) to tag proteins. This allows isolation of newly created proteins for MS. However, using AHA requires predepletion of intracellular methionine and introduction of AHA, stressing the cell and potentially altering translation dynamics within. Similar to pSILAC, AHA methods require longer pulses, thus limiting their efficacy in quantifying nascent peptides.

The three substrates of this enzyme are 3-oxopropanoic acid, reduced nicotinamide adenine dinucleotide (NAD+), and water. Its products are malonic acid, reduced NADH, and a proton. This enzyme can use the alternative cofactor, nicotinamide adenine dinucleotide phosphate. This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is 3-oxopropanoate:NAD(P)+ oxidoreductase. This enzyme participates in beta-alanine metabolism.

Sources: en.wikipedia.org

Further detail

Skittles are produced in a wide variety of flavors and colors, including sour varieties. Skittles has hinted at new flavor releases on its Facebook page, using such statuses as "Locking myself in the Rainbow kitchen until I see some results!" A 2011 posting contained confirmation of a new flavor: "Putting the last touches on a new Skittles flavor. Tweak the Rainbow." In the United States and Canada, in 2013, Skittles replaced the lime-flavored Skittles with green apple, causing a backlash from many consumers. The lime flavor became part of the Darkside packets, which were discontinued in 2015 and followed up by the Orchards packets, which were discontinued in 2017. Lime was also part of the "Long Lost Lime" packets that came out in summer 2017 and 2018. The Darkside flavor was revived in 2019. In 2021, the "All Lime" packets containing only the lime flavor were released for a limited time. In September 2021, Skittles announced that the green apple-flavored Skittles would be replaced with the original lime flavor. In 2022, Skittles Gummies were released. In October 2024, Skittles released their own version of freeze-dried Skittles called Skittles POP'd. It comes in the Original and Sour Skittles flavors.

Despite this shift, bismuth therapies persisted in several regions, such as France, where they remained in use for specific stages of the disease until at least the late 1970s. "Milk of bismuth" (an aqueous suspension of bismuth hydroxide and bismuth subcarbonate) was marketed as an alimentary cure-all in the early 20th century, and has been used to treat gastrointestinal disorders. Bismuth subnitrate (Bi5O(OH)9(NO3)4) and bismuth subcarbonate (Bi2O2(CO3)) are also used in medicine.

An analgesic, also called an antalgic, painkiller, or pain reliever, is any member of the group of drugs used for pain management. Analgesics are conceptually distinct from anesthetics, which temporarily reduce, and in some instances eliminate, sensation, although analgesia and anesthesia are neurophysiologically overlapping and thus various drugs have both analgesic and anesthetic effects. Analgesic choice is also determined by the type of pain: For neuropathic pain, recent research has suggested that classes of drugs that are not normally considered analgesics, such as tricyclic antidepressants and anticonvulsants may be considered as an alternative. Various analgesics, such as many NSAIDs, are available over the counter in most countries, whereas various others are prescription drugs owing to the substantial risks and high chances of overdose, misuse, and addiction in the absence of medical supervision.

=== Inter-Tribal Environmental Council === Since 1992, the nation has served on Inter-Tribal Environmental Council. The mission of ITEC is to protect the health of Native Americans, their natural resources and their environment as it relates to air, land and water. To accomplish this mission, ITEC provides technical support, training, and environmental services in a variety of environmental disciplines.

Sources: en.wikipedia.org

Frequently asked questions

Semax 冻干粉可以常温保存吗?

一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受,但会加快降解风险。

配制好的溶液能放多久?

公开资料对此没有统一答案。普遍建议现配现用,或冷藏并在数日内用完。含甲硫氨酸的序列更易氧化,放置时间越长风险越高。

用什么方法检测 Semax 的纯度?

反相高效液相色谱是最常用的手段,配合质谱确认分子量。氨基酸组成分析和肽图分析可补充序列层面的验证。

What is Semax chemically?

It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.

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