Melatonin

Melatonin

Melatonin (N-acetyl-5-methoxytryptamine) is a naturally occurring indoleamine produced primarily by the pineal gland. It is critically important for governing circadian rhythms, seasonal physiological cycles, and the body’s antioxidant defense systems. In laboratory research, melatonin is extensively employed to probe the fundamental mechanisms underlying sleep regulation, cellular cytoprotection, and neuroendocrine balance. This product is manufactured and intended solely for laboratory and analytical research purposes.

Melatonin Overview

Melatonin is biosynthesized from the essential amino acid tryptophan through a multi-step enzymatic pathway, utilizing serotonin as a key intermediate. Its secretion is dynamically controlled by the environmental light-dark cycle, resulting in peak plasma concentrations during the nighttime hours. In experimental and in-vitro studies, melatonin acts as a pleiotropic signaling molecule, contributing to the precise calibration of circadian timing, the preservation of mitochondrial stability, the maintenance of redox homeostasis, and sophisticated immune system modulation.

Scientific investigations further validate melatonin’s function as a potent intrinsic antioxidant, demonstrating its capacity to directly scavenge harmful reactive oxygen and nitrogen species while simultaneously augmenting the catalytic activity of critical antioxidant enzymes, including superoxide dismutase, catalase, and glutathione peroxidase. Furthermore, melatonin is actively explored as a pivotal regulatory molecule in the control of reproductive hormones, promotion of neuroprotection, and the mitigation of cellular aging processes.

Melatonin Structure

Parameter

Value

Molecular Formula

C13H16N2O2

Molecular Weight

232.28 Da

Observed Mass (Batch # 2025027)

232.3 Da

Purity (HPLC, LCMS-confirmed)

99.17 %

Form

Crystalline powder

Analysis Method

Reverse-phase HPLC (UV 280 nm) and LCMS (ESI+ mode), calibrated with reference standard.

Appearance

White to faintly off-white crystalline powder

Melatonin Research

Circadian Rhythm and Sleep Regulation

Melatonin exerts its primary action by engaging with the MT1 and MT2 G-protein coupled receptors, which are strategically located within the suprachiasmatic nucleus (SCN) of the hypothalamus, recognized as the body's master circadian pacemaker. Studies confirm its ability to distinctly modulate and phase-shift circadian rhythms, establishing it as an essential chemical probe for investigating chronobiology and the precise molecular mechanisms of sleep regulation.

Antioxidant and Mitochondrial Effects

Research unequivocally demonstrates that melatonin possesses both direct free-radical scavenging and indirect enzymatic upregulation antioxidant properties. It effectively neutralizes reactive species and enhances the expression of a broad spectrum of protective antioxidant enzymes, positioning it as a fundamental molecule in the study of oxidative stress pathologies and the maintenance of mitochondrial structural and functional health.

Neuroendocrine and Immune Modulation

Melatonin’s sophisticated role in governing neuroendocrine activity and its deep involvement in immune function have been extensively documented. Experimental findings indicate that it significantly contributes to the balanced production of cytokines, the effective modulation of inflammatory responses, and the systemic regulation of the hypothalamic–pituitary axis (HPA).

Cellular Protection and Aging

Investigations into melatonin’s profound cytoprotective and anti-aging potential illuminate its capacity to stabilize mitochondrial membrane potential, preserve the structural integrity of mitochondria, and effectively mitigate the DNA damage intrinsically linked to the aging process. Its dual antioxidant and anti-inflammatory mechanisms make it a high-priority research target in studies concerning cellular senescence and the pursuit of longevity.

Article Author

This literature review and associated content were compiled, edited, and professionally organized by Dr. Russel J. Reiter, Ph.D., an internationally recognized Professor of Cellular Biology at the University of Texas Health Science Center at San Antonio.

Dr. Reiter is globally acknowledged as the leading authority and foundational expert in melatonin biology. His transformative research has illuminated melatonin’s diverse and critical roles in the comprehensive regulation of circadian rhythms, the energetic support of mitochondrial performance, the systemic combating of oxidative stress, and the deep influence on cellular aging. Across his extensive and pioneering career, he has fundamentally advanced the scientific understanding of melatonin as both a crucial neuroendocrine signal and a remarkably potent antioxidant compound.

Scientific Journal Author

The collaborative and impactful investigations conducted by Dr. Russel J. Reiter, Dr. Dun-Xian Tan, and their team of research associates have been absolutely instrumental in fully characterizing the multifaceted and comprehensive biological properties of melatonin.

Their extensive and collective body of work has defined the entirety of melatonin’s mechanisms of action, spanning from its receptor-mediated signaling pathways to its critical involvement in redox regulation and its function in mitochondrial defense. Through their continuous, cutting-edge research, the Reiter–Tan group has profoundly expanded the core fields of chronobiology, cellular energy metabolism, and cellular resilience, cementing melatonin's position as a cornerstone molecule in both basic physiological and translational therapeutic science.

Reference Citations

• Reiter RJ, Tan DX, Galano A. "Melatonin: exceeding expectations." Physiology (Bethesda). 2014;29(5):325-333. https://pubmed.ncbi.nlm.nih.gov/25180259/
• Hardeland R, Cardinali DP, Srinivasan V, et al. "Melatonin-a pleiotropic, orchestrating regulator molecule." Prog Neurobiol. 2011;93(3):350-384. https://pubmed.ncbi.nlm.nih.gov/21193011/
• Acuña-Castroviejo D, Escames G, Venegas C, et al. "Melatonin in the regulation of cellular energy metabolism: mitochondrial protection." Int J Mol Sci. 2014;15(4):6908-6938. https://pubmed.ncbi.nlm.nih.gov/24752558/
• Arendt J, Skene DJ. "Melatonin as a chronobiotic." Sleep Med Rev. 2005;9(1):25-39. https://pubmed.ncbi.nlm.nih.gov/15649736/
• Pandi-Perumal SR, Srinivasan V, Maestroni GJM, et al. "Melatonin: Nature's most versatile biological signal." FEBS J. 2006;273(13):2813-2838. https://pubmed.ncbi.nlm.nih.gov/16817850/
• Cardinali DP, Pevet P. "Basic aspects of melatonin action." Sleep Med Rev. 1998;2(3):175-190. https://pubmed.ncbi.nlm.nih.gov/15310406/
• Claustrat B, Leston J. "Melatonin: physiological effects in humans." Neurochirurgie. 2015;61(2-3):77-84. https://pubmed.ncbi.nlm.nih.gov/ 25818301/
• Tan DX, Manchester LC, Terron MP, et al. "Melatonin as a natural antioxidant: from molecular mechanisms to clinical significance." Brain Res Bull. 2007;73(1-3):203-213. https://pubmed.ncbi.nlm.nih.gov/17499606/
• Reiter RJ, Rosales-Corral S, Tan DX, et al. "Melatonin as a mitochondria-targeted antioxidant: one molecule, multiple actions." Cell Mol Life Sci. 2017;74(21):3863-3881. https://pubmed.ncbi.nlm.nih.gov/28567501/
• National Center for Biotechnology Information. "Melatonin compound summary," https://pubchem.ncbi.nlm.nih.gov/compound/Melatonin

ALL ARTICLES AND PRODUCT INFORMATION PROVIDED ON THIS WEBSITE ARE FOR INFORMATIONAL AND EDUCATIONAL PURPOSES ONLY.

The products offered on this website are furnished for in-vitro studies only. In-vitro studies (Latin: in glass) are performed outside of the body. These products are not medicines or drugs and have not been approved by the FDA to prevent, treat or cure any medical condition, ailment or disease. Bodily introduction of any kind into humans or animals is strictly forbidden by law.STORAGE

Storage Instructions

All products are manufactured using a lyophilization (freeze-drying) process, which is designed to preserve maximum stability for approximately 3-4 months during shipping and initial handling. After reconstitution with bacteriostatic water, peptide solutions must be maintained under refrigeration to ensure their efficacy, remaining stable for up to 30 days.

Lyophilization, also technically known as cryodesiccation, is a specialized dehydration method where peptides are first frozen and then subjected to a high vacuum. This process facilitates the sublimation of water directly from a solid ice phase to a gaseous phase, resulting in a stable, white crystalline structure termed a lyophilized peptide. This powder form can be safely kept at room temperature for a period until it is accurately reconstituted with bacteriostatic water for experimental use.

For long-term preservation, extending over several months to years, the ideal storage recommendation is to place the lyophilized peptides in a freezer at -80 degrees C (-112 degrees F). Freezing under these ultra-low temperature conditions is essential to maintain the peptide’s structural integrity and guarantee maximum long-term stability.

Upon receipt of the peptides, it is crucial to immediately keep them cool and fully protected from any light exposure. For short-term experimental usage—ranging from a few days to several months—refrigeration below 4 degrees C (39 degrees F) is entirely adequate. Lyophilized peptides are generally confirmed to remain stable at ambient room temperature for several weeks, which makes this acceptable storage for shorter periods preceding immediate use.

Best Practices For Storing Peptides

Proper storage of research peptides is an absolutely critical factor in preserving their structural integrity and ensuring the accuracy and reliability of all resultant laboratory data. Adhering to correct storage protocols helps proactively prevent contamination, minimize oxidation, and limit degradation, thereby ensuring that the peptides remain effective and stable for extended experimental periods. While some peptide sequences are inherently more susceptible to breakdown than others, rigorously applying the following best storage practices can significantly prolong their effective lifespan and maintain their integrity.

• Upon Receipt and Short-Term Use: Peptides should be kept cool and strictly shielded from light immediately upon arrival. For short-term use—ranging from a few days up to several months—refrigeration below 4 degrees C (39 degrees F) is the recommended standard. Lyophilized peptides typically exhibit stability at room temperature for several weeks, which is acceptable for very brief storage durations.
• Long-Term Preservation: For maximum long-term preservation spanning several months or years, peptides must be stored in a freezer set at -80 degrees C (-112 degrees F). Freezing under these specific conditions provides the optimal environment for stability and prevents structural degradation.
• Minimize Freeze-Thaw Cycles: It is paramount to minimize repetitive freeze-thaw cycles, as these rapid and repeated temperature fluctuations can significantly accelerate degradation of the peptide structure.
• Avoid Frost-Free Freezers: Researchers should avoid using frost-free freezers, as these units inherently cycle through temperature variations during their automatic defrosting periods, which can compromise overall peptide stability.

Preventing Oxidation and Moisture Contamination

It is essential to diligently protect peptides from all exposure to atmospheric air and moisture, as both environmental factors can severely compromise their chemical stability. Moisture contamination is a significant risk, particularly when retrieving peptides from a cold freezer environment. To actively prevent condensation from forming on the cold peptide material or inside its storage container, always allow the sealed vial to reach room temperature before carefully opening it.

Minimizing air exposure is equally critical for long-term preservation. The peptide container must remain tightly closed as much as possible, and immediately after carefully removing the required amount of material, it should be promptly resealed. Storing the remaining lyophilized peptide under a dry, inert gas atmosphere—such as purified nitrogen or argon—can further prevent oxidative damage. Peptides that contain susceptible amino acid residues like cysteine (C), methionine (M), or tryptophan (W) are particularly sensitive to air oxidation and require extra careful handling and storage.

To best preserve long-term structural stability, consistently avoid frequent thawing and refreezing of the entire bulk quantity. A highly recommended practical approach is to carefully divide the total peptide quantity into a series of smaller, single-use aliquots, each specifically designated for an individual experimental run. This aliquoting method drastically reduces repeated exposure to both air and temperature changes, thereby maintaining optimal peptide integrity over the total storage duration.

Storing Peptides In Solution

Peptide solutions inherently possess a significantly shorter shelf life and are considerably more susceptible to bacterial and chemical degradation compared to their lyophilized forms. Peptides containing highly reactive residues such as cysteine (Cys), methionine (Met), tryptophan (Trp), aspartic acid (Asp), glutamine (Gln), or an N-terminal glutamic acid (Glu) tend to degrade substantially more rapidly when stored in an aqueous solution.

If storing the peptide in solution is an unavoidable necessity for the experiment, the best practice is to utilize sterile buffers maintained within a controlled pH range of 5 to 6. The entire solution must be meticulously divided into multiple aliquots to minimize the detrimental effects of repeated freeze-thaw cycles, which are known to accelerate chemical degradation. Under consistent refrigerated conditions at 4 degrees C (39 degrees F), the majority of peptide solutions are expected to remain stable for a period of up to 30 days. However, for peptide sequences known to be inherently less stable, they should be kept frozen when not scheduled for immediate use to best preserve their structural integrity.

Peptide Storage Containers

The containers selected for storing peptides must meet specific criteria: they should be impeccably clean, transparent for visibility, highly durable, and chemically resistant to common laboratory reagents. They must also be appropriately sized to match the exact quantity of peptide being stored, a practice that minimizes the detrimental presence of excess air space above the material. Both high-quality glass and laboratory-grade plastic vials are suitable storage options. Plastic varieties are typically manufactured from either polystyrene or polypropylene. Polystyrene vials offer superior clarity, allowing easy visibility, but they provide limited chemical resistance. In contrast, polypropylene vials offer much greater chemical resistance but are typically translucent rather than perfectly clear.

High-quality, borosilicate glass vials provide the absolute best overall characteristics for long-term peptide storage, offering a combination of clarity, structural stability, and superior chemical inertness. However, it is common industry practice for peptides to be shipped in plastic containers to minimize the risk of physical breakage during transit. If necessary, peptides can be safely and easily transferred between suitable glass and plastic vials to perfectly accommodate specific long-term storage or immediate experimental handling requirements.

Peptide Storage Guidelines: General Tips

When actively storing research peptides, consistently following these comprehensive best practices is critical to maintain structural stability and proactively prevent chemical degradation:

• Store all peptides in a cold, dry, and dark environment.
• Avoid repeated freeze-thaw cycles, as these significantly compromise peptide integrity.
• Minimize all exposure to air to reduce the risk of debilitating oxidation.
• Protect peptides from light, which can induce structural and chemical changes.
• Do not store peptides in solution long term; keep them in the stable lyophilized form whenever practically possible.
• Divide the total peptide quantity into small aliquots based on precise experimental needs to prevent unnecessary handling and environmental exposure.