Overview
Tacrolimus is a macrolide immunosuppressant discovered in 1984 from Streptomyces tsukubaensis. It revolutionized transplant medicine by offering 10-100x greater potency than cyclosporine. The drug binds to FKBP-12 proteins, forming complexes that inhibit calcineurin phosphatase, ultimately blocking IL-2 transcription in T-cells. Pharmaceutical formulations include oral capsules (0.5-5mg), intravenous solutions, and topical ointments (0.03-0.1%). Its use expanded beyond liver/kidney transplants to include heart, lung, and stem cell transplants, as well as autoimmune conditions like severe atopic dermatitis.
Physical and Chemical Properties
Tacrolimus exhibits poor water solubility (4-12 μg/mL) but high lipid solubility (logP ~3), necessitating special formulations for bioavailability. The crystalline powder shows stability at neutral pH but degrades under strong acids/bases. Its UV absorption peaks at 210nm facilitates HPLC analysis. The molecule contains a 23-membered macrolide ring with hemiketal and α,β-unsaturated ester moieties. These structural features contribute to its specific binding with immunophilins. Polymorphism exists, with Form II being the most thermodynamically stable crystalline variant for pharmaceutical use.
Main Applications
In transplantation, tacrolimus forms the backbone of maintenance immunosuppression regimens, typically combined with mycophenolate and corticosteroids. Topical formulations treat moderate-to-severe atopic dermatitis unresponsive to conventional therapies. Emerging uses include prevention of graft-versus-host disease (GVHD) in hematopoietic stem cell transplantation and management of autoimmune hepatitis. Clinical trials explore its potential in nephrotic syndrome, rheumatoid arthritis, and inflammatory bowel disease, though these remain off-label applications.
Safety and Storage
As a potent cytotoxic agent, tacrolimus requires handling with nitrile gloves, goggles, and respiratory protection in powder form. Spills should be contained with absorbent materials and deactivated with dilute sodium hypochlorite solution. Long-term storage demands refrigeration (2-8°C) in amber glass vials with nitrogen purging to prevent oxidation. Working solutions in ethanol or DMSO remain stable for 3 months at -20°C. Degradation products can be monitored via HPLC with UV detection at 210nm.
B2B Procurement Guide
Pharmaceutical-grade tacrolimus must meet USP/EP monograph specifications with ≥98.5% purity. Key quality documents include Certificate of Analysis (COA), Drug Master File (DMF), and stability data. Bulk procurement typically requires minimum orders of 10-100g with lead times of 4-8 weeks. For research use, small quantities (1-100mg) are available from specialty chemical suppliers with purity ≥95%. Price varies significantly by quantity and certification level - GMP-grade material commands 3-5x premium over laboratory-grade. Importers should verify DEA/FDA clearance requirements for controlled substances.
Related Manufacturers
- 主营：酒渣碱、异常山乙素、芦丁标准品、182261、对照品标准品
- 主营：标准品、中药对照品、试剂、精油、技术服务、提取定制、化合物合成、分析检测、色谱柱、天然产物
- 主营：182261、香精香料化妆品、中药对照品