Overview
Carboxyl-terminated polyethylene glycol (COOH-PEG) is a polyethylene glycol (PEG) derivative functionalized with a reactive carboxyl group at one or both termini. It serves as a versatile linker in bioconjugation due to its water solubility, biocompatibility, and ability to form stable amide bonds with amines via EDC/NHS chemistry. COOH-PEG is synthesized through controlled anionic polymerization, followed by carboxylation. Its molecular weight and functionality (mono-/bis-carboxyl) can be tailored for specific applications. As a key building block in biomedical and materials science, COOH-PEG bridges synthetic polymers with biomolecules like proteins, peptides, or nanoparticles. Its non-immunogenic properties and tunable hydrophilicity make it indispensable in FDA-approved therapeutics and advanced research.
Physical and Chemical Properties
COOH-PEG exhibits PEG’s characteristic properties—high water solubility, low toxicity, and resistance to protein adsorption—while the carboxyl group adds reactivity for covalent coupling. The compound’s viscosity ranges from liquid (low MW) to waxy solid (high MW). Its hydroxyl groups can hydrogen-bond, enhancing solubility in polar solvents. The carboxyl group’s pKa is ~4.5, enabling efficient activation at neutral pH. Thermal stability is limited (degradation starts at ~200°C), and hygroscopicity necessitates dry storage. Fourier-transform infrared spectroscopy (FTIR) typically confirms carboxyl presence via a C=O stretch at 1710 cm⁻¹. Gel permeation chromatography (GPC) determines molecular weight distribution.
Main Applications
1. **Drug Delivery**: COOH-PEG modifies liposomes or polymeric nanoparticles to prolong circulation time (PEGylation) and enable targeted drug release. For example, PEGylated doxorubicin (Doxil®) uses carboxyl groups for ligand attachment. 2. **Bioconjugation**: The carboxyl group reacts with amines in antibodies, enzymes, or peptides to create stable conjugates for diagnostics (e.g., ELISA probes) or therapeutics (ADC—antibody-drug conjugates). 3. **Hydrogels**: Crosslinked COOH-PEG forms biocompatible hydrogels for tissue engineering or wound dressings. Adjusting PEG chain length controls mesh size and mechanical strength. 4. **Surface Modification**: COOH-PEG coatings reduce biofouling on medical devices (e.g., catheters) and sensors while enabling subsequent functionalization.
Safety and Storage
COOH-PEG is generally safe (LD50 >5g/kg, oral, rats) but may irritate eyes/skin. Use nitrile gloves and goggles during handling. Avoid inhalation of powder; employ local exhaust ventilation. Storage requires moisture control: seal containers under nitrogen or argon, and add desiccants. For long-term stability, store at 2–8°C. Solutions in water or buffer are stable for weeks at 4°C but should be sterile-filtered (0.22µm) to prevent microbial growth. Monitor for oxidation (yellowing indicates degradation).
B2B Procurement Guide
Industrial buyers should prioritize: 1. **Specifications**: Request certificates of analysis (CoA) for molecular weight (Mn/Mw), PDI (<1.2 preferred), and carboxyl content (titration data). 2. **Suppliers**: Choose GMP-compliant manufacturers (e.g., Sigma-Aldrich, JenKem Technology) for pharmaceutical-grade material. Custom synthesis is available for unique MW or functionalities. 3. **Batch Consistency**: Verify reproducibility via HPLC/GPC and NMR. Small trial orders are recommended before bulk purchases. 4. **Logistics**: Cold-chain shipping is advisable for high-MW COOH-PEG to prevent melting/aggregation. Bulk pricing often applies at >1kg quantities.
Related Manufacturers
- 主营：[]
- 主营：[]
- 主营：乙二醇、油酸丁酯、防腐涂料、丙烯酸环氧、缩水甘油酯、金属防锈剂、工业清洗剂、石油磺酸钡、甲基吡咯烷酮、液体丁腈橡胶、戊二酸二甲酯、橡胶制品改性剂、注浆堵漏泡花碱
- 主营：[]
- 主营：[]
- 主营：400peg400、乳化剂、硅藻土、聚乙二醇、三乙醇胺、醚硫酸钠、聚氧乙烯醚、椰子油脂肪酸
- 主营：三乙醇胺、VAE707乳液、乙二醇、聚乙二醇、三异丙醇胺、甲基二乙醇胺、一水柠檬酸、卡松、糖蜜、一乙醇胺、二乙醇胺、羟乙基二异丙醇胺、二乙醇单异丙醇胺、一异丙醇胺、二异丙醇胺
- 主营：甲氧基聚乙二醇、氨基聚乙二醇、羧基聚乙二醇、巯基聚乙二醇、羟基聚乙二醇、马来酰亚胺聚乙二醇、四臂聚乙二醇、荧光素聚乙二醇、叠氮聚乙二醇、硅烷聚乙二醇、炔基聚乙二醇、生物素聚乙二醇、丙烯酸酯聚乙二醇、活性脂聚乙二醇、Boc保护基团聚乙二醇、Fmoc保护基团聚乙二醇、生物素小分子PEG衍生物、甲氧基小分子PEG衍生物
- 主营：2d碳化钒、单层mbene、陶瓷材料、聚乙二醇、mab相材料、mbene前驱体、ti3c2tx柔性膜、免疫因子纳米载体服务
- 主营：反应活、hydrazide、催化剂、修饰剂、糖蛋白、连接子、激动剂、聚合物、活性脂、胆固醇、钆特酸、催化性、dna标记、络合剂、荧光试剂、雨蛙素、乙二胺、ped结构、衍生物、化合物、链接剂、反应物、生物素
- 主营：在水中、包含肽、含叠氮、丙炔基、由氨基、菁染料、peg单元、具有炔、胺hcl盐、阿尔法、催化剂、peg试剂、结构式、氨基nh2、3694-51-7、碘化物、4727-50-8、具有两、带有炔、磺酸基、3065-79-0、aminopeg8、甲基九、bcn基团、荧光素
- 主营：微球、聚乳酸、聚乙丙交酯、聚乙二醇、多臂聚乙二醇、聚乙二醇二胺、四臂聚乙二醇、PEG、PLGA、药物载体、水凝胶原料
- 主营：PLGA、透明质酸、聚乙内酯、磷脂聚乙二醇、胆固醇聚乙二醇、功能化聚乙二醇、硬脂酸聚乙二醇、聚乳酸、葡聚糖、DOPE
- 主营：纳米颗粒、脂质体
- 主营：嵌段共聚物、合成磷脂、荧光染料、氨基修饰聚乙二醇、PEG、点击化学、量子点
- 主营：上转换纳米粒子、嵌段聚合物、纳米材料、聚乙二醇PEG衍生物、荧光染料、金纳米粒、银纳米粒、二氧化硅、聚苯乙烯、四氧化三铁
- 主营：染色液、新材料、水苏糖、PEG修饰剂、阻燃剂、氮化锶、蒽醌紫、氧氟酸、胎盘肽、喹烯酮、钒酸铵、硫酸锂、钒酸铈、硫酸锶、降钙素、紫苏烯、锂电池、布洛芬、丁酸铝、锑酸钠、烟酰胺、牛磺酸、褪黑素、鸡蛋白、磷酸铁、丙酸铵
- 主营：金纳米、三角片、麦芽糖、修饰tio2、羟丙基、ito薄膜、氮化钛、tio2纳米、碳粉tio2、pd纳米笼、水溶伊红、纳米复合、磁性纳米、蛋白芯片、包硅金银、硅纳米线、包硅纳米、硅纳米管、螯合树脂、油溶性银、复合材料、薄膜定制、纳米粒子