Cefprozil, a semi-synthetic antibiotic, has been used in pediatric therapy. The purpose of this study was to improve the yield of cefprozil and obtain purer product in an aqueous two-phase system composed of P ADB and P MDB . P ADB and P MDB were synthesized using acrylic acid, methacrylic acid, 2-dimethylaminoethyl methacrylate, and butyl methacrylate. Cefprozil was synthesized with 7-amino-3-(1-propenyl)-4-cephalosporanic acid (7-APRA) as the main ring, ( R )-amino-(4-hydroxyphenyl) acetic acid methyl ester hydrochloride (D-HPGME-HCl) as the acyl donor and the immobilized penicillin acylase as the catalyst. 7-APRA and D-HPGME-HCl were concentrated in the P MDB -rich phase, while cefprozil was in the P ADB -rich phase. The optimal partitiona coefficient of cefprozil was 1.84 with 40 mM KSCN, while the enzyme reaction yield of cefprozil reached 99.39% compared with 77.61% in the aqueous-phase system. The recovery of the two copolymers was up to 96.01% at pH 3.54. After crystallization, the purity of the product reached 88.02%, and no copolymer remained in the product. The combination of cefprozil∙DMF was detected by gas chromatography-mass spectrometry, FT-IR spectroscopy, thermogravimetric analysis, and electrospray ionization mass spectrometry. The results showed that no chemical bond existed between cefprozil and DMF.
Cefprozil is a second-generation cephalosporin antibiotic, is widely used in the treatment of bronchitis and bacterial infections. Chemical synthesis methods have the disadvantage of complicated steps and high toxicity, while enzymatic synthesis in aqueous phase can be incomplete and susceptible to side reactions. To address these issues, a new green preparation method for cefprozil was developed by combining an enzymatic reaction with a 20 % ethylene oxide/80 % propylene oxide (v/v) random copolymer (EO 20 PO 80 )/water aqueous two-phase system (ATPS). In this method, the yield of the enzyme reaction increased from 80.3 % in the aqueous system to 93.1 %. The resulting products were mainly precipitated, with a small amount remaining in the two-phase solution. The distribution coefficient was 1.44. After washing and purification , the purity of the precipitated product reached 97.3 %, with no remaining polymer. The product in the two-phase solution was purified by crystallization using DMF . The total recovery of the precipitated and solution products after crystallization was 78.9 %. Finally, molecular simulation technology was used to explain how polymers promote cefprozil precipitation at a microscopic level.
Aqueous two-phase systems are efficient purification methods for bioproducts. However, recovery difficulty of the copolymers forming aqueous two-phase systems becomes obstacle in scale-up application. In the study, novel recyclable aqueous two-phase systems have been developed by using two thermo-responsive copolymers, P NE and P VAm . Copolymer P NE was copolymerized by using N-isopropylacrylamide and ethyl methacrylate as monomers, and P VAm was synthesized by using N-vinylcaprolactam and acrylamide as monomers. The lower critical solution temperatures of P NE and P VAm are 28.7 °C and 35.6 °C, respectively. The recoveries of both polymers can reach over 95%. The minimal and maximal partition coefficient of cefprozil was 0.33 at 50 mM NH 4 F and 6.55 at 70 mM LiCl. Two empirical equations were used to correlate with experimental binodal curve. Partition coefficients of cefprozil examined in the ATPS were correlated with tie-line length and calculated partition coefficient.
危险品化学品经营许可证（带存储）