Folate-Targeted Monodisperse PEG-Based Conjugates Made by Chemo-Enzymatic Methods for Cancer Diagnosis and Treatment

Int J Mol Sci. 2021 Sep 26;22(19):10347. doi: 10.3390/ijms221910347.


This paper focuses on preliminary in vitro and in vivo testing of new bivalent folate-targeted PEGylated doxorubicin (DOX) made by modular chemo-enzymatic processes (FA2-dPEG-DOX2). A unique feature is the use of monodisperse PEG (dPEG). The modular approach with enzyme catalysis ensures exclusive γ-conjugation of folic acid, full conversion and selectivity, and no metal catalyst residues. Flow cytometry analysis showed that at 10 µM concentration, both free DOX and FA2-dPEG-DOX2 would be taken up by 99.9% of triple-negative breast cancer cells in 2 h. Intratumoral injection to mice seemed to delay tumor growth more than intravenous delivery. The mouse health status, food, water consumption, and behavior remained unchanged during the observation.

Keywords: chemo-enzymatic synthesis; folate-targeted cancer diagnosis; in vitro screening; in vivo screening; multivalency; polymer conjugates.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Doxorubicin* / chemistry
  • Doxorubicin* / pharmacology
  • Female
  • Flow Cytometry
  • Folic Acid* / chemistry
  • Folic Acid* / pharmacology
  • Humans
  • Male
  • Mice
  • Mice, Nude
  • Nanoparticles* / chemistry
  • Nanoparticles* / therapeutic use
  • Triple Negative Breast Neoplasms* / diagnosis
  • Triple Negative Breast Neoplasms* / drug therapy
  • Triple Negative Breast Neoplasms* / metabolism
  • Xenograft Model Antitumor Assays


  • Doxorubicin
  • Folic Acid