Zoptarelin Doxorubicin

Various nanodrug vehicles were well-designed with complicated functions for tumor therapy. However, the unsatisfactory tumor delivery efficiency and uncertain off-target release became the stumbling block of the nanodrugs on the way to the clinic. Inspired by efficient tumor targeting ability of albumin, we reported a simplified biomimetic peptide-based vehicle synthesized by copolymerizing L-glutamyl-L-lysine unit (EK dimer, an intrinsic surface peptide pair from albumin) with L-phenylalanine (F) to encapsulate doxorubicin (Dox). The zwitterionic peptide shell based on EK pair made the system exhibit prolonged blood circulation by mimicking the surface function of albumin, and enhanced tumor penetration by liquefying gelated water molecules in tumor extracellular matrix (ECM). Meanwhile, the overexpressed enzymes (cathepsin B, CB) in tumor can trigger the degradation of the peptide scaffold so as to rapidly release Dox. This simplified albumin-mimicking approach can provide a promising nanodrug delivering platform for clinical application.

Electrochemical aptamer-based biosensors (EABs) have been developed for multiple important biomarkers for their convenient and real-time features. However, the application of EABs in complex biological fluids has been limited by the rapid loss of sensitivity and selectivity due to inactivation and biofouling of aptamer probes and electrodes. To address this issue, we report the preparation of a simple hydrogel-protected aptamer-based biosensor (HP-EAB) for direct detection of Doxorubicin (DOX) in whole blood. The aptamer provides excellent selectivity for the electrochemical sensor, allowing the prepared sensor to accurately detect DOX in a 50-fold diluted whole blood sample. The agarose hydrogel coating on the electrode surface allows the passage of small molecules while hindering the adsorption of biomolecules from the whole blood matrix to the electrode surface. The experimental results show that the prepared HP-EAB has high stability compared with the unprotected EAB, and the HP-EAB maintains excellent detection performance after 7 days of storage. The hydrogel coating can effectively reduce the non-specific response to the whole blood matrix and prolong the life-time of the sensor. When used to detect DOX in rabbit whole blood, the HP-EAB exhibited excellent detection performance with a detection limit of 25.9 nM (S/N = 3) and a detection range of 0.1 μM-50 μM. The developed HP-EAB provides an excellent platform for the rapid and accurate determination of important analytes in complex biological fluids.