pH-responsive mesoporous Fe_(2)O_(3)–Au nanomedicine delivery system with magnetic targeting for cancer therapy

Chemotherapy is the prime tool for the clinical treatment of cancer.The efficiency of treatment has been greatly improved with the assistance of nanomedicine delivery systems.However,it still meets the challenge of ineffi-cient drug delivery and damage to normal tissues caused by uncontrolled drug release.Considering the various processes of nanomedicine acting on cancer cells,a pH-responsive mesoporous Fe_(2)O_(3)–Au nanomedicine delivery system with magnetic targeting was designed to achieve controlled drug release and improve the safety and ef-ficiency.Fe_(2)O_(3) particles were constructed with external mesopores and internal hollow structures,while Au nanoparticles were connected on the surface of Fe_(2)O_(3) particles through pH-responsive valence bonds to encapsulate the drug.The Fe_(2)O_(3)–Au nanomedicine delivery system was equipped with magnetic targeting function,which could be induced by an external magnetic field to increase the drug concentration to kill cancer cells as well as reduce damage to normal cells.Meanwhile,based on the pH-responsive feature,the drug embedded could only be released in the weakly acidic condition of the cancer environment,while the nanomedicine delivery system remained closed in normal tissues.The Fe_(2)O_(3)–Au nanomedicine delivery system possessed the functions of pH responsiveness and magnetic targeting,enhancing safety and efficiency and providing a promising method for cancer therapy.

Multifunctional quantum dots and liposome complexes in drug delivery

Incorporating both diagnostic and therapeutic functions into a single nanoscale system is an effective modern drug delivery strategy. Combining liposomes with semiconductor quantum dots（QDs） has great potential to achieve such dual functions, referred to in this review as a liposomal QD hybrid system（L-QD）. Here we review the recent literature dealing with the design and application of L-QD for advances in bio-imaging and drug delivery. After a summary of L-QD synthesis processes and evaluation of their properties, we will focus on their multifunctional applications, ranging from in vitro cell imaging to theranostic drug delivery approaches.

Pediatric ocular nanomedicines：Challenges and opportunities

The eye is a highly complex,yet readily accessible organ within the human body.As such,the eye is an appealing candidate target for a vast array of drug therapies.Despite advances in ocular drug therapy research,the focus on pediatric ocular drug delivery continues to be highly underrepresented due to the limited number of degenerative ocular diseases with childhood onset.In this review,we explore more deeply the reasons underlying the disparity between ocular therapies available for children and for adults by highlighting diseases that most commonly afflict children（with focus on the anterior eye） and existing prognoses,recent developments in ocular drug delivery systems and nanomedicines for children,and barriers to use for pediatric patients

Artificial tumor microenvironment regulated by first hemorrhage for enhanced tumor targeting and then occlusion for synergistic bioactivation of hypoxia-sensitive platesomes

The unique characteristics of the tumor microenvironment(TME)could be exploited to develop antitumor nanomedicine strategies.However,in many cases,the actual therapeutic effect is far from reaching our expectations due to the notable tumor heterogeneity.Given the amplified characteristics of TME regulated by vascular disrupting agents(VDAs),nanomedicines may achieve unexpected improved efficacy.Herein,we fabricate platelet membrane-fusogenic liposomes(PML/DP&PPa),namely“platesomes”,which actively load the hypoxia-activated pro-prodrug DMG-PR104A(DP)and physically encapsulate the photosensitizer pyropheophorbide a(PPa).Considering the different stages of tumor vascular collapse and shutdown induced by a VDA combretastatin-A4 phosphate(CA4P),PML/DP&PPa is injected 3 h after intraperitoneal administration of CA4P.First,CA4P-mediated tumor hemorrhage amplifies the enhanced permeation and retention(EPR)effect,and the platesome-biological targeting further promotes the tumor accumulation of PML/DP&PPa.Besides,CA4P-induced vascular occlusion inhibits oxygen supply,followed by photodynamic therapy-caused acute tumor hypoxia.This prolonged extreme hypoxia contributes to the complete activation of DP and then high inhibitory effect on tumor growth and metastasis.Thus,such a combining strategy of artificially-regulated TME and bio-inspired platesomes pronouncedly improves tumor drug delivery and boosts tumor hypoxia-selective activation,and provides a preferable solution to high-efficiency cancer therapy.