Abstract
As a drug delivery system (DDS), traditional mesoporous silica nanoparticles (MSNs) suffer from bioaccumulation in vivo and premature drug release in systemic circulation due to low degradation rate and lack of protective gatekeeper. Herein, we developed a safe and intelligent DDS with characteristics of pH-responsive biodegradation and controlled drug release based on mesoporous silica composite nanoparticles (MSCNs) capped with ZnO quantum dots (ZnO QDs). Acidic degradable MSCNs were successfully synthesized by doping Ca2+ and PO43− into the MSNs’ framework. The in vitro doxorubicin hydrochloride (DOX) release was inhibited at neutral pH 7.4 but triggered significantly at pH 5.0 due to the dissociation of ZnO caps. The internalization behavior and cytotoxicity of 4T1 cells indicated MSCNs-ZnO could efficiently deliver DOX into the cells with significant antitumor activity. Such a DDS with pH-responsive biodegradation and controlled drug release has promising potential for cancer therapy.
Highlights
Mesoporous silica nanoparticles (MSNs) are widely employed in biomedical fields such as bioimaging [1], drug delivery [2], cancer diagnosis and therapy [3,4]
NH2), the as-prepared ZnO quantum dots (ZnO quantum dots (QDs)) were well-ultrasonically dispersed in 20 mL dimethyl formamide (DMF) followed by addition of 100 μL APTES, the mixture was stirred for 20 min at 120 °C
mesoporous silica composite nanoparticles (MSCNs)-NH2 were dispersed in 10 mL DMF including 86 mg succinic anhydride, which was vigorously stirred at room temperature for 24 h under nitrogen protection
Summary
Mesoporous silica nanoparticles (MSNs) are widely employed in biomedical fields such as bioimaging [1], drug delivery [2], cancer diagnosis and therapy [3,4]. Explored a mesoporous silica-calcium phosphate (MS-CAP) hybrid nanocarrier with a fast pH-responsive biodegradation in 24 h by doping CAP precursors (Ca2+ and PO4 3− ) into a silica matrix [31] These as-prepared hybrid MSNs have good degradability, the loaded drug molecules in the interior space would encounter the issue of premature leakage through the open pores into systemic circulation. ZnO quantum dots (ZnO QDs) with the merits of straightforward synthesis procedure, low-cost, health-friendly, etc., are capable of plugging drugs to avoid premature release They are stable and safe in a neutral environment and can readily be dissolved in an acidic environment, promoting them as the outstanding candidates of pH-responsive gatekeepers [36,37,38]. Schematic illustration of ZnO-capped mesoporous silica composite nanoparticles drug delivery system (DDS) and its procedure of pH-responsive degradation and drug release.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
