2790 | J. Mater. Chem. B, 2019, 7, 2790--2798 This journal is©The Royal Society of Chemistry 2019Cite this: J.Mater. Chem. B,2019,7, 2790A modular theranostic platform for tumor therapyand its metabolic studies†Ke Li,‡ Jiang-Lan Li,‡ Di-Wei Zheng, Xuan Zeng,* Chuan-Jun Liu * andXian-Zheng Zhang *Theranostic systems are able to detect and treat diseases with only one procedure, thus greatlylessening the pain of patients. Since each patient’s disease can be considered as a new clinical subtype,it is essential to develop theranostic nanomaterials with changeable functions for personal treatment.In this work, a novel modular theranostic platform was designed to control the stimuli-responsivedrug release. As a patch board, mesoporous silica nanoparticles (MSNs) were functionalized with a linearpH-responsive benzimidazole (Bz)-polyethylene glycol (PEG) chain containing a redox-responsiveferrocene (Fc) oxide stopper at the end. As the plug, the b-CD ring was initially located at the Bzposition. In an acidic tumor microenvironment, the pH sensitive Bz was protonated and the complexformation constant between Bz and b-CD decreased. At the same time, the complex formationconstant between Fc and b-CD increased remarkably. As a result, the b-CD ring would depart from thenanoparticle surface to the Fc position at pH 6.2 & 10 mM GSH, physically causing an ‘‘And’’ logic gatetype drug release. Herein, a ‘‘plug and play’’ method was used to achieve changeable functions with onlyone platform. By plugging modified b-CD into the patch board, theranostic systems with changeablefunctions can be achieved easily.IntroductionNanomedicine has already delivered a valuable set of researchtools and clinically useful devices in cancer treatment. Recently,the concept of theranostic nanomedicine has become a trendin nanomedicine research, which combines diagnostic andtherapeutic functions within a single nanomaterial. 1–3 Comparedwith the previous diagnostic or therapeutic systems in preclinicaldevelopment, theranostic systems are able to detect and treatdiseases with only one procedure, thus greatly lessening the painof patients. The visualization of therapeutic processes can directlyprovide information about cancer progress and the therapeuticeffect. 4–6 Since each patient’s disease can be considered as a newclinical subtype, 7,8 it is essential to develop theranostic nano-materials with changeable functions for personal treatment.In most of the proposed theranostic systems, functionsof diagnostics and therapeutics are bound together. 9,10 Thusboth therapeutic drugs and imaging contrast agents would beinjected at the same time even though only one function isneeded. Usually, the frequency of therapeutic drug injectionis high to ensure a satisfactory therapeutic ef f ect, while thefrequency of the imaging test is relatively low. And it isnecessary to link the cytotoxicity of materials with the amountof theranostic nanoparticles and with the internalizationnumber of theranostic nanoparticles over a period of time. 11For the reported theranostic systems with bound diagnosticand therapeutic functions, the imaging contrast agent has tobe injected unnecessarily during the frequent injection fortherapeutic treatment. 12–14 This fact would lead to an irrever-sible accumulation of contrast agents, which may cause seriousside effects at a high dose. Therefore, the use of multi-functional theranostic systems is wasteful and unnecessary inthis case, which greatly limits its universal applications.To avoid this situation, it is significant to design a new typeof theranostic system with the ability to change its functionsbased on only one platform.Clinically, the therapeutic ef f ect can be evaluated with theimaging measurement in terms of tumor volume, and usually ittakes weeks to months for the tumor to shrink. On the otherhand, the metabolite measurement is a real-time evaluationmethodtoassesstumorresponsestothetreatment. 15 Thechemicaltests of few components, such as lactate and pyruvate, providea quick and cheap method to monitor tumor conditions. 16–18In comparison, metabolomics measuring 10–100 indicators onceKey Laboratory of Biomedical Polymers of Ministry of Education & Department ofChemistry, Wuhan University, Wuhan 430072, P. R. China.E-mail: zeng_xuan@163.com, cjliu@whu.edu.cn, xz-zhang@whu.edu.cn;Fax: +86 27 6875 4509; Tel: +86 27 6875 5993† Electronic supplementary information (ESI) available: Materials and characteri-zation; FT-IR spectrum of modified MSN; and H&E staining images of heart, lung,liver, spleen, tumor and kidney. See DOI: 10.1039/c9tb00231f‡ These two authors contributed equally to this work.Received 1st February 2019,Accepted 14th March 2019DOI: 10.1039/c9tb00231frsc.li/materials-bJournal ofMaterials Chemistry BPAPERPublished on 14 March 2019. Downloaded by Shanghai University on 4/24/2020 6:33:51 AM. View Article OnlineView Journal | View Issue
