Electrochemical Deposited Calcium Phosphate Nanomaterials with Micro‐Nano Interface for Capture and Non‐Invasive Release of Cancer Cells

Abstract

CTCs), which escape from primary tumor and invade into patient peripheral blood circulation system, take major responsibility in cancer metastasis. [2] CTCs contain plenty of information about the primary tumor and the variety of protein molecules at different cancer stage which will help researchers to comprehensively understand and assist to offer more detailed therapeutic schedule. [3] Therefore, CTCs have been regarded as tumor biomarkers and a real-time "liquid biopsy" signal in solid tumors. [4] Isolating CTCs from cancer patients' blood was the first step to research CTCs, which attracted huge attention because the number of CTCs was just one per hundred million of normal blood cells, where large amount of red blood cells and leukocytes exist in primary tumor. [5] It is a challenge to separate the CTCs from normal blood cells and maintain the cells' activity for a follow-up study. Currently, kinds of platforms have been developed for capturing CTCs, including different materials, such as nanoparticles, [6] nanowires, [7] nanotubes, [8] and different methods, such as magnetic separation, [9] flow cytometry, [10] cell size, [11] density gradient sedimentation, [12] and surface electrochemical property. [13] Different micro-structures integrated in microfluidic chips were used to capture and purify CTCs, [14] and enrich heterogeneous CTCs subpopulation. [15] Aptamer had been used widely for modification and precisely recognize target cancer cells. [16] But those methods have their inherent insufficiency, for example, immuno-magnetic bead capture has a weak basis of releasing target cells from magnetic makings, ferromagnetic compounds can shield reflected color of other stuff. Hence it is vital to control the concentration of immunomagnetic bead for further observation in fluorescence analysis. Different levels of damage are caused on cellular film in electrochemical collection where voltage is applied. The prior modification of microfluidic chips is time-consuming and complex, and skillful researcher is needed when applied in clinical test.The size and specific antigen of CTCs are utilized to separate and capture CTCs from patient peripheral blood samples. In addition, the microenvironments of CTCs are also utilized to identify CTCs from normal blood cells. It is reported that the pH range of tumor tissue is 6.2-6.9, which is lower than that in normal organs (7.3-7.4). CTCs and normal cells are dispersed A low cost and easily fabricated 3D micro-nano biocompatible calcium phosphate (CaP) microstructure platform is developed to efficiently capture and non-destructively release cancer cells. The thickness of CaP is ≈3 µm after 2.5 min deposition and increased to ≈12 µm after 10 min deposition. The void size between CaP nanosheets is increased when the electro deposition time is increased. This micro-nano bio-interface is suitable for cancer cell capturing and culturing. More than 90% for the EpCAM positive cells are captured on the CaP substrates where the specific anti-EpCAM antibody is modified. On th...

Mineralized Porphyrin Metal–Organic Framework for Improved Tumor Elimination and Combined Immunotherapy

“…Based on the obvious damage to cell activity, PCN was a suitable choice for making cells more sensitive for excess calcium ions. In addition, CaP could degrade in the acidic environment of lysosome and release calcium ions for calcium overload. − When endocytosed into the lysosome, PCa could cause a change of intracellular calcium concentration and produce singlet oxygen with near-infrared light irradiation, which had a synergistic and amplifying effect. Because both PDT and calcium overload could trigger immunogenic death, PCa could also trigger more immunogenic death to elicit antitumor immune response.…”