The Study Of Cell Capture/Release Based On Near Infrared Response System

Circulating tumor cells in peripheral blood are important indications of tumor metastasis and recurrence.However,there are few circulating tumor cells in peripheral blood of cancer patients,with about one tumor cell in 10⁶ blood cells,which requires the detection method can detect tumor cells accurately and efficiently from a large number of non target cells.In addition,the non-destructive release study of CTCs is also a difficult challenge.Therefore,it is necessary to establish a mild CTCs release system to obtain highly purified and active CTCs,which is convenient for subsequent culture and related detection.The study plays an importent role in early diagnosis and prognosis evaluation.In this paper,the photo-sensitive polymer is combined with the upconversion luminescent material,and the release of CTCs is achieved by the photo-isomerization or photodeoxicity of the photo-sensitive polymer under mild near-infrared irradiation.This technique is few influence to cell activity.The photosensitive chip can be repeatedly used,combined with the sustainable development of society.Specific work as follows:The effect of cell activity is small,and the unique release of photopolymer can be used to realize the capture and release cycle of CTCs,which makes the photosensitive chip reusable and closely integrated with the sustainable development society.The work is listed as follows:1.?-NaYF₄:Yb³⁺/Er³⁺/Gd³⁺and?-NaYF₄:Yb³⁺/Tm³⁺were prepared by simple hydrothermal method.The factors of reaction temperature,time and the concentration of rare earth ion have influence on the particle size,crystal type and luminescent properties of nanorods.The upconversion nanorods are synthesized by hydrothermal method,which have the advantages of uniform particle size,uniform crystal phase and high luminous intensity,and the nanorods have the advantage in biomedical applications.The double-doped?-NaYF₄upconverted nanorods were synthesized by using NaYF₄ as the luminescent matrix material.The length,diameter and crystal form of the upconverted nanorods can be known by SEM and XRD.Under the 980nm near-infrared irradiation,UCNPs have different emission light in the visible and ultraviolet regions,which can control the photopolymer to achieve photo-isomerization or chain-broken.In addition,we use the St?ber method to coat a layer of SiO₂ on the surface of upconversion nanorods,which makes UCNP have better water solubility and biocompatibility.2.We have studied the poly?o-nitrobenzyl-methacrylate-co-methyl-methacrylate-co-poly-?ethylene-glycol?-methacrylate??PNMP?,whichisdifferentfromthe photoinduced isomerization PAA-Azo.The nitrobenzyl was broken down in the near infrared irradiation,polymer was dissolved rapidly in the solution pH>7,and was not dissolved in the solution PH<7.The results of FI-IR and NMR show that the synthesized products are consistent with the expected results.After the capture of the cells,the PNMP was irradiated under the 980nm NIR,the results can be obtained by inverted fluorescence microscopy.By the method of dissolving the photosensitive polymer,the cells can be more effective release.This technology can improve the analysis of molecular and can contribute to the deeper understanding of tumor behavior.3.The PAA-Azo was immobilized on the modified quartz plate by layer by layer self-assembly method,and the whole optical switch was prepared by combining cyclodextrin and azobenzene.Before the experiment of cell release,we use?-CD-RhB to simulate the effect of cell release,and under the 980nm irradiation,the part of exposure was patterned,which witnesses the feasibility of the cis-trans isomerization of azobenzene molecules.We use the specificity between anti-EpCAM and MCF-7 surface antigen to identify the breast cancer cells.Based on the purity of CTCs,to realize the CTCs capture and release under the mild NIR irradiation,the release efficiency is 90%.This technique can not only achieve the high efficiency of the cancer cells,but also can achieve the scatheless cancer cells.This recyclable chip achieves a sustainable development perspective,making the technology to close the clinical step.