Design of a photothermal antitumor experiment of functional nanomaterials
[Objective]The integration of education and scientific research is of great significance in promoting the construction of first-class disciplines and the development of high-level universities.During undergraduate or postgraduate training,combining scientific research and teaching is important in guiding students to discover and explore new knowledge.To improve the quality of student training and build first-class disciplines,gold nanorods(AuNRs)modified with cyclodextrin polyrotaxanes were taken as an example to design a comprehensive experiment to introduce a photothermal antitumor agent.[Methods]Background knowledge of tumors,nanoparticles,and photothermal therapies was introduced via videos,literature studies,and courseware before the experimental class.The mechanism of nanomaterial-based photothermal antitumor therapy was explained in the experimental class.The problem-based learning method was used to consolidate the knowledge of students.Students participating in the experiment were required to prepare AuNRs by the seed growth method from alkyl trimethyl ammonium bromide(CTAB)and sodium oleate.Then,the AuNRs were modified by pseudopolyrotaxane(PPR)with folic acid(FA)terminating at one end and thiolmethoxypoly(ethylene glycol)(mPEG-SH).The morphology and structure of the prepared nanomaterials were characterized by nuclear magnetic resonance spectroscopy(NMR),Fourier transform infrared spectroscopy(FT-IR),ultraviolet-visible spectroscopy(UV-Vis),and transmission electron microscopy(TEM).In vitro photothermal conversion experiments were conducted to evaluate the photothermal conversion properties of the prepared materials.HeLa and HepG2 cells were selected for the photothermal cytotoxicity experiment,and the uptake of AuNR-PPR-PEG-FITC by HeLa and HepG2 cells was observed by inverted fluorescence microscopy(IFM).[Results]The modified gold nanomaterials showed the characteristic absorption peaks of FA at 260,280,and 365 nm,indicating that the AuNRs were successfully modified.Subsequently,they were characterized by FT-IR.The modified gold nanomaterials had absorption peaks associated with the hydroxyls in cyclodextrin and benzene rings in FA at 3 000-3 100,1 450-1 650 and 650-900 nm,and the characterized peak around 1 700 nm was related to the carbonyl group vibration peak,indicating the successful combination of the ligand material FA and the AuNRs.The in vitro photothermal experiment showed that the temperature of AuNR-PPR-PEG solution under an 808 nm laser irradiation for 10 min could rise to more than 70℃.The AuNR-PPR-PEG material significantly reduced the cytotoxicity,and the cell survival rate was over 80%.In addition,the FA-modified nanomaterials showed good biocompatibility and tumor targeting.After the experiment,the students in each group collected and processed the relevant data with professional software to obtain graphs and tables.Then,the related experimental data were analyzed and discussed.Finally,students completed the experimental report in the form of scientific papers.[Conclusions]The presented experiment involves various related knowledge such as cancer therapy,chemical synthesis,instrument operation(NMR,UV,IFM,FT-IR,and TEM),cell experiments,and professional software,with good comprehensiveness.The practice has shown that the photothermal antitumor experiment integrated with teaching and research plays a significant role in developing students'comprehensive abilities,scientific research thinking,and innovative creativity.The combination of teaching and scientific research has achieved satisfactory performance in real applications.
combination of scientific research and teachingphotothermal antitumorgold nanorod