Preparation Of Indium Selenide Nanosheets And Zinc Ion Probes For Biomedical Applications

Nanomaterials used in biomedical field,such as inorganic nanomaterials and nucleic acid nanomaterials,are expected to provide a new framework for diagnosing,treating and preventing disease.Inorganic nanomaterials are widely used in biomolecular detection,imaging,cancer treatment and other fields owing to their high sensitivity,low cost and controllable shape and size.Nucleic acid nanomaterials are a new star in the field of nanomaterials,which provide new ideas for biosensing,ultra-sensitive biomolecular detection and disease treatment because of their high affinity,high selectivity,transmissibility,coding ability and designability.Due to the inefficient function and poor targeting,the further applications of nanomaterials are limited.Therefore,the development of new nanomaterials with unique functions is of great significance for biomedical research.Among them,inorganic photothermal nanomaterials represented by graphene and its derivatives,molybdenum disulfide?MoS₂?and black phosphorus?BP?are widely used in the photothermal therapy?PTT?of diseases.They're both two-dimensional van der Waals materials and are well-known as excellent semiconductors.Given their structural commonality,we speculate that the indium selenide,a semiconductor with similar structure,has similar photothermal properties and has potential applications in the field of PTT.On the other hand,the pathology of Alzheimer's disease is related to the destruction of the metal homeostasis mechanism in the body.The concentration and binding of metal ions in the body can effectively reflect the features of the disease.However,the low concentration and specific binding sites make it difficult to detect the concentrations of disease-related metal ions.Aptamer is a nucleic acid molecule that can specifically recognize and bind to a variety of small molecules and is commonly used in the design of various disease-related biosensing and therapeutic probes,which is an ideal choice for constructing metal ion probes.Thus,constructing the corresponding metal active ion probes based on aptamer will help to understand metal-related neuropathology and further reduce metal-related neurotoxicity.In this work we conducted two aspects of research.First,indium selenide,an analogue of graphene,was developed for photothermal therapy.Secondly,a nano-probe based on aptamer was constructed for the detection of metal active ions in Alzheimer's disease.The details are as follows:?1?A large quantities of 2D In₂Se₃ nanosheets were prepared through a solvent exfoliation technique.The In₂Se₃ nanosheets were obtained with lateral sizes of tens of nanometers to hundreds of nanometers and thickness of 2-17 layers.Moreover,these In₂Se₃ nanosheets exhibited an excellent near infrared?NIR?photothermal performance under an 808 nm laser irradiation.NIR photo-excitation of the In₂Se₃nanosheets in the presence of bacteria led to a significant antibacterial effect,suggesting that these nanosheets have great potential to be photothermal antibacterial agents.?2?A dual aptamer-conjugated molecular probe was designed to detect Zn²⁺around amyloid-beta?A??.The molecular probe could selectively target A?species and block the surrounding Zn²⁺due to the specific recognition capability of aptamers.With the binding of Zn²⁺,the fluorescence signal of this molecular probe was restored,thus allowing for Zn²⁺detection.Our approach can provide valuable information for studying the Zn²⁺-A?-related neuropathology and exhibits great potential for AD therapy.