Design,Assembly And Sensing Applications Of Novel Fluorescent Molecules

The luminescent materials,have attracted increasing attention over the past decades,especially in the area of self-assembly and sensing.Herein,we mainly studied the design,synthesis,assembly and sensing applications of two types of modified fluorescent dyes.One is the controlled assembly of fluorescent molecules based on naphthalimide and their application in controlled fluoride ion sensing.The other is based on the design and synthesis of methylene blue fluorescent molecules of hydrogen peroxide-sensitized,and realizes its sensing of H2O2 in cells.The details are as follows:1)Self-assembly Properties of Fluorescent Organic Gel comprised of Naphthalimide and Alkyne unitsA fluorescent gelator NDS containg bischolesterole and butyne-containing units was designed and synthesized.Found it in methylene chloride and chloroform self-assembly in the formation of the dry gel has a large-scale ordered honeycomb structure,and in chloroform and water to mix proportion of different system,the gel factors also can be formed within the high W/O emulsion phase gel.The pore size of honeycomb structure can be controlled effectively by using water content and its assembly mechanism is studied in detail.Further studies have shown that the presence of water molecules can effectively promote the J aggregation between naphthyl imide fluorescence agglomeration and acetylene,and improve the mechanical properties of gel emulsion.2)Optical properties of naphthalimide-based gel and its selective sensing toward F~-A novel fluorescent organogelator NSS comprised of C=N and N-NH units was designed and characterized.By light irradiation,NSS could undergo trans to cis transformation both in solution and gel state,which was accompanied by dramatic color,fluorescence intensity,and emission color changes,indicating the photochromic property of NSS.Both of the gels in E-isomeric and Z-isomeric forms could selectively response to fluoride anion among tested anions.Further study presented that the two isomers displayed different signal outputs and binding mechanisms toward fluoride anion.Especially,the organogel of NSS in the E-isomeric form showed selective,visual,and reversible sensing for fluoride anion.Beside theabove functions,the organogel could also response to ultrasound and heating stimuli,thus endowing theorganogel with multi-stimuli responsive properties.3)Development and application of methylene blue-based fluorescent probe tward H2O2Different from the visible fluorescent molecules,Based on methylene blue fluorophore,designed and synthesized a noval near-infrared,highly sensitive and selective fluorescent probe for the detection of H2O2.Upon the addition of H2O2,the fluorescence intenisty of NDH enhanced by hundreds of times.In addition,we also showed that the probe can be used to detect exogenous H2O2 in He La cell model.