Unusually Sensitive Solid State Emissive 1,8-naphthalimide for Detection of Acid Vapors in Turn-off Mode and Base Vapors in Turn-on Mode.

A 4-amino-1,8-naphthalimide containing tetramethylpiperidine in N-position was synthesized. The prepared 1,8-naphthalimide was found to possess bright yellow-green fluorescence in a solid state, which could be switched-off in the presence of acid vapors and then switched-on after exposure on base vapors. The observed fluorescence quenching or enhancement, respectively, was more than 10-fold.

A Tutorial Review on the Fluorescent Probes as a Molecular Logic Circuit-Digital Comparator.

The rapid progress in the field of fluorescent probes and fluorescent sensing material extended this research area toward more complex molecular logic gates capable of carrying out a variety of sensing functions simultaneously. These molecules are able to calculate a composite result in which the analysis is not performed by a man but by the molecular device itself. Since the first report by de Silva of AND molecular logic gate, all possible logic gates have been achieved at the molecular level, and currently, utilization of more complicated molecular logic circuits is a major task in this field.

Design and Synthesis of a Novel ICT Bichromophoric pH Sensing System Based on 1,8-Naphthalimide Fluorophores as a Two-Input Logic Gate and Its Antibacterial Evaluation.

The synthesis, sensor activity, and logic behavior of a novel 4-iminoamido-1,8-naphthalimide bichromophoric system based on a "" architecture with ICT chemosensing properties is reported. The synthesized compound showed good colorimetric and fluorescence signaling properties as a function of pH and proved itself as a promising probe for the rapid detection of pH in an aqueous solution and base vapors in a solid state. The novel dyad is able to work as a two-input logic gate with chemical inputs H (Input 1) and HO (Input 2) executing INHIBIT logic gate.

Fluorescent Probes as a Tool in Diagnostic and Drug Delivery Systems.

Over the last few years, the development of fluorescent probes has received considerable attention. Fluorescence signaling allows noninvasive and harmless real-time imaging with great spectral resolution in living objects, which is extremely useful for modern biomedical applications. This review presents the basic photophysical principles and strategies for the rational design of fluorescent probes as visualization agents in medical diagnosis and drug delivery systems.

A Novel Fluorescent Probe for Determination of pH and Viscosity Based on a Highly Water-Soluble 1,8-Naphthalimide Rotor.

A novel highly water-soluble 1,8-naphthalimide with pH and viscosity-sensing fluorescence was synthesized and investigated. The synthesized compound was designed as a molecular device in which a molecular rotor and molecular "off-on" switcher were integrated. In order to obtain a TICT driven molecular motion at C-4 position of the 1,8-naphthalimide fluorophore, a 4-methylpiperazinyl fragment was introduced.

A Highly Water-Soluble and Solid State Emissive 1,8-Naphthalimide as a Fluorescent PET Probe for Determination of pHs, Acid/Base Vapors, and Water Content in Organic Solvents.

A new highly water-soluble 1,8-naphthalimide fluorophore designed on the "" model has been synthesized. Due to the unusually high solubility in water, the novel compound proved to be a selective PET-based probe for the determination of pHs in aqueous solutions and rapid detection of water content in organic solvents. Based on the pH dependence of the probe and its high water solubility, the INH logic gate was achieved using NaOH and water as chemical inputs, where NaOH is the disabler and the water is an enabler.

Low Molecular Weight Probe for Selective Sensing of PH and Cu Working as Three INHIBIT Based Digital Comparator.

A novel simple molecular chemosensor 2 was synthesized and examined for pH, cations and anions detection. At pH values higher than 10, probe 2 switches on a green emission where the excited state intramolecular proton transfer (ESIPT) is ceased. Also, the probe absorption spectrum shows a clear pH dependence, and the probe aqueous solution (ethanol/water = 1:2, borate buffer) responds selectively and sensitively through its fluorescence spectrum to the presence of Cu.

A chemosensoring molecular lab for various analytes and its ability to execute a molecular logical digital comparator.

We reported here the unique ability of a Rhodamine 6G-based probe (3) to detect discriminately several targets, including H, HO, Cu, Hg, Fe, Co, Cd, Zn, Sn, Ni, Al, Pb, Ceand Ag, by unambiguously colorimetric and fluorimetric outcomes. In aqueous solutions, the presence of proton induced the ring-opening of rhodamine moiety but the presence of hydroxide induced the conversion of 2-hydroxyphenyl hydrazone moiety from the non-fluorescent benzenoid form into the fluorescent quinoid form. The probe could to distinguish between different cations in DMF and to work like an artificial tongue at molecular level.

A smart chemosensor: Discriminative multidetection and various logic operations in aqueous solution at biological pH.

A novel rhodamine-pyrazole based molecular probe was designed and easily synthesized. The probe could to detect several analytes in aqueous solution at biological pH (HEPES, pH = 7.2).

Synthesis of a single 1,8-naphthalimide fluorophore as a molecular logic lab for simultaneously detecting of Fe, Hg and Cu.

A novel fluorescence sensing 1,8-naphthalimide fluorophore is synthesized and investigated. The novel probe comprising two different binding moieties is capable to detect selectively Fe over the other representative metal ions as well as a combination of biologically important cations such as Fe, Cu and Hg in the physiological range without an interfering effect of the pHs. Due to the remarkable fluorescence changes in the presence of Fe, Hg and Cu ions, INH and AND logic gates are executed and the system is able to act as a single output combinatorial logic circuit with three chemical inputs.

Synthesis, fluorescence-sensing and molecular logic of two water-soluble 1,8-naphthalimides.

Two novel highly water-soluble fluorescence sensing 1,8-naphthalimides are synthesized and investigated. The novel compounds are designed on the "fluorophore-receptor-spacer-receptor" model as a molecular fluorescence probe for determination of cations and anions in 100% aqueous media. The novel probes comprising N-imide and N-phenylpiperazine or morpholine substituents are capable to operate simultaneously via ICT and PET signaling mechanism as a function of pH and to recognize selectively Cu and Hg over the other representative metal ions.

Novel PAMAM Dendron as a Bichromophoric Probe Based on Rhodamine 6G and 1,8-Naphthalimide.

A novel PAMAM dendron designed as a wavelength-shifting bichromophore with 1,8-naphthalimide energy "donor" capable of absorbing light and efficiently transferring the energy to a focal Rhodamine 6G "acceptor" was synthesized and investigated. Moreover, the system was configured on the "fluorophore-spacer-receptor" format. Thus, the distinguishing features of FRET systems were successfully combined with the properties of photoinduced electron transfer and classical ring-opening sensor systems.

Novel nanosized water soluble fluorescent micelles with embedded perylene diimide fluorophores for potential biomedical applications: cell permeability, localization and cytotoxicity.

Novel biocompatible water-soluble fluorescent micelles with embedded perylene diimides (PDI) for intracellular applications have been prepared by self assembling of amphiphilic poly(vinyl alcohol)-b-poly(acrylonitrile) (PVA-b-PAN) copolymers in the presence of synthesized fluorophores. Amphiphilic PVA-b-PAN copolymers were obtained by selective hydrolysis of well-defined poly(vinyl acetate)-b-poly(acrylonitrile) (PVAc-b-PAN) copolymer. The preparation of the novel fluorescence micelles consisting of PVA hydrophilic shell and PAN hydrophobic core with incorporated PDI fluorophores has been confirmed by DLS and TEM analysis.

Synthesis and sensor activity of a PET-based 1,8-naphthalimide Probe for Zn(2+) and pH determination.

A novel blue-emitting 1,8-naphthalimide fluorophore designed as a molecular PET-based probe for determination of pH and detection of transition metal ions in the environment was successfully synthesized. Novel compound was configured on the "fluorophore-spacer-receptor" format. Due to the tertiary amine receptor the novel system showed "off-on" switching properties under the transition from alkaline to acid media (FE = 3.

A novel pH sensitive water soluble fluorescent nanomicellar sensor for potential biomedical applications.

Herein we report on the synthesis and sensor activity of a novel pH sensitive probe designed as highly water-soluble fluorescent micelles by grafting of 1,8-naphthalimide-rhodamine bichromophoric FRET system (RNI) to the PMMA block of a well-defined amphiphilic diblock copolymer-poly(methyl methacrylate)-b-poly(methacrylic acid) (PMMA48-b-PMAA27). The RNI-PMMA48-b-PMAA27 adduct is capable of self-assembling into micelles with a hydrophobic PMMA core, containing the anchored fluorescent probe, and a hydrophilic shell composed of PMAA block. Novel fluorescent micelles are able to serve as a highly sensitive pH probe in water and to internalize successfully HeLa and HEK cells.

Design, synthesis and pH sensing properties of novel PAMAM light-harvesting dendrons based on rhodamine 6G and 1,8-naphthalimide.

Herein we report on the design, divergent synthesis and photophysical behavior of novel PAMAM light-harvesting dendrons from first and second generation. The surface of novel compounds is labeled with 4-alkylamino-1,8-naphthalimide yellow-green emitting "donor" fluorophores capable of absorbing light and efficiently transferring the energy to a single rhodamine "acceptor" dye. Due to the pH dependent rhodamine absorption the novel systems show "off-on" switching energy transfer mechanism from alkaline to acid media.

Sensor activity and logic behaviour of PET based dihydroimidazonaphthalimide diester.

An ester terminated dihydroimidazonaphthalimide as multi-functional logic device is presented. Due to the optical changes as a function of pH this simple molecule is able to act as a molecular pH metre, a digital comparator and a half-adder. It was demonstrated that the dihydroimidazonaphthalimide comparator could be used as a fundamental element of an optical device for control of pH windows.

Design, synthesis and photostability of novel 1,8-naphthalimide PAMAM light-harvesting dendrons.

This paper reports on the divergent synthesis, photophysical properties and photodegradation of novel PAMAM dendrons, core and peripherally functionalized with 1,8-naphthalimide fluorophores. The novel compounds were configured as light-harvesting antennae where the system surface is labeled with blue emitting 4-allyloxy-1,8-naphthalimide "donor" fluorophores capable of absorbing light and efficiently transferring the energy to a single yellow-green emitting 4-alkylamino-1,8-naphthalimide "acceptor" dye. The focal 1,8-naphthalimide fluorophores in the antennae were modified with a HALS fragment (2,2,6,6-tetramethylpiperidine or 1,2,2,6,6-pentamethylpiperidine) with a view to improve their photostability.

Design and synthesis of highly photostable yellow-green emitting 1,8-naphthalimides as fluorescent sensors for metal cations and protons.

Two highly photostable yellow-green emitting 1,8-naphthalimides 5 and 6, containing both N-linked hindered amine moiety and a secondary or tertiary cation receptor, were synthesized for the first time. Novel compounds were configured as "fluorophore-spacer-receptor" systems based on photoinduced electron transfer. Photophysical characteristics of the dyes were investigated in DMF and water/DMF (4:1, v/v) solution.