Organic room-temperature phosphorescence (RTP) materials have garnered considerable attention in the fields of biosensing, optoelectronic devices, and anticounterfeiting because of their substantial Stokes shifts, tunable emission wavelengths, and prolonged lifetimes. These materials offer remarkable advantages for biological imaging applications by effectively reducing environmental autofluorescence and enhancing imaging resolution. Recently, host–guest systems have been employed as efficient approaches to fabricate pure-organic RTP materials for bioimaging, providing benefits such as controllable preparation and flexible modulation. Consequently, an increasing number of corresponding studies are being reported; however, a comprehensive systematic review is still lacking. Therefore, we summarize recent advances in the development of pure-organic RTP materials using host–guest systems with regard to bioimaging, including rigid matrices and sensitization. The challenge and potential of RTP for biological imaging are also proposed to promote the biomedical applications of organic RTP materials with excellent optical properties.

Background: The green globular body (GGB) of ferns is a special propagule induced in plant in vitro culture systems. Owing to its high proliferation efficiency, GGB is widely used in the in vitro propagation of important ornamental and medicinal ferns. In addition, propagation using GGB shows great development prospects in the conservation of rare or endangered ferns and the breeding of new fern varieties. However, due to the lack of systematic studies on GGB ontogenesis, the morphogenetic aspects of GGB during induction and differentiation remain unclear. Results: We characterized the response of five types of explants of Drynaria roosii to GGB inductive medium and further investigate morphological and anatomical changes of explants that developed GGBs. We found that the rhizome explants directly produced GGBs through cell proliferation of the shoot apical meristem and lateral meristem. The leaf and petiole explants produced GGBs indirectly through the proliferation of meristematic cells of somatic embryos derived from the epidermal cells of the explants. The root and gametophyte explants failed to produce GGB under our induction conditions. We further investigated the differentiation process of GGB. During GGB differentiation, shoot primordia and leaf primordia differentiate from meristematic cells on the epidermis, and the root primordia develop from an inner meristematic tissue with developing vascular tissue connecting all these primordia, which indicates the involvement of multiple organogenesis processes. Conclusions: Our results suggested that preexisting or reestablished meristematic cells were the direct source of GGB in D. roosii . Somatic embryogenesis and organogenesis were involved in GGB induction and differentiation, respectively. The comparison with other common propagules revealed that GGB in D. roosii was largely different from somatic embryos, callus, and protocorm or protocorm-like bodies.

Panax ginseng has been applied in traditional Chinese medicine for over 2000 years. It is still one of the most popular herbs in recent decades. The prescribed ginseng-containing medicines consist of protopanaxadiol and protopanaxatriol ginsenosides, which are the major constituents of the herb. Minor ginsenosides at low levels in the herb, such as Rg3 and Rg5 , have attracted more rising attention than the major ones. The existing approaches to prepare Rg3 and Rg5 usually rely on either steamed red ginseng as the source or chemical/enzymatic conversion of protopanaxadiol to the targets. It is still highly desirable to effectively achieve such minor components. In this paper, a method integrated extraction of protopanaxadiol and conversion of it to Rg3 and Rg5 has been proposed. Protopanaxadiol was extracted and simultaneously converted to Rg3 and Rg5 by d,l-tartaric acid. The targets were absorbed by resins on expanded bed adsorption chromatography and were then separated from other ginsenosides in different stages. Compared with conventional methods, the developed process has advantages in shortening time consumption and improving the conversion ratio of protopanaxadiol, which is promising in directly achieving Rg3 and Rg5 from P. ginseng.

St. John's wort has attracted particular attention because of its beneficial effects as an antidepressant, antiviral, and anticancer agent. A method for the combination of integrated expanded bed adsorption chromatography and countercurrent chromatography for the simultaneous extraction and purification of pseudohypericin and hypericin from the herb is presented in this paper. Firstly, the constituents were extracted and directly adsorbed by expanded bed adsorption chromatography under optimal conditions. The stepwise elution was then performed by expanded bed adsorption chromatography that enriched the targets with higher purities and recoveries compared to other methods. Secondly, the eluent fractions from expanded bed adsorption chromatography were further separated by two-step high-speed countercurrent chromatography. A two-step high-speed countercurrent chromatography method with a biphasic solvent system composed of n-hexane/ethyl acetate/methanol/water with a volume ratio of 1:2:1:2 was performed by stepwise changing the flow rate of the mobile phase. Consequently, 5.6 mg of pseudohypericin and 2.2 mg of hypericin with purities of 95.5 and 95.0%, respectively, were successfully obtained from 40 mg of crude sample.

Separation of polar alkaloids by countercurrent chromatography (CCC) is challengeable due to their close partition behaviors in solvent system. In this paper, a two-stage method for isolation of epiberberine, jatrorrhizine, palmatine, coptisine, and berberine from Rhizoma coptidis was presented. The first stage separation performed on CCC was based on the principle of reactive extraction. Trifluoroacetic acid was acted as a modulator to selectively react with alkaloids, which changed their partition coefficients in solvent system. Purified epiberberine and other partially separated targets were eluted by ammonium adjusted mobile phase. In the second stage, four alkaloids were purified in pH-zone-refining CCC mode. All the targets collected were over 97% pure determined by HPLC. The method developed demonstrates performing of reactive extraction on standard CCC as an option for separation of polar alkaloids from medicinal plants.

A new naphthalimide-based fluorescent turn-on probe (ANAg) was developed for quantitative detection of iodide in aqueous solution. It exhibited a low nanomolar detection limit and high selectivity over other potentially interfering anions and implied the potential for practical applications.

We have developed a fluorescent probe connecting boronate ester oxidation andin situcyclization together for the sensitive and selective detection of ONOO−.

Pure compounds extracted and purified from natural sources are crucial to lead discovery and drug screening. This study presents a novel two-dimensional hyphenation of expanded bed adsorption chromatography (EBAC) and high-speed countercurrent chromatography (HSCCC) for extraction and purification of target compounds from medicinal plants in a single step. The EBAC and HSCCC were hyphenated via a six-port injection valve as an interface. Fractionation of ingredients of Salvia miltiorrhiza and Rhizoma coptidis was performed on the hyphenated system to verify its efficacy. Two compounds were harvested from Salvia miltiorrhiza, one was 52.9 mg of salvianolic acid B with an over 95% purity and the other was 2.1 mg of rosmarinic acid with a 74% purity. Another two components were purified from Rhizoma coptidis, one was 4.6 mg of coptisine with a 98% purity and one was 4.1 mg of berberine with a 82% purity. The processing time was nearly 50% that of the multistep method. The results indicate that the present method is a rapid and green way to harvest targets from medicinal plants in a single step.

SP1 protein as a new type of biological nanopore is described and is utilized to distinguish single-stranded DNA at the single-molecule level. Using the SP1 nanopore to investigate single molecule detection broadens the existing research areas of pore-forming biomaterials from unsymmetrical biological nanopores to symmetrical biological nanopores. This novel nanopore could provide a good candidate for single-molecule detection and characterization of biomaterial applications.

Porphyrin covalently bonded to graphene oxide (Por–GO) was used as a photoactive unit, and resulted in an enhanced photoresponse, when in combination with gold nanoparticles (GNP) as a light harvesting unit, due to its plasmon resonance absorption effect. Photocurrent monitoring of the interaction between the surface-modified Por–GO with adenosine compounds was demonstrated.

The reversible electrochemical modulation of fluorescence and selective sensing of ascorbic acid has been achieved using a DCIP-CA-CdTe QD system. Ascorbic acid could be detected over a linear range from 2.33 μM to 56.49 μM, with a detection limit of 0.50 μM.

A dual-function chemosensor for Hg2+ and Zn2+ ions, inspired by the green fluorescent protein (GFP) chromophore, was designed and synthesized, which could specifically recognize Zn2+ through an "OFF–ON" fluorescence mechanism due to the restriction of the free rotation of the aryl–alkene bond, whilst also producing a selective visible colorimetric response from yellow to pink with Hg2+ ions. The response upon exposure to Zn2+ and Hg2+ is instantaneous, and the detect limits of Zn2+ and Hg2+ are 2.18×10−8 M and 4.91×10−7 M respectively.

Quantum dots (QDs) have been widely used for fluorescent imaging in cells. In particular, surface functionalized QDs are of interest, since they possess the ability to recognize and detect the analytes in the surrounding nanoscale environment based on electron and hole transfer between the analytes and the QDs. Here we demonstrate that fluorescence enhancement/quenching in QDs can be switched by electrochemically modulating electron transfer between attached molecules and QDs. For this purpose, a number of redox-active coenzyme Q (CoQ) disulfide derivatives [CoQC(n)S](2) were synthesized with different alkyl chain lengths (n=1, 5, and 10). The system supremely sensitive to NADH (nicotinamide adenine dinucleotide) and superoxide radical (O(2)(.)(-)), and represents a biomimetic electron-transfer system, modeling part of the mitochondrial respiratory chain. The results of our in situ fluorescence spectroelectrochemical study demonstrate that the reduced state of [CoQC(n)S](2) significantly enhanced the fluorescence intensity of CdTe/ZnS QDs, while the oxidized state of the CoQ conjugates quench the fluorescence to varying degrees. Fluorescence imaging of cells loaded with the conjugate QD-[CoQC(n)S](2) displayed strikingly differences in the fluorescence depending on the redox state of the capping layer, thus introducing a handle for evaluating the status of the cellular redox potential status. Moreover, an MTT assay (MTT=3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) proved that the cytotoxicity of QDs was significantly reduced after immobilization by CoQ derivatives. Those unique features make CoQ derivatived QDs as a promising probe to image redox coenzyme function in vitro and in vivo.

We demonstrate that the coupling system of negatively capped CdSe/ZnS QDs with an oxidized Cytochrome c (Cyt c) is capable of the fluorescent imaging of a superoxide radical (O(2)˙⁻) with high sensitivity and specificity in living cells, without interference from other Reactive Oxygen Species (ROS) or relevant intracellular components.

Here, we report the reversible interconversion between NADH and NAD(+) at a low overpotential, which is in part mediated by ubiquinone embedded in a biomimetic membrane to mimic the initial stages of respiration. This system can be used as a platform to examine biologically relevant electroactive molecules embedded in a natural membrane environment and provide new insights into the mechanism of biological redox cycling.

A green fluorescent protein chromophore inspired chemosenor for Zn(2+) was designed and synthesized. A Zn(2+) specific fluorescence enhancement was observed due to restricted rotation between the 1,10-phenanthroline and imidazolone moieties.

The translocation time of poly(dT)(45) through an α-hemolysin pore was reduced in the presence of a DNA-binding Fab fragment. The Fab acts as a rudder to steer the DNA into the pore.

We demonstrate that the continuous real-time monitoring of the growth and surface oxidation process of single Cu nanoparticles (NPs) on an indium-tin oxide (ITO) substrate by dark-field microscopy (DFM) and plasmon resonance Rayleigh scattering (PRRS) spectroscopy is possible.

A new sensing molecule 8-hydroxyquinoline ferrocenoate (Fc-Q) which combines ferrocene and 8-hydroxyquinoline moieties was synthesized and applied as a multi-channel sensor for the detection of Hg2+ ion. Fc-Q can coordinate with Hg2+ to give colorimetric, fluorescent and electrochemical responses. Upon complexation with Hg2+ ion, the characteristic absorption peak is red-shifted (Δλ=45nm), the fluorescent intensity is quenched at 303nm, and the oxidation peak is cathodic shifted (ΔE1/2=−149mV). Quantitatively analyzed Hg2+ ions at the range of ppb level could be achieved by electrochemical response. For the practical application of sensing Hg2+ in real world water, Fc-Q modified screen-printed carbon electrodes were obtained for facile, sensitive, and on-site analysis of Hg2+.

SmallVolume 7, Issue 12 p. 1624-1628 Communication Ultrasensitive Determination of Cysteine Based on the Photocurrent of Nafion-Functionalized CdS–MV Quantum Dots on an ITO Electrode Yi-Tao Long, Corresponding Author Yi-Tao Long [email protected] Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaShanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. China.Search for more papers by this authorCong Kong, Cong Kong Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaSearch for more papers by this authorDa-Wei Li, Da-Wei Li Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaSearch for more papers by this authorYang Li, Yang Li Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaSearch for more papers by this authorSomenath Chowdhury, Somenath Chowdhury Department of Chemistry, Yale University, New Haven, CT 06520–8107, USASearch for more papers by this authorHe Tian, He Tian Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaSearch for more papers by this author Yi-Tao Long, Corresponding Author Yi-Tao Long [email protected] Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaShanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. China.Search for more papers by this authorCong Kong, Cong Kong Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaSearch for more papers by this authorDa-Wei Li, Da-Wei Li Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaSearch for more papers by this authorYang Li, Yang Li Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaSearch for more papers by this authorSomenath Chowdhury, Somenath Chowdhury Department of Chemistry, Yale University, New Haven, CT 06520–8107, USASearch for more papers by this authorHe Tian, He Tian Shanghai Key Laboratory of Functional Materials Chemistry & Department of Chemistry, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P.R. ChinaSearch for more papers by this author First published: 04 May 2011 https://doi.org/10.1002/smll.201100427Citations: 138Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Graphical Abstract An ultrasensitive cysteine sensor is prepared by using a Nafion assembly of a CdS quantum dot–methyl viologen complex on a conductive ITO surface. It is effective in the readout of the photoelectrochemical response to cysteine with high sensitivity, good selectivity, and fast response. Citing Literature Supporting Information Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Filename Description smll_201100427_sm_suppl.pdf999 KB suppl Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article. Volume7, Issue12June 20, 2011Pages 1624-1628 RelatedInformation