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Electronic or nuclear spins represent promising candidates of qubits for applications in quantum information technologies and spintronic devices. However, it remains a challenge to achieve scalable and spatially defined organization of a large number of spins as qubits, which is essential in the feasible fabrication of quantum circuits. We report a strategy of block copolymer self‐assembly to organize molecular spins as qubits across molecular to micro‐/nano‐scales in polymeric films of organic luminescent radicals centered in star‐like block copolymers. We have achieved not only scalable and spatially defined organization of the molecular spins in polymeric films with long‐range periodic ordering but also controllable spin‐lattice relaxation dynamics and spin coherence lifetimes that can be finely tuned by the domain sizes and rigidities of the polymeric matrices. [ABSTRACT FROM AUTHOR]

This article discusses a study on the role of autotoxin-degrading bacteria in alleviating replant problems in tobacco crops. The researchers found that Pseudomonas and Burkholderia species were more abundant in soil with autotoxin-degrading bacteria, and they isolated two strains of bacteria that efficiently degrade vanillin, a component of autotoxin. Inoculating these bacteria into vanillin-modified soil improved the growth of tobacco seedlings. The study suggests that autotoxin-degrading bacteria have the potential to promote soil health and crop growth. [Extracted from the article]

Molecular switches that reversibly change their structures and physical properties are important for applications such as sensing and information processing at molecular scales. In order to avoid the intermolecular aggregation that is often detrimental to the stimuli‐responses of molecular switches, previous studies of molecular switches have been often conducted in dilute solutions which are difficult for applications in solid‐state devices. Here we report molecular design and synthesis that integrates anthraquinodimethane as molecular switching units into polymers with amenable processibility in solid states. Optical and electron spin resonance characterizations indicate that the four‐arm polymers of poly(ϵ‐caprolactone) or poly(D,L‐lactide) tethered from anthraquinodimethane slow down the dynamics of the conformational switching between the folded and the twisted conformations, enhance the photoluminescence in solid states and impart materials with a small energy gap from singlet ground state to thermally accessible triplet state. [ABSTRACT FROM AUTHOR]

Control of the intermolecular aggregation of organic π‐conjugated molecules as chromophores is crucial for tuning their physical properties such as light absorption/emission, and energy and charge transfer. Lots of advances have been achieved in control of intermolecular aggregation of organic chromophores in solid states where an indefinitely large number of molecules are involved. However, much less understanding has been gained at a mesoscale of aggregates formed by well‐defined organization of a deterministic number of chromophores, which has been realized in natural photosynthetic systems but still remains rare in manmade materials. Here, we report both the kinetic and the thermodynamic control of the supramolecular aggregation of a near‐infrared cyanine dye, PPcy, and its derivatives confined in colloidal nanoparticles stabilized by surfactants in aqueous media. Our results demonstrate that both the aggregation number, the aggregation state and the optical properties of the PPcy chromophores are controllable through optimization of the alkyl and polymer chains tethered from PPcy, the effective concentration of the chromophore inside each particle, and the surfactants utilized to stabilize the colloids in water. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The discovery of fluorescent proteins has inspired a lot of interest to develop synthetic polymers with similar structures and functionalities. In this review article, we first give a brief introduction for the discovery, the structural characteristics and optical properties of fluorescent proteins, using green fluorescent protein (GFP) as an example. In the body part of article, we summarize recent advances in molecular design, synthesis and processing of bioinspired fluorescent polymers with unique optical properties such as high fluorescence quantum yield and robust photostability. Several major approaches highlighted here include the recombination of organic chromophores and proteins, and synthesis of the bioinspired polymers containing a single fluorophore in each polymer chain. The optical properties and applications of some representative bioinspired fluorescent polymers in bioimaging, sensing and imaging‐guided therapy are also elucidated. [ABSTRACT FROM AUTHOR]

The sensitive, safe, and portable detection of food spoilage is becoming unprecedentedly important because it is closely related to the public health and economic development, particularly given the globalization of food supply chain. However, the existing approaches for food monitoring are still limited to meet these requirements. To address this challenge, much research has been done to develop an ideal food sensor that can indicate food quality in real‐time in a sensitive and reliable way. So far, many sensors such as time–temperature indicators, smart trademarks, colorimetric tags, electronic noses, and electronic tongues, have been developed and even commercialized. In this feature article, the recent progress of food sensors based on functional polymers, including the molecular design of polymer structures, sensing mechanisms, and relevant processing techniques to fabricate a variety of food sensor devices is reviewed. [ABSTRACT FROM AUTHOR]

Melt ponds occupy a large fraction of the Arctic sea ice surface during spring and summer. The fraction and distribution of melt ponds have considerable impacts on Arctic climate and ecosystem by reducing the albedo. There is an urgency to obtain improved accuracy and a wider coverage of melt pond fraction (MPF) data for studying these processes. MPF information has generally been acquired from optical imagery. Conventional MPF algorithms based on high‐resolution optical sensors have treated melt ponds as features with constant reflectance; however, the spectral reflectance of ponds can vary greatly, even at a local scale. Here we use Sentinel‐2 imagery to demonstrate those previous algorithms assuming fixed melt pond‐reflectance greatly underestimate MPF. We propose a new algorithm (“LinearPolar”) based on the polar coordinate transformation that treats melt ponds as variable‐reflectance features and calculates MPF across the vector between melt pond and bare ice axes. The angular coordinate θ of the polar coordinate system, which is only associated with pond fraction rather than reflectance, is used to determinate MPF. By comparing the new algorithm and previous methods with IceBridge optical imagery data, across a variety of Sentinel‐2 images with melt ponds at various stages of development, we show that the RMSE value of the LinearPolar algorithm is about 30% lower than for the previous algorithms. Moreover, based on a sensitivity test, the new algorithm is also less sensitive to the subjective threshold for melt pond reflectance than previous algorithms.Plain Language Summary: Melt ponds are pools of open water that form on the sea ice surface in the Arctic in summer months. Sea ice covered by melt ponds absorbs more solar heat than solid ice which speeds up the rate of sea ice melt. To study this process, we need melt pond coverage data that are generally obtained from satellite observations. There are several methods to calculate the melt pond fraction from high‐resolution optical satellite imagery but these methods assume that melt ponds have constant optical properties, which is not true. In this study, we show that these existing methods significantly underestimate melt pond fraction. To address this problem, we present a new method that treats melt ponds as features having variable optical properties. Images of sea ice from aircraft are used to assess the new algorithm and two previous methods, demonstrating that the new algorithm has higher accuracy and precision.Key Points: Sentinel‐2 and IceBridge imagery are used to show that algorithms assuming fixed melt pond‐reflectance largely underestimate melt pond fractionA new algorithm based on the polar coordinate transformation that treats melt ponds as variable‐reflectance has been developedThe accuracy and precision of the new Sentinel‐2 algorithm, assessed with IceBridge DMS imagery, are higher than previous algorithms [ABSTRACT FROM AUTHOR]

Paddy fields are valuable agricultural land resources in the Three Gorges Reservoir area of China but have been threatened by the expansion and intensification of human activities over recent decades. How paddy fields evolve under human disturbances remains poorly understood, which is critical for land use planning to compromise agricultural production and ecosystem conservation as limited land resource is available. In this study, the spatial and temporal patterns of change in paddy fields were depicted and principal driving forces were explained. Mapping of paddy fields with LANDSAT satellite images reveals a constant declining trend by 14.3% in the period 1990–2015. The gross loss area is 903.3 km2, with an annual average decreasing rate being 36.1 km2·yr−1. The transformation matrix between paddy fields and other land uses explicitly explains the impact trajectories of multiple human activities. Specifically, 39.6% (408.1 km2) of the gross loss was converted to built‐up lands, reflecting town translocation and human resettlement (involuntary population migration) proposed by construction of the Three Gorges Dam, as well as urbanization, industrial development and infrastructure expansion along with economic development. The area converted to forests accounts for 26.4% (238.2 km2), which could be ascribed to land abandonment and the reforestation campaign. 23.1% (208.7 km2) was converted to dry croplands by shifts in farmers' preference on crop selection following socioeconomic changes (e.g., voluntary rural population migration, land use policy adjustment, commercial farming enterprises expansion). 46.5 km2 was converted to water bodies, indicating the effect of impoundment of the Three Gorges Reservoir. [ABSTRACT FROM AUTHOR]

Hilly areas necessitate a field road vehicle with high automation to reduce the amount of labor required to transport agricultural products and to increase productivity. In this paper, an adaptive integrated navigation method (combining global navigation satellite system (GNSS) and inertial navigation system (INS)) and path tracking control strategy of field road vehicles are studied in view of the problems of frequent GNSS outages and high automatic control precision requirement in hilly areas. An indirect Kalman filter (KF) is designed for the GNSS/INS information fusion. A modified method for calculating the KF adaptive factor is proposed to effectively suppress the divergence of the KF and a threshold judgement method to abandon the abnormal GNSS measurement is proposed to deal with GNSS interruptions. To achieve automated driving, a five-layer fuzzy neural network controller, which takes the lateral deviation, heading deviation, and path curvature as input and the steering angle as output, is proposed to control vehicle autonomous tracking of the navigation trajectory accurately. The proposed system was evaluated through simulation and experimental tests on a field road. The simulation results showed that the adjusted KF fusion algorithm can effectively reduce the deviation of a single GNSS measurement and improve the overall accuracy. The test results showed the maximum deviation of the actual travel trajectory from the expected trajectory of the vehicle in the horizontal direction was 12.2 cm and the average deviation was 5.3 cm. During GNSS outages due to obstacles, the maximum deviation in the horizontal direction was 12.7 cm and the average deviation was 6.1 cm. The results show that the designed GNSS/INS integrated navigation system and trajectory tracking control strategy can control a vehicle automatically while driving along a field road in a hilly area. [ABSTRACT FROM AUTHOR]

Wide‐bandgap π‐conjugated donor‐acceptor (D‐A) alternating copolymers consisting of benzo[1,2‐c:4,5‐c']dithiophene‐4,8‐dione (BDTD) as the electron‐accepting building block have demonstrated outstanding performances in organic bulk heterojunction (BHJ) solar cell devices. But the synthesis of these polymers has been largely limited to conventional polymerization techniques, particularly Stille‐coupling based polycondensations, which often involve tedious preactivation of C‐H bonds using highly flammable reagents such as butyl lithium and highly toxic reagents such as trialkyl tin chlorides. Herein, we report a "greener" synthetic route of direct arylation polymerization to a series of wide bandgap D‐A copolymers with a common acceptor building block of BDTD. The structure–property relationship in these polymers is characterized. We also present the device performances of these polymers in both thin‐film field‐effect transistors and organic BHJ solar cells involving the BDTD‐based polymers as the electron donors and fullerene derivatives as the electron acceptors. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2554–2564 Three donor‐acceptor polymers containing benzo[1,2‐c:4,5‐c']dithiophene‐4,8‐dione (BDTD) are synthesized by direct arylation polymerization and their structure and optical properties are studied. Polymer containing quarterthiophene as the donor (P3) shows aggregation in solution state and BJH organic solar cells fabricated using P3 and PC71BM show power conversion efficiencies up to 3.5%. [ABSTRACT FROM AUTHOR]

Abstract: A base‐promoted and metal‐/oxidant‐free one‐pot three‐component tandem annulation of amidines, aryl/alkyl isothiocyanates, and α‐bromoesters/ketones to 2,4,5‐trisubstituted thiazoles is described. This operationally simple protocol involves a base‐promoted C−N bond cleavage of amidines and features readily available starting materials, excellent functional group tolerance, and high step‐economy. It leads to the preparation of 2,4,5‐trisubstituted thiazoles efficiently and has potential applications in the field of drug screening and modification. [ABSTRACT FROM AUTHOR]

Abstract: A near‐infrared (NIR) fluorescent donor/acceptor (D/A) nanoplatform based on Förster resonance energy transfer is important for applications such as deep‐tissue bioimaging and sensing. However, previously reported D/A nanoparticles (NPs) often show limitations such as aggregation‐induced fluorescence quenching and poor interfacial compatibility that reduces the efficiency of the energy transfer and also leads to leaching of the small molecular fluorophores from the NP matrix. Here highly NIR‐fluorescent D/A NPs with a fluorescence quantum yield as high as 46% in the NIR region (700–850 nm) and robust optical stability are reported. The hydrophobic core of each NP is composed of donor and acceptor moieties both of which are tethered with polycaprolactone (PCL), while the hydrophilic corona is composed of poly[oligo(ethylene glycol) methyl ether methacrylate] to offer colloidal stability and “stealthy” effect in aqueous media. The PCL matrix in each colloidal NP not only offers biocompatibility and biodegradability but also minimizes the aggregation‐caused fluorescence quenching of D/A chromophores and prevents the leakage of the NIR fluorophores from the NPs. In vivo imaging using these NIR NPs in live mice shows contrast‐enhanced imaging capability and efficient tumor‐targeting through enhanced permeability and retention effect. [ABSTRACT FROM AUTHOR]

Development of new, effective, and patient-friendly adhesives for biological tissues is important for medical and surgical practices such as bleeding control and organ repairing. While some commercially available silica nanoparticles such as LUDOX SM-30 have shown adhesive properties for biological tissues, the role of inorganic base present in the adhesive properties of the silica nanoparticles has not been examined. Moreover, it remained unclear how the size and the shape of silica nanoparticles affect the adhesion properties. To address these questions, synthesis and characterization of a series of uniform silica nanostructures with different sizes and shapes is carried out. Unexpectedly, none of the synthesized silica nanostructures without additional inorganic base shows adhesion properties against liver tissues. Such surprising phenomena motivate to examine other factors in the commercial silica nanoparticles as tissue adhesives, and reach a conclusion that the inorganic base plays a key role in the adhesion properties. It is believed that this study answers the important question whether silica nanoparticles can act as biological adhesives or not. The conclusion also gives a lesson to other scientists and engineers in design and exploration of new biological adhesives. [ABSTRACT FROM AUTHOR]

ABSTRACT Direct arylation polymerization between derivatives of dibromodiketopyrrolopyrrole (DPP) and thienoisoindigo (TIIG) resulted in two π-conjugated copolymers with average molecular weights up to 24.0 kDa and bandgaps as low as 0.8 eV. The structural analysis of the obtained two polymers revealed well-defined alternating conjugation backbones without obvious structural defects. The introduction of hexyl-group in the β-position of thiophene rings in the DPP units not only reduces the bandgap of conjugated polymer compared to a similar polymer containing bare-thiophene flanked DPP but also affects polymer morphology in thin films. P-type charge-transport characteristics were observed for two polymers in organic field-effect transistors with comparable hole mobilities. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3205-3213 [ABSTRACT FROM AUTHOR]

ABSTRACT: Direct arylation polymerization (DAP) enabled facile synthesis of a narrow bandgap donor-acceptor conjugated polymer (PDFBT-Th4) composed of alternating 5,6-difluoro-2,1,3-benzothiadiazole and alkyl-quaternarythiophene. The optimized reaction condition of DAP catalyzed with Pd(OAc)2/( o-MeOPh)3P/PivOH/K2CO3 in o-xylene led to the target polymer with a number-average molecular weight ( Mn) of 14.6 kDa without noticeable homocoupling or β-branching defects. UV-vis absorption spectra of PDFBT-Th4 indicate strong interchain aggregation in films. While the C-H selectivity and the alternating polymer structure of PDFBT-Th4 synthesized via DAP are comparable to those of the same type polymers synthesized via Stille coupling, the batch of PDFBT-Th4 synthesized via optimal DAP, despite its lower Mn, showed higher hole mobility in field effect transistors and larger power conversion efficiency in organic solar cell devices. These results further demonstrate the promising potential of DAP for efficient synthesis of high-performance D-A conjugated polymers for broad optoelectronic applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1869-1879 [ABSTRACT FROM AUTHOR]

Colloidal nanoparticles (NPs) containing near-infrared-fluorescent J-aggregates (JAGGs) of pyrrolopyrrole cyanines (PPcys) stabilized by amphiphilic block co-polymers were prepared in aqueous medium. JAGG formation can be tuned by means of the chemical structure of PPcys, the concentration of chromophores inside the polymeric NPs, and ultrasonication. The JAGG NPs exhibit a narrow emission band at 773 nm, a fluorescence quantum yield comparable to that of indocyanine green, and significantly enhanced photostability, which is ideal for long-term bioimaging. [ABSTRACT FROM AUTHOR]

ABSTRACT Narrow bandgap and hyperbranched polymers (h-PTDPP) are synthesized by directly arylation polymerization (DAP) of 2-bromo-thiophene-flanked diketopyrrolopyrrole (Br-TDPP) as the monomer. Their optical properties as well as chemical structures are studied. The detailed optimization of DAP conditions from catalyst, temperature, solvent, ligand to additive not only leads to high molecular weight h-PTDPP, but also provides some insight to minimize structural defects in DAP when brominated TDPP is involved as a monomer. The increase in the degree of branching results in lower charge-carrier mobilities in organic field-effect transistors involving h-PTDPP-3 as the semiconducting channel. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1040-1047 [ABSTRACT FROM AUTHOR]

Soya protein isolate (SPI)/alginate (ALG)/montmorillonite (MMT)/thymol (THY) nanocomposite films were prepared with a codrying process to enhance the antimicrobial stability. The results showed higher gelation point temperature and more stable gelling network were obtained by the addition of MMT. Better thermal stability and sustained release effect was found in the coblended film containing MMT, in which THY release rate at 25 °C decreased with increasing MMT concentration but increased with temperature at a constant relative humidity. The SPI/ALG/THY, SPI/ALG/THY-CO and SPI/ALG/THY-CO-0.6 (MMT content = 0.6 g g−1 SPI) films effectively inhibited the growth of Escherichia coli by 0.95, 0.91 and 0.70 log cfu mL−1 and of Staphylococcus aureus by 0.94, 0.89 and 0.73 log cfu mL−1, respectively, on the surface of raw sausage, compared to the control film. [ABSTRACT FROM AUTHOR]

Polycaprolactone (PCL) has been widely used in biomedical applications such as tissue engineering due to its promising biodegradability, biocompatibility, and mechanical processability. However, commercially available PCL without any fluorescence does not meet the increasing demand in biomedical applications, for example, to monitor noninvasively the fate of implanted scaffolds in tissue engineering. To that end, exploration of new fluorescent PCL polymers plays an essential role in tracking their degradation under physiological conditions and distinguishing PCL scaffolds at the interface with biological systems such as cells and tissues. Herein, this study reports a series of tailor-made fluorescent PCL polymers with various light emission wavelengths ranging from visible to near-infrared (NIR) region in solid states. These fluorescent PCL polymers are amenable to be processed into nanofibers using electrospinning, as well as waterborne nanoparticle ink for macroscale stamping, brush writing, and microcontact printing. Finally, the application of the NIR fluorescent PCL for in vitro imaging and monitoring of scaffold degradation is demonstrated. [ABSTRACT FROM AUTHOR]

ABSTRACT Thienoisoindigo (TIIG) has emerged as an attractive building block for high-performance organic optoelectronic devices. Here we report the first synthesis of a series of π-conjugated TIIG-based small molecules and alternating copolymers via direct C-H arylation, which enables the efficient synthesis without use of flammable and toxic orgametallic reagents in fewer steps compared Suzuki and Stille coupling. The direct arylation coupling between TIIG and two respective mono-bromo aryl reactants clearly shows that the α-H is more reactive than the β-H in the thiophene unit of TIIG. The high regioselectivity of TIIG monomer warrants the successful synthesis of high-quality alternating copolymers with minimal structural defects. PTIIG-BT polymer synthesized via direct arylation polymerization (DAP) showed comparable molecular weight and hole mobility than the same polymer previously synthesized via Suzuki coupling. Moreover, the two new polymers (PTIIG-TF and PTIIG-2FBT) synthesized via DAP showed hole mobility up to 10−3 cm2 V−1 s−1 in FET devices fabricated and tested under ambient conditions. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 2015-2031 [ABSTRACT FROM AUTHOR]

The synthesis of an ambipolar π-conjugated copolymer consisting of alternating diketopyrrolopyrrole and tetrafluorobenzene via direct arylation polymerization (DAP) is reported. Two different combinations of monomers are investigated under various catalytic conditions for DAP. The target polymer obtained under an optimized catalytic condition shows minimal structural defects, a number-average molecular weight of 33.2 kDa, and balanced electron and hole mobility of 1 x 10-2 cm² v-1 S-1 in the organic field-effect transistors fabricated and tested under ambient conditions. [ABSTRACT FROM AUTHOR]

ABSTRACT Well-defined 1,4-diketo-3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole (DTDPP) labeled polycaprolactones (PCL) with different chain lengths were synthesized and characterized. The effect of polymer chain lengths on the optical properties of DTDPP in solid states was studied by UV-Vis absorption spectroscopy as well as steady-state and dynamic fluorescence spectroscopies. Our results indicate that when the PCL side chain is extended to a certain length, the intermolecular aggregation of DTDPP units can be reduced significantly due to segregation effect of PCL. This approach offers a new facile strategy to address the common problem of aggregation-caused quenching existing in organic fluorophores. These highly fluorescent biodegradable PCL polymers may find broad biomedical applications such as fluorescence-based bioimaging and tissue engineering. © 2015 Wiley Periodicals, Inc. J. Polym. Sci. Part A: Polym. Chem. 2015, 53, 1032-1042 [ABSTRACT FROM AUTHOR]

ABSTRACT The first observation that PBBTPD, a low bandgap, ambipolar conjugated donor-acceptor (DA) polymer based on benzobisthiadiazole (BBT), possesses an open-shell singlet ground state as well as a thermally accessible triplet state is described. Similarly, interesting electronic behavior in semiconducting organic DA oligomers based on BBT is also observed. Theoretical predictions have suggested that such behavior is due to the biradicaloid character of BBT and we provide experimental evidence indicating that these predictions are correct. Furthermore, the open shell character strengthens as the conjugation length increases, as observed in the BBT-based polymer, PBBTPD. We show that this biradicaloid structure is observed in each BBT moiety along the chain and that therefore PBBTPD is in fact a polyradicaloid. This observation will most likely aid in the development of better n-type polymeric acceptors for organic semiconductor applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 287-293 [ABSTRACT FROM AUTHOR]

A mechanistic study of the DNA interfacial layer that enhances the photoresponse in n-type field-effect transistors (FET) and lateral photoconductors using a solution-processed fullerene derivative embedded with disperse-red dye, namely PCBDR, is reported. Incorporation of the thin DNA layer simultaneously leads to increasing the electron injection from non-Ohmic contacts into the PCBDR active layer in dark and to increasing the photocurrent under irradiation. Such features lead to the observation of the enhancement of the photoresponsivity in PCBDR FETs up to 103. Kelvin probe microscopy displays that in the presence of the DNA layer, the surface potential of PCBDR has a greater change in response to irradiation, which is rationalized by a larger number of photoinduced surface carriers. Transient absorption spectroscopy confirms that the increase in photoinduced carriers in PCBDR under irradiation is primarily ascribed to the increase in exciton dissociation rates through the PCBDR/DNA interface and this process can be assisted by the interfacial dipole interaction. [ABSTRACT FROM AUTHOR]

New conjugated oligomers, oligo(9,9-didodecylfluorene-bis-sulphurdiimide), consisting of 9,9-didodecylfluorene separated by NSN moieties, are reported. These oligomers are stable purple solids under ambient conditions with absorption covering a broad spectral window in the UV-vis range and a main broad peak centered at 555 nm with onset extending to 700 nm. These oligomers show an obviously longer conjugation length than its dimeric analogue, bis-9,9-didodecyl-fluorene-2-sulfurdiimide that shows a band-edge absorption centered at 484 nm with onset at 590 nm. The dimer and oligomers are soluble in a variety of organic solvents. Moreover, we found that the oligomer with an average repeating-unit number of six could significantly quench the photoluminescence (PL) of poly[2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV) or poly(3-hexylthiophene) (P3HT) in the solid state. More importantly, the composites of this oligomer with P3HT showed a nearly 10-fold enhancement of the photocurrent, compared with that of P3HT itself. In addition, the PL of this oligomer could be quenched by the presence of phenyl-C61-butyric acid methyl ester (PCBM) in toluene. These results suggest the presence of photoinduced charge transfer in composites of these oligomers blended with an electronic partner that either donates or accepts electrons. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The discovery of fluorescent proteins has inspired a lot of interest to develop synthetic polymers with similar structures and functionalities. In this review article, we first give a brief introduction for the discovery, the structural characteristics and optical properties of fluorescent proteins, using green fluorescent protein (GFP) as an example. In the body part of article, we summarize recent advances in molecular design, synthesis and processing of bioinspired fluorescent polymers with unique optical properties such as high fluorescence quantum yield and robust photostability. Several major approaches highlighted here include the recombination of organic chromophores and proteins, and synthesis of the bioinspired polymers containing a single fluorophore in each polymer chain. The optical properties and applications of some representative bioinspired fluorescent polymers in bioimaging, sensing and imaging‐guided therapy are also elucidated. [ABSTRACT FROM AUTHOR]

Near‐infrared fluorescent J‐aggregates were discovered in colloidal nanoparticles of pyrrolopyrrole cyanines stabilized by amphiphilic block co‐polymers in aqueous media. The formation of such colloidal‐state J‐aggregates can be tuned by the chemical structure and the concentration of the chromophores inside the polymeric nanoparticles, and can be further enhanced by ultrasonic treatment. These J‐aggregate nanoparticles with an average diameter of 30 nm, exhibit a narrow emission band at 773 nm, a fluorescence quantum yield comparable to that of indocyanine green, and significantly enhanced photostability that is ideal for long‐term bioimaging. More information can be found in the Full Paper by M. Wang et al. on page 4310 ff. [ABSTRACT FROM AUTHOR]