A novel AIE-active imidazolium macrocyclic ratiometric fluorescence sensor for pyrophosphate anion.

An imidazolium bridged macrocyclophane was synthesized as a ratiometric fluorescence sensor with aggregation-induced emission (AIE) characteristic to detect pyrophosphate anion with high selectivity among various anions. In the presence of zinc ion, macrocyclophane can form aggregates through complexation with pyrophosphate anion and emit ratiometric fluorescence, resulting from an enhancement in its aggregate-state emission and a reduction in its monomer emission. This AIE-active macrocycle showed great potential as a ratiometric fluorescence receptor.

Author Correction: Chiral recognition and enantiomer excess determination based on emission wavelength change of AIEgen rotor.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Chiral recognition and enantiomer excess determination based on emission wavelength change of AIEgen rotor.

Chiral recognition, such as enantioselective interactions of enzyme with chiral agents, is one of the most important issues in the natural world. But artificial chiral receptors are much less efficient than natural ones. For tackling the chiral recognition and enantiomer excess (ee) analysis, up until now all the fluorescent receptors have been developed based on fluorescence intensity changes. Here we report that the chiral recognition of a large number of chiral carboxylic acids, including chiral agrochemicals 2,4-D, is carried out based on fluorescent colour changes rather than intensity changes of AIEgen rotors. Moreover, the fluorescence wavelength of the AIEgen rotor linearly changes with ee of the carboxylic acid, enabling the ee to be accurately measured with average absolute errors (AAE) of less than 2.8%. Theoretical calculation demonstrates that the wavelength change is ascribed to the rotation of the AIEgen rotor upon interaction with different enantiomers.

Surgical treatment for chronic achilles tendon rupture and severe scarring / 中国骨伤

<p><b>OBJECTIVE</b>To evaluate the clinical efficacy of autologous semitendinosus and gracilis tendon grafting with anchor repair for the treatment of chronic achilles tendon rupture and severe scarring.</p><p><b>METHODS</b>From April 2010 to October 2012,26 patients with chronic achilles tendon rupture(with Myerson type III ) and severe scarring were treated with autologous semitendinosus and gracilis tendon grafting with anchor repair. There were 19 males and 7 females,with an average age of 32 years old (ranged, 22 to 47 years). The time from injury to surgery was from 3 to 12 months (7 months on average). The plantar flexion strength of all injuried feet attenuated and single heel rise test were positive in 26 cases before operation. Plaster immobilization and routine rehabilitation therapy were performed after operation. Clinical effects were evaluated by Arner-lindholm criterion and complications were observed after operation.</p><p><b>RESULTS</b>All the patients were followed up from 12 to 24 months with a mean of 16 months. No complications such as achilles tendon re-rupture, wound infection, etc were found during follow-up period. According to the Arner-Lindholm standard, 15 cases got excellent results and 11 good.</p><p><b>CONCLUSION</b>Using autologous semitendinosus and gracilis tendon grafts with anchor repair to treat chronic achilles tendon rupture and severe scarring is a perfect surgical procedure.</p>

Monomer emission and aggregate emission of TPE derivatives in the presence of γ-cyclodextrin.

It was found for the first time that neutral amphiphilc tetraphenylethylene (TPE) derivatives showed an enhanced monomer emission and a decreased aggregate emission when they were included in the cavity of γ-cyclodextrin. This result provided a new insight into the aggregation-induced emission (AIE) effect.

Different morphologies of silica synthesized using organic templates from the same class of chiral compounds.

Rarely known round silica tubes with a hollow shell and square silica tubes, in addition to convenient hollow spheres, hollow spheres with a hole, and helical nanoribbons, could be synthesized using organic templates from the same class of organic compounds, arylacrylonitrile tartaric acids. A novel process of dissolving and re-assembling of template aggregates was the reason for forming a variety of morphologies of silica except square silica tubes which were directly controlled by template aggregates. The chirality of the template molecules played a key role in the formation mechanism of silica, in which not only the chirality of the silica nanoribbons but also the silica morphology could be controlled by the chirality of the template molecules.

Highly sensitive determination of enantiomeric composition of chiral acids based on aggregation-induced emission.

A new chiral tetraphenylethylene derivative with the AIE effect was synthesized and showed not only high enantioselectivity for a wide range of chiral acids but also a high sensitivity of 3.0 × 10(-6) M scale. The enantiomeric purity of chiral acids could be quantitatively determined by this chiral sensor.

Light-emitting property of simple AIE compounds in gel, suspension and precipitates, and application to quantitative determination of enantiomer composition.

It was found that simple AIE compounds could emit different intensity of fluorescence in gel, suspension and precipitates for the first time, which could be applied to fluorescence switches and quantitative determination of enantiomer composition.

Effect of carboxylic acid on micelles of a neutral amphiphilic dendro-calix[4]arene.

An amphiphilic calix[4]arene bearing branched 3,4,5-tris(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)benzamide groups at the upper rim was synthesized and could increase the solubility of naproxen and ibuprofen in water through hydrogen bonding and π-π stacking interactions. The interactions between amphiphilic calix[4]arene and carboxylic acids such as naproxen and ibuprofen could reverse the direction of the branched substituents and change the shape and size of calixarene micelles from solid to hollow or linear ones.

Highly enantioselective recognition of a wide range of carboxylic acids based on enantioselectively aggregation-induced emission.

A new chiral fluorescence receptor, designed to exploit aggregation-induced emission (AIE), exhibited not only an exceptionally high enantioselectivity but was also applicable to a wide range of chiral carboxylic acids. The fluorescence intensity ratio of two enantiomers ranged from 10 to 1.6 × 10(4) and could be used to determine the purity of the enantiomers.

Single-hole hollow nanospheres from enantioselective self-assembly of chiral AIE carboxylic acid and amine.

Phenylacrylonitrile tartaric acids have been found to enantioselectively self-assemble with an enantiomer of a chiral amine to form either nanofibers or nanospheres that exhibit aggregation-induced emission (AIE). The nanofibers exhibited stronger emission intensity and longer wavelengths of absorption and emission than the nanospheres because of increased π-π conjugation, an effect previously unseen in AIE. When the solvent consists of a mixture of water and THF rather than water and ethanol, the resultant nanospheres have holes. The holes are the result of the dissolution of defects and a decrease in the bending energy. This is in contrast to hole formation from solvents flowing out of the nanospheres, as previously seen. Through control of the water/THF ratio, the size of the holes in the nanospheres can be tuned. Nanospheres with a single hole displayed both higher uptake capacity and larger release speed of the drug naproxen than closed nanospheres. The ability to adjust fluorescent properties of AIE molecules through the preparation of organic single-hole hollow nanospheres has also been investigated along with the implications of the AIE mechanism.

A study of 22 displaced intraarticular calcaneal fractures using locking plates with and without bone graft / 中国骨伤

<p><b>OBJECTIVE</b>To analyze locking plates with bone graft fusion in treating displaced intraarticular calcaneal fractures and determine whether it is beneficial in maintaining restoration of calcaneal height and anatomic reduction of the articular surface.</p><p><b>METHODS</b>From January 2007 to January 2008, 22 patients with displaced intraarticular calcaneal fractures were treated with locking plates with and without bone graft (divided into the bone graft group and non-bone graft group). There were 17 males and 5 females, ranging in age from 18 to 59 years with the mean of 35 years. Sanders III was in 14 cases and Sanders IV in 8 cases. Autologous iliac bone filled defects with locking plates fixation for the bone graft group; just locking plates fixation were performed for non-bone graft group. The Böhler angle and Gissane angle were measured before and after operation. The foot function of two groups were compared according to Maryland standard at the 6th month, 1, 2 years after operation.</p><p><b>RESULTS</b>All patients were followed up with an average of 25 months. There was no significant difference in the recovery of Böhler angle and Gissane angle between two groups (P > 0.05). After the 6 months,1, 2 years, there was no significant difference in the foot function between two groups (P > 0.05), in bone graft group, excellent result was in 6, 7 ,7 cases respectively; and in non-bone graft group, excellent results in 5, 6, 7 cases respectively.</p><p><b>CONCLUSION</b>Bone graft in the surgical treatment of calcaneal fractures is not an advantage.</p>

Enantiomer analysis of chiral carboxylic acids by AIE molecules bearing optically pure aminol groups.

Pure enantiomers of carboxylic acids are a class of important biomolecules, chiral drugs, chiral reagents, etc. Analysis of the enantiomers usually needs expensive instrument or complex chiral receptors. However, to develop simple and reliable methods for the enantiomer analysis of acids is difficult. In this paper, chiral recognition of 2,3-dibenzoyltartaric acid and mandelic acid was first carried out by aggregation-induced emission molecules bearing optically pure aminol group, which was easily synthesized. The chiral recognition is not only seen by naked eyes but also measured by fluorophotometer. The difference of fluorescence intensity between the two enantiomers of the acids aroused by the aggregation-induced emission molecules was up to 598. The chiral recognition could be applied to quantitative analysis of enantiomer content of chiral acids. More chiral AIE amines need to be developed for enantiomer analysis of more carboxylic acids.