厦门大学"化学学科拔尖学生培养试验计划"的探索与实践

全面介绍了厦门大学化学学科拔尖学生培养试验计划的探索与实施,包括:目标定位、生源遴选、导师配备、课程体系、科研训练、管理机制和实施成效等。     

Molecular assembly of superquenchers in signaling molecular interactions

We have designed a novel molecular assembly of quencher molecules to form superquenchers with excellent quenching efficiency. The superquencher can be engineered as desired by assembling different types and different numbers of quencher molecules. By labeling a superquencher to a molecular beacon, a 320-fold enhancement of fluorescent signal was achieved, compared to about 14-fold from a molecular beacon prepared with the same monomer quencher. Our molecular assembly approach can effectively improve the sensitivity of a variety of fluorescent assays and can be widely useful for molecular interaction studies.     

Caged molecular beacons: controlling nucleic acid hybridization with light

We have constructed a novel class of light-activatable caged molecular beacons (cMBs) that are caged by locking two stems with a photo-labile biomolecular interaction or covalent bond. With the cMBs, the nucleic acid hybridization process can be easily controlled with light, which offers the possibility for a high spatiotemporal resolution study of intracellular mRNAs.     

Preparation and electro‐optical properties of polymer dispersed liquid crystal films with relatively low liquid crystal content

In this paper, polymer dispersed liquid crystals (PDLC) films with LC content as low as 40 wt% were prepared, and the electro‐optical properties were carefully investigated. To accomplish this, different (meth)acrylate copolymerizaiton monomers have been used. The electro‐optical properties and morphologies of the PDLC films were strongly influenced by the chemical structure of copolymerization monomers (hydroxypropyl methacrylate (HPMA), glycidyl methacrylate, hydroxypropyl acrylate) and their feed ratio. Lower driven voltage and higher contrast ratio were achieved when the PDLC films showed a morphology with suitably LC domain size. At high HPMA content, a thin polymer film was formed on the surface of PDLC samples, which is beneficial to decrease the total LC content in PDLC devices. Copyright © 2013 John Wiley & Sons, Ltd.     

A Multifunctional Nanomicelle for Real‐Time Targeted Imaging and Precise Near‐Infrared Cancer Therapy

Simultaneous targeted cancer imaging, therapy and real‐time therapeutic monitoring can prevent over‐ or undertreatment. This work describes the design of a multifunctional nanomicelle for recognition and precise near‐infrared (NIR) cancer therapy. The nanomicelle encapsulates a new pH‐activatable fluorescent probe and a robust NIR photosensitizer, R16FP, and is functionalized with a newly screened cancer‐specific aptamer for targeting viable cancer cells. The fluorescent probe can light up the lysosomes for real‐time imaging. Upon NIR irradiation, R16FP‐mediated generation of reactive oxygen species causes lysosomal destruction and subsequently trigger lysosomal cell death. Meanwhile the fluorescent probe can reflect the cellular status and in situ visualize the treatment process. This protocol can provide molecular information for precise therapy and therapeutic monitoring.     

Polyureas from diamines and carbon dioxide: synthesis, structures and properties

Polyureas were synthesized from diamines and carbon dioxide in the absence of any catalyst or solvent, analogous to the synthesis of urea from condensation of ammonia with carbon dioxide. The method used carbon dioxide as a carbonyl source to substitute highly toxic isocyanates for the synthesis of polyureas. FTIR and DFT calculations confirmed that strong bidentate hydrogen bonds were formed between urea motifs, and XRD patterns showed that the PUas were highly crystalline and formed a network structure through hydrogen bonds, which served as physical cross-links. The long chain PUas presented a microphase separated morphology as characterized by SAXS and showed a high melting temperature above 200 °C. The PUas showed high resistance to solvents and excellent thermal stability, which benefitted from their special network structures. The PUas synthesized by this method are a new kind of functional material and could serve some areas where their analogues with similar functional groups could not be applied.     

Highly sensitive and quantitative detection of rare pathogens through agarose droplet microfluidic emulsion PCR at the single-cell level

Genetic alternations can serve as highly specific biomarkers to distinguish fatal bacteria or cancer cells from their normal counterparts. However, these mutations normally exist in very rare amount in the presence of a large excess of non-mutated analogs. Taking the notorious pathogen E. coli O157:H7 as the target analyte, we have developed an agarose droplet-based microfluidic ePCR method for highly sensitive, specific and quantitative detection of rare pathogens in the high background of normal bacteria. Massively parallel singleplex and multiplex PCR at the single-cell level in agarose droplets have been successfully established. Moreover, we challenged the system with rare pathogen detection and realized the sensitive and quantitative analysis of a single E. coli O157:H7 cell in the high background of 100?000 excess normal K12 cells. For the first time, we demonstrated rare pathogen detection through agarose droplet microfluidic ePCR. Such a multiplex single-cell agarose droplet amplification method enables ultra-high throughput and multi-parameter genetic analysis of large population of cells at the single-cell level to uncover the stochastic variations in biological systems.     

Molecular Engineering of DNA: Molecular Beacons

Molecular beacons (MBs) are specifically designed DNA hairpin structures that are widely used as fluorescent probes. Applications of MBs range from genetic screening, biosensor development, biochip construction, and the detection of single‐nucleotide polymorphisms to mRNA monitoring in living cells. The inherent signal‐transduction mechanism of MBs enables the analysis of target oligonucleotides without the separation of unbound probes. The MB stem–loop structure holds the fluorescence‐donor and fluorescence‐acceptor moieties in close proximity to one another, which results in resonant energy transfer. A spontaneous conformation change occurs upon hybridization to separate the two moieties and restore the fluorescence of the donor. Recent research has focused on the improvement of probe composition, intracellular gene quantitation, protein–DNA interaction studies, and protein recognition.     

A Fluid Multivalent Magnetic Interface for High-Performance Isolation and Proteomic Profiling of Tumor-Derived Extracellular Vesicles

Isolation and analysis of tumor-derived extracellular vesicles (T-EVs) are important for clinical cancer management. Here, we develop a fluid multivalent magnetic interface (FluidmagFace) in a microfluidic chip for high-performance isolation, release, and protein profiling of T-EVs. The FluidmagFace increases affinity by 105-fold with fluidity-enhanced multivalent binding to improve isolation efficiency by 13.9 % compared with a non-fluid interface. Its anti-adsorption property and microfluidic hydrodynamic shear minimize contamination, increasing detection sensitivity by two orders of magnitude. Moreover, its reversibility and expandability allow high-throughput recovery of T-EVs for mass spectrometric protein analysis. With the chip, T-EVs were detected in all tested cancer samples with identification of differentially expressed proteins compared with healthy controls. The FluidmagFace opens a new avenue to isolation and release of targets for cancer diagnosis and biomarker discovery.