Enzyme-sensitive cytotoxic peptide-dendrimer conjugates enhance cell apoptosis and deep tumor penetration.

Peptide nanodrugs have been developed as promising antitumor chemotherapeutics because they partially overcome the drawbacks of free peptide drugs, but insufficient tumor penetration and interference of peptide function limit their further application. In this work, we have developed multifunctional peptide conjugated dendrimers for improving tumor penetration, cancer cell-specific peptide delivery and anticancer ability. The cytotoxic peptide KLAK, cell-penetrating peptide TAT and matrix metalloproteinase 2 (MMP2)-sensitive peptide-poly(ethylene glycol) (PEG) were conjugated onto dendrimers by one-pot synthesis to gain PKT-S-PEG.

A General Strategy for Facile Synthesis and In Situ Screening of Self-Assembled Polymer-Peptide Nanomaterials.

A universal strategy for efficient, mild, and purification-free synthesis and in situ screening of functional polymer-peptide nanomaterials is described. More than 1000 polymer-peptide conjugates (PPCs) with various chemical structures, compositions, and therapeutic efficacy are created. According to this strategy, the structure-function relationship of the PPCs is revealed, and the antitumor efficacies of the top performing PPCs are evaluated in vivo.

Self-assembled NIR nanovesicles for long-term photoacoustic imaging in vivo.

We report a supramolecular approach for the preparation of photostable NIR nanovesicles based on a cyanine dye derivative as a photoacoustic (PA) contrast agent for high-performance nano-imaging.

Synthesis of self-reporting polymeric nanoparticles for in situ monitoring of endocytic microenvironmental pH.

The bis(pyrene) conjugated pH-sensitive polymers () were synthesized and self-assembled into nanoparticles through hydrophobic interactions. The Nile red (NR) loaded nanoparticles showed red emission due to the FRET effect. The nanoparticles entered cells via endocytosis, and the microenvironmental pH in the endocytosis process was monitored in situ by the simultaneous dual-wavelength fluorescence changes.

A pH-responsive natural cyclopeptide RA-V drug formulation for improved breast cancer therapy.

The natural plant cyclopeptide RA-V, which was isolated from the roots of Rubia yunnanensis, was discovered to be a novel anti-cancer candidate. However, the cyclic hexapeptide exhibited poor solubility in physiological conditions, limiting its application for cancer therapy in vivo. To solve this problem, pH-sensitive polymers were developed for targeted RA-V delivery into tumor sites and for acid-triggered drug release.

Self-assembly of cytotoxic peptide conjugated poly(β-amino ester)s for synergistic cancer chemotherapy.

Nanotechnology has played an important role in cancer therapy due to the potential advantages of nano-drugs including enhanced accumulation in the tumor sites, improved pharmacokinetics and minimized systemic toxicity in vivo. Self-assembled peptides can improve the cellular internalization of peptides effectively through the endocytosis pathway for enhanced bioavailability. Herein, cytotoxic peptide (KLAKLAK) (named KLAK) conjugated poly(β-amino ester)s (PAE-KLAK) were synthesized by Michael-type addition.

DFT study of intermolecular [4 + 2] versus [3 + 2] cycloadditions in the dimerization of 2,4,6-trinitrotoluene (TNT): regioselectivity and stereoselectivity.

Two novel types of intermolecular hetero cycloadditions in the participation of the nitro group are put forward in the dimerization of TNT, in comparison with Diels-Alder cross-linking of benzene ring skeletons. Possible transition states and products; for example, their geometrical details, vibrational frequencies, and energies are verified at the B3LYP/6-31+G(d,p) level. Contrary to the hetero Diels-Alder reaction, the folding of the benzene ring side endo is slightly selective specific in 1,3-dipolar cycloaddition.

A study of the hydrogen abstraction reactions of C2H radical with CH3CN, C2H5CN, and C3H7CN by dual-level generalized transition state theory.

The hydrogen abstraction reactions C2H + CH3CN --> products (R1), C2H + CH3CH2CN --> products (R2), and C2H + CH3CH2CH2CN --> products (R3) have been investigated by dual-level generalized transition state theory. Optimized geometries and frequencies of all the stationary points and extra points along the minimum-energy path (MEP) are performed at the BH&H-LYP and MP2 methods with the 6-311G(d, p) basis set, and the energy profiles are further refined at the MC-QCISD level of theory. The rate constants are evaluated using canonical variational transition state theory (CVT) with a small-curvature tunneling correction (SCT) over a wide temperature range 104-2000 K.

Ab initio study of the spectroscopy of (CH3)(3)CN and (CH3)(2)CHN.

Using the complete active space self-consistent field (CASSCF) method with 6-311++g(3df,3pd) basis sets, a few electronic states of nitrenes (CH3)3CN and (CH3)2CHN and their positive ions are calculated. All calculated states are valence states, and their characteristics are discussed in detail. In order to investigate the Jahn-Teller effect on (CH3)3CN radical, Cs symmetry was used for (CH3)3CN and (CH3)2CHN in the calculations.

Ab initio study of the spectroscopy of CH3N and CH3CH2N.

Complete active space (CAS) calculations with 6-311++g(3df,3pd) basis sets were performed for a large number of electronic states of the nitrate free radical (CH3N/CH3CH2N) and their positive and negative ions. All calculated states are valence states, and their characters are discussed in detail. To investigate the Jahn-Teller effect on the CH3N radical, Cs symmetry was used for both CH3N and CH3CH2N in calculations.