Theoretical Investigation on Porphyrin-Based Small Molecules as Donor Materials for Photovoltaic Applications

An effective strategy to improve the efficiency of organic solar cells (OSCs) is to incorporate the porphyrin derivatives as electron-rich units into the acceptor–donor–acceptor molecules. To achieve this goal, starting from the parent molecules DTS­(PTTh2)2 and DTS­(FBTTh2)2 which are based on a dithieno­(3,2-b;2′,3′-d)­silole (DTS) electron-rich unit connected to each of two electron-withdrawing units ([1,2,5]­thiadiazolo­[3,4-c]­pyridine (PT) and 5-fluorobenzo­[c]­[1,2,5]­thiadiazole (FBT)), we designed two types of porphyrin-based small molecules by replacing DTS unit with the porphyrin derivatives in DTS­(PTTh2)2 and DTS­(FBTTh2)2, respectively. From the calculated results, the porphyrin-based molecules in OSC applications not only yield an enhanced light absorptions with a redshift and stronger spectra and increased hole mobility, which is conducive to enhance the short circuit current and fill factor, but also exhibit smaller exciton binding energy and better electron transfer properties at donor/acceptor (D/A) interface in comparison with the parent molecules. According to the predicted crystal structure for porphyrin-based molecules, the hole mobilities of the porphyrin-based molecules (S1b, S1c, S2b, and S2c) are 0.240, 0.166, 0.124, 0.511 cm2 V–1 s–1, respectively. In view of the excellent properties, the porphyrin-based molecules as donor materials can act as a good candidates for providing a large short-circuit current and fill factor in OSC applications

Nanozyme Rich in Oxygen Vacancies Derived from Mn-Based Metal–Organic Gel for the Determination of Alkaline Phosphatase

Vacancy engineering as an effective strategy has been widely employed to regulate the enzyme–mimic activity of nanomaterials by adjusting the surface, electronic structure, and creating more active sites. Herein, we purposed a facile and simple method to acquire transition metal manganese oxide rich in oxygen vacancies (OVs-Mn2O3-400) by pyrolyzing the precursor of the Mn(II)-based metal–organic gel directly. The as-prepared OVs-Mn2O3-400 exhibited superior oxidase-like activity as oxygen vacancies participated in the generation of O2•–. Besides, steady state kinetic constant (Km) and catalytic kinetic constant (Ea) suggested that OVs-Mn2O3-400 had a stronger affinity toward 3,3′,5,5′-tetramethylbenzidine and possessed prominent catalytic performance. By taking 2-phospho-l-ascorbic acid as the substrate, which can be converted into reducing substance ascorbic acid in the presence of alkaline phosphatase (ALP), OVs-Mn2O3-400 can be applied as an efficient nanozyme for ALP colorimetric analysis without the help of destructive H2O2. The colorimetric sensor established by OVs-Mn2O3-400 for ALP detection showed a good linearity from 0.1 to 12 U/L and a lower limit of detection of 0.054 U/L. Our work paves the way for designing enhanced enzyme-like activity nanozymes, which is of significance in biosensing

Nanozymes from Cu(II) Metal–Organic Gel and Melamine for Highly Active Peroxidase-Like Activity to Detect Alkaline Phosphatase

Enzyme-like catalytic activity and efficiency of carbon-based nanomaterials are closely linked to their size, heteroatom composition, and structure, and hence the heteroatom regulation needs to be further explored. In this work, a simple and efficient strategy was proposed to develop Cu-doped 2D carbon material C3N4 (Cu-C3N4-550) with excellent catalytic performance by pyrolyzing precursors of Cu(II) metal–organic gel (MOG) and melamine directly. Due to its sufficient metal active sites and adequate specific surface areas, the as-prepared Cu-C3N4-550 was endowed with excellent peroxidase-like activity to promote the oxidation of 3,3′,5,5′-tetramethylbenzidine owing to the generation of •OH in the catalytic reaction. It was amazing to find that the peroxidase mimic activity of the prepared Cu-C3N4-550 has enhanced 32.3-fold compared with bare C3N4. High peroxidase-like activity of Cu-C3N4-550 was influenced severely by the addition of antioxidant ascorbic acid (AA), alkaline phosphatase (ALP) as a typical hydrolase could catalyze substrate 2-phospho-l-ascorbic acid into AA, while AA was capable of capturing •OH generated from the catalytic reaction of Cu-C3N4-550. Hence, a sensitive, selective, and colorimetric method for the detection of ALP was established, the linear concentration of ALP in this colorimetric sensor from 0.4 to 20 U/L was acquired with a low detection limit of 0.32 U/L. This work not only provides ideas for designing enhanced peroxidase-like activity nanozymes in practical biological analysis but also broadens the MOG derivatives and carbon-based nanomaterials in colorimetric applications

Relationship of both volumetric water content and resistivity with the depth of the loess column under different rainfall.

(a) ρd = 1.42g/cm3, (b) ρd = 1.50g/cm3, (c) ρd = 1.58g/cm3.</p

Variation curves of resistivity with the depth of the loess column under light rain.

(a) ρd = 1.42g/cm3, (b) ρd = 1.50g/cm3, (c) ρd = 1.58g/cm3.</p

Variation curves of resistivity with the depth of the loess column under heavy rain.

(a) ρd = 1.42g/cm3, (b) ρd = 1.50g/cm3, (c) ρd = 1.58g/cm3.</p

Main physical parameters of loess.

Main physical parameters of loess.</p

DataSheet_1_Effective Delivery of siRNA-Loaded Nanoparticles for Overcoming Oxaliplatin Resistance in Colorectal Cancer.pdf

Chemotherapy resistance represents a formidable obstacle in advanced or metastatic colorectal cancer (CRC) patients. It is reported that ATPase copper transporting alpha (ATP7A) plays an important role in chemotherapy resistance in CRC. Here, we identified ATP7A as a potentially key gene of OXA resistance in CRC. The patients with higher expression of ATP7A tended to have platinum drug resistance. While the lower expression of ATP7A by siRNA knockdown resulted in enhancement of OXA sensitivity and increased OXA-induced apoptosis. Further, we demonstrated a novel and safe strategy to increase CRC chemosensitivity by delivering siRNA into tumor cells via a novel nanoparticle, DAN. In summary, our study provided a novel nanocarrier-based delivery of ATP7A to interfere in a key gene of chemo-resistance in CRC, which may be a novel therapeutic strategy to overcome chemotherapy resistance in CRC.</p

The fitting curve of resistivity and saturation.

The fitting curve of resistivity and saturation.</p

Sample preparation processes.

(a) Weigh soil samples, (b) Preparation of soil samples, (c) Layered filling soil column, (d) Measurement system installation.</p