A novel test device and quantitative colorimetric method for the detection of human chorionic gonadotropin (hCG) based on Au@Zn-salen MOF for POCT applications.

The human chorionic gonadotropin (hCG) hormone is a biomarker that can predict tumors and early pregnancy; however, it is challenging to develop sensitive qualitative-quantitative procedures that are also effective, inventive, and unique. In this study, we used a novel easy in situ reaction of an organic nano-linker with Zn(NO3)2·6H2O and HAuCl4·3H2O to produce a gold-zinc-salen metal-organic framework composite known as Au-Zn-Sln-MOF. A wide variety of micro-analytical instruments and spectroscopic techniques were used in order to characterize the newly synthesized Au-Zn-Sln-MOF composite. Disclosure is provided for a novel swab test instrument and a straightforward colorimetric approach for detecting hCG hormone based on an Au-Zn-Sln-MOF composite. Both of these methods are easy. In order to validate a natural enzyme-free immunoassay, an Au-Zn-Sln-MOF composite was utilized in the role of an enzyme; a woman can use this gadget to determine whether or not she is pregnant in the early stages of the pregnancy or whether or not her hCG levels are excessively high, which is a symptom that she may have a tumor. This cotton swab test device is compatible with testing of various biological fluids, such as serum, plasma, or urine, and it can be easily transferred to the market to commercialize it as a costless kit, which will be 20-30% cheaper than what is available on the market. Additionally, it can be used easily at home and for near-patient testing (applications of point-of-care testing (POCT)).

S-scheme mesoporous Li2MnO3/g-C3N4 heterojunctions as efficient photocatalysts for the mineralization of trichloroethylene in aqueous media.

Novel mesoporous Li2MnO3/g-C3N4 heterostructures were prepared for the first time by utilizing the sol-gel route in the presence of a nonionic surfactant. TEM and XRD measurements showed that Li2MnO3 (5-10 nm) with monoclinic structures was uniformly distributed onto porous g-C3N4 for the construction of Li2MnO3/g-C3N4 heterojunctions. The obtained photocatalysts were assessed for mineralization and removal of trichloroethylene (TCE) in aqueous media under visible light exposure. Complete degradation of TCE over a 3 %Li2MnO3/g-C3N4 heterostructure within 120 min was achieved. The degradation rate over Li2MnO3/g-C3N4 heterostructures was significantly enhanced, and the 3% Li2MnO3/g-C3N4 heterostructure exhibited a large degradation rate of 7.04 µmolL-1 min-1, which was enhanced by 5 and 3.8 fold compared to those of pristine g-C3N4 (1.39 µmolL-1 min-1) and Li2MnO3 (1.85 µmolL-1 min-1), respectively. The photocatalytic efficiency of the Li2MnO3/g-C3N4 heterojunction was outstandingly promoted because integrating Li2MnO3 with g-C3N4 could create close interfaces with well-matched band potentials for easy mobility and low recombination of photoinduced carriers. The coexistence of Li2MnO3/g-C3N4 interfaces led to a synergic effect, which is considered the key factor in photoinduced electron-hole separation. The synthesis procedure that was employed here is a promising process for the preparation of effective g-C3N4-based photocatalyst systems for photocatalysis applications.

SrSnO3-Assembled MWCNT Heterojunctions for Superior Hydrogen Production under Visible Light.

A one-step sol-gel method for SrSnO3 nanoparticle synthesis and the incorporation of multi-walled carbon nanotubes (MWCNTs) to produce a SrSnO3@MWCNT photocatalyst is presented. The incorporation of MWCNTs results in enhancement of structural, optical, and optoelectrical properties of SrSnO3. The optimized 3.0% addition of MWCNTs results in light absorption enhancement and a reduction of the band gap from 3.68 to 2.85 eV. Upon application of the photocatalyst in the photocatalytic hydrogen production reaction, SrSnO3@MWCNT-3.0% yields 4200 µmol g-1 of H2 in just 9 h with the use of 1.6 g L-1 of the photocatalyst. SrSnO3@MWCNT exhibits remarkable chemical and photocatalytic stability upon regeneration. Enhanced photocatalytic ability is attributed to improved surface properties and charge-carrier recombination suppression induced by the MWCNT addition. This study highlights the remarkable improvements in chemical and physical properties of semiconductors with MWCNT incorporation.

Promoting Visible Light Generation of Hydrogen Using a Sol-Gel-Prepared MnCo2O4@g-C3N4 p-n Heterojunction Photocatalyst.

The production of hydrogen using a new type of heterogeneous photocatalyst under visible light is considered a remarkable essential pathway for sustainable, pure energy not only on the laboratory scale but also on a bigger scale. Hence, a new nanocomposite of mesoporous MnCo2O4, g-C3N4, and MnCo2O4@g-C3N4 was produced utilizing a sol-gel method with variable MnCo2O4 contents. The crystal structure of MnCo2O4 was effectively confirmed by the X-ray diffraction pattern and integrated onto the g-C3N4 structure. The MnCo2O4 nanoparticles were displayed as spherical particles by TEM images and dispersed in a uniform way inside the g-C3N4 nanosheet. The synthesized nanocomposites in the form of MnCo2O4@g-C3N4 were examined as a new effective photocatalyst against glycerol as a source for H2 production with visible light. The MnCo2O4 contents indicated a corroborative impact for the photocatalytic action related to the H2 production process. A maximum H2 production molecular value was observed (21,870 µmol·g-1·h-1) for a 1.5 wt % MnCo2O4@g-C3N4 nanocomposite as a considerable increase in its photocatalytic activity. The yields of H2 are ∼55 and 23 times higher than those of g-C3N4 and MnCo2O4, respectively. Up to five times cycles of visible lighting were the maximum number of repeated cycles by which the 1.5 wt % MnCo2O4@g-C3N4 product showed higher stability and durability.

Fabrication of Mesoporous PtO-ZnO Nanocomposites with Promoted Photocatalytic Performance for Degradation of Tetracycline.

Herein, we report a simple incorporation of PtO NPs at diverse percentages (0.2-0.8 wt %) onto a highly crystalline and mesoporous ZnO matrix by the wet-impregnation approach for degradation of tetracycline (TC) upon visible light exposure. These well-dispersed and small-sized PtO NPs provide the mesoporous PtO-ZnO nanocomposites with outstanding photocatalytic performance for complete TC degradation. The optimized 0.6% PtO-ZnO photocatalyst exhibits excellent TC degradation, and its degradation efficiency reached ∼99% within 120 min. The photocatalytic performance of the 0.6% PtO-ZnO nanocomposite is 20 and 10 times higher than that of pristine ZnO and commercial P-25, respectively. The photodegradation rate of TC over the 0.6% PtO-ZnO nanocomposite is 34 and 12.5 times greater than that of pristine ZnO and commercial P-25, respectively. This is because of the large surface area, unique porous structure, synergistic effect, and broad visible light absorption of the PtO-ZnO nanocomposite. Moreover, mesoporous PtO-ZnO nanocomposites showed a high stability and recyclability over five iterations. This work demonstrates the remarkable role of combining PtO and ZnO photocatalysts in providing nanocomposites with significant potential for the preservation of human health through wastewater remediation.

Generation of Hydrogen Gas Using CuCr2O4-g-C3N4 Nanocomposites under Illumination by Visible Light.

In this research, nanocomposites made of CuCr2O4-g-C3N4 accommodating distinct contents of CuCr2O4 (1-4 wt %) nanoparticles (NPs) were endorsed for hydrogen gas production after illumination by visible light in the presence of aqueous glycerol solution. The ultrasonication-mixture method was applied to assure the homogeneous distribution of CuCr2O4 NPs over synthesized mesoporous g-C3N4. Such nanocomposites possess suppressed recombination between the photoinduced charges. High-resolution transmission electron microscopy and X-ray photoelectron spectroscopy examinations affirmed the formation of CuCr2O4-g-C3N4 heterojunctions. The separation between the induced charges and the photocatalytic performance with the CuCr2O4 NP amount were investigated. The CuCr2O4-g-C3N4 heterojunction of 3 wt % CuCr2O4 content was documented as the optimal heterojunction. Upgraded hydrogen gas generation was attained over the optimal heterojunction with the extent of ten and thirty times as those registered for pure CuCr2O4 and g-C3N4 specimens, respectively, under illumination by visible light. The photocatalytic performance acquired by the diverse synthesized specimens was assessed not only by their effectiveness to absorb light in the visible region but also by their potential to separate the photoinduced charges.

Soft and hard templates assisted synthesis mesoporous CuO/g-C3N4 heterostructures for highly enhanced and accelerated Hg(II) photoreduction under visible light.

Herein, triblock copolymer surfactant (F127) and mesoporous silica (MCM-41) as soft and hard templates were employed to synthesize of mesoporous CuO/g-C3N4 heterostructures with large surface areas for Hg(II) photoreduction in existence of formic acid as a holes sacrificial. TEM image for mesoporous CuO/g-C3N4 indicated that CuO NPs are homogeneously distributed with spherical shape in particle size ~5 nm onto the surface of g-C3N4. Mesoporous 2%CuO/g-C3N4 heterostructure was achieved a high Hg(II) photoreduction rate of 628.74 µmolg-1h-1 and high photoreduction efficiency of ~100% within 50 min compared with the pure either mesoporous CuO NPs (130.11 µmolg-1h-1, 21%) and g-C3N4 (88.54 µmolg-1h-1, 14%). The highest Hg(II) photoreduction rate achieved was 628.74 µmolg-1h-1, which is 4.83 and 7.1 magnitudes stronger than mesoporous CuO NPs and g-C3N4. The excellent photocatalytic performance of mesoporous CuO/g-C3N4 heterostructures for Hg(II) photoreduction is referred to highly dispersed mesoporous CuO NPs with small particle size onto g-C3N4, narrow bandgap, large surface area, a rapid transfer of Hg(II) ions and HCOOH to easily reach the active sites due to the facile penetration through the mesostructure, thus promoting the utilization of porous structure of CuO/g-C3N4 heterostructures for efficient diffusion of Hg(II) ions. The intense interaction between mesoporous CuO NPs and porous g-C3N4 confirms the durability of the CuO/g-C3N4 heterostructures during recyclability for five times.

Facile Synthesis of Mesoporous Ag2O-ZnO Heterojunctions for Efficient Promotion of Visible Light Photodegradation of Tetracycline.

Fabrication of 3D mesoporous Ag2O-ZnO heterojunctions at varying Ag2O contents has been achieved through poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) (Pluronic F-108) as the structure-directing agent for the first time. The mesoporous Ag2O-ZnO nanocomposites exhibited a mesoporous structure, which revealed a large pore volume and high surface area. The photocatalytic efficiency over mesoporous Ag2O-ZnO nanocomposites for tetracycline (TC) compared with that over commercial P-25 and pristine ZnO NPs through the visible light exposure was studied. Mesoporous 1.5% Ag2O-ZnO nanocomposites indicated the highest degradation efficiency of 100% of TC during 120 min of the visible light exposure compared with 5% and 10% for pristine ZnO NPs and commercial P-25, respectively. The TC degradation rate took place much rapidly over 1.5% Ag2O-ZnO nanocomposites (0.798 µmol L-1 min-1) as compared to either commercial P-25 (0.097 µmol L-1 min-1) or ZnO NPs (0.035 µmol L-1 min-1). The mesoporous 1.5% Ag2O-ZnO nanocomposite revealed the highest degradation rate among all synthesized samples, and it was 23 and 8 orders of magnitudes greater than those of pristine ZnO NPs and P-25, respectively. The photoluminescence and transient photocurrent intensity behaviors have been discussed to explore photocatalysis mechanisms. It is anticipated that the present work will contribute some suggestions for understanding other heterojunctions with outstanding behaviors.

Silver-Doped Antimony Trioxide Nanocomposites for the Photocatalytic Reduction of Nitrobenzene.

A sol-gel technique was used to synthesize silver-doped antimony trioxide nanocomposites. Antimony trioxide and silver-doped antimony trioxide samples were characterized by multiple techniques. The TEM images reveal that antimony trioxide and silver-doped antimony trioxide nanocomposites have nanoparticle shapes. Antimony trioxide has a wide band gap that can be controlled by the doping of silver, and the content of doped silver plays a vital role controlling the band gap energy. The photocatalytic performance of antimony trioxide and silver-doped antimony trioxide nanocomposites was investigated via aniline preparation from the photocatalytic reduction of nitrobenzene. The XPS results reveal that the silver is found in the metallic silver state. Silver doping improves the photocatalytic activity of antimony trioxide for the preparation of aniline. This effect can be ascribed to the narrowing of the band gap and the elongation of the lifetime for electron-hole recombination of antimony trioxide photocatalyst by silver doping. Thus, a photocatalyst with improved photocatalytic activity, limited band gap and improved e-h recombination rate was synthesized by a facile sol-gel process method.

Different techniques for management of common bile duct stones: a single centre experience.

Local experience on the combined technique of endoscopic sphincterotomy followed by endo: scopic balloon dilation is scarce. This study clarified whether this crombined technique will offer any advantages, with respect to therapeutic outcome and complications rate, as compared with endoscopic sphincterotomy (ES) and endoscopic balloon dilatation (EBD) alone for the extraction of large and/or multiple common bile duct stones. For a total of 76 patients, extraction of large and/or multiple common bile duct (CBD) stones during endoscopic retrograde cholangiopancreatography was performed. According to the used technique, they were categorized into 3 groups; Endoscopic sphincterotomy, endoscopic balloon dilatation or combined technique. The success rate of complete stone removal and the incidence of procedure-related complications were compared among the three groups. Success rate after one session was recorded to be comparable among the three groups. Relative Risk Ratio assessment of success rate after single session among the three groups showed no statistically significant difference. Regarding bleeding, only 3 (10%) cases were recorded in the ES group with no cases in the, other 2 groups. No significant difference was noted among the three groups regarding other complication. The combined technique of ES followed by EBD is an effective and safe technique enables extraction of multiple and/or relatively large stones. It could be a reasonable alternative option when standard techniques are inadequate to remove bile duct stones.

Enhancement of titania by doping rare earth for photodegradation of organic dye (Direct Blue).

Lanthanide ions (La(3+), Nd(3+), Sm(3+), Eu(3+), Gd(3+), and Yb(3+))/doped TiO2 nanoparticles were successfully synthesized by sol-gel method. Their photocatalytic activities were evaluated using Direct Blue dye (DB53) as a decomposition objective. The structural features of TiO2 and lanthanide ions/TiO2 were investigated by XRD, SEM, UV-diffuse reflectance, and nitrogen adsorption measurements. Our findings indicated that XRD data characteristic anatase phase reflections and also XRD analysis showed that lanthanides phase was not observed on Lanthanide ions/TiO2. The results indicated that Gd(3+)/TiO2 has the lowest bandgap and particle size and also the highest surface area and pore volume (V(p)) as well. Lanthanide ions can enhance the photocatalytic activity of TiO2 to some extent as compared with pure TiO2 and it was found that Gd(3+)/TiO2 is the most effective photocatalyst. The photocatalytic tests indicate that at the optimum conditions; illumination time 40 min, pH approximately 4, 0.3g/L photocatalyst loading and 100 ppm DB53; the dye removal efficiency was 100%. Details of the synthesis procedure and results of the characterization studies of the produced lanthanide ions/TiO2 are presented in this paper.