Plant-Based Synthesis of Gold Nanoparticles and Theranostic Applications: A Review

Bionanotechnology is a branch of science that has revolutionized modern science and technology. Nanomaterials, especially noble metals, have attracted researchers due to their size and application in different branches of sciences that benefit humanity. Metal nanoparticles can be synthesized using green methods, which are good for the environment, economically viable, and facilitate synthesis. Due to their size and form, gold nanoparticles have become significant. Plant materials are of particular interest in the synthesis and manufacture of theranostic gold nanoparticles (NPs), which have been generated using various materials. On the other hand, chemically produced nanoparticles have several drawbacks in terms of cost, toxicity, and effectiveness. A plant-mediated integration of metallic nanoparticles has been developed in the field of nanotechnology to overcome the drawbacks of traditional synthesis, such as physical and synthetic strategies. Nanomaterials′ tunable features make them sophisticated tools in the biomedical platform, especially for developing new diagnostics and therapeutics for malignancy, neurodegenerative, and other chronic disorders. Therefore, this review outlines the theranostic approach, the different plant materials utilized in theranostic applications, and future directions based on current breakthroughs in these fields.     

Bis­[N,N‐bis(2‐hydroxy­ethyl)­di­thio­carbamato]­di­methyl­tin(IV)

The title compound, [Sn(CH₃)₂(C₅H₁₀NO₂S₂)₂], has crystallographic mirror symmetry (C—Sn—C on mirror plane) and the coordination polyhedron around the Sn atom is a tetrahedron [C—Sn—C 139.3 (2)° and S—Sn—S 82.3 (1)°] distorted towards a skew‐trapezoidal bipyramid owing to an intramolecular Sn?S contact [3.0427 (6) Å]. The mol­ecules are linked into a linear chain by intermolecular O—H?O hydrogen bonds [O?O 2.646 (3) Å].     

Potentiometric Studies on SomeCephalosporin Complexes

Summary.  The interaction of Ca(II), Cu(II), Zn(II), Pb(II), and La(III) ions with the antibiotics cephalexin, cefadroxil, cephaloridine, and cefoperazone as secondary ligands was investigated potentiometrically. The formation constants were determined for a ligand-to-metal ratio of 1:1 at 25°C and KNO₃. The protonation constants of the complexes were evaluated for the system . The order of stability of the binary and ternary complexes were examined. It was found that glycine adds preferably [M(II)-cephalosporin] rather than to the aqueous complexes of M(II). In all cases 1:1:1 complexes were formed. Received February 4, 2000. Accepted (revised) May 10, 2000     

Nanoformulation of Polyphenol Curcumin Enhances Cisplatin-Induced Apoptosis in Drug-Resistant MDA-MB-231 Breast Cancer Cells

Triple Negative Breast Cancer (TNBC) is the aggressive and lethal type of breast malignancy that develops resistance to current therapies. Combination therapy has proven to be an effective strategy on TNBC. We aimed to study whether the nano-formulation of polyphenolic curcumin (Gemini-Cur) would affect the cisplatin-induced toxicity in MDA-MB-231 breast cancer cells. MDA-MB-231 cells were treated with Gemini-Cur, cisplatin and combination of Gemini-Cur/Cisplatin in a time- and dose-dependent manner. Cell viability was studied by using MTT, fluorescence microscopy and cell cycle assays. The mode of death was also determined by Hoechst staining and annexin V-FITC. Real-time PCR and western blotting were employed to detect the expression of BAX and BCL-2 genes. Our data demonstrated that Gemini-Cur significantly sensitizes cancer cells to cisplatin (combination index ≤ 1) and decreases IC50 values in comparison with Gemini-cur or cisplatin. Further studies confirmed that Gemini-Cur/Cisplatin suppresses cancer cell growth through induction of apoptosis (p < 0.001). In conclusion, the data confirm the synergistic effect of polyphenolic curcumin on cisplatin toxicity and provide attractive strategy to attain its apoptotic effect on TNBC.     

Degrees-Of-Freedom in Multi-Cloud Based Sectored Cellular Networks

This paper investigates the achievable per-user degrees-of-freedom (DoF) in multi-cloud based sectored hexagonal cellular networks (M-CRAN) at uplink. The network consists of N base stations (BS) and K≤N base band unit pools (BBUP), which function as independent cloud centers. The communication between BSs and BBUPs occurs by means of finite-capacity fronthaul links of capacities CF=μF·12log(1+P) with P denoting transmit power. In the system model, BBUPs have limited processing capacity CBBU=μBBU·12log(1+P). We propose two different achievability schemes based on dividing the network into non-interfering parallelogram and hexagonal clusters, respectively. The minimum number of users in a cluster is determined by the ratio of BBUPs to BSs, r=K/N. Both of the parallelogram and hexagonal schemes are based on practically implementable beamforming and adapt the way of forming clusters to the sectorization of the cells. Proposed coding schemes improve the sum-rate over naive approaches that ignore cell sectorization, both at finite signal-to-noise ratio (SNR) and in the high-SNR limit. We derive a lower bound on per-user DoF which is a function of μBBU, μF, and r. We show that cut-set bound are attained for several cases, the achievability gap between lower and cut-set bounds decreases with the inverse of BBUP-BS ratio 1r for μF≤2M irrespective of μBBU, and that per-user DoF achieved through hexagonal clustering can not exceed the per-user DoF of parallelogram clustering for any value of μBBU and r as long as μF≤2M. Since the achievability gap decreases with inverse of the BBUP-BS ratio for small and moderate fronthaul capacities, the cut-set bound is almost achieved even for small cluster sizes for this range of fronthaul capacities. For higher fronthaul capacities, the achievability gap is not always tight but decreases with processing capacity. However, the cut-set bound, e.g., at 5M6, can be achieved with a moderate clustering size.     

Combining TOUGH2 and FLAC3D to Solve Problems in Underground Gas Storage

This paper describes modeling studies assessing the feasibility of increasing the maximum storage pressure in several underground natural gas storage reservoirs. This required an assessment of the potential for gas transport in the caprock and the geomechanical response to pressure change in the storage reservoir. To solve this problem in an efficient manner, two-phase flow (TOUGH2) and geomechanical (FLAC3D) models were combined in series. The TOUGH2 model was calibrated to fit pressure data collected on-site, from both the reservoir and caprock. The mechanical response of the caprock to increased storage pressure was modeled using FLAC3D, allowing assessment of the induced stresses in formations surrounding the reservoirs. We focused on two sites. In the first, field data were obtained from a deep borehole above the gas reservoir, which provided indirect observations of the geomechanical response of the caprock to pressure changes in the reservoir. In the second, open boreholes intersecting two thin caprock units immediately above the reservoir allowed gas flow to a shallower unit, significantly impacting the modeled fracture gradient.     

Excited state interaction between Hydrochlorothiazide and europium ion in PMMA polymer and its application as optical sensor for Hydrochlorothiazide in tablet and serum samples

This paper reports on a facile technique combined with a simple, sensitive and selective spectrofluorimetric method for the determination of hydrochlorothiazide. In methanol, at pH 8.3 and λ_ex=340, hydrochlorothiazide can remarkably enhance the luminescence intensity of the Eu³⁺ ion doped in polymethylmethacrylate polymer (PMMA) matrix. This could be due to the energy transfer from hydrochlorothiazide to Eu³⁺ in the excited stated. At the optimized experimental conditions, the enhancement of the characteristic emission band (617 nm) of Eu³⁺ ion doped PMMA is directly proportional to the concentration of hydrochlorothiazide with a dynamic range of 5×10^?8–1.0×10^?5 mol L^?1 and detection limit of 8.0×10^?9 mol L^?1. Application of the suggested method was successfully applied to the determination of hydrochlorothiazide in pharmaceutical preparations and human serum samples, with high percentage of recovery, good accuracy and precision.     

Spectrofluorimetric determination of melamine formaldehyde in solid and liquid forms and in wastewater

A new, simple and sensitive spectrofluorimetric method for determination of trace amount of melamine formaldehyde (MF) was developed. In phosphate buffer solution of pH 7.4 MF can remarkably quench the luminescence intensity of toluylene red (NR) at λ_em = 590 nm due to formation of NR-MF ion associate complex. The luminescence intensity of NR-MF complex was in proportion to the concentration of MF and used as photo probe for its determination. The dynamic range for the determination of MF is 7.5–52.5 ppm with detection limit of 4.4 ppm. The method is relatively free from interferences from coexisting substances and used successfully for the determining of MF in powder and liquid forms and in wastewater produced from MF industries. The average recoveries and standard deviations of 98.3 ± 0.6, 98.1 ± 0.6 and 97.3 ± 0.5% were achieved for determination of MF in solid, liquid forms and wastewater, respectively