Fraxinus paxiana bark mediated photosynthesis of silver nanoparticles and their size modulation using swift heavy ion irradiation

The genus Fraxinus L. (Oleaceae): A review of botany, traditional and modern applications, phytochemistry, and bioactivity

Fraxinus L., a member of the Oleaceae family with approximately 60 species worldwide, is widely distributed in the warm temperate zone of the northern hemisphere. It is not only used as a folk medicine for treating various illnesses but is also documented in medical books. The traditional Chinese medicine "Qin Pi" originated from this genus and is known for its efficacy in treating conditions such as intestinal inflammation, redness and pain in the eyes, abomination of redness and leucorrhoea, and bacterial infections. This paper aims to fill the gap in the existing literature by providing a comprehensive review and critical analysis of the Fraxinus genus plant. The discussion in this paper covers various aspects of the plant, including its botany, traditional and modern applications, phytochemistry, bioactivity, role in ecosystems, phytogenetic evolution, economic benefits, and future challenges. By synthesizing this information, the review aims to offer valuable insights for the advancement, utilization, and further research of the Fraxinus spp.. Phytochemical studies have identified a total of 281 chemical constituents in Fraxinus spp., including secoiridoids, coumarins, and flavonoids. These Fraxinus spp. plants exhibit a wide range of biological activities, such as anti-inflammatory, antioxidant, and antibacterial properties. Furthermore, this paper delves into potential research directions within the genus and addresses the challenges associated with achieving a comprehensive understanding of Fraxinus spp. This paper provides a comprehensive overview of Fraxinus spp., highlighting their bioactivity mechanism and the opportunity to facilitate the advancement of new pharmaceuticals.

Refining shape and size of silver nanoparticles using ion irradiation for enhanced and homogeneous SERS activity

We present green synthesis of silver nanoparticles in water using unirradiated and Ag15 + ion irradiated phytoextracts of Bergenia Ciliata leaf, Eupatorium adenophorum leaf, Rhododendron arboreum leaf and flower. The use of different plant extracts and their subsequent ion irradiation allow for successful refinement of nanoparticle size and morphology. Due to changes in reducing and capping agents the nanoparticle surface functionalization also varies which not only controls the morphology but also allows for surface oxidation and aggregation processes. In this work, we have synthesized silver nanoparticles which exhibit sizes in the range from 13 to 24 nm and having shapes like spherical, quasispherical, trigonal, hexagonal, cylindrical, dendritic assemblies, and porous nanoparticles. Owing to changes in the size and shape of the nanoparticles, their direct bandgap (2.05 eV - 2.48 eV) and local surface plasmon resonance (420 nm - 490 nm) could also be tuned. These nanoparticles are examined as SERS substrates, where their enhancement factors, limit of detection for methylene blue, and SERS substrate homogeneity have been tested. It has been observed the nanoparticles synthesized using unirradiated plant extracts present an enhancement factor of 106 with a limit of detection 10- 8 M. Whereas nanoparticles with refined morphology and shapes upon irradiation present high enhancement factors of >107 and detection limit down to 10- 9 M. In addition, uniformity in Raman spectra over the SERS substrates has been obtained for selected Ag NPs substrates synthesized using irradiated extracts with minimum relative standard deviation in enhancement factor < 12%.

SAXS Combined with UV-vis Spectroscopy and QELS: Accurate Characterization of Silver Sols Synthesized in Polymer Matrices

The present work demonstrates a validation of small-angle X-ray scattering (SAXS) combining with ultra violet and visible (UV-vis) spectroscopy and quasi-elastic light scattering (QELS) analysis for characterization of silver sols synthesized in polymer matrices. Polymer matrix internal structure and polymer chemical nature actually controlled the sol size characteristics. It was shown that for precise analysis of nanoparticle size distribution these techniques should be used simultaneously. All applied methods were in good agreement for the characterization of size distribution of small particles (less than 60 nm) in the sols. Some deviations of the theoretical curves from the experimental ones were observed. The most probable cause is that nanoparticles were not entirely spherical in form.