METHOD: TQ-nanoparticles were prepared and optimized by using two different formulations with different drugs to PLGA-PEG ratio (1:20 and 1:7) and different PLGA-PEG to Pluronic F68 ratio (10:1 and 2:1). The morphology and size were determined using TEM and DLS. Characterization of particles was done using UV-VIS, ATR-IR, entrapment efficiency, and drug release. The effects of drug, polymer, and surfactants were compared between the two formulations. Cytotoxicity assay was performed using MTS assay.
RESULTS: TEM finding showed 96% of particles produced with 1:7 drug to PLGA-PEG were less than 90 nm in size and spherical in shape. This was confirmed with DLS which showed smaller particle size than those formed with 1:20 drug to PLGA-PEG ratio. Further analysis showed zeta potential was negatively charged which could facilitate cellular uptake as reported previously. In addition, PDI value was less than 0.1 in both formulations indicating monodispersed and less broad in size distribution. The absorption peak of PLGA-PEG-TQ-Nps was at 255 nm. The 1:7 drug to polymer formulation was selected for further analysis where the entrapment efficiency was 79.9% and in vitro drug release showed a maximum release of TQ of 50%. Cytotoxicity result showed IC50 of TQ-nanoparticle at 20.05 μM and free TQ was 8.25 μM.
CONCLUSION: This study showed that nanoparticle synthesized with 1:7 drug to PLGA-PEG ratio and 2:1 PLGA-PEG to Pluronic F68 formed nanoparticles with less than 100 nm and had spherical shape as confirmed with DLS. This could facilitate its transportation and absorption to reach its target. There was conserved TQ stability as exhibited slow release of this volatile oil. The TQ-nanoparticles showed selective cytotoxic effect toward UACC 732 cells compared to MCF-7 breast cancer cells.
METHODS: Adaxial walls of leaf epidermal cells were characterized using high-pressure-frozen freeze-substituted specimens, which retain their native dimensions during observations using transmission and scanning microscopy, accompanied by energy-dispersive X-ray spectroscopy to identify the role of biogenic silica in wall-based iridescence. Biogenic silica was experimentally removed using aqueous Na2CO3 and optical properties were compared using spectral reflectance.
KEY RESULTS AND CONCLUSIONS: Blue iridescence is produced in the adaxial epidermal cell wall, which contains helicoid lamellae. The blue iridescence from cell surfaces is left-circularly polarized. The position of the silica granules is entrained by the helicoid microfibrillar layers, and granules accumulate at a uniform position within the helicoids, contributing to the structure that produces the blue iridescence, as part of the unit cell responsible for 2 ° Bragg scatter. Removal of silica from the walls eliminated the blue colour. Addition of silica nanoparticles on existing cellulosic lamellae is a novel mechanism for adding structural colour in organisms.
OBJECTIVE: In the current scenario, the development of safe and effective drug delivery systems is the utmost concern of formulation development scientists as well as clinicians.
METHODS: Google, Web of Science, and PubMed portals have been searched for potentially relevant literature to get the latest developments and updated information related to different aspects of green synthesized AgNPs along with their biomedical applications, especially in the treatment of different types of cancers.
RESULTS: The present review highlights the latest published research regarding the different green approaches for the synthesis of AgNPs, their characterization techniques as well as various biomedical applications, particularly in cancer treatment. In this context, environment-friendly AgNPs are proving themselves as better candidates in terms of size, drug loading and release efficiency, targeting efficiency, minimal drug-associated side effects, pharmacokinetic profiling, and biocompatibility issues.
CONCLUSION: With continuous efforts by multidisciplinary team approaches, nanotechnology-based AgNPs will shed new light on diagnostics and therapeutics in various disease treatments. However, the toxicity issues of AgNPs need greater attention as unanticipated toxic effects must be ruled out for their diversified applications.