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In a dispersion system, colloids interact with one another. It is assumed that these interactions are promoted by two main forces, London-van der Waals forces that lead to attraction and electromagnetic effects that leads to repulsion. The zeta potential (ZP) is the electrical potential at the surface of a hydrodynamic shear plane. It represents the net load of charged particles and is measured by a zetameter in millivolts. Synthetic constitutions exhibit cationic charge, while nearly all natural surfaces or molecules have a negative charge. The ionic strength of a solution is important and has quite a strong effect on the ZP because the ionic strength of a solution can alter the ZP and there is an optimal ZP for every target in the human body by the time it can reach its final destination. The ZP is an important parameter, and it is under the influence of many factors.

The development or designing of new and futuristic drug delivery systems have been mainly focused on nanoparticles and the drug, but the alteration of water properties or configuration of water molecules in these formulations have not been properly addressed yet. Quite strange and unexpected results have been obtained with nanoparticles or nanotubes when they were subjected to the diffusion or penetration experiments. It may be possible to alter water properties in these nanoparticulate systems without notice. Water molecules can be surrounded by nanoparticles or they can travel inside of nanotubes. They are then squeezed among or inside of them. It forms an unexpected and entirely new type of molecule, a new state of water; “Quantum water”. The altered dissolving ability of this water can result in alteration of dissolution characteristics of the solution. These may affect permeability, absorption, or bioavailability. All these alterations should be considered before introducing any nanoparticulate/drug system to the market for human use. This article represents some literature findings with unexpected results and gives some new interpretations considering possible consequences, reasons. This new horizon can open a new window and new requirements can be determined when nanoparticles are going to be used for humans. All these can give better clues for the researcher to explain what is happening in the nano environment in drug formulations with nanoparticles.

Diabetes is still one of the leading causes of death worldwide. According to the World Health Organization, around 1.5 million people worldwide died due to diabetes in 2019. It is estimated that 463 million people are living with diabetes all over the world. Many successful studies reported that splendid antihyperglycemic drugs can be developed with the help of new technologies and they can effectively deliver the active molecules by nanocarriers. In particular, recent studies show that some nanostructures namely quantum dots can be taken orally and their blood glucose-reducing effects are noteworthy. In our previous studies insulin was found to lower blood glucose levels when administered orally in liposome formulations. This study, it was aimed to examine whether carbon quantum dots can be used to transport insulin through the oral route and whether can they protect insulin from gastrointestinal enzymes as they can easily pass through both cell membranes and biological walls. It is also aimed to reveal the mechanism by which this effect occurs.

First off, fluorescent composite carbon quantum dots (N-doped) smaller than 10 nm were prepared with l-cysteine, treated with insulin, and decorated with poly ethylene glycol 3350 and methylcellulose for oral administration. As a result, these developed carbon quantum dots were administered orally to diabetic animals and their blood sugars were reduced by about 60% within 5 h.

It was then found that their blood levels were similarly reduced when prepared composite carbon quantum dots were orally administered alone to rats. It is found that although they do not contain any insulin, they increase the cellular response and metabolism in the mitochondria, causing glycolysis and thus having an antihyperglycemic effect when they are given orally. This is the first study in the literature that evaluated that the fine structure of the carbon quantum dot is important for having an antihyperglycemic effect and the l-quantum dot structure will be more effective.

An effective, dual drug(DD) loaded nanocarrier system (nano particle(NP), quantum dots(QDs)) having two active substances was aimed to develop for the treatment of fibrosarcoma. Zinc oxide(ZnO) QDs were produced using zinc acetate dehydrate as a precursor, were incorporated with chitosan(Ch), and finally decorated with PEG-linked folic acid and were found to be effective after imatinib mesylate(IM) and dexketoprofen trometamol(DT) were loaded. Characterisations, in vitro drug releases, cell toxicities, penetrations through cell lines and in-vivo animal tests of the prepared nanosystems were performed. The size of hybrid nanoparticles were 168.6 ± 48.8 nm, surface charge was −35.8 ± 0.26 mV. The encapsulation efficiency was 75% for IM and 99% for DT. DD-functionalised QDChNPs and lyophilised functionalised QDChNPs in capsules slowed down tumour growth by up to 76.5 and 88.7%. Our results demonstrate that developed hybrid nanoparticles are highly effective. This hybrid system gathers many of the advantages of nanotechnology into one form.

In addition to having strong anti-oxidant properties, resveratrol has anti-cancer, anti-angiogenic, cardioprotective, anti-diabetic, antiviral, and neuroprotective activities. Despite its rapid absorption, first-pass effect and intestinal metabolism reduce the bioavailability of resveratrol. Moreover, the lipophilic property of resveratrol reduces its water solubility and metabolized in high incidence reduces its oral bioavailability. Therefore, it was aimed to develop an optimum formulation for the skin application of resveratrol to overcome the

negatives after oral administration.Since their easy formulation, thermodynamically stable properties, and facilitating the delivery of both lipophilic and hydrophilic active ingredients, loading resveratrol to microemulsions (MEs) will be a suitable delivery system to overcome the drawback of stability problems and skin bioavailability of resveratrol. A Triangle phase diagram was constructed, and the MEs region was determined by points studies. Subsequently, some formulations were selected within the transparent region by

considering characteristics required to achieve optimized transdermal drug delivery. Chosen formulations were exposed to pre-stability tests such as centrifuge and thermal stress tests. Characterization studies such as droplet size, size distribution, zeta potential, viscosity, pH measurement were performed on remained intact formulations after pre-stability tests. In terms of the characterization test results such as pH, viscosity, conductivity, there wasn’t found significant difference observed between formulations. However, polydispersity index and zeta potential values provided to choosing optimal formulation.

In this study, an innovative approach to enhance the skin permeation, anti-aging and antioxidant effects of ferulic acid (FA)-loaded aspasomal formulations were developed and evaluated in vitro and ex vivo. The chemical interactions between FA and excipients in the formulation were characterized by Differential scanning calorimetry (DSC) and Fourier-transformed infrared (FTIR). Aspasomes (ASPs) were produced using the film hydration method with different components and were evaluated according to in vitro characterization parameters (particle size (PS), polydispersity index (PDI), zeta potential (ZP), scanning electron microscopy (SEM), drug entrapment efficiency (EE%) and drug release profile), and the optimized formulation was determined. The 3-(4,5-dimethyldiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to test the cytotoxicity of the ASPs and different FA solutions on the L929 cell line. In the stability studies, changes in characterization parameters and FA content of optimum ASPs stored in both suspended and lyophilized dry powder form in two different conditions over 3 months were monitored. Ex-vivo skin permeation study was done using mouse abdominal skin and the amount of penetrated FA was measured. Also, skin depth and density of blank and FA-loaded ASPs were evaluated by fluorescence microscopy. At the end of the permeation study, the antioxidant capacity of FA reaching the dermis layer and its inhibitory effect on collagenase and elastase enzymes were assessed. FTIR spectra and DSC thermograms assured chemical and physical compatibility. The selected optimum formulation (F2 coded) showed PS of 384 ± 1.52 nm, PDI of 0.015 ± 0.011, ZP of −39.2 ± 3.45 mV, EE of 58 ± 2.01% and drug release of 77.3 ± 0.554% and was used for permeation study. The lyophilized ASPs were physically stable, and the FA content of ASPs did not decrease significantly during 3 months of storage at 4 °C. The skin permeation experimental results indicated positive results that successfully developed FA-loaded ASPs have an effective FA permeability rate and better antioxidant and anti-aging effects than the free drug and are useful and effective for improving skin permeation and slowing skin aging with topical applications.