Development and Characterization of New Miconazole-Based Microemulsions for Buccal Delivery by Implementing a Full Factorial Design Modeling

This research aimed to develop miconazole-based microemulsions using oleic acid as a natural lipophilic phase and a stabilizer mixture comprising Tween 20 and PEG 400 to solubilize miconazole as an antifungal agent known for its activity in oral candidiasis and to improve its bioavailability. The formulation and preparation process was combined with a mathematical approach using a 23-full factorial plan. Fluid and gel-like microemulsions were obtained and analyzed considering pH, conductivity, and refractive index, followed by extensive analyses focused on droplet size, zeta potential, rheological behavior, and goniometry. In vitro release tests were performed to assess their biopharmaceutical characteristics. Independent variables coded X1-Oleic acid (%, w/w), X2-Tween 20 (%, w/w), and X3-PEG 400 (%, w/w) were analyzed in relationship with three main outputs like mean droplet size, work of adhesion, and diffusion coefficient by combining statistical tools with response surface methodology. The microemulsion containing miconazole base-2%, oleic acid-5%, Tween 20-40%, PEG 400-20%, and water-33% exhibited a mean droplet size of 119.6 nm, a work of adhesion of 71.98 mN/m, a diffusion coefficient of 2.11·10-5 cm2/s, and together with remarked attributes of two gel-like systems formulated with higher oil concentrations, modeled the final optimization step of microemulsions as potential systems for buccal delivery.

In-vitro and In-silico Assessment of Anti-inflammation Properties of Saponarin Extracted from Hordeum Vulgare

BACKGROUND

Hordeum vulgare, commonly known as Barley grass, is a historically significant cultivated plant with profound implications for societies, agricultural sciences, and human nutrition. It has been valued for both sustenance and its potential medicinal properties.

OBJECTIVE

This study aims to comprehensively investigate the medicinal properties of Hordeum vulgare, focusing on its potential therapeutic benefits and anti-inflammatory properties. Additionally, we seek to quantify and compare the phytochemical content of two distinct extracts: Barley Grass Hexane Extract (BGHE) and Barley grass aqueous extract (BGAQ).

METHODS

We quantified the phytochemical contents of BGHE and BGAQ and evaluated their antiinflammatory effects using UV spectroscopy at 560 nm, coupled with the RBC membrane stabilization technique. Subsequently, we conducted in-silico studies to assess the in vitro anti-inflammatory potential of Barley grass leaf extracts.

RESULTS

Both BGHE and BGAQ demonstrated significant inhibitory effects on inflammation compared to the control group. However, BGHE exhibited superior anti-inflammatory efficacy when compared to BGAQ, suggesting its role as a potential anti-inflammatory agent. In-silico studies further supported the anti-inflammatory potential of Barley grass leaf extracts.

CONCLUSION

Hordeum vulgare, or Barley grass, offers a wealth of health benefits, including antiinflammatory, anti-diabetic, anti-cancer, antioxidant, anti-acne, and anti-depressant properties. These properties contribute to improved immunity, reduced cardiovascular disorders, and alleviation of fatigue. The distinct extracts, BGHE and BGAQ, both exhibit promising anti-inflammatory capabilities, but BGHE shows better anti-inflammatory activity. This research sheds light on the therapeutic potential of Barley grass, making it a valuable candidate for further exploration in the field of natural medicine.

Purity and DNA content of AAV capsids assessed by analytical ultracentrifugation and orthogonal biophysical techniques

Development and manufacturing adeno-associated virus (AAV)-based vectors for gene therapy requires suitable analytical methods to assess the quality of the formulations during development, as well as the quality of different batches and the consistency of the processes. Here, we compare biophysical methods to characterize purity and DNA content of viral capsids from five different serotypes (AAV2, AAV5, AAV6, AAV8, and AAV9). For this purpose, we apply multiwavelength sedimentation velocity analytical ultracentrifugation (SV-AUC) to obtain the species' contents and to derive the wavelength-specific correction factors for the respective insert-size. In an orthogonal manner we perform anion exchange chromatography (AEX) and UV-spectroscopy and the three methods yield comparable results on empty/filled capsid contents with these correction factors. Whereas AEX and UV-spectroscopy can quantify empty and filled AAVs, only SV-AUC could identify the low amounts of partially filled capsids present in the samples used in this study. Finally, we employ negative-staining transmission electron microscopy and mass photometry to support the empty/filled ratios with methods that classify individual capsids. The obtained ratios are consistent throughout the orthogonal approaches as long as no other impurities and aggregates are present. Our results show that the combination of selected orthogonal methods can deliver consistent empty/filled contents on non-standard genome sizes, as well as information on other relevant critical quality attributes, such as AAV capsid concentration, genome concentration, insert size length and sample purity to characterize and compare AAV preparations.

Antamanide Analogs as Potential Inhibitors of Tyrosinase

The tyrosinase enzyme, which catalyzes the hydroxylation of monophenols and the oxidation of o-diphenols, is typically involved in the synthesis of the dark product melanin starting from the amino acid tyrosine. Contributing to the browning of plant and fruit tissues and to the hyperpigmentation of the skin, leading to melasma or age spots, the research of possible tyrosinase inhibitors has attracted much interest in agri-food, cosmetic, and medicinal industries. In this study, we analyzed the capability of antamanide, a mushroom bioactive cyclic decapeptide, and some of its glycine derivatives, compared to that of pseudostellarin A, a known tyrosinase inhibitor, to hinder tyrosinase activity by using a spectrophotometric method. Additionally, computational docking studies were performed in order to elucidate the interactions occurring with the tyrosinase catalytic site. Our results show that antamanide did not exert any inhibitory activity. On the contrary, the three glycine derivatives AG9, AG6, and AOG9, which differ from each other by the position of a glycine that substitutes phenylalanine in the parent molecule, improving water solubility and flexibility, showed tyrosinase inhibition by spectrophotometric assays. Analytical data were confirmed by computational studies.

Multi-spectroscopic and molecular docking studies on the interaction of neotame with calf thymus DNA

In this paper, we have studied the in vitro binding of neotame (NTM), an artificial sweetener, with native calf thymus DNA using different methods including spectrophotometric, spectrofluorometric, competition experiment, circular dichroism (CD), and viscosimetric techniques. From the spectrophotometric studies, the binding constant (K_b) of NTM-DNA was calculated to be 2 × 10³ M^-1. The quenching of the intrinsic fluorescence of NTM in the presence of DNA at different temperatures was also used to calculate binding constants (K_b) as well as corresponding number of binding sites (n). Moreover, the obtained results indicated that the quenching mechanism involves static quenching. By comparing the competitive fluorimetric studies with Hoechst 33258, as a known groove probe, and methylene blue, as a known intercalation probe, and iodide quenching experiments it was revealed that NTM strongly binds in the grooves of the DNA helix, which was further confirmed by CD and viscosimetric studies. In addition, a molecular docking method was employed to further investigate the binding interactions between NTM and DNA, and confirm the obtained results.

Stability of Mycotoxins in Individual Stock and Multi-Analyte Standard Solutions

Standard solutions of mycotoxins prepared in RP HPLC solvents from neat standards are usually used for analytical method development. Multi-mycotoxin HPLC-MS/MS methods necessitate stability estimation for the wide spectrum of fungal metabolites. The stability of individual diluted stock standard solutions of mycotoxins in RP-HPLC solvents and multi-analyte HPLC-MS/MS calibrants was evaluated under standard storage and analysis conditions. Individual stock standard solutions of aflatoxins, sterigmatocystin, A- and B-trichothecenes, zearalenone and its analogues, ochratoxin A, fumonisins, Alternaria toxins, enniatins and beauvericin, moniliformin, citrinin, mycophenolic, cyclopiazonic acids and citreoviridin were prepared in RP-HPLC solvents and stored at -18 °C for 14 months. UV-spectroscopy was utilized to monitor the stability of analytes, excluding fumonisins. The gradual degradation of α-, β-zearalenol and α-, β-zearalanol in acetonitrile was detected. Aflatoxins and sterigmatocystin, zearalenone, Alternaria toxins, enniatins and beauvericin, citrinin, mycophenolic, cyclopiazonic acids and citreoviridin can be referred to as stable. The concentration of the majority of trichothecenes should be monitored. Diluted multi-mycotoxin standard in water/methanol (50/50 v/v) solutions acidified with 0.1% formic acid proved to be stable in silanized glass at 23 °C exposed to light for at least 75 h (CV≤10%). An unexpected manifestation of MS/MS signal suppression/enhancement was discovered in the course of multi-mycotoxin standard solution stability evaluation.

Determination of Iron Chelating Agents by Analytical Methods: A Review

Acute iron poisoning and chronic iron overload consequences in significant morbidity and mortality worldwide. Treatment of acute iron poisoning and chronic iron overload can be challenging and care providers are often tackled with management dilemmas. Iron chelating agents are commonly prescribed for patients with iron deficiency anemia. In this review article, different analytical techniques are reported used for qualitative and quantitative analysis of iron chelating agents like, deferiprone, deferoxamine, and deferasirox. Efforts are taken to collect all related articles published till October 2018. This review discusses all analytical methods, its advantages and disadvantages as well as its applications. This article will help you to know about basic analytical techniques as well as advanced hyphenated techniques practiced for determination of iron chelating agents in different matrices. The techniques discussed in this review follow the ICH guidelines for method validation.

σ-Bond Electron Delocalization in Oligosilanes as Function of Substitution Pattern, Chain Length, and Spatial Orientation

Polysilanes are known to exhibit the interesting property of σ-bond electron delocalization. By employing optical spectroscopy (UV-vis), it is possible to judge the degree of delocalization and also differentiate parts of the molecules which are conjugated or not. The current study compares oligosilanes of similar chain length but different substitution pattern. The size of the substituents determines the spatial orientation of the main chain and also controls the conformational flexibility. The chemical nature of the substituents affects the orbital energies of the molecules and thus the positions of the absorption bands.

Studies on the interaction of apigenin with calf thymus DNA by spectroscopic methods

The interaction between apigenin and calf thymus deoxyribonucleic acid (ctDNA) in a pH 7.4 Tris-HCl buffer solution was investigated by UV-Vis spectroscopy, fluorescence spectroscopy, DNA melting techniques, and viscosity measurements. It was found that apigenin molecules could intercalate into the base pairs of DNA, forming a apigenin-DNA complex with a binding constant of K310K=6.4×10(4)Lmol(-1). The thermodynamic parameters enthalpy change (ΔH), entropy change (ΔS) and Gibbs free energy (ΔG) were calculated to be 7.36×10(4)Jmol(-1), 329JK(-1)mol(-1) and -2.84×10(4)Jmol(-1) at 310K, respectively. Hydrophobic interaction was the predominant intermolecular force in stabilizing the apigenin-DNA complex. Thermal denaturation study suggested that the stabilization of the ctDNA helix was increased when the apigenin binding to ctDNA as indicated by the increase in thermal denaturation temperature of ctDNA at around 5.0°C in the presence of apigenin. Spectroscopic techniques together with melting techniques and viscosity determination provided evidences of intercalation mode of binding for the interaction between apigenin and ctDNA.

Differential effects of anti-cancer and anti-hepatitis drugs on liver cystatin

The drug-protein interaction has been the subject of increasing interest over the decades. In the present communication, the interaction of liver cystatin with anti-cancer (adriamycin) and anti-hepatitis (adevofir dipivoxil) drugs was studied by thiol-protease inhibitory assay, UV absorption, fluorescence spectroscopy and circular dichroism (CD). A static type of quenching was observed between the protein and the drug molecules. Binding constant (Ka) of adriamycin to liver cystatin (LC) was found to be 1.08 × 10(6) M(-1). Moreover, binding site number was found to be 2. Importantly, cystatin loses its activity in the presence of adriamycin. However, intrinsic fluorescence studies in the presence of adevofir dipivoxil showed enhancement in the fluorescence intensity suggesting that binding of adevofir to LC caused unfolding of the protein. The unfolding of the test protein was also accompanied by significant loss of inhibitory activity. CD spectroscopy result showed, both adriamycin and adevofir dipivoxil caused perturbation in the secondary structure of liver cystatin. The possible implications of these results will help in combating drug induced off target effects.

σ-Bond electron delocalization of branched oligogermanes and germanium containing oligosilanes

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Oligogermanes and germaoligosilanes isostructural to oligosilanes were synthesized.

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UV absorption data and X-ray diffraction revealed only marginal differences.

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Conformational flexibility is directly reflected in the UV absorption spectrum.

In order to evaluate the influence of germanium atoms in oligo- and polysilanes, a number of oligosilane compounds were prepared where two or more silicon atoms were replaced by germanium. While it can be expected that the structural features of thus altered molecules do not change much, the more interesting question is, whether this modification would have a profound influence on the electronic structure, in particular on the property of σ-bond electron delocalization.

The UV-spectroscopic comparison of the oligosilanes with germanium enriched oligosilanes and also with oligogermanes showed a remarkable uniform picture. The expected bathochromic shift for oligogermanes and Ge-enriched oligosilanes was observed but its extent was very small. For the low energy absorption band the bathochromic shift from a hexasilane chain (256 nm) to a hexagermane chain with identical substituent patterns (259 nm) amounts to a mere 3 nm.