Genistein Co-Amorphous Systems with Amino Acids: An Investigation into Enhanced Solubility and Biological Activity

Exploration of enalapril-lacidipine co-amorphous system with superior dissolution, in vivo absorption and physical stability via incorporated into mesoporous silica

In the present study, enalapril (ENP) was taking as a potential co-former to fabricate co-amorphous system with lacidipine (LCDP). The ENP/LCDP co-amorphous system was firstly prepared with or without mesoporous SiO2 and characterized by DSC, XRD and SEM technologies. The potential molecular interactions were evaluated by FTIR spectrums. Furthermore, the dissolution and pharmacokinetics behavior of various formulations were also carried out. It was demonstrated that the completely co-amorphization was obtained at ENP/LCDP 2:1 molar ratio by the intermolecular interactions between ENP and LCDP. The ENP/LCDP co-amorphous system significantly improve the dissolution rate of LCDP and ENP respectively. Compared to the naked ENP/LCDP co-amorphous system, remarkable enhancement of dissolution rate and bioavailability of model drugs was observed by incorporated the co-amorphous system into mesoporous SiO2, and a superior physical stability was also observed after accelerated study. Raman mapping revealed that the less microstructure phase separation could be the main reason for the better stability in presence of mesoporous SiO2. In conclusion, ENP could be successfully used as a potential co-former to fabricate co-amorphous system with poorly water-soluble drugs and collaborates the co-amorphous with mesoporous SiO2 become a promising strategy to achieve stable amorphous formulation for further enhancement of dissolution rate and bioavailability.

Long-Term Stabilized and Highly Soluble Bezafibrate-Gliclazide Co-Amorphous Binary System

Metabolic syndrome (MS) has a high prevalence, with an estimated one-quarter of the world population affected by this pathological condition. Among the diseases of this syndrome are dysregulation of lipids, hypertension, and insulin resistance. Unfortunately, available drugs in the market used for treating MS, as almost 75% of all drugs, are highly insoluble, presenting a significant demand for strategies to increase their solubility. Taking advantage of the fact that drugs in the amorphous state can provide a solubility enhancement, a new drug-drug co-amorphous (CoA) formulation to potentially simultaneously treat two or more MS conditions was explored, combining the co-formers Bezafibrate (BZT) a lipid-regulating drug, and Gliclazide (GZD) a hypoglycemic agent. A phase diagram was constructed to characterize the binary system's thermal properties, including glass transition temperatures of all compositions studied. The formulations were characterized by FTIR; redshifts of IR bands from 1547 to 1538 cm-1 and 1717 to 1609 cm-1 were observed due to the formation of intermolecular interactions, such as hydrogen bonds. The co-amorphous binary systems lead to an increase in the solubility of both BZT and GZD; specifically, for the composition xBZT = 0.5, the increase was 2.1× for BZT and 1.5 times for GZD while for xBZT = 0.7 an increase of 4× of BZT was achieved. The structural stability of the samples was verified by XRD and DSC, showing long-term stability retention of the amorphous state for more than eight years. The enhanced solubility and stability of the co-amorphous systems make them potential formulations for regulating lipids and lowering glycemia.

Curcumin Solubility and Bioactivity Enhancement Through Amorphization with Tryptophan via Supercritical Fluid Technology

Curcumin, a compound known for its antioxidant and neuroprotective properties, faces challenges due to its low water solubility, which can limit its effectiveness. One effective method to address this issue is through amorphization. Incorporating curcumin into a polymeric matrix to form amorphous solid dispersions is a common approach. Another strategy involves co-amorphous systems, where low-molecular-weight components act as co-formers. A recent innovative approach combines these strategies. This study used tryptophan as a co-former and prepared systems using supercritical fluid technology. The amorphous nature of two systems was confirmed through X-ray powder diffraction: one with 10% curcumin and a polymer, and another with 10% curcumin, a polymer, and tryptophan. Fourier-transform infrared analysis demonstrated molecular interactions among all components in the systems. Scanning electron microscopy revealed that the amorphization process significantly modified the morphology of the powder particles. The ternary system with tryptophan notably increased curcumin solubility by over 300-fold. The amorphous form of curcumin in both systems exhibited significantly higher dissolution rates compared to its crystalline form. The system with tryptophan showed more than a threefold improvement in permeability according to the PAMPA test. The enhanced solubility led to over a sixfold increase in antioxidant activity and a 25-fold improvement in the inhibition of the enzyme butyrylcholinesterase.

Effect of Genistein on Starch Digestion In Vitro and Its Mechanism of Action

The digestive properties of starch are crucial in determining postprandial glycaemic excursions. Genistein, an active phytoestrogen, has the potential to influence starch digestion rates. We investigated the way genistein affected the digestive properties of starch in vitro. We performed enzyme kinetics, fluorescence spectroscopy, molecular docking, and molecular dynamics (MD) simulations for analysing the inhibitory properties of genistein on starch digestive enzymes as well as clarifying relevant mechanism of action. Our findings demonstrated that, following the addition of 10% genistein, the contents of slowly digestible and resistant starches increased by 30.34% and 7.18%, respectively. Genistein inhibited α-amylase and α-glucosidase, with half maximal inhibitory concentrations of 0.69 ± 0.06 and 0.11 ± 0.04 mg/mL, respectively. Genistein exhibits a reversible and non-competitive inhibiting effect on α-amylase, while its inhibition on α-glucosidase is a reversible mixed manner type. Fluorescence spectroscopy indicated that the presence of genistein caused declining fluorescence intensity of the two digestive enzymes. Molecular docking and MD simulations showed that genistein binds spontaneously to α-amylase via hydrogen bonds, hydrophobic interactions, and π-stacking, whereas it binds with α-glucosidase via hydrogen bonds and hydrophobic interactions. These findings suggest the potential for developing genistein as a pharmacologic agent for regulating glycaemic excursions.

Unlocking the potential of flavonoid-based co-crystal and co-amorphous systems

Flavonoids are polyphenolic compounds that have multiple benefits in treating various life-threatening diseases. Despite their diverse pharmacological activities, the market potential of flavonoids is hampered due to their poor solubility and low bioavailability after oral administration. The current review highlights the role of co-crystals and co-amorphous systems (CAMs) in enhancing the solubility, permeability, bioavailability, and therapeutic efficacy of flavonoids. It also explains the significance of flavonoid-based co-formers in the formation of co-crystals and CAMs with other APIs to improve their efficacy. Future perspectives, patented formulations, commercial medications (including their phases of clinical trials), and challenges associated with the use of flavonoid-based co-crystals and CAMs are also mentioned in the review.

Mechanochemical Approach to Obtaining a Multicomponent Fisetin Delivery System Improving Its Solubility and Biological Activity

In this study, binary amorphous solid dispersions (ASDs, fisetin-Eudragit®) and ternary amorphous solid inclusions (ASIs, fisetin-Eudragit®-HP-β-cyclodextrin) of fisetin (FIS) were prepared by the mechanochemical method without solvent. The amorphous nature of FIS in ASDs and ASIs was confirmed using XRPD (X-ray powder diffraction). DSC (Differential scanning calorimetry) confirmed full miscibility of multicomponent delivery systems. FT-IR (Fourier-transform infrared analysis) confirmed interactions that stabilize FIS's amorphous state and identified the functional groups involved. The study culminated in evaluating the impact of amorphization on water solubility and conducting in vitro antioxidant assays: 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)-ABTS, 2,2-diphenyl-1-picrylhydrazyl-DPPH, Cupric Reducing Antioxidant Capacity-CUPRAC, and Ferric Reducing Antioxidant Power-FRAP and in vitro neuroprotective assays: inhibition of acetylcholinesterase-AChE and butyrylcholinesterase-BChE. In addition, molecular docking allowed for the determination of possible bonds and interactions between FIS and the mentioned above enzymes. The best preparation turned out to be ASI_30_EPO (ASD fisetin-Eudragit® containing 30% FIS in combination with HP-β-cyclodextrin), which showed an improvement in apparent solubility (126.5 ± 0.1 µg∙mL-1) and antioxidant properties (ABTS: IC50 = 10.25 µg∙mL-1, DPPH: IC50 = 27.69 µg∙mL-1, CUPRAC: IC0.5 = 9.52 µg∙mL-1, FRAP: IC0.5 = 8.56 µg∙mL-1) and neuroprotective properties (inhibition AChE: 39.91%, and BChE: 42.62%).

Enhanced Antioxidant and Neuroprotective Properties of Pterostilbene (Resveratrol Derivative) in Amorphous Solid Dispersions

In this study, amorphous solid dispersions (ASDs) of pterostilbene (PTR) with polyvinylpyrrolidone polymers (PVP K30 and VA64) were prepared through milling, affirming the amorphous dispersion of PTR via X-ray powder diffraction (XRPD) and differential scanning calorimetry (DSC). Subsequent analysis of DSC thermograms, augmented using mathematical equations such as the Gordon-Taylor and Couchman-Karasz equations, facilitated the determination of predicted values for glass transition (Tg), PTR's miscibility with PVP, and the strength of PTR's interaction with the polymers. Fourier-transform infrared (FTIR) analysis validated interactions maintaining PTR's amorphous state and identified involved functional groups, namely, the 4'-OH and/or -CH groups of PTR and the C=O group of PVP. The study culminated in evaluating the impact of amorphization on water solubility, the release profile in pH 6.8, and in vitro permeability (PAMPA-GIT and BBB methods). In addition, it was determined how improving water solubility affects the increase in antioxidant (ABTS, DPPH, CUPRAC, and FRAP assays) and neuroprotective (inhibition of cholinesterases: AChE and BChE) properties. The apparent solubility of the pure PTR was ~4.0 µg·mL-1 and showed no activity in the considered assays. For obtained ASDs (PTR-PVP30/PTR-PVPVA64, respectively) improvements in apparent solubility (410.8 and 383.2 µg·mL-1), release profile, permeability, antioxidant properties (ABTS: IC50 = 52.37/52.99 μg·mL-1, DPPH: IC50 = 163.43/173.96 μg·mL-1, CUPRAC: IC0.5 = 122.27/129.59 μg·mL-1, FRAP: IC0.5 = 95.69/98.57 μg·mL-1), and neuroprotective effects (AChE: 39.1%/36.2%, BChE: 76.9%/73.2%) were confirmed.

The Study of Amorphous Kaempferol Dispersions Involving FT-IR Spectroscopy

Attenuated total reflection-Mid-Fourier transform-infrared (ATR-Mid-FT-IR) spectroscopy combined with principal component analysis (PCA) has been applied for the discrimination of amorphous solid dispersion (ASD) of kaempferol with different types of Eudragit (L100, L100-55, EPO). The ASD samples were prepared by ball milling. Training and test sets for PCA consisted of a pure compound, physical mixture, and incomplete/complete amorphous solid dispersion. The obtained results confirmed that the range 400-1700 cm-1 was the major contributor to the variance described by PC1 and PC2, which are the fingerprint region. The obtained PCA model selected fully amorphous samples as follows: five for KMP-EL100, two for KMP-EL100-55, and six for KMP-EPO (which was confirmed by the XRPD analysis). DSC analysis confirmed full miscibility of all ASDs (one glass transition temperature). FT-IR analysis confirmed the formation of hydrogen bonds between the -OH and/or -CH groups of KMP and the C=O group of Eudragits. Amorphization improved the solubility of kaempferol in pH 6.8, pH 5.5, and HCl 0.1 N.