A paper-based point-of-care device for the detection of cysteine using gold nanoparticles from whole blood.

We present a colorimetric probe based on polyvinylpyrrolidone-capped gold nanoparticles (PVP-AuNPs) that is sensitive and selective for cysteine (Cys). A microfluidic paper-based analytical device (µ-PAD) with embedded dried PVP-AuNPs at the polyethersulfone (PES) paper surface is used for Cys detection. When thiol molecules attach to PVP-AuNPs in the presence of Cys, they clump together, and this causes the solution's color to shift from red to blue within 5 minutes. The device is capable of detecting Cys levels between 1.0 µM and 50.0 µM with a limit of detection (LOD) of 0.2 µM under optimized conditions. The stability of the µ-PAD was tested for 100 days, demonstrating re-dispersibility to detect Cys levels in blood. Dried PVP-AuNP-µPADs were integrated with blood plasma separation modules for point-of-care (POC) Cys detection. Consequently, the device shows potential as a self-sustaining, quantification platform with a recovery percentage ranging from 98.44 to 111.9 in clinical samples.

PVP/aprepitant microcapsules produced by supercritical antisolvent process.

The supercritical antisolvent (SAS) process was a green alternative to improve the low bioavailability of insoluble drugs. However, it is difficult for SAS process to industrialize with limited production capacity. A coaxial annular nozzle was used to prepare the microcapsules of aprepitant (APR) and polyvinylpyrrolidone (PVP) by SAS with N, N-Dimethylformamide (DMF) as solvent. Meanwhile, the effects of polymer/drug ratio, operating pressure, operating temperature and overall concentration on particles morphology, mean particle diameter and size distribution were analyzed. Microcapsules with mean diameters ranging from 2.04 µm and 9.84 µm were successfully produced. The morphology, particle size, thermal behavior, crystallinity, drug content, drug dissolution and residual amount of DMF of samples were analyzed. The results revealed that the APR drug dissolution of the microcapsules by SAS process was faster than the unprocessed APR. Furthermore, the drug powder collected every hour is in the kilogram level, verifying the possibility to scale up the production of pharmaceuticals employing the SAS process from an industrial point of view.

Molybdesum selenide-based platelet-rich plasma containing carboxymethyl chitosan/polyvinyl pyrrolidone composite antioxidant hydrogels dressing promotes the wound healing.

Excess free radicals at the wound site can cause an inflammatory response, which is not conducive to wound healing. Hydrogels with antioxidant properties can prevent inflammatory storms by scavenging free radicals from the wound site and inhibiting the release of inflammatory factors. In this study, we prepared the carboxymethyl chitosan (CMCS)/polyvinyl pyrrolidone (PVP)/Molybdenum (IV) Selenide (MoSe2), and platelet-rich plasma (PRP) (CMCS/PVP/MoSe2/PRP) hydrogels for accelerating the repair of wounds. In the hydrogels, the MoSe2 can scavenge various free radicals to reduce oxidative stress at the site of inflammation, endowed the hydrogels with antioxidant properties. Interestingly, growth factors released by PRP assisted the tissue repair by promoting the formation of new capillaries. CMCS as a backbone not only showed good biocompatibility and biodegradability but also played a significant role in maintaining the sustained release of growth factors. In addition, incorporating PVP enhanced the tissue adhesion and mechanical properties. The multifunctional composite antioxidant hydrogels have good swelling properties and biodegradability, which is completely degraded within 28 days. Thus, the antioxidant CMCS/PVP/MoSe2/PRP hydrogels provide a new idea for designing ideal multifunctional wound dressings.

Polyvinylpyrrolidone Assisted One-Pot Synthesis of Size-Tunable Cocktail Nanodrug for Multifunctional Combat of Cancer.

Background: The in vivo barriers and multidrug resistance (MDR) are well recognized as great challenges for the fulfillment of antitumor effects of current drugs, which calls for the development of novel therapeutic agents and innovative drug delivery strategies. Nanodrug (ND) combining multiple drugs with distinct modes of action holes the potential to circumvent these challenges, while the introduction of photothermal therapy (PTT) can give further significantly enhanced efficacy in cancer therapy. However, facile preparation of ND which contains dual drugs and photothermal capability with effective cancer treatment ability has rarely been reported. Methods: In this study, we selected curcumin (Cur) and doxorubicin (Dox) as two model drugs for the creation of a cocktail ND (Cur-Dox ND). We utilized polyvinylpyrrolidone (PVP) as a stabilizer and regulator to prepare Cur-Dox ND in a straightforward one-pot method. Results: The size of the resulting Cur-Dox ND can be easily adjusted by tuning the charged ratios. It was noted that both loaded drugs in Cur-Dox ND can realize their functions in the same target cell. Especially, the P-glycoprotein inhibition effect of Cur can synergistically cooperate with Dox, leading to enhanced inhibition of 4T1 cancer cells. Furthermore, Cur-Dox ND exhibited pH-responsive dissociation of loaded drugs and a robust photothermal translation capacity to realize multifunctional combat of cancer for photothermal enhanced anticancer performance. We further demonstrated that this effect can also be realized in 3D multicellular model, which possibly attributed to its superior drug penetration as well as photothermal-enhanced cellular uptake and drug release. Conclusion: In summary, Cur-Dox ND might be a promising ND for better cancer therapy.

Bioinspired Photoelectronic Synergy Coating with Antifogging and Antibacterial Properties.

Optically transparent glass with antifogging and antibacterial properties is in high demand for endoscopes, goggles, and medical display equipment. However, many of the previously reported coatings have limitations in terms of long-term antifogging and efficient antibacterial properties, environmental friendliness, and versatility. In this study, inspired by catfish and sphagnum moss, a novel photoelectronic synergy antifogging and antibacterial coating was prepared by cross-linking polyethylenimine-modified titanium dioxide (PEI-TiO2), polyvinylpyrrolidone (PVP), and poly(acrylic acid) (PAA). The as-prepared coating could remain fog-free under hot steam for more than 40 min. The experimental results indicate that the long-term antifogging properties are due to the water absorption and spreading characteristics. Moreover, the organic-inorganic hybrid of PEI and TiO2 was first applied to enhance the antibacterial performance. The Staphylococcus aureus and the Escherichia coli growth inhibition rates of the as-prepared coating reached 97 and 96% respectively. A photoelectronic synergy antifogging and antibacterial mechanism based on the positive electrical and photocatalytic properties of PEI-TiO2 was proposed. This investigation provides insight into designing multifunctional bioinspired surface materials to realize antifogging and antibacterial that can be applied to medicine and daily lives.

Implications of Low-concentration Polymer on the Physical Stability of Glassy Griseofulvin: Role of the Segmental Mobility.

Crystallization of amorphous pharmaceutical solids are widely reported to be affected by the addition of polymer, while the underlying mechanism require deep study. Herein, crystal growth behaviors of glassy griseofulvin (GSF) doped with various 1% w/w polymer were systematically studied. From the molecular structure, GSF cannot form the hydrogen bonding interactions with the selected polymer poly(vinyl acetate), polyvinyl pyrrolidone (PVP), 60:40 vinyl pyrrolidone-vinyl acetate copolymer (PVP/VA 64), and poly(ethylene oxide) (PEO). 1% w/w polymer exhibited weak or no detectable effects on the glass transition temperature (Tg) of GSF. However, crystal growth rates of GSF was altered from 4.27-fold increase to 2.57-fold decrease at 8 ℃ below Tg of GSF. Interestingly, the ability to accelerate and inhibit the growth rates of GSF crystals correlated well with Tg of polymer, indicating the controlling role of segmental mobility of polymer. Moreover, ring-banded growth of GSF was observed in the polymer-doped systems. Normal compact bulk and ring-banded crystals of GSF were both characterized as the thermodynamically stable form I. More importantly, formation of ring-banded crystals of GSF can significantly weaken the inhibitory effects of polymer on the crystallization of glassy GSF.

Fluorescence lifetime imaging and phasor analysis of intracellular porphyrinic photosensitizers applied with different polymeric formulations.

The fluorescence lifetime of a porphyrinic photosensitizer (PS) is an important parameter to assess the aggregation state of the PS even in complex biological environments. Aggregation-induced quenching of the PS can significantly reduce the yield of singlet oxygen generation and thus its efficiency as a medical drug in photodynamic therapy (PDT) of diseased tissues. Hydrophobicity and the tendency to form aggregates pose challenges on the development of efficient PSs and often require carrier systems. A systematic study was performed to probe the impact of PS structure and encapsulation into polymeric carriers on the fluorescence lifetime in solution and in the intracellular environment. Five different porphyrinic PSs including chlorin e6 (Ce6) derivatives and tetrakis(m-hydroxyphenyl)-porphyrin and -chlorin were studied in free form and combined with polyvinylpyrrolidone (PVP) or micelles composed of triblock-copolymers or Cremophor. Following incubation of HeLa cells with these systems, fluorescence lifetime imaging combined with phasor analysis and image segmentation was applied to study the lifetime distribution in the intracellular surrounding. The data suggest that for free PSs, the structure-dependent cell uptake pathways determine their state and emission lifetimes. PS localization in the plasma membrane yielded mostly monomers with long fluorescence lifetimes whereas the endocytic pathway with subsequent lysosomal deposition adds a short-lived component for hydrophilic anionic PSs. Prolonged incubation times led to increasing contributions from short-lived components that derive from aggregates mainly localized in the cytoplasm. Encapsulation of PSs into polymeric carriers led to monomerization and mostly fluorescence emission decays with long fluorescence lifetimes in solution. However, the efficiency depended on the binding strength that was most pronounced for PVP. In the cellular environment, PVP was able to maintain monomeric long-lived species over prolonged incubation times. This was most pronounced for Ce6 derivatives with a logP value around 4.5. Micellar encapsulation led to faster release of the PSs resulting in multiple components with long and short fluorescence lifetimes. The hydrophilic hardly aggregating PS exhibited a mostly stable invariant lifetime distribution over time with both carriers. The presented data are expected to contribute to optimized PDT treatment protocols and improved PS-carrier design for preventing intracellular fluorescence quenching. In conclusion, amphiphilic and concurrent hydrophobic PSs with high membrane affinity as well as strong binding to the carrier have best prospects to maintain their photophysical properties in vivo and serve thus as efficient photodynamic diagnosis and PDT drugs.

A multifunctional cascade enzyme system for enhanced starvation/chemodynamic combination therapy against hypoxic tumors.

Starvation therapy has shown promise as a cancer treatment, but its efficacy is often limited when used alone. In this work, a multifunctional nanoscale cascade enzyme system, named CaCO3@MnO2-NH2@GOx@PVP (CMGP), was fabricated for enhanced starvation/chemodynamic combination cancer therapy. CMGP is composed of CaCO3 nanoparticles wrapped in a MnO2 shell, with glucose oxidase (GOx) adsorbed and modified with polyvinylpyrrolidone (PVP). MnO2 decomposes H2O2 in cancer cells into O2, which enhances the efficiency of GOx-mediated starvation therapy. CaCO3 can be decomposed in the acidic cancer cell environment, causing Ca2+ overload in cancer cells and inhibiting mitochondrial metabolism. This synergizes with GOx to achieve more efficient starvation therapy. Additionally, the H2O2 and gluconic acid produced during glucose consumption by GOx are utilized by MnO2 with catalase-like activity to enhance O2 production and Mn2+ release. This process accelerates glucose consumption, reactive oxygen species (ROS) generation, and CaCO3 decomposition, promoting the Ca2+ release. CMGP can alleviate tumor hypoxia by cycling the enzymatic cascade reaction, which increases enzyme activity and combines with Ca2+ overload to achieve enhanced combined starvation/chemodynamic therapy. In vitro and in vivo studies demonstrate that CMGP has effective anticancer abilities and good biosafety. It represents a new strategy with great potential for combined cancer therapy.

Strong, Tough, and Biocompatible Poly(vinyl alcohol)-Poly(vinylpyrrolidone) Multiscale Network Hydrogels Reinforced by Aramid Nanofibers.

Poly(vinyl alcohol) (PVA) hydrogels are water-rich, three-dimensional (3D) network materials that are similar to the tissue structure of living organisms. This feature gives hydrogels a wide range of potential applications, including drug delivery systems, articular cartilage regeneration, and tissue engineering. Due to the large amount of water contained in hydrogels, achieving hydrogels with comprehensive properties remains a major challenge, especially for isotropic hydrogels. This study innovatively prepares a multiscale-reinforced PVA hydrogel from molecular-level coupling to nanoscale enhancement by chemically cross-linking poly(vinylpyrrolidone) (PVP) and in situ assembled aromatic polyamide nanofibers (ANFs). The optimized ANFs-PVA-PVP (APP) hydrogels have a tensile strength of ≈9.7 MPa, an elongation at break of ≈585%, a toughness of ≈31.84 MJ/m3, a compressive strength of ≈10.6 MPa, and a high-water content of ≈80%. It is excellent among all reported PVA hydrogels and even comparable to some anisotropic hydrogels. System characterizations show that those performances are attributed to the particular multiscale load-bearing structure and multiple interactions between ANFs and PVA. Moreover, APP hydrogels exhibit excellent biocompatibility and a low friction coefficient (≈0.4). These valuable performances pave the way for broad potential in many advanced applications such as biological tissue replacement, flexible wearable devices, electronic skin, and in vivo sensors.

Influence of oligonucleotides structures for separation of diastereomers by capillary electrophoresis method using polyvinylpyrrolidone 1,300,000.

In the field of oligonucleotides drug discovery, phosphorothioate (PS) modification has been recognized as an effective tool to overcome the nuclease digestion, and generates 2n of possible diastereomers, where n equals the number of PS linkages. However, it is also well known that differences in drug efficacy and toxicity are caused by differences in stereochemistry of oligonucleotides. Therefore, the development of a high-resolution analytical method that enables stereo discrimination of oligonucleotides is desired. Under this circumstance, capillary electrophoresis (CE) using polyvinylpyrrolidone (PVP) is considered as one of the useful tools for the separation analysis of diastereomers. In this study, we evaluated the several oligonucleotides with the structural diversities in order to understand the separation mechanism of the diastereomers by CE. Especially, five kinds of 2'-moieties were deeply examined by CE with PVP 1,300,000 polymer solution. We found that different trend of the peak shapes and the peak resolution were observed among these oligonucleotides. For example, the better peak resolution was observed in 6 mer PS3-DNA compared to the rigid structure of 6 mer PS3-LNA. As for this reason, the computational simulation revealed that difference of accessible surface area caused by the steric structure of thiophosphate in each oligonucleotide is one of the key attributes to explain the separation of the diastereomers. In addition, we achieved the separation of sixteen peak tops of the diastereomers in 6 mer PS4-DNA, and the complete separation of fifteen diastereomers in 6 mer PS4-RNA. These knowledge for the separation of the diastereomers by CE will be expected to the quality control of the oligonucleotide drugs.

Electrosprayed Eudragit RL100 nanoparticles with Janus polyvinylpyrrolidone patches for multiphase release of paracetamol.

Advanced nanotechniques and the corresponding complex nanostructures they produce represent some of the most powerful tools for developing novel drug delivery systems (DDSs). In this study, a side-by-side electrospraying process was developed for creating double-chamber nanoparticles in which Janus soluble polyvinylpyrrolidone (PVP) patches were added to the sides of Eudragit RL100 (RL100) particles. Both sides were loaded with the poorly water-soluble drug paracetamol (PAR). Scanning electron microscope results demonstrated that the electrosprayed nanoparticles had an integrated Janus nanostructure. Combined with observations of the working processes, the microformation mechanism for creating the Janus PVP patches was proposed. XRD, DSC, and ATR-FTIR experiments verified that the PAR drug was present in the Janus particles in an amorphous state due to its fine compatibility with the polymeric matrices. In vitro dissolution tests verified that the Janus nanoparticles were able to provide a typical biphasic drug release profile, with the PVP patches providing 43.8 ± 5.4% drug release in the first phase in a pulsatile manner. In vivo animal experiments indicated that the Janus particles, on one hand, could provide a faster therapeutic effect than the electrosprayed sustained-release RL100 nanoparticles. On the other hand, they could maintain a therapeutic blood drug concentration for a longer period. The controlled release mechanism of the drug was proposed. The protocols reported here pioneer a new process-structure-performance relationship for developing Janus-structure-based advanced nano-DDSs.

Myricetin Amorphous Solid Dispersions-Antineurodegenerative Potential.

Our research aimed to develop an amorphous solid dispersion (ASD) of myricetin (MYR) with Polyvinylpyrrolidone K30 (PVP30) to enhance its solubility, dissolution rate, antioxidant, and neuroprotective properties. Employing a combination of solvent evaporation and freeze drying, we successfully formed MYR ASDs. XRPD analysis confirmed complete amorphization in 1:8 and 1:9 MYR-PVP weight ratios. DSC thermograms exhibited a single glass transition (Tg), indicating full miscibility. FT-IR results and molecular modeling confirmed hydrogen bonds stabilizing MYR's amorphous state. HPLC analysis indicated the absence of degradation products, ensuring safe MYR delivery systems. Solubility, dissolution rate (pH 1.2 and 6.8), antioxidant (ABTS, DPPH, CUPRAC, and FRAP assays), and in vitro neuroprotective activities (inhibition of cholinesterases: AChE and BChE) were significantly improved compared to the pure compound. Molecular docking studies revealed that MYR had made several hydrogen, hydrophobic, and π-π stacking interactions, which could explain the compound's potency to inhibit AChE and BChE. MYR-PVP 1:9 w/w ASD has the best solubility, antioxidant, and neuroprotective activity. Stability studies confirmed the physical stability of MYR-PVP 1:9 w/w ASD immediately after dissolution and for two months under ambient conditions. Our study showed that the obtained ASDs are promising systems for the delivery of MYR with the potential for use in alleviating the symptoms of neurodegenerative diseases.

Formulation and evaluation of dissolving microneedle for transdermal delivery of piperine: the effect of polymers concentration.

This research aims to develop the formulation of Dissolving Microneedle Piperine (DMNs PIP) and evaluate the effect of polymer concentration on characterisation and permeation testing results in ex vivo. DMNs PIP were prepared from varying concentrations of piperine (PIP) (10, 15, and 20% w/w) and polymers of polyvinyl alcohol (PVA): Polyvinyl pyrrolidone (30:60 and 60:25), respectively. Then the morphological evaluation of the formula was carried out, followed by mechanical strength testing. Furthermore, the density, LOD, and weight percentage of piperine in the dried microneedle were calculated and the determination of volume, needle weight and piperine weight and analysed. Ex vivo testing, X-Ray Diffraction, FTIR and hemolysis tests were carried out. PIP with PVA and PVP (F1) polymers produced DMN with mechanical strength (8.35 ± 0.11%) and good penetration ability. In vitro tests showed that the F1 polymer mixture gave good penetration (95.02 ± 1.42 µg/cm2), significantly higher than the F2, F3, F4, and F5 polymer mixtures. The DMNs PIP characterisation results through XRD analysis showed a distinctive peak in the 20-30 region, indicating the presence of crystals. The FTIR study showed that the characteristics of piperine found in DMNs PIP indicated that piperine did not undergo interactions with polymers. The results of the ex vivo study through DMNs PIP hemolytic testing showed no hemolysis occurred, with the hemolysis index below the 5% threshold reported in the literature. These findings indicate that DMNs PIP is non-toxic and safe to use as alternative for treating inflammation.

Hydrophilic and hydrophobic drug release from core (polyvinylpyrrolidone)-sheath (ethyl cellulose) pressure-spun fibers.

A core-sheath structure is one of the methods developed to overcome the challenges often faced when using monolithic fibers for drug delivery. In this study, fibers based on polyvinylpyrrolidone (core) and ethyl cellulose (sheath) were successfully produced using a novel core-sheath pressure-spinning process. For comparison, these two polymers were also processed into as blend fibers. All samples were then investigated for their performances in releasing water-soluble ampicillin (AMP) and poorly water-soluble ibuprofen (IBU) model drugs. Scanning electron,digital and confocal microscopy confirmed that fibers with a core-sheath structure were successfully made. Fourier transform infrared spectroscopy showed the success of the pressure-spinning technique in encapsulating AMP/IBU in all fiber samples. Compared to blend fibers, the core-sheath fibers had better performance in encapsulating both water-soluble and poorly water-soluble drugs. Moreover, the core-sheath structure was able to reduce the initial burst release and provided a better sustained release profile than the blend fiber analog. In conclusion, the pressure-spinning method was capable of producing core-sheath and blend fibers that could be used for the loading of either hydrophilic or hydrophobic drugs for controlled drug delivery systems.

Fabrication of biodegradable and antibacterial films of chitosan/polyvinylpyrrolidone containing Eucalyptus citriodora extracts.

The main objective of this work is to develop biodegradable active films through the combination of the extracts with different solvents sourced from Eucalyptus citriodora leaves, with films made of chitosan (Cs) and polyvinylpyrrolidone (PVP). Chromatographic profiling investigations were carried out to examine the antibacterial characteristics of E. citriodora extracts before their direct incorporation into the polymer films. At this point, the potent antimicrobial properties of the phenol compounds and bioactive components demonstrated an antibacterial activity that was particularly noticeable at a hexane resolution. Different morphological characteristics were seen on films made from these solvent extracts, such as Cs/PVP-AE, Cs/PVP-EAE, and Cs/PVP-HE, when scanning electron microscopy was used. Numerous other outcomes of all the interactions between the extract particles and the film were shown by the pores defined by the Cs/PVP film's porous nature. The addition of the extracts, either alone or in combination, greatly enhanced the Cs/NC/PVP films' mechanical characteristics. It has also been shown that adding plant extracts greatly increased the antibacterial activity of these films. These findings reveal that Cs/PVP films loaded with extract may be utilized as more environmentally acceptable substitutes for possible food packaging application by increasing shelf life of food products.

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.

Fabrication and In-Vivo Evaluation of Polyvinyl pyrrolidone/Poloxamer 188 Hybrid Nanofibers of Deflazacort.

The superior flexibility, efficient drug loading, high surface-to-volume ratio, ease of formulation, and cost-controlled production are considered exceptional advantages of nanofibers (NFs) as a smart delivery system. Deflazacort (DEF) is an anti-inflammatory and immunosuppressant agent. It is categorized as a poorly soluble class II drug. In this study, DEF-loaded polymeric nanofibrous using the electrospinning technique mats, Polyvinyl pyrrolidone (PVP) with or without Poloxamer 188 (PX) were used as mat-forming polymers. Microscopical imaging, drug content (%), and in vitro dissolution studies were conducted for all NFs formulae (F1-F7). All NFs improved the DEF dissolution compared to the unprocessed form, with the superiority of the PVP/PX hybrid. The optimized formula (F7) exhibited an average diameter of 655.46 ± 90.4 nm and % drug content of 84.33 ± 5.58. The dissolution parameters of DEF loaded in PVP/PX NFs (F7) reflected a release of 95.3 % ± 3.1 and 102.6 % ± 1.7 after 5 and 60 min, respectively. NFs (F7) was investigated for drug-polymer compatibility using Fourier-Transform Infrared Spectroscopy (FTIR), Powder X-ray diffraction analysis (PXRD), and Differential Scanning Calorimetry (DSC). In vivo anti-inflammatory study employing male Sprague-Dawley rats showed a significant reduction of rat paw edema for F7 (p < 0.05) compared with unprocessed DEF with a normal epidermal and dermal skin structure comparable to the healthy negative control. Immunohistochemical and morphometric data displayed similarities between the immune reaction of F7 and the negative healthy control. The finding of this work emphasized that DEF loaded in PVP/PX NFs could be considered a useful strategy for enhancing the therapeutic performance of DEF.

The Fabrication, Drug Loading, and Release Behavior of Porous Mannitol.

Porous materials are widely used as an effective strategy for the solubilization of insoluble drugs. In order to improve the solubility and bioavailability of low water-solubility drugs, it is necessary to prepare porous materials. Mannitol is one of the most popular excipients in food and drug formulations. In this study, porous mannitol was investigated as a drug carrier for low water solubility drugs. Its fabrication, drug loading, and drug release mechanisms were investigated. Porous mannitol was fabricated using the co-spray-antisolvent process and utilizing polyvinylpyrrolidone K30 (PVP K30) as the template agent. Porous mannitol particles were prepared by changing the proportion of the template agent, spraying the particles with mannitol, and eluting with ethanol in order to regulate their pore structure. In subsequent studies, porous mannitol morphology and characteristics were determined systematically. Furthermore, curcumin and ibuprofen, two poorly water-soluble drugs, were loaded into porous mannitol, and their release profiles were analyzed. The results of the study indicated that porous mannitol can be prepared using PVP K30 as a template and that the amount of template agent can be adjusted in order to control the structure of the porous mannitol. When the template agent was added in amounts of 1%, 3%, and 5%, the mannitol pore size increased by 167.80%, 95.16%, and 163.98%, respectively, compared to raw mannitol. Molecular docking revealed that mannitol and drugs are adsorbents and adhere to each other by force interaction. The cumulative dissolution of curcumin and ibuprofen-loaded porous mannitol reached 69% and 70%, respectively. The release mechanism of curcumin and ibuprofen from drug-loaded mannitol was suitable for the Korsmeyer-Peppas kinetic model. In summary, the co-spray-antisolvent method proved effective in fabricating porous materials rapidly, and porous mannitol had a remarkable effect on drug solubilization. The results obtained are conducive to the development of porous materials.

Drug content determination of low-dosed hot-melt extruded filaments using Raman spectroscopy.

The aim of this study was to evaluate the suitability of a non-disruptive Raman spectroscopic method to quantify drug concentrations below 5 w% within a polymer matrix produced by hot-melt extrusion (HME). For calibration, praziquantel (PZQ)-polyvinylpyrrolidone-vinylacetat-copolymer (PVP-VA) mixtures were extruded. By focusing the laser light of the Raman probe to a diameter of 1 mm and implementing a self-constructed filament holder, the signal-to-noise (S/N) ratio could be reduced considerably. The obtained Raman spectra show quite high fluorescence, which is likely to be caused by dissolved pharmaceutical active ingredient (API) in the polymer matrix. For content determination, HPLC analysis was conducted as a reference method using the same filament segments. A partial least squares (PLS) model, regressing the PZQ concentrations from HPLC method analysis versus the off-line collected Raman spectra, was developed. The linear correlation for a suitable extrusion run for the production of low-dosed filaments (extrusion 1, two kneading zones) is acceptable (R2 = 0.9915) while the correlation for a extrusion set-up with low miscibility (extrusion 2; without kneading zone) is unacceptable (R2 = 0.5349). The predictive performance of the calibration model from extrusion 1 is rated by the root mean square error of estimation (RMSEE), which was 0.08%. This calibration can now be used to validate the content of low-dosed filaments during HME.

Formulation and characterization of glipizide solid dosage form with enhanced solubility.

Glipizide, a poor water-soluble drug belongs to BCS class II. The proposed work aimed to enhance the solubility of glipizide by preparing solid dispersions, using polyvinyl pyrrolidone (PVP) and polyethylene glycol (PEG). Solvent evaporation method was used for the preparation of glipizide solid dispersions. Solid dispersions were prepared in four different drug-to-polymer ratios i.e. 1:1, 1:2, 1:3 and 1:4. Mainly effect of three polymers (PVP K30, PVP K90 and PEG 6000) was evaluated on the solubility and dissolution of glipizide. The in-vitro dissolution of all prepared formulations was performed under pH 6.8 at 37°C using USP type II apparatus. In-vitro dissolution results revealed that the formulations having high concentrations of the polymer showed enhanced solubility. Enhancements in the solubility and rate of dissolution of the drug were noted in solid dispersion formulations compared to the physical blends and pure drug. Solid dispersions containing polyvinyl pyrrolidone exhibited a more favorable pattern of drug release compared to the corresponding solid dispersions with PEG. An increase in the maximum solubility of the drug within the solid dispersion systems was observed in all instances. Two solid dispersion formulations were optimized and formulated into immediate-release tablets, which passed all the pharmacopoeial and non-pharmacopoeial tests. Fourier transformed Infrared (FTIR) spectroscopy X-ray diffraction (XRD) and Differential scanning calorimetry (DSC) were used to indicate drug: polymer interactions in solid state. Analysis of the solid dispersion samples through characterization tests indicated the compatibility between the drug and the polymer.