Sustained Release Effect Research Articles

Preparation and evaluation of sustained release pirfenidone-loaded microsphere dry powder inhalation for treatment of idiopathic pulmonary fibrosis

Pirfenidone (PFND) is a recommended oral drug used to treat idiopathic pulmonary fibrosis, but have low bioavailability and high hepatotoxicity. The study, therefore, seeks to improve the therapeutic activities of the drug via increased bioavailability and reduced associated side effects by developing a novel drug delivery system.The electrostatic spray technology was used to prepare a sustained release pirfenidone-loaded microsphere dry powder inhalation with PEG-modified chitosan (PFND-mPEG-CS-MS). The entrapment efficiency, drug loading, and in vitro cumulative drug release rate (at 24 h and with a sustained release effect) of PFND-mPEG-CS-MS were 77.35±3.01%, 11.45±0.64%, and 90.4%, respectively. The Carr's index of PFND-mPEG-CS-MS powder was 17.074±2.163% with a theoretical mass median aerodynamic diameter (MMADt) of 0.99±0.07 μm, and a moisture absorption weight gain rate (Rw) of 4.61±0.72%. The emptying rate, pulmonary deposition rate (fine particle fraction) and actual mass median aerodynamic diameter (MMADa) were 90%∼95%, 48.72±7.04% and 3.10±0.16 μm, respectively. MTT bioassay showed that mPEG-CS-MS (200 μg/mL) had good biocompatibility (RGR = 90.25%) and PFND-mPEG-CS-MS (200 μg/mL) had significant inhibitory activity (RGR = 49.82%) on fibroblast growth. The pharmacokinetic data revealed that the t1/2 (5.02 h) and MRT (10.66 h) of PFND-mPEG-CS-MS were prolonged compared with the free PFND (t1/2, 1.67 h; MRT, 2.71 h). The pharmacodynamic results also showed that the formulated-drug group had slight pathological changes, lower lung hydroxyproline content, and reduced hepatotoxicity compared with the free-drug group. The PFND-mPEG-CS-MS further significantly down-regulated TGF-β cytokines, Collagen I, and α-SMA protein expression levels compared with the free drug. The findings indicated that the PFND-mPEG-CS-MS had a good sustained release effect, enhanced bioavailability, decreased toxicity, and increased anti-fibrotic activities.

Transdermal Delivery of Estradiol Simultaneously Possessing Rapid Release and Sustained Release Effect.

Dissolving microneedle (DMN) has been researched as a drug delivery technology that improves drug molecule transportation through the skin with little discomfort. However, the sluggish drug absorption, poor skin dissolution, and lengthy time lags of DMN have limited its potential uses. The aim of this study was to design a novel DMN system for the administration of the poorly water-soluble drug, estradiol (E2), with fast skin penetration and a stable release rate for a long time. DMN containing E2 emulsion (E2-EM-DMN) and traditional DMN (T-DMN) were prepared. Rat skin was used for penetration test and guinea pig skin was used for skin irritation experiment. The drug release profiles and stability properties of these two kinds of DMNs were also investigated. High performance liquid chromatography was employed to determine the E2 content in DMN. The E2 concentration in rat plasma was achieved by a newly developed liquid chromatography-mass spectrometry method that was fast, reproducible, and specific. The height of E2-EM-DMN and T-DMN was 600μm. The drug loading of the E2-EM-DMN and T-DMN was 667.30 ± 7.21μg/patch and 672.56 ± 6.98μg/patch. E2-EM-DMN possessed enough mechanical strength to penetrate the skin and caused no irritation to the skin. E2-EM-DMN could release the drug more rapidly and more continuously than T-DMN. E2-EM-DMN had good pharmaceutical stability. In summary, the E2-EM-DMN showed reliable quality and superior release performance. Emulsion-embedded DMN is an ideal transdermal delivery system for drugs.

Fabrication of biodegradable hollow microsphere composites made of polybutylene adipate co-terephthalate/polyvinylpyrrolidone for drug delivery and sustained release.

Sustained drug release has attracted increasing interest in targeted drug therapy. However, existing methods of drug therapy suffer drug action time, large fluctuations in the effective concentration of the drug, and the risk of side effects. Here, a biodegradable composite of polybutylene adipate co-terephthalate/polyvinylpyrrolidone (PBAT/PVP) consisting of electrospun hollow microspheres as sustained-released drug carriers is presented. The as-prepared PBAT/PVP composites show faster degradation rate and drug (Erlotinib) release than that of PBAT. Furthermore, PBAT/PVP composites loaded with Erlotinib provide sustained release effect, thus achieving a better efficacy than that after the direct injection of erlotinib due to the fact that the composites allow a high drug concentration in the tumor for a longer period. Hence, this work provides a potential effective solution for clinical drug therapy and tissue engineering using drug microspheres with a sustained release.

Preparation and Properties of Self-Cross-Linking Hydrogels Based on Chitosan Derivatives and Oxidized Sodium Alginate.

A self-cross-linking and biocompatible hydrogel has wide application potential in the field of tissue engineering. In this work, an easily available, biodegradable, and resilient hydrogel was prepared using a self-cross-linking method. This hydrogel was composed of N-2-hydroxypropyl trimethyl ammonium chloride chitosan (HACC) and oxidized sodium alginate (OSA). A stable and reversible cross-linking network was formed by the Schiff base self-cross-linked and hydrogen bonding. The addition of a shielding agent (NaCl) may weaken the intense electrostatic effect between HACC and OSA and solve the problem of flocculation caused by the rapid formation of ionic bonds, which provided an extended time for the Schiff base self-cross-linked reaction for forming a homogeneous hydrogel. Interestingly, the shortest time for the formation of the HACC/OSA hydrogel was within 74 s and the hydrogel had a uniform porous structure and enhanced mechanical properties. The HACC/OSA hydrogel withstood large compression deformation due to improved elasticity. What's more, this hydrogel possessed favorable swelling property, biodegradation, and water retention. The HACC/OSA hydrogels have great antibacterial properties against Staphylococcus aureus and Escherichia coli and demonstrated good cytocompatibility as well. The HACC/OSA hydrogels have a good sustained release effect on rhodamine (model drug). Thus, the obtained self-cross-linked HACC/OSA hydrogels in this study have potential applications in the field of biomedical carriers.

Effect of 3D Food Printing Processing on Polyphenol System of Loaded Aronia melanocarpa and Post-Processing Evaluation of 3D Printing Products.

Aronia melanocarpa polyphenols (AMP) have good nutritional values and functions. This study aimed to explore the printability and storage properties of AM gels in 3D food printing (3DFP). Therefore, 3DFP was performed on a loaded AMP gel system to determine its textural properties, rheological properties, microstructure, swelling degree and storage performance. The results revealed that the best loading AMP gel system to meet the printability requirements of 3DFP processing was AM fruit pulp:methylcellulose:pea albumin: hyaluronic acid = 100:14:1:1. Compared with other ratios and before 3DFP processing, the best loading AMP gel system processed by 3DFP exhibited the lowest deviation of 4.19%, the highest hardness, the highest elasticity, the least adhesion, a compact structure, uniform porosity, difficulty in collapsing, good support, a high degree of crosslinking, and good water retention. Additionally, they could be stored for 14 d at 4 °C. After post-processing, the AMP gel had a favorable AMP release rate and good sustained release effect in gastrointestinal digestion, which conformed to the Ritger-Peppas equation model. The results revealed that the gel system had good printability and applicability for 3D printing; as well, 3DFP products had good storage properties. These conclusions provide a theoretical basis for the application of 3D printing using fruit pulp as a raw material.

Preparation and curing behaviour of microencapsulated curing agents for cold-mixed epoxy asphalt

This study aimed to improve control over the curing behaviour of cold-mixed epoxy asphalt by using a microencapsulated curing agent (2-PZ@PC). Prepared through solvent evaporation, the 2-PZ@PC microcapsules had 2-phenylimidazole as the core material and polycarbonate as the shell material. The research examined the impact of core–shell mass ratio on microcapsule morphology and composition. Various equations, including the kinetics equation, Kissinger equation, Flynn–Wall–Ozawa, and Crane equations, were employed to assess the sustained release effect of 2-PZ@PC microcapsules on epoxy resin curing behaviour. Fluorescence microscopy and viscosity experiments were used to observe the release state of microcapsules and confirm the retardation phenomenon during construction. Optimal 2-PZ@PC microcapsules displayed a smooth spherical morphology and a maximum encapsulation rate of 32 wt% at a 1:1 core–shell ratio. The microencapsulated curing agent effectively regulated cold-mixed epoxy asphalt’s curing behaviour, enhancing retention time control and application reliability.

Preparation and rectal administration of hydroxybutyl chitosan/graphene oxide composite thermosensitive hydrogel

Recently, temperature-sensitive hydrogels have gained great interest as rectal gels. In this study, we selected temperature-sensitive hydroxybutyl chitosan gel (HBC) cross-linked with graphene oxide (GO) to improve biocompatibility. First, modified Hummer and ultrasonic stripping methods were used to synthesize stable GO dispersions. Pingyangmycin (PYM) as the model drug, the optimal drug loading process of GO@PYM was determined by the BBD model using encapsulation rate as the index of investigation. Then, HBC hydrogel was prepared by homogeneous etherification reaction. The 5%(wt) HBC hydrogel's gel time (Tgel) was 36.5 °C and gelation time was 30s. Finally, GO was cross-linked with HBC by hydrogen bonding to form HBC/GO composite hydrogel. Tgel was reduced to 31.7 °C. GO substantially enhanced the mechanical strength of HBC and the stability of HBC/GO structure. HBC/GO@PYM drug loading rate was approximately 8 times higher than HBC@PYM. The results of pharmacokinetic experiments showed that compared with HBC@PYM group, t1/2, MRT0-∞ (mean retention time) and AUC0-∞ (area under the curve) of HBC/GO@PYM group was 1.44, 1.51 and 2.31 times, respectively. HBC/GO effectively prolonged action time of the drug in-vivo by rectal administration, showed good sustained release effect, and significantly improved the bioavailability of PYM. HBC/GO@PYM can be further investigated by rectal administration.

Preparation, characterization, and evaluation of the antitumor effect of kaempferol nanosuspensions.

Kaempferol (KAE) is a naturally occurring flavonoid compound with antitumor activity. However, the low aqueous solubility, poor chemical stability, and suboptimal bioavailability greatly restrict its clinical application in cancer therapy. To address the aforementioned limitations and augment the antitumor efficacy of KAE, we developed a kaempferol nanosuspensions (KAE-NSps) utilizing D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) as a stabilizing agent, screened the optimal preparation process, and conducted a comprehensive investigation of their fundamental properties as well as the antitumor effects in the study. The findings indicated that the particle size was 186.6 ± 2.6nm of the TPGS-KAE-NSps optimized, the shape of which was fusiform under the transmission electron microscope. The 2% (w/v) glucose was used as the cryoprotectant for TPGS-KAE-NSps, whose drug loading content was 70.31 ± 2.11%, and the solubility was prominently improved compared to KAE. The stability and biocompatibility of TPGS-KAE-NSps were favorable and had a certain sustained release effect. Moreover, TPGS-KAE-NSps clearly seen to be taken in the cytoplasm exhibited a stronger cytotoxicity and suppression of cell migration, along with increased intracellular ROS production and higher apoptosis rates compared to KAE in vitro cell experiments. In addition, TPGS-KAE-NSps had a longer duration of action in mice, significantly improved bioavailability, and showed a stronger inhibition of tumor growth (the tumor inhibition rate of high dose intravenous injection group was 68.9 ± 1.46%) than KAE with no obvious toxicity in 4T1 tumor-bearing mice. Overall, TPGS-KAE-NSps prepared notably improved the defect and the antitumor effects of KAE, making it a promising nanodrug delivery system for KAE with potential applications as a clinical antitumor drug.

Soy protein isolate-citrus pectin-gallic acid ternary composite high internal phase Pickering emulsion for delivery of β-carotene: Physicochemical, structural and digestive properties

The structure properties, stability and β-carotene slow-release mechanism of soybean protein isolate-citrus pectin-gallic acid complex (SPI-CP-GA) stabilized high-internal phase Pickering emulsion (HIPPE) were investigated. The results showed that compared with the SPI-CP binary complex, the turbidity of the SPI-CP-GA ternary complex increased from 2.174 ± 0.001 to 3.027 ± 0.001, the surface wettability was increased, the infrared peaks was blue-shifted, changed from hydrophilic to hydrophobic, and the equilibrium interfacial tension of particles increased from 10.77 ± 0.02 mN/m to 13.46 ± 0.03 mN/m, the complex was more stable. When the GA was 2.0 mg/mL, the encapsulation efficiency of β-carotene was higher. With increased GA concentration and oil phase volume fraction (φ), the apparent viscosity and viscoelastic behavior of HIPPE performed well, forming a stable gel network structure. After 30 days of storage, there was no oil separation in the sample group with GA concentration of 2.0 mg/mL and φ = 0.7, and the stability was strong. After gastrointestinal digestion, the particle size of the HIPPE decreased from 13.51 ± 0.86 μm to 7.70 ± 0.68 μm, the free fatty acid (FFA) release rate was 22.03%, and the bioaccessibility of β-carotene was 6.67 ± 0.19%, and the sustained-release effect was obvious. These results indicated that the SPI-CP-GA ternary complex is a potential stabilizer for HIPPE, and providing theoretical guidance for the design of protein-polysaccharide-polyphenol stabilized HIPPE.

Fabrication and drug release behavior of the composite membrane via silk fibroin cross-linked with sodium alginate

ABSTRACT A series of silk fibroin composite membranes were prepared by blending silk fibroin (SF) with sodium alginate (SA) at different ratios. Different contents of polyethylene glycol (PEG) were used as a crosslinking agent to fix the structure of the composite membrane. Water-soluble pazufloxacin mesylate as the model drug was embedded in the composite membrane. The relationship between structure and properties was demonstrated by the sustained-release effect on model drug, and the experimental results revealed that the silk fibroin composite membrane had an excellent function of controlling the release behavior of model drugs, which exhibited pH responsivity to some extent.

Anticancer Effect of STING Agonist-Encapsulated Liposomes on Breast Cancer.

Breast cancer is one of the most common cancers worldwide, posing a serious threat to human health. Recently, innate immunity has become a widely discussed topic in antitumor research. The STING pathway is an important component of innate immunity, and several STING agonists have been developed and applied in antitumor research. Dimeric amidobenzimidazole (diABZI) is one STING agonist and is a nucleotide analog with low serological stability and cell membrane permeability. In this study, we prepared diABZI-encapsulated liposomes (dLNPs) using the ammonium sulfate gradient method. The average particle size of the dLNPs was 99.76 ± 0.230 nm, and the encapsulation efficiency was 58.29 ± 0.53%. Additionally, in vivo and in vitro assays showed that the dLNPs had a sustained-release effect and that the circulation time in vivo was longer than 48 h. The expression of IFN-β and IFN-γ was elevated in mice treated with dLNPs. Moreover, we found that dLNPs can recruit CD8+ T cells to tumor tissue and exert antitumor effects. The dLNPs-treated group showed the most significant efficacy: the average tumor volume was 231.46 mm3, which decreased by 78.16% and 54.47% compared to the PBS group and diABZI group. Meanwhile, the hemolysis rate of the dLNPs was 2%, showing high biocompatibility. In conclusion, dLNPs can effectively suppress tumor growth and possess great potential in breast cancer therapy.

Transdermal administration of ibuprofen-loaded hexagonal liquid crystal gel for enhancement of drug concentration in the uterus: in vitro and in vivo evaluation

Primary dysmenorrhea is a common disease in women, and oral administration of Ibuprofen (IBU) is associated with first-pass effects and gastrointestinal irritation. Here, we developed ibuprofen-loaded hexagonal liquid crystal (IBU HLC) gel for transdermal administration. In this study, the structure of prepared IBU HLC was characterized using polarizing microscopey (PLM) and small angle X ray diffraction (SAXS). In vitro drug release behavior and percutaneous penetration were investigated, and drug transdermal behavior was observed by confocal laser scanning microscope (CLSM). Finally, the pharmacokinetic profile and tissue distribution were investigated after transdermal administration. The PLM and SAXS results showed that the inner structure of IBU HLC was hexagonal phase. Moreover, in vitro release, skin permeation and CLSM demonstrated that IBU HLC had an excellent sustained-release effect, and a good transdermal penetration effect accompanied by the combination of multiple percutaneous routes. Pharmacokinetic studies indicated that IBU entered the blood circulation through abdominal transdermal administration in small amounts, mainly entering the uterus, and had a certain targeting ability. In conclusion, the IBU HLC gel would be a promising sustained-release preparation for transdermal administration to relieve dysmenorrhea with a significant drug concentration in the uterus.

Development, optimization, and in vitro/in vivo evaluation of ranitidine hydrochloride resinate sustained release suspension

Purpose: To prepare ranitidine hydrochloride (RH) sustained-release suspension aimed at improving its safety, effectiveness and convenience of administration. Methods: The RH resinate suspension was prepared using bath method, with a cation- exchange resin as carrier. To obtain an ideal sustained release effect, RH resinates were coated with Eudragit®RS100 using the surface coating method, followed by optimization through a single-factor experiment and response surface analysis. The optimized RH suspension was characterized using accelerated stability test. Moreover, it was pharmacokinetically evaluated in vivo. Results: The optimized RH resin microcapsules showed relative mean deviation between the predicted and measured release values that was < 10 %, (p < 0.05) and demonstrated good reproducibility. Accelerated stability test results showed that the optimized RH suspension exhibited good stability over a period of 6 months (F > 0.9; drug content: 97 – 100 %, drug release: f2 > 50; drug leakage < 0.5 %), with good redispersibility. Results from pharmacokinetics showed that values of Tmax for RH sustained-release suspension and RH common tablet were 4.00 and 2.5 h, respectively (p < 0.05), while the corresponding Cmax values were 2545.78 and 3245.97 ng/mL, respectively (p < 0.05). Results of analysis of AUC0-24 showed that they were equivalent in terms of AUC0-24 (p < 0.05) and bioavailability of 101.05%. Conclusion: The optimized ranitidine hydrochloride (RH) sustained-release suspension has been successfully prepared using ion-exchange resin as a carrier and Eudragit® RS100 as a coating material.

Fabrication of cinnamaldehyde-entrapped ethosome nanoparticles as antimicrobial agent

The aim of this work was to improve the stability and antimicrobial effects of cinnamaldehyde (CA) through the fabrication of ethosomal nanoparticles (CALG-ENPs). Novel formulated CALG-ENPs with a mean size of 103.5 nm and a CA loading of 32.62 mg/g ethosome were obtained with 0.79% CA, 2% lecithin, and 25% ethanol. CALG-ENPs exhibited satisfactory dispersion stability at 4 °C for 25 days under low pHs (>4). The nanoparticles also showed sustained-release effects at 20 °C and 37 °C, in which the retaining amounts of CA were 76.73% and 75.42% after 24 h, respectively, which were remarkably higher than those of free CA (25.68% and 21.12%, respectively). CALG-ENPs exhibited greater antimicrobial activity with a minimum inhibitory concentration and minimum fungicidal concentration of 106.8 and 124.6 μg/mL for Colletotrichum musae, respectively, which were considerably lower than those of free CA (160.2 and 180.0 μg/mL). The fresh-keeping effects of pitaya juice showed 100% inhibition in microbial contamination and effectively avoided oxidation and fading after 14 days. This study indicates that nanoethosome considerably potentiates the antimicrobial efficacy of CA, providing a promising potential for food applications.

MoS2 quantum dots based on lipid drug delivery system for combined therapy against Alzheimer's disease

Pathological pathways of Alzheimer's disease (AD) are criss-crossed, various pathological factors are dynamically correlated and relatively independent, which makes the single-target drug therapy less effective. Therefore, rational use of multiple therapeutic strategies for accurate inhibition of multiple pathological targets are effective to enhance the efficacy of AD therapy. The combination of drug loading and the excellent photothermal conversion property of nanocomposites is highly innovative to combat the two prominent pathological factors of Alzheimer's disease, oxidative stress and amyloid-β-(1–42) (Aβ1-42) deposition caused by reactive oxygen species (ROS) imbalance. Molybdenum disulfide quantum dots (MoS2 QDs) were selected as carriers and functionalized with lipids (MoS2 QDs/lipid) to improve their dispersibility in water, while effectively escaping immune clearance, improving the efficiency of multi-target applications and targeting advantages. The loading of curcumin (MoS2 QDs/lipid-Cur) not only overcomes the disadvantages of poor water solubility and low bioavailability of the drug, but also achieves the function of sustained release and long-term effect. MoS2 QDs/lipid-Cur showed excellent performance in the two therapeutic targets of anti-Aβ1-42 deposition and elimination of ROS in the early stage, and also obtained consistent excellent results in cell experiments. The drug-loaded combined with NIR treatment group significantly reduced Aβ1-42 mediated neurotoxicity. The in vivo photothermal experiment showed that NIR irradiation in the mouse brain can effectively open the blood-brain barrier (BBB) and increase the permeability of the material to the BBB. At the same time, NIR irradiation enriched drug-loaded material in the mouse brain, resulting in a significant increase in the temperature difference between the mice brains. MoS2 QDs/lipid-Cur is an excellent nanocomposite that integrates multiple functions and can be used for multi-target therapy.

Novel “all-in-one” multifunctional gelatin-based film for beef freshness maintaining and monitoring

In this study, a novel multifunctional food packaging was developed by incorporating alizarin (AL) and oregano essential oil Pickering emulsion (OEOP) into a gelatin film matrix. The incorporation of OEOP and alizarin improved the UV–vis resistance property of the film, blocking almost all UV–vis light (decreasing 71.80% to 0.06% at 400 nm). The elongation-at-break (EBA) was 4.02 times of that of gelatin film, indicating the improved mechanical properties of the films. This film showed a significant color change from yellow to purple in the pH range of 3–11 and a considerable sensitivity to ammonia vapor within 4 min, which was attributed to the deprotonation of the alizarin molecule. The film's antioxidant and dynamic antimicrobial capacity was significantly improved owing to the sustained release effect of OEOP. Furthermore, the multifunctional film effectively slowed down the beef spoilage rate and provided real-time visual monitoring of freshness through color changes. Additionally, the color change of the beef quality was linked to the RGB values of the film through a smartphone APP. Overall, this work broadens the possibilities of applications in the food packaging industry for multifunctional food packaging film with preservation and monitoring functions.

Dual-Mechanism Glycolipidpeptide with High Antimicrobial Activity, Immunomodulatory Activity, and Potential Application for Combined Antibacterial Therapy.

Bacterial drug resistance is becoming increasingly serious, and it is urgent to develop effective antibacterial drugs. Antimicrobial peptides (AMPs), as potential candidates against bacteria, have a broad prospect for development. Herein, a series of AMPs with biological characteristics (net positive charge, amphiphilicity, and α-helix), an AXA motif recognized by membrane bound serine protease type I signal peptidases (SPase I), an FLPII motif to reduce hemolysis, and a monosaccharide motif to improve the stability and activity were designed and synthesized, and among which, the glycolipidpeptide GLP6 (glycosylated LP6 lipopeptide) had excellent antibacterial and immunomodulatory activity, good stability and biocompatibility, and excellent biofilm eradication and membrane penetrating activity. The positively charged spherical aggregates formed by self-assembly of GLP6 could encapsulate tetracycline (TC) to form GLP6@TC with a sustained-release effect, which could enhance the sensitivity of bacteria to the antibiotic and realize combined sterilization. The results of acute peritonitis and bacterial keratitis showed that GLP6@TC had a good combined antibacterial effect and the ability to inhibit interleukin-2 (IL-2), which could significantly reduce the inflammatory response while treating bacterial infection, and it had great potential for application. The results of computer molecular docking showed the AXA motif could effectively bind to SPase I, which was consistent with the results of biological experiments. In general, the study could provide a perspective for the design of AMPs and combined antibacterial therapy.

Anti-Inflammatory Salidroside Delivery from Chitin Hydrogels for NIR-II Image-Guided Therapy of Atopic Dermatitis.

Atopic dermatitis (AD) is the most common heterogeneous skin disease. Currently, effective primary prevention approaches that hamper the occurrence of mild to moderate AD have not been reported. In this work, the quaternized β-chitin dextran (QCOD) hydrogel was adopted as a topical carrier system for topical and transdermal delivery of salidroside for the first time. The cumulative release value of salidroside reached ~82% after 72 h at pH 7.4, while in vitro drug release experiments proved that QCOD@Sal (QCOD@Salidroside) has a good, sustained release effect, and the effect of QCOD@Sal on atopic dermatitis mice was further investigated. QCOD@Sal could promote skin repair or AD by modulating inflammatory factors TNF-α and IL-6 without skin irritation. The present study also evaluated NIR-II image-guided therapy (NIR-II, 1000-1700 nm) of AD using QCOD@Sal. The treatment process of AD was monitored in real-time, and the extent of skin lesions and immune factors were correlated with the NIR-II fluorescence signals. These attractive results provide a new perspective for designing NIR-II probes for NIR-II imaging and image-guided therapy with QCOD@Sal.

Regenerative marine waste towards CaCO3 nanoformulation for Alzheimer's therapy

Alzheimer's disorder (AD) is associated with behavioural and cognitive destruction with due respect to the neurological degeneration. Conventional therapeutic approach for treatment of AD using neuroprotective drugs suffered certain limitations such as poor solubility, insufficient bioavailability, adverse side effects at higher dose and ineffective permeability on blood brain barrier (BBB). Development of nanomaterial based drug delivery system helped to overcome these barriers. Hence the present work focused on encapsulating neuroprotective drug citronellyl acetate within CaCO3 nanoparticles to develop neuroprotective CaCO3 nanoformulation (CA@CaCO3 NFs). CaCO3 was derived from marine conch shell waste, while the neuroprotective drug citronellyl acetate was scrutinized by in-silico high throughput screening. In-vitro findings revealed that CA@CaCO3 nanoformulation exhibited enhanced free radical scavenging activity of 92% (IC50 value - 29.27 ± 2.6 μg/ml), AChE inhibition of 95% (IC50 value - 25.6292 ± 1.5 μg/ml) at its maximum dose (100 μg/ml). CA@CaCO3 NFs attenuated the aggregation of β-amyloid peptide (Aβ) and also disaggregated the preformed mature plaques the major risk factor for AD. Overall, the present study reveals that CaCO3 nanoformulations exhibits potent neuroprotective potential when compared to the CaCO3 nanoparticles alone and citronellyl acetate alone due to the sustained drug release and synergistic effect of CaCO3 nanoparticles and citronellyl acetate depicting the fact that CaCO3 can act as promising drug delivery system for treatment of neurodegenerative and CNS related disorders.

Design and Development of Captopril Gastro-Retentive Tablet Using Natural Polymers of Maize and Jowar Plant

Nowadays, the use of natural polymers as an alternative to synthetic gastro-retentive polymers is increasing. Such natural raw materials are highly biocompatible and biodegradable with no or significantly fewer side effects and are economical too. The main aim of this research work was to design a gastro-retentive tablet of Captopril by using Maize Stem Pith (MSP) powder and Jowar Stem Pith (JSP) as novel natural low-density polymers and also to sustain the drug release for up to 12 hours. Our objective behind this research is to prepare the gastro-retentive tablet, evaluate it for floating behavior, and to achieve the sustained release effect for at least 12 hours. The novelty of this research work is that MSP powder and JSP powder possesses low density. Thus, gastro-retentive tablets with a low-density (floating) approach can be prepared at a very lost cost compared to the currently marketed formulation. Gastro-retentive tablets of Captopril were designed by using MSP and JSP powder. Using design-expert® version 13, the formulations were prepared using a 32-complete factorial design. The gastro-retentive tablet showed good floating behavior and dissolution pattern, which sustains the release of the drug for up to 12 hours. The optimization study using a contour plot and response surface plot suggested that formulation R9 is an optimized batch among all batches. The current research indicated that there is an increase in floating time with a corresponding decline in the dissolution rate of the tablet as the concentration of MSP powder and JSP powder increases. The optimized formulation R9 consists of MSP powder and JSP powder at 12% and 8 %, respectively, in combination with HPMC (K-100M), and has proven excellent floating behavior and expected drug release pattern. Therefore, MSP powder and JSP powder could be used as suitable low-density novel polymers to design gastro-retentive tablets of Captopril.