Prescription optimization of gastroretentive furosemide hollow-bioadhesive microspheres via Box-Behnken design: In vitro characterization and in vivo evaluation

Advanced oral drug delivery systems for gastrointestinal targeted delivery: the design principles and foundations

Oral administration has long been considered the most convenient method of drug delivery, requiring minimal expertise and invasiveness. Unlike injections, it avoids discomfort, wound infections, and complications, leading to higher patient compliance. However, the effectiveness of oral delivery is often hindered by the harsh biological barriers of the gastrointestinal tract, which limit the bioaccessibility and bioavailability of drugs. The development of oral drug delivery systems (ODDSs) represents a critical area for the advancement of pharmacotherapy. This review highlights the characteristics and precise targeting mechanisms of ODDSs. It first examines the unique properties of each gastrointestinal compartment, including the stomach, small intestine, intestinal mucus, intestinal epithelial barrier, and colon. Based on these features, it outlines the targeting strategies and design principles for ODDSs aimed at overcoming gastrointestinal barriers to enhance disease treatment. Lastly, the review discusses the challenges and potential future directions for ODDS development, emphasizing their importance for advancing drug delivery technologies and accelerating their future growth.

Current Developments in the Delivery of Gastro-Retentive Drugs

The pharmaceutical industry has expressed a lot of interest in site specific drug delivery & oral controlled release to increase treatment efficiency. The idea of a unique drug delivery system was developed to address several concerns with the physicochemical characteristics of drug molecules and the associated formulations. The use of gastro retentive systems for drug delivery, which focus on site-specific drug release for either systemic or local effects in the stomach, is one of these cutting-edge strategies for lengthening gastric residency time. This approach is especially useful for drugs that have a small window of upper gastro intestinal tract absorption. This review has discussed various gastro-retentive techniques, including floating & non-floating systems. With a focus on the numerous gastro retentive approaches that have lately emerged as the most efficient methods for site specific oral controlled release drug administration, the aim of this study on gastro retentive drug delivery systems was to synthesise the most current findings. We have highlighted the major reasons affecting gastric retention so that you may comprehend the many physiological challenges involved. Next, we discussed the different gastro retentive strategies that have been developed and improved to date, including floating, high density, mucoadhesive, unfoldable, expandable, super porous hydrogel, & magnetic systems. The benefits of gastro retentive medication administration techniques were then thoroughly discussed.

Fabrication of polymeric microspheres for biomedical applications

Polymeric microspheres (PMs) have attracted great attention in the field of biomedicine in the last several decades due to their small particle size, special functionalities shown on the surface and high surface-to-volume ratio. However, how to fabricate PMs which can meet the clinical needs and transform laboratory achievements to industrial scale-up still remains a challenge. Therefore, advanced fabrication technologies are pursued. In this review, we summarize the technologies used to fabricate PMs, including emulsion-based methods, microfluidics, spray drying, coacervation, supercritical fluid and superhydrophobic surface-mediated method and their advantages and disadvantages. We also review the different structures, properties and functions of the PMs and their applications in the fields of drug delivery, cell encapsulation and expansion, scaffolds in tissue engineering, transcatheter arterial embolization and artificial cells. Moreover, we discuss existing challenges and future perspectives for advancing fabrication technologies and biomedical applications of PMs.

pH-Responsive and Mucoadhesive Nanoparticles for Enhanced Oral Insulin Delivery: The Effect of Hyaluronic Acid with Different Molecular Weights

Drug degradation at low pH and rapid clearance from intestinal absorption sites are the main factors limiting the development of oral macromolecular delivery systems. Based on the pH responsiveness and mucosal adhesion of hyaluronic acid (HA) and poly[2-(dimethylamino)ethyl methacrylate] (PDM), we prepared three HA–PDM nano-delivery systems loaded with insulin (INS) using three different molecular weights (MW) of HA (L, M, H), respectively. The three types of nanoparticles (L/H/M-HA–PDM–INS) had uniform particle sizes and negatively charged surfaces. The optimal drug loadings of the L-HA–PDM–INS, M-HA–PDM–INS, H-HA–PDM–INS were 8.69 ± 0.94%, 9.11 ± 1.03%, and 10.61 ± 1.16% (w/w), respectively. The structural characteristics of HA–PDM–INS were determined using FT-IR, and the effect of the MW of HA on the properties of HA–PDM–INS was investigated. The release of INS from H-HA–PDM–INS was 22.01 ± 3.84% at pH 1.2 and 63.23 ± 4.10% at pH 7.4. The protective ability of HA–PDM–INS with different MW against INS was verified by circular dichroism spectroscopy and protease resistance experiments. H-HA–PDM–INS retained 45.67 ± 5.03% INS at pH 1.2 at 2 h. The biocompatibility of HA–PDM–INS, regardless of the MW of HA, was demonstrated using CCK-8 and live–dead cell staining. Compared with the INS solution, the transport efficiencies of L-HA–PDM–INS, M-HA–PDM–INS, and H-HA–PDM–INS increased 4.16, 3.81, and 3.10 times, respectively. In vivo pharmacodynamic and pharmacokinetic studies were performed in diabetic rats following oral administration. H-HA–PDM–INS exhibited an effective hypoglycemic effect over a long period, with relative bioavailability of 14.62%. In conclusion, these simple, environmentally friendly, pH-responsive, and mucoadhesive nanoparticles have the potential for industrial development. This study provides preliminary data support for oral INS delivery.

Hollow mesoporous silica nanoparticles-loaded ion-crosslinked bilayer films with excellent mechanical properties and high bioavailability for buccal delivery

Mucoadhesive buccal films (MBFs) become the most promising buccal mucosal delivery system duo to its advantageous properties, including simple preparation technique and better patient compliance. The mechanical properties and mucoadhesion of MBFs are crucial in their successful performance as well as manufacturing and administration. In this study, we prepared hollow mesoporous silica nanoparticles-loaded ion-crosslinked bilayer films (CCS-PVA-TPP-FSM@HMSNs) using carboxymethyl chitosan (CCS) and polyvinyl alcohol (PVA) for buccal delivery of furosemide (FSM). The FSM-loaded hollow mesoporous silica nanoparticles (FSM@HMSNs) were firstly characterized by SEM, TEM, and nitrogen adsorption/desorption. Then, we constructed an ion-crosslinked network using CCS and PVA employed with the solution casting method, and sodium tripolyphosphate (TPP) was used as a hydrogen bond crosslinking agent. The formulation was optimized through Box-Behnken design, where the impact of the proportion of the ingredients on the quality of the films was evaluated entirely. Herein, folding endurance, swelling, tensile strength, and adhesion force were selected as response variables. Morphology, mechanical, spectroscopic, thermal, and safety of CCS-PVA-TPP-FSM@HMSNs films were also investigated. The release and permeability behaviors of CCS-PVA-TPP-FSM@HMSNs films were evaluated by in vitro drug release, across isolated porcine buccal and TR146 cell model. The CCS-PVA-TPP-FSM@HMSNs films showed outstanding mechanical properties, suitable bioadhesion, high drug loading, significant sustained-release properties, and improved permeability. In pharmacokinetic study with golden hamster models, the relative bioavailability was increased by 191.54%, and the absolute bioavailability was 82.20%. In summary, this study provides evidence that this innovative CCS-PVA-TPP-FSM@HMSNs films could be a promising and industrialized buccal drug delivery system.