Drug Delivery Letters - Online First

Hydrogel-based drug delivery systems have emerged as promising platforms for targeted anti-cancer therapies due to their biocompatibility, controlled drug release profiles, and ability to localize treatment within tumor tissues. These hydrophilic polymer networks facilitate prolonged and site-specific delivery of therapeutic agents, thereby enhancing efficacy while minimizing systemic side effects. Recent advancements in materials science have led to the development of smart hydrogels that respond to tumour-specific stimuli—such as pH, temperature, redox conditions, and enzymatic activity—enabling precise spatiotemporal drug release within the tumor microenvironment. This review explores the design and application of such hydrogel systems, including stimuli-responsive platforms, targeted ligand incorporation, and nanocomposite formulations capable of co-delivering therapeutics and imaging agents. Innovative features such as injectability, self-healing capacity, and shape adaptability further enhance clinical utility by conforming to irregular tumor geometries. Preclinical findings demonstrate improved therapeutic outcomes and safety profiles, and early-phase clinical trials suggest strong potential for integration into personalized cancer treatment regimens. Overall, hydrogel-based delivery systems represent a versatile and minimally invasive approach for next-generation oncology therapies, offering multifunctional capabilities tailored to patient- and tumour-specific requirements.

Liposomes have emerged as flexible and effective nanocarriers for drug delivery, gene therapy, and diagnostics due to their biocompatibility, ability to encapsulate both hydrophilic and hydrophobic compounds, and controlled release properties. Recent advances in liposome production have significantly increased their therapeutic potential, leading to higher drug-loading efficiency, improved targeting capabilities, and greater stability. Traditional technologies, such as thin-film hydration and reverse-phase evaporation, are widely used but suffer from batch-to-batch variability and limited scalability. Microfluidics, freeze-drying methods, and ethanol injection have overcome these restrictions by providing more control over liposome size, polydispersity, and encapsulation efficiency. Microfluidic technology, in particular, enables the precise, repeatable manufacturing of liposomes with narrow size distributions, which is crucial for targeted delivery in nanomedicine.

Furthermore, surface modification approaches such as PEGylation and ligand conjugation have enhanced liposome stability, enabled tissue-specific targeting, minimized off-target effects, and improved therapeutic efficacy. In addition, advances in stimuli-responsive liposomes, which release their payload in response to environmental cues like as pH, temperature, or enzymes, have created new opportunities for site-specific drug administration. Despite these advances, challenges remain in large-scale manufacture, long-term stability, and regulatory approval for therapeutic uses. Ongoing research focused on optimizing preparation methods and enhancing liposome biocompatibility and targeting efficiency holds considerable promise for their future use in precision medicine and tailored treatments.

Magnetic nanoparticles have become adaptable tools with multifaceted uses in different areas of science and technology. The review overviews recent developments in magnetic nanoparticle research, synthesis, and applications, emphasizing their promise in biomedicine, environmental remediation, and energy storage. The paper discusses the speciality of magnetic nanoparticles in possessing a large surface area-to-volume ratio, super-paramagnetism, and biocompatibility, rendering them extremely useful in targeted drug delivery, magnetic resonance imaging, and hyperthermia therapy. The latest advances in synthesis techniques, especially the transition toward environmentally friendly biological methods, are reviewed. It also highlights the obstacles facing the production of Magnetic nanoparticles, including the need to standardize size distribution, increase targeting effectiveness and preserve prolonged stability in biological systems. This review also focused on new applications in neuroscience, gene therapy, and combination therapies, demonstrating that magnetic nanoparticles are multifunctional. Magnetic nanoparticles offer tremendous potential for use in medical applications such as therapeutic targeting and tracking, and environmental technologies, and their integration with other advanced technologies holds great promise for boosting their applications in personalized medicine and environmental technologies. However, progress has also come with challenges ranging from scaling up production to harmonizing evaluation processes and ensuring safety. Magnetic nanoparticles will play an increasingly important role in developing solutions to some of the world's most significant challenges, from medicine to energy to environmental sustainability. They will only further facilitate a better, more technologically advanced future.

The Gastro-Retentive Drug Delivery System (GRDDS) is an innovative method designed to enhance oral drug delivery by delaying the time that medications remain in the stomach. GRDDS addresses the limitations of conventional oral DDS, such as rapid gastric emptying and the low bioavailability of some medications. By maintaining the medication in the stomach for prolonged periods, GRDDS enables improved therapeutic outcomes and sustained drug release. This document explores the physiology and anatomy of the stomach, factors influencing gastric retention, suitable drug candidates, and types of drug delivery systems, including floating, swelling, high-density systems, etc. The advancement of nanotechnology, combination polymers, and stimuli-responsive materials offers future perspectives for further enhancing the efficacy of GRDDS. The system has shown promise in treating diseases such as peptic ulcers, diabetes, and Helicobacter pylori infections, improving drug delivery to systemic as well as local sites. This review highlights that Gastro-Retentive Drug Delivery Systems (GRDDS) effectively improve drug absorption and enhance treatment outcomes. Integrating different strategies with emerging technologies has the potential to further increase their effectiveness and provide greater benefits to patients.

Precision medicine seeks to transform healthcare by offering customized care based on a person's lifestyle, environment, and genetic makeup. Precision medicine has expanded its potential by combining cutting-edge targeted drug delivery systems with gene editing technologies like CRISPR-Cas9, enabling unmatched specificity and efficacy in treating complex disorders. This review examines how these two innovative methods work together, highlighting their impact on tailored therapies. Using gene editing technologies, genetic material can be precisely altered to provide therapeutic solutions for cancer, hereditary disorders, and other genetically based ailments. One major challenge remains the efficient delivery of gene-editing tools to target cells and tissues. Targeted drug delivery systems, such as polymeric carriers, lipid nanoparticles, and nanocarriers, address the safe, effective, and precise administration of gene-editing components. Focusing on successful preclinical and clinical applications, this paper explores current developments in combining gene editing with delivery strategies, with particular relevance to rare diseases, immuno-oncology, and monogenic disorder therapies. Additionally, it discusses challenges related to immunogenicity, scalability, off-target effects, and ethical considerations. By examining the current state and future prospects of this interdisciplinary approach, the study highlights its revolutionary impact on precision medicine. The integration of gene editing and targeted drug delivery technologies holds the potential to usher in a new era of personalized healthcare, enhancing therapeutic precision and enabling innovative treatments for unmet medical needs.

The pharmaceutical business is transitioning to a more sustainable model, with a greater emphasis on next-generation and green excipients to improve medicine formulation while reducing environmental impact. However, incorporating these innovative excipients into pharmaceutical development presents regulatory uncertainty, safety concerns, and compliance issues. This analysis delves into the growing regulatory framework governing next-generation excipients, emphasizing the difficulties of toxicological examination, approval routes, and worldwide regulatory agency harmonization initiatives. The article discusses the scientific advances that are driving the development of green excipients, including biodegradable polymers, plant-derived stabilizers, and biocompatible nanocarriers, as well as their safety profiles, biopharmaceutical performance, and scalability. It also examines regulatory challenges such as the lack of standardized evaluation frameworks, the necessity for in vitro and in silico risk assessment models, and the importance of Good Manufacturing Practices (GMP) and regulatory filings in assuring compliance. Furthermore, this study assesses the balance between innovation and regulation, arguing that the desire for environmentally friendly pharmaceutical excipients must be balanced with severe safety and effectiveness criteria. The possibility for regulatory change, collaborative industry efforts, and AI-driven predictive toxicity is also investigated as a significant facilitator for speeding up next-generation excipient approval. As the pharmaceutical industry adopts green chemistry concepts, bridging the gap between innovation and regulatory compliance will be critical for long-term medication development. This paper discusses how to overcome present hurdles and establish a proactive regulatory environment that promotes the safe and efficient use of next-generation excipients.