Syed Muhammad Ahmad

6-Mercaptopurine (6-MP) is a potent chemotherapeutic and immunosuppressive agent; however, its oral administration is limited by poor bioavailability and dose-dependent hepatotoxicity. This study aimed to develop and optimize a colon-targeted, pH-responsive delivery system for 6-MP using Eudragit S100-coated thiolated chitosan/casein microbeads (Eu-S100@TCh/CS) to enhance site-specific release and minimize systemic exposure. The microbeads were fabricated via emulsion cross-linking followed by solvent evaporation and optimized using a central composite design. Physicochemical characterization (FTIR spectroscopy, DSC/TGA, PXRD, and SEM) confirmed efficient drug incorporation in a molecularly dispersed state, thermal stability, and a uniform spherical morphology (541-672 µm). Swelling and dissolution studies demonstrated a clear pH-dependent behavior, with minimal swelling and negligible drug release at pH 1.2 and 6.8, and enhanced release (84.5% at 24 h) at colonic pH 7.4, corresponding to the dissolution of the Eudragit S100 coating and hydration of the polymeric core. Drug-release kinetics indicated Higuchi diffusion for uncoated beads (R ² = 0.9852; n = 0.624) and anomalous (non-Fickian) transport for the coated beads (R ² = 0.9994; n = 0.741), governed by combined diffusion and polymer relaxation mechanisms. Acute oral toxicity studies in rats revealed no significant alterations in the biochemical, hematological, or histopathological parameters, confirming systemic safety. In vitro cytotoxicity studies (MTT assay) showed enhanced antiproliferative activity of the 6-MP-loaded microbeads against HCT-116 cells compared to the free drug, attributed to improved solubility and sustained drug availability following release rather than whole-particle internalization. Blank microbeads exhibited high cell viability, confirming carrier biocompatibility. Overall, the Eu-S100@TCh/CS microbead system represents a rationally designed colon-targeted delivery platform with potential to improve local therapeutic efficacy and reduce systemic toxicity. Further studies are warranted to evaluate selectivity using normal colonic cell lines.

A unique method for creating drug-related nanofibers (NFs) involves electrospinning. According to reported procedures, therapies utilizing hazardous solvents or synthetic chemicals have not been authorized by the most recent drug regulations. This chapter has concentrated on studies that meet the criteria for non-toxic substances. In order to provide ideal circumstances for generating NF, electrospinning, its benefits, solutions, and process conditions, followed by characterization, will focus on safety and a regulatory emphasis. The current state of characterization of NFs is being reviewed, especially regarding chemicals entrapped within them. This makes the electrospinning application of drug-loaded NFs composition-dependent; so far, much research has been carried out using toxic solvents and FDA-unapproved crosslinking systems. The parameters of processing provide a way for the technology to be potentially accepted in the pharmaceutical industry. It has been concluded that suggestions concerning reproducibility, repeatability, and erroneous conclusions arise from the poor understanding of NF characterization techniques. Static NF release models were created that can provide safety evidence. However, some dynamic models for release can give better limitations regarding nontoxic nanostructured matrices. Many countries have developed, or at least are in the process of developing, standards. Finally, issues related to new biopolymers, their applications, and trends that can facilitate the commercialization of drug-related NFs were addressed.

Tissue engineering has developed as an innovative method for enhancing treatment results by ameliorating tissue abnormalities and degenerations that can significantly hinder organ function. The three primary components of tissue engineering are scaffolds, cells, and biomolecules. Electrospinning is an efficient and novel method for fabricating cell scaffolds made of sub-microscale and nanoscale fibers that closely mimic the natural extracellular matrix. However, the dense packing of fibers in electrospun scaffolds, which results in small pore sizes, raises concerns about their ability to facilitate tissue ingrowth and cell infiltration. To overcome this issue, researchers have devised and examined many techniques to modify scaffold design and increase pore size. These methodologies include physical processes such as gas foaming, salt leaching, and the use of custom-designed collectors to create electrospun scaffolds with looser fiber structures and larger pores. This chapter provides an overview of such advanced electrospinning techniques, which may inspire the development of novel methods for improving scaffold design and expanding their regenerative biomedical applications.

Electrospinning is a promising approach for synthesizing polymeric nanofibers with diverse applications in drug delivery systems. This chapter focuses on the design and characterization processes of electrospun-based nanoformulations, together with their complexities. Various electrospinning-based nanoformulations, including drug-loaded and core-shell structures, are explained in detail, emphasizing the design concept, type of polymer used, and fundamental mechanisms that control their functionality. Among these, nano-sized formulations include antimicrobial nanofibers designed to combat infections and biodegradable nanofibers that support tissue engineering and controlled release of medication. Fabrication methods like blend, coaxial, and melt techniques are mainly discussed along with the necessary modifications related to polymeric solvents and electrospinning equipment to achieve optimal nanofibers with certain qualities in this chapter. Furthermore, critical aspects affecting the effectiveness of electrospun-produced nanofibers and the accurate characterization methods including morphological study, structural elucidation, drug release profile for assessment are discussed. Over all, this chapter reveals the possibilities linked to electrospinning for both nanotechnology and medicine combinedly.

Corroles, a class of tetrapyrrolic macrocycles, have garnered significant attention for their potential in cancer therapy due to their unique structural chemistry and ability to coordinate with metals. Their remarkable photophysical properties make them beneficial for photodynamic therapy (PDT) and fluorescence imaging, as they can produce reactive oxygen species when activated by light, offering potential for the treatment of various carcinomas, including hepatic, breast, pancreatic, and lung cancers. Despite the encouraging preclinical and clinical data supporting their therapeutic efficacy, challenges remain in optimizing corrole formulations, particularly concerning targeted delivery, stability, and bioavailability. This review highlights current advancements in corrole-based therapies, focusing on novel nanoparticle formulations that enhance drug distribution and therapeutic efficacy. Furthermore, it examines the mechanisms of corrole-mediated cellular death and the role of photodynamic treatment in inducing apoptosis via various signaling pathways. Additional research is necessary to address formulation-related issues while ensuring the safety and effectiveness of corroles in cancer treatment, therefore maximizing their therapeutic potential and adhering to regulatory standards.