This paper reports recent advancements in chitosan‐based antimicrobial biomaterials that aim to address the issue of antimicrobial resistance (AMR). Today, AMR is one of the most significant public health challenges the world is facing. To combat the overuse of antibiotics, a range of materials, including advanced nanosized polymers, have been explored as potential antimicrobial agents. In this direction, chitosan scores highly because of its unique combination of properties such as biodegradability, biocompatibility, bioactivity, non‐toxic, and, most importantly, its intrinsic antibacterial and antifungal activity. Herein, an overview of chitosan and its derivatives as potential alternatives to conventional antimicrobial therapeutics is reported. This review starts with understanding the AMR mechanism, which is critical for developing suitable materials for treating infectious diseases. Then, the inherent characteristics, modes of antimicrobial action, and factors that impact the antimicrobial effectiveness of chitosan and its derivatives are discussed. The authors further summarize various clinical trial results of chitosan‐based materials as antimicrobial agents. Finally, various antimicrobial applications of chitosan‐based materials are reported. In summary, this review offers new insights into the design of chitosan‐based sustainable materials for various antimicrobial applications.

According to the World Health Organization (WHO), there are more than 2.3 million cases of breast cancer (BC) each year, with 80% of deaths occurring in low‐ and middle‐income countries (LMICs). Chemotherapeutic agents are used in the treatment of BC to kill or slow the growth of cancer cells. While they can be effective in many cases, they also have potential side effects. These include long‐term effects such as possible damage to healthy organs, limited efficacy, and resistance development. Trastuzumab (Tmab) offers superior treatment options due to low toxicity and high specificity for a target antigen. However, Tmab treatment, despite being available for the last two decades, has remained challenging and expensive to manage, and inaccessible to people in underserved communities. Therefore, it is necessary to ensure that such effective medication is within reach of those in need, regardless of social or economic class. Recent advances in nanomedicine have led to a growing number of studies that show promise in meeting these challenges through access to adequate anticancer drugs in LMICs. This review analyzes such reports while highlighting the progress of nanomedicine and anticancer drug systems and presents opportunities that have been overlooked over the years for LMICs.

N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (HTCC), a quaternized chitosan derivative, has been shown to exhibit a broad spectrum of antimicrobial activity, especially against bacteria and enveloped viruses. Despite this, molecular docking studies showing its atomic-level mechanisms against these microorganisms are scarce. Here, for the first time, we employed molecular docking analyses to investigate the potential antibacterial activity of HTCC against Staphylococcus aureus and its antiviral activity against human immunodeficiency virus 1 (HIV-1). According to the findings, HTCC exhibited promising antibacterial activity with high binding affinities; however, it had limited antiviral activity. To validate these theoretical outcomes, experimental studies were conducted. Different derivatives of HTCC were synthesized and characterized using NMR, XRD, FTIR, and DLS. The in vitro assays validated the potent antibacterial efficacy of HTCC against S. aureus, whereas the antiviral studies did not show good antiviral activity. However, our research also revealed a promising avenue for further exploration of the antimicrobial activity of HTCC nanoparticles (NPs), since, thus far, no studies have been conducted to show the antiviral activity of HTCC NPs against HIV-1. The nanosized HTCC exhibited superior antiviral performance compared to the parent polymers, with complete (100%) inhibition of HIV-1 viral activity at the highest tested concentration (0.33 mg/mL).

Betulinic acid (BA) is a promising natural anti‐tumor agent renowned for its activity against various tumor cell types. Despite its favorable profile of low cytotoxicity to normal cells, BA's inherent hydrophobic nature and relatively short systematic half‐life impose hurdles for clinical application. This study introduces a strategy to surmount these obstacles by developing a drug delivery system employing poly(lactic‐co‐glycolic acid) (PLGA)‐encapsulated BA nanoparticles (PLGA‐BA NPs). Rigorous characterization techniques such as dynamic light scattering (DLS), x‐ray diffraction (XRD), and scanning electron microscopy (SEM) analyses are employed to confirm the integrity of the drug within the nanocarriers. The PLGA‐BA NPs demonstrated a mean particle size of 196 ± 6.80 nm. XRD analysis demonstrated the amorphous state of the PLGA‐BA formulation, a characteristic vital for sustained drug release and enhanced bioavailability. The PLGA‐BA NPs exhibited spherical morphology with encapsulation and loading efficiency of 83 ± 9.24% and 7.0 ± 0.4%, respectively, highlighting efficient encapsulation of the drug within the PLGA NPs. In vitro, cytotoxicity assessments demonstrated enhanced anti‐proliferative efficacy against breast and lung tumor cells when utilizing PLGA‐BA NPs in comparison to free BA. This research underlines the potential of employing the developed PLGA‐based nanocarrier to optimize the therapeutic efficacy of BA.

Uncomplicated malaria is effectively treated with oral artemisinin‐based combination therapy (ACT). Yet, there is an unmet clinical need for the intravenous treatment of the more fatal severe malaria. There is no combination intravenous therapy for uncomplicated due to the nonavailability of a water‐soluble partner drug for the artemisinin, artesunate. The currently available treatment is a two‐part regimen split into an intravenous artesunate followed by the conventional oral ACT . In a novel application of polymer therapeutics, the aqueous insoluble antimalarial lumefantrine is conjugated to a carrier polymer to create a new water‐soluble chemical entity suitable for intravenous administration in a clinically relevant formulation . The conjugate is characterized by spectroscopic and analytical techniques, and the aqueous solubility of lumefantrine is determined to have increased by three orders of magnitude. Pharmacokinetic studies in mice indicate that there is a significant plasma release of lumefantrine and production its metabolite desbutyl‐lumefantrine (area under the curve of metabolite is ≈10% that of the parent). In a Plasmodium falciparum malaria mouse model, parasitemia clearance is 50% higher than that of reference unconjugated lumefantrine. The polymer‐lumefantrine shows potential for entering the clinic to meet the need for a one‐course combination treatment for severe malaria.

Malnutrition and poor diet constitute the number one driver of the global burden of disease. Undernutrition is responsible for up to 50% of all deaths in children under the age of 5. In South Africa, 25% of the country’s children suffer from undernutrition. This increases the risk of child mortality as well as contracting infectious diseases. It also affects the physical and intellectual development of the children. The greatest drawback in malnutrition is the deficiency of essential nutraceuticals involved in important biological functions. Innovative technologies such as nanoformulated products are needed for food and agriculture in order to enhance the children’s health. The evaluation and application of various nanoformulated delivery systems will be explored for improving the stability and bioavailability of essential nutraceuticals for consumers.