Natural and renewable sources of calcium carbonate (CaCO₃), also referred to as “biogenic” sources, are being increasingly investigated, as they are generated from a number of waste sources, in particular those from the food industry. The first and obvious application of biogenic calcium carbonate is in the production of cement, where CaCO₃ represents the raw material for clinker. Overtime, other more added-value applications have been developed in the filling and modification of the properties of polymer composites, or in the development of biomaterials, where it is possible to transform calcium carbonate into calcium phosphate for the substitution of natural hydroxyapatite. In the majority of cases, the biological structure that is used for obtaining calcium carbonate is reduced to a powder, in which instance the granulometry distribution and the shape of the fragments represent a factor capable of influencing the effect of addition. As a result of this consideration, a number of studies also reflect on the specific characteristics of the different sources of the calcium carbonate obtained, while also referring to the species-dependent biological self-assembly process, which can be defined as a more “biomimetic” approach. In particular, a number of case studies are investigated in more depth, more specifically those involving snail shells, clam shells, mussel shells, oyster shells, eggshells, and cuttlefish bones.

Neuropathic pain is a significant global clinical issue that poses substantial challenges to both public health and the economy due to its complex underlying mechanisms. It has emerged as a serious health concern worldwide. Recent studies involving dorsal root ganglion (DRG) stimulation have provided strong evidence supporting its effectiveness in alleviating chronic pain and its potential for sustaining long-term pain relief. In addition to that, there has been ongoing research with clinical evidence relating to the role of small non-coding ribonucleic acids known as microRNAs in regulating gene expressions affecting pain signals. The signal pathway involves alterations in neuronal excitation, synaptic transmission, dysregulated signaling, and subsequent pro-inflammatory response activation and pain development. When microRNAs are dysregulated in the dorsal root ganglia neurons, they polarize macrophages from anti-inflammatory M2 to inflammatory M1 macrophages causing pain signal generation. By reversing this polarization, a therapeutic activity can be induced. However, the direct delivery of these nucleotides has been challenging due to limitations such as rapid clearance, degradation, and reduction in half-life. Therefore, safe and efficient carrier vehicles are fundamental for microRNA delivery. Here, we present a comprehensive analysis of miRNA-based nano-systems for chronic neuropathic pain, focusing on their impact in dorsal root ganglia. This review provides a critical evaluation of various delivery platforms, including viral, polymeric, lipid-based, and inorganic nanocarriers, emphasizing their therapeutic potential as well as their limitations in the treatment of chronic neuropathic pain. Innovative strategies such as hybrid nanocarriers and stimulus-responsive systems are also proposed to enhance the prospects for clinical translation. Serving as a roadmap for future research, this review aims to guide the development and optimization of miRNA-based therapies for effective and sustained neuropathic pain management.

Antimicrobial drug resistance is increasing at an alarming rate and has resulted in causing threat to the public health sector. Due to inefficiency of drugs and as a result of the advent of new resistance mechanisms, the microbial agents have developed multidrug resistance, thereby enhancing the morbidity and mortality rates, and earning the title “super bugs.” In addition to this improper sanitary facilities and inappropriate dietary habits have further peaked the multidrug resistance (MDR) spread. MDR has affected human health in ways beyond human comprehension such as prolonged illness, immense risk of death as well as high expenditures in hospital and medical bills. This ever-increasing crisis has led to new avenues such as antimicrobial polymers that possesses zero toxicity to cells. Inherent antimicrobial capacity along with various antimicrobial modes, biocompatibility, stability, structure, functionalities, low cost synthesis, and eco-friendly nature are few among the most promising features of the antimicrobial polymers. Quaternary ammonium salts (QAS) and quaternary phosphonium salts (QPS) are the most common types of antimicrobial polymers, but in-order to effectively combat the microbes there was a need of membrane active cationic polymers. Thus emerged “Polyionenes.” The additional dimension and the commercial 92availability of numerous building blocks are the key features that render the MDR pathogens ineffective. Polyionenes along with its key features ease of synthesis and scale-up have thus made its place in being the one of the most important family in anti-microbial polymers.