Despite their advantageous morphological attributes and attractive physicochemical properties, mesoporous silica nanoparticles (MSNs) are merely supported as carriers or vectors for a reason. Incorporating various metal species in the confined nanospaces of MSNs (M-MSNs) significantly enriches their mesoporous architecture and diverse functionalities, bringing exciting potentials to this burgeoning field of research. These incorporated guest species offer enormous benefits to the MSN hosts concerning the reduction of their eventual size and the enhancement of their performance and stability, among other benefits. Substantially, the guest species act through contributing to reduced aggregation, augmented durability, ease of long-term storage, and reduced toxicity, attributes that are of particular interest in diverse fields of biomedicine. In this review, the first aim is to discuss the current advancements and latest breakthroughs in the fabrication of M-MSNs, emphasizing the pros and cons, the confinement of various metal species in the nanospaces of MSNs, and various factors influencing the encapsulation of metal species in MSNs. Further, an emphasis on potential applications of M-MSNs in various fields, including in adsorption, catalysis, photoluminescence, and biomedicine, among others, along with a set of examples is provided. Finally, the advances in M-MSNs with perspectives are summarized.(2-5 nm), tunable sizes (50-150 nm), shapes (hexagonal, wormhole-like, cubic, and lamellar) and morphologies (spheres, helical fibers, tubules, gyroids, crystals, and numerous other hierarchical complex architectures), ease of surface functionalization (both interior as well as exterior), unique topology, colloidal and thermal stabilities, and high dispersity. [4] The exceptional topology of surfactant-templated MSNs makes them unique with desirable properties that can be obtained by controlling the preparation conditions, such as the reaction temperature, pH value, stirring speed, and type of silica source, as well as surfactant, among others. [4j,m,n,5] These advantages make the MSNs as versatile materials and ideal choice for catalysis, [6] adsorption, [7] optical devices, [4j] polymeric fillers, [8] and diverse biomedical applications including bio-imaging, [4r,t,u,9] biocatalysts, [10] biosensing, [11] tissue engineering, [4f ] and drug/ gene delivery accounting for targeted and controlled release systems. [3d,4i,o-t,v,12] With these significant advantages and attractive physicochemical properties, it is highly anticipated to harness the desirable and beneficial properties of MSNs through the incorporation of various metals and their respective conjugates for exploration in innovative applications with exceptional performance. [13] The encapsulated metal species in the confined nanospaces of MSNs (M-MSNs) not only significantly enrich the mesoporous architecture and functionalities of MSN, but also tend to overcome their intrinsic limitations, such as their poor suspension ability and stability, lack of intrig...

In this study, a methodology utilizing peptide conformational imprints (PCIs) as a tool to specifically immobilize porcine pancreatic alpha-trypsin (PPT) at a targeted position is demonstrated. Owing to the fabrication of segment-mediated PCIs on the magnetic particles (PCIMPs), elegant cavities complementary to the PPT structure are constructed. Based on the sequence on targeted PPT, the individual region of the enzyme is trapped with different template-derived PCIMPs to show certain types of inhibition. Upon hydrolysis, N-benzoyl-L-arginine ethyl ester (BAEE) is employed to assess the hydrolytic activity of PCIMPs bound to the trypsin using high-performance liquid chromatography (HPLC) analysis. Further, the kinetic data of four different PCIMPs are compared. As a result, the PCIMPs presented non-competitive inhibition toward trypsin, according to the Lineweaver-Burk plot. Further, the kinetic analysis confirmed that the best parameters of PPT/PCIMPs 233–245+G were Vmax = 1.47 × 10−3 mM s−1, Km = 0.42 mM, kcat = 1.16 s−1, and kcat/Km = 2.79 mM−1 s−1. As PPT is bound tightly to the correct position, its catalytic activities could be sustained. Additionally, our findings stated that the immobilized PPT could maintain stable activity even after four successive cycles.

Alzheimer’s disease (AD), an age-related neurodegenerative disease, the most common causes of dementia is a multifactorial pathology categorized by a complex etiology. Numerous nutraceuticals have been clinically evaluated, but some of the trials failed. However, natural compounds have some limitations due to their poor bioavailability, ineffective capability to cross the blood–brain barrier, or less therapeutic effects on AD. To overcome these disadvantages, nanoparticle-conjugated natural products could promote the bioavailability and enhance the therapeutic efficacy of AD when compared with a naked drug. This application generates and implements new prospect for drug discovery in neurodegenerative diseases. In this article, we confer AD pathology, review natural products in clinical trials, and ascertain the importance of nanomedicine coupled with natural compounds for AD.

Peptide conformational imprints (PCIs) offer a promising perspective to directly generate binding sites for preserving enzymes with high catalytic activity and stability. In this study, we synthesized a new chiral cross-linker cost-effectively for controlling the matrix morphology of PCIs on magnetic particles (PCIMPs) to stabilize their recognition capability. Meanwhile, based on the flank part of the sequences on papain (PAP), three epitope peptides were selected and synthesized. Molecularly imprinted polymers (MIPs) were then fabricated in the presence of the epitope peptide using our new cross-linker on magnetic particles (MPs) to generate PCIMPs. PCIMPs were formed with helical cavities that complement the PAP structure to adsorb specifically at the targeted position of PAP. PCIMPs65–79 were found to have the best binding parameters to the PAP with Kd = 0.087 μM and Bmax = 4.56 μM. Upon esterification of N-Boc-His-OH, proton nuclear magnetic resonance (1H-NMR) was used to monitor the yield of the reaction and evaluate the activity of PAP/PCIMPs. The kinetic parameters of PAP/PCIMPs65–79 were calculated as Vmax = 3.0 μM s−1, Km = 5 × 10−2 M, kcat = 1.1 × 10–1 s−1, and kcat/Km = 2.2 M−1 s−1. In addition, PAP is bound tightly to PCIMPs to sustain its activity after four consecutive cycles.