Smart Trypsin Adsorption into N-(2-Aminoethyl)-3-aminopropyl-Modified Mesoporous Silica for Ultra Fast Protein Digestion

Engineered Mesoporous Silica-Based Nanoparticles: Characterization of Surface Properties

Mesoporous silica-based nanomaterials have emerged as multifunctional platforms with applications spanning catalysis, medicine, and nanotechnology. Since their synthesis in the early 1990s, these materials have attracted considerable interest due to their unique properties, including high surface area, tunable pore size, and customizable surface chemistry. This article explores the surface properties of a series of MSU-type mesoporous silica nanoparticles, elucidating the impact of different functionalization strategies on surface characteristics. Through an extensive characterization utilizing various techniques, such as FTIR, Z-potential, and nitrogen adsorption porosimetry, insights into the surface modifications of mesoporous silica nanoparticles are provided, contributing to a deeper understanding of their nanostructure and related interactions, and paving the way to possible unexpected actionability and potential applications.

Hybrid Polymer-Silica Nanostructured Materials for Environmental Remediation

Due to the ever-growing global population, it is necessary to develop highly effective processes that minimize the impact of human activities and consumption on the environment. The levels of organic and inorganic contaminants have rapidly increased in recent years, posing a threat to ecosystems. Removing these toxic pollutants from the environment is a challenging task that requires physical, chemical, and biological methods. An effective solution involves the use of novel engineered materials, such as silica-based nanostructured materials, which exhibit a high removal capacity for various pollutants. The starting materials are also thermally and mechanically stable, allowing for easy design and development at the nanoscale through versatile functionalization procedures, enabling their effective use in pollutant capture. However, improvements concerning mechanical properties or applicability for repeated cycles may be required to refine their structural features. This review focuses on hybrid/composite polymer-silica nanostructured materials. The state of the art in nanomaterial synthesis, different techniques of functionalization, and polymer grafting are described. Furthermore, it explores the application of polymer-modified nanostructured materials for the capture of heavy metals, dyes, hydrocarbons and petroleum derivatives, drugs, and other organic compounds. The paper concludes by offering recommendations for future research aimed at advancing the application of polymer-silica nanostructured materials in the efficiency of pollutant uptake.

Mesoporous silica-based hybrid materials for bone-specific drug delivery

A mesoporous silica-based drug delivery device potentially useful for bone-specific drug delivery has been designed, developed and characterized starting from MSU-type mesoporous silica. The proposed system consists of a mesoporous silica nanoparticles (MSN) based vehicle, presenting alendronate as a targeting functionality for bone tissue while ibuprofen is used as a model molecule for the drugs to be delivered. The particles are functionalized on the external surface using a propionitrile derivative that is successively hydrolyzed to a carboxylic group. Alendronate, one of the most used member of the diphosphonate drug class, is electrostatically bonded to the external carboxyl functionalities of mesoporous silica. The obtained material has been characterized by powder X-ray diffraction, N₂ adsorption-desorption porosimetry, UV-vis spectrophotometry, FT-IR spectrometry and MAS-NMR ¹³C and ²⁹Si. Hydroxyapatite, which simulates the bone matrix, has been synthesized with the aim of testing the targeting activity of the obtained device. In a separate test, the MSNs have been loaded with ibuprofen, a non-steroidal anti-inflammatory drug (NSAID), and its release has been determined under neutral conditions by HPLC. Moreover, biological tests were carried out. The tested devices did not show any toxicity towards normal cells, confirming their high biocompatibility and the lack of off-target effects.

Hexagonal Mesoporous Silica as a Rapid, Efficient and Versatile Tool for MALDI-TOF MS Sample Preparation in Clinical Peptidomics Analysis: A Pilot Study

Improvement in high-throughput MALDI-TOF MS analysis requires practical and efficient sample preparation protocols for high acquisition rates. The use of hexagonal mesoporous silica (HMS) sorbents in combination with MALDI-TOF MS was explored as a versatile tool for peptidomic profiling of clinical specimens difficult to process, but considered important sources of disease biomarkers: synovial fluid and sputum. A rapid and efficient procedure, based on dispersive solid-phase extraction of peptides using commercially available wormhole mesostructured HMS, was tested for: a) pre-concentration of standard peptides in serially diluted solution up to the sub-nanomolar range; b) peptidome profiling of sputum and synovial fluid. The use of HMS, as dispersed sponges, significantly amplified the peptidic repertoire of sputum and synovial fluid by excluding from the adsorptive process large size proteins, which mask and/or suppress peptidome signals. The protocol proposed, as dispersive solid phase extraction, ensures good analytical performances. Moreover, it is economical and rapid, as it avoids the use of less reproducible and prolonged sample preparation procedures, such as the use of ultrafiltration filter devices. These findings may contribute to defining a high-throughput screening MS-based platform for monitoring key peptidic features of difficult to analyse bodily fluids in a clinical setting.

Recent advances in applications of nanomaterials for sample preparation

Sample preparation is a key step for qualitative and quantitative analysis of trace analytes in complicated matrix. Along with the rapid development of nanotechnology in material science, numerous nanomaterials have been developed with particularly useful applications in analytical chemistry. Benefitting from their high specific areas, increased surface activities, and unprecedented physical/chemical properties, the potentials of nanomaterials for rapid and efficient sample preparation have been exploited extensively. In this review, recent progress of novel nanomaterials applied in sample preparation has been summarized and discussed. Both nanoparticles and nanoporous materials are evaluated for their unusual performance in sample preparation. Various compositions and functionalizations extended the applications of nanomaterials in sample preparations, and distinct size and shape selectivity was generated from the diversified pore structures of nanoporous materials. Such great variety make nanomaterials a kind of versatile tools in sample preparation for almost all categories of analytes.

Novel trypsin-FITC@MOF bioreactor efficiently catalyzes protein digestion

A simple nanoporous metal organic framework (MOF) bioreactor preparation via a low energy 30 minute vortex as driving force to immobilize trypsin enzyme is presented. No chemical modifications were employed thus organic wastes were eliminated. The digestion efficiency of this trypsin bioreactor is exceptionally high, even when reused. This "green" synthesis procedure produced a "green" bioreactor.

The proteomics big challenge for biomarkers and new drug-targets discovery

In the modern process of drug discovery, clinical, functional and chemical proteomics can converge and integrate synergies. Functional proteomics explores and elucidates the components of pathways and their interactions which, when deregulated, lead to a disease condition. This knowledge allows the design of strategies to target multiple pathways with combinations of pathway-specific drugs, which might increase chances of success and reduce the occurrence of drug resistance. Chemical proteomics, by analyzing the drug interactome, strongly contributes to accelerate the process of new druggable targets discovery. In the research area of clinical proteomics, proteome and peptidome mass spectrometry-profiling of human bodily fluid (plasma, serum, urine and so on), as well as of tissue and of cells, represents a promising tool for novel biomarker and eventually new druggable targets discovery. In the present review we provide a survey of current strategies of functional, chemical and clinical proteomics. Major issues will be presented for proteomic technologies used for the discovery of biomarkers for early disease diagnosis and identification of new drug targets.

Simultaneous extraction and rapid visualization of peptidomic and lipidomic body fluids fingerprints using mesoporous aluminosilicate and MALDI-TOF MS

Herein we report the use of mesoporous aluminosilicate (MPAS) for the simultaneous extraction of peptides and lipids from complex body fluids such as human plasma and synovial fluid. We show that MPAS particles, given their mesostructural features with nanometric pore size and high surface area, are an efficient device for simultaneous extraction of peptidome and lipidome from as little as a few microliters of body fluids. The peptides and the lipids, selected and enriched by MPAS particles and rapidly visualized by MALDI-TOF MS, could form part of a diagnostic profile of the "peptidome" and the "lipidome" of healthy versus diseased subjects in comparative studies. The ability of this approach to rapidly reveal the overall pattern of changes in both lipidome and peptidome signatures of complex biofluids could be of valuable interest for handling large numbers of samples required in -omics studies for the purpose of finding novel biomarkers.

In mesopore protein digestion: a new forthcoming strategy in proteomics

The conventional protocols for in solution or in gel protein digestion require many steps and long reaction times. The use of trypsin immobilized onto solid supports has recently captured the attention of many research groups, because these systems can speed-up protein digestion significantly. The utilization of new materials such as mesoporous silica as supports, in which enzyme and substrate are dramatically concentrated and confined in the nanospace, offers new opportunities to reduce the complexity of proteomics workflows. An overview of the procedures for in situ proteolysis of single proteins or complex protein mixtures is reported, with a special focus on porous materials used as catalysts. The challenging efforts for designing such systems aimed at mimicking the biochemistry of living cells are reviewed. Potentials, limitations and challenges of this branch of enzyme catalysis, which we indicate as in mesopore digestion, are discussed, in relation to its suitability for high-speed and high-throughput proteomics.

Accurate determination of succinimide degradation products using high fidelity trypsin digestion peptide map analysis

We report an efficient, high fidelity trypsin digestion method for peptide map analysis. This method minimizes artifacts caused by the sample preparation process, and we show its utility for the accurate determination of succinimide formation in a degraded monoclonal antibody product. A basic charge variant was detected by imaged capillary isoelectric focusing and was shown with reduced antigen binding and biological activity. Samples were reduced under denaturing conditions at pH 5.0, and digestion of the reduced protein with porcine trypsin was performed at pH 7.0 for 1 h. Following reversed phase high-performance liquid chromatography and online mass spectrometric analysis, succinimide formation was identified at Asp30 in the light chain. This result contrasts with the observation of only iso-Asp and Asp residues under conventional sample preparation conditions, which are therefore concluded to be artificially generated. The Asp30 residue is seen in the cocrystal structure model to participate in favorable charge interaction with an antigen molecule. Formation of succinimide and the resulting loss of negative charge are therefore hypothesized to be the degradation mechanism. After treatment of the degraded antibody sample to mildly alkaline pH conditions, we observed only Asp residue as the succinimide hydrolysis product and concurrent recovery of biological activity.