Molecular Recognition Ability Research Articles

DNA Nanomaterial-Based Electrochemical Biosensors for Clinical Diagnosis.

Sensitive and quantitative detection of chemical and biological molecules for screening, diagnosis and monitoring diseases is essential to treatment planning and response monitoring. Electrochemical biosensors are fast, sensitive, and easy to miniaturize, which has led to rapid development in clinical diagnosis. Benefiting from their excellent molecular recognition ability and high programmability, DNA nanomaterials could overcome the Debye length of electrochemical biosensors by simple molecular design and are well suited as recognition elements for electrochemical biosensors. Therefore, to enhance the sensitivity and specificity of electrochemical biosensors, significant progress has been made in recent years by optimizing the DNA nanomaterials design. Here, the establishment of electrochemical sensing strategies based on DNA nanomaterials is reviewed in detail. First, the structural design of DNA nanomaterial is examined to enhance the sensitivity of electrochemical biosensors by improving recognition and overcoming Debye length. In addition, the strategies of electrical signal transduction and signal amplification based on DNA nanomaterials are reviewed, and the applications of DNA nanomaterial-based electrochemical biosensors and integrated devices in clinical diagnosis are further summarized. Finally, the main opportunities and challenges of DNA nanomaterial-based electrochemical biosensors in detecting disease biomarkers are presented in an aim to guide the design of DNA nanomaterial-based electrochemical devices with high sensitivity and specificity.

Intensifying the CO2/N2 separation performance of PVAm membrane by amine-functionalized porous montmorillonite

Multilayered montmorillonite (MMT) exhibits the building block stacking in polymer matrix, which has tortuous transport passageways and a few CO2 affinity sites, thus mixed matrix membranes incorporated with MMT have low molecular recognition ability for CO2. Herein, the porous MMT (p-MMT) was initially prepared through the solid-phase desilication reaction, and then amine-functionalized p-MMT (P3.2@p-MMT) was synthesized by the electrostatic interaction between positively charged polyethyleneimine (PEI) and negatively charged p-MMT, in which PEI was confined within the pore. Subsequently, mixed matrix composite membranes (MMCMs) were developed by the dispersion of polyvinylamine (PVAm) and P3.2@p-MMT, as well as hydrophilic-modified polysulfone as a support. It was observed that P3.2@p-MMT was uniformly dispersed in polymer matrix, and two phases had good interfacial compatibility due to hydrogen bonding. As a result, the gas separation performance of as-prepared MMCMs achieved a CO2 permeance of 217 GPU with a CO2/N2 selectivity of 112.3, which were 2.97 and 2.45 times that of the pristine PVAm membrane, and 1.57 and 2.49 times that of MMCMs incorporated with p-MMT respectively. The excellent gas separation performance is attributed to the relatively straight transport passageways, which originates from P3.2@p-MMT. Moreover, the amine groups within the pore of P3.2@p-MMT facilitate CO2 transport in the MMCMs. In addition, as-prepared MMCMs had high stability during over 360 h-testing, which displayed an average CO2 permeance of 238 GPU with the CO2/N2 selectivity of 124.1 utilizing a gas mixture as the feed gas.

Preparation of two amphiphilic dendritic small molecule gelators based on poly (aryl ether) modified silica-based chromatographic stationary phases and molecular shape recognition for shape-restricted isomers

Geometric isomers tend to have similar polarities and differ only in molecular shape. Vigorously developing new stationary phases to meet the requirements for the separation of isomers that have similar physicochemical properties is still an urgent topic in separation science. Poly (arylene ether)-based dendrimers are known for their multifunctional branched peripheral structures and high self-assembly properties. In this paper, two amphiphilic dendritic organic small molecule gelling agents based on poly (aryl ether), PAE-ANT and PAE-PA, were prepared and conjugated to the silica surface. SiO2@PAE-ANT and SiO2@PAE-PA were used as HPLC stationary phases for the separation of non-polar shape-restricted isomers. Both stationary phases have very high molecular shape selectivity for isomers such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), tocopherols and carotenoids. Separation of cis-trans geometric isomers such as diethylstilbestrol and polar compounds such as monosubstituted benzenes and anilines can also be achieved. These two columns offer more flexible selectivity and higher separation performance than commercial C18 and phenyl columns. There is a difference in molecular shape selectivity between the two stationary phases for the same analyte test probes. SiO2@PAE-ANT showed slightly better linear selectivity for non-polar shape-restricted isomers compared to SiO2@PAE-PA with Janus-type PAE-PA bonding phase. This separation behavior may be attributed to the ordered spatial structure formed by the gel factor on the surface of the stationary phase and the combined effect of multiple weak interaction centers (hydrophobic, hydrophilic, hydrogen bonding and π-π interactions). It was also possible to separate nucleoside and nucleobase strongly polar compounds well in the HILIC mode, suggesting that hydrophilic groups in PAE-ANT and PAE-PA are involved in the interactions, reflecting their amphiphilic nature.The results show that the ordered gelation of dendritic organic small molecule gelators on the SiO2 surface, along with multiple carbonyl-π, π-π and other interactions, play a crucial role in the separating shape-restricted isomers. The integrated and ordered functional groups serve as the primary driving force behind the exceptionally high molecular shape selectivity of SiO2@PAE-ANT and SiO2@PAE-PA phases. Alterations in the structure of dendritic organic small molecule gelators can impact both molecular orientation and recognition ability, while changes in the type of functional groups influences the separation mechanism of shape-restricted isomers.

The series of L-lysine-derived gelators-modified multifunctional chromatography stationary phase for separation of chiral and achiral compounds

In this study, using chiral L-lysine as the molecular skeleton, three kinds of L-lysine-derived gelators (GBLB, GBLF and GFLF) were synthesized and then bonded to the surface of silica matrix (5 μm) by amide condensation to prepare a series of multifunctional chromatography stationary phases (GBLB-SiO2, GBLF-SiO2, and GFLF-SiO2) were prepared. The L-lysine-derived gelators not only possess chiral recognition ability, but also can spontaneously form oriented and ordered network structures in liquid medium through the interaction of non-covalent bonding forces such as hydrogen bonding, π-π stacking, and van der Waals forces. The comprehensive effect of multiple weak interaction sites enhances the molecular recognition ability and further improves the separation diversity of different types of compounds on stationary phases. The separation and evaluation of chiral compounds showed that benzoin, 1-phenyl-ethanol, 1-phenyl-propanol and 6-hydroxyflavanone could be separated in normal phase mode (NPLC). The separation of different types of non-chiral compounds, such as sulfonamides, nucleosides, nucleobases, polycyclic aromatic hydrocarbons (PAHs), anilines, and aromatic acids, were achieved in hydrophilic interaction/reversed-phase/ion-exchange mode (HILIC/RPLC/IEC), and the separation of polarized compounds could be performed under the condition of ultrapure water as the mobile phase, which has the typical retention characteristics of per aqueous liquid chromatography (PALC). The effects of organic solvent content, temperature, pH value, and buffer salt concentration on the retention and separation performance of the column were investigated. Comparison of the three prepared columns showed that the separation performance (such as aromatic selectivity) could be improved by increasing the types of functional groups on the surface of the stationary phase and the number of aromatic groups. In a word, the prepared stationary phase have multiple retention properties, can simultaneously separate chiral compounds and various types of achiral compounds. This work provides an idea for developing multifunctional liquid chromatography stationary phase materials, and further expands the application of gelators in separation science.

Synthesis, Characterization and Application of New Polymers Imprinted with Zinc (II) Ions

In this work, molecularly imprinted polymers with zinc imprints and their comparison polymers without imprints were synthesized. A comparative characterization of the physical parameters of the synthesized zinc-imprinted (ZnIP) and non-imprinted (NIP) polymers was carried out using the methods of elemental analysis, conductometry, scanning electron microscopy, and IR-Fourier spectroscopy. The ability of the resulting polymers to molecularly recognize zinc was evaluated. Based on experimental data on static adsorption, the adsorption capacity of ZnIP and NIP was determined using an atomic emission spectrometer. It was found that ZnIP is characterized by better physical parameters and a higher ability for molecular recognition of zinc compared to NIP. ZnIP with zinc imprints were found to have better sorption capacity for zinc than their reference polymers. The sorption of zinc by molecular imprinted ZnIP is mainly due to the complex formation and pores of the initial carbon product. The synthesized ZnIP have increased porosity. The presence of pores with a diameter <50 nm in ZnIP is associated with voids formed after acid hydrolysis, which is clearly visible in images recorded by scanning electron microscopy. Thus, the possibility of using ZnIP as a selective sorbent has been established.

Colorimetric Immunoassays with Boronic Acid-Decorated, Peroxidase-like Metal-Organic Frameworks as the Carriers of Antibodies and Enzymes.

The sensitivity of immunoassays is generally limited by the low signal reporter/recognition element ratio. Nanomaterials serving as the carriers can enhance the loading number of signal reporters, thus improving the detection sensitivity. However, the general immobilization strategies, including direct physical adsorption and covalent coupling, may cause the random orientation and conformational change in proteins, partially or completely suppressing the enzymatic activity and the molecular recognition ability. In this work, we proposed a strategy to load recognition elements of antibodies and enzyme labels using boronic acid-modified metal-organic frameworks (MOFs) as the nanocarriers for signal amplification. The conjugation strategy was proposed based on the boronate ester interactions between the carbohydrate moieties in antibodies and enzymes and the boronic acid moieties on MOFs. Both enzymes and MOFs could catalyze the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2, therefore achieving dual signal amplification. To indicate the feasibility and sensitivity of the strategy, colorimetric immunoassays of prostate specific antigen (PSA) were performed with boronic acid-modified Cu-MOFs as peroxidase mimics to catalyze TMB oxidation and nanocarriers to load antibody and enzyme (horseradish peroxidase, HRP). According to the change in the absorbance intensity of the oxidized TMB (oxTMB), PSA at the concentration range of 1~250 pg/mL could be readily determined. In addition, this work presented a site-specific and oriented conjugation strategy for the modification of nanolabels with recognition elements and signal reporters, which should be valuable for the design of novel biosensors with high sensitivity and selectivity.

"Three-in-One" Plasmonic Au@PtOs Nanocluster Driven Lateral Flow Assay for Multimodal Cancer Exosome Biosensing.

Exploiting the multiple properties of nanozymes for the multimode lateral flow assay (LFA) is urgently required to improve the accuracy and versatility. Herein, we developed a novel plasmonic Au nanostar@PtOs nanocluster (Au@PtOs) as a multimode signal tag for LFA detection. Based on the PtOs bimetallic nanocluster doping strategy, Au@PtOs can indicate both excellent SERS enhancement and nanozyme catalytic activity. Meanwhile, Au@PtOs displays a better photothermal effect than that of Au nanostars. Therefore, catalytic colorimetric/SERS/temperature three-mode signals can be read out based on the Au@PtOs nanocomposite. The Au@PtOs was combined with LFA and applied for breast cancer exosome detection. The detection limit for the colorimetric/SERS/temperature mode was 2.6 × 103/4.1 × 101/4.6 × 102 exosomes/μL, respectively, which was much superior to the common Au nanoparticles LFA (∼105 exosomes/μL). Moreover, based on the fingerprint molecular recognition ability of the SERS mode, exosome phenotypes derived from different breast cancer cell lines can be discriminated easily. Based on the convenient visual colorimetric mode and sensitive SERS/temperature quantitative modes, Au@PtOs driven LFA can satisfy the requirements of accurate and flexible multimodal sensing in different application scenarios.

Histamine-Responsive Hydrogel Biosensors Based on Aptamer Recognition and DNA-Driven Swelling Hydrogels.

Detection of chemical substances is essential for living a healthy and cultural life in the modern world. One type of chemical sensing technology, biosensing, uses biological components with molecular recognition abilities, enabling a broad spectrum of sensing targets. Short single-stranded nucleic acids called aptamers are one of the biological molecules used in biosensing, and sensing methods combining aptamers and hydrogels have been researched for simple sensing applications. In this research, we propose a hydrogel-based biosensor that uses aptamer recognition and DNA-driven swelling hydrogels for the rapid detection of histamine. Aptamer recognition and DNA-driven swelling hydrogels are directly linked via DNA molecular reactions, enabling rapid sensing. We selected histamine, a major food poisoning toxin, as our sensing target and detected the existence of histamine within 10 min with significance. Because this sensing foundation uses aptamers, which have a vast library of targets, we believe this system can be expanded to various targets, broadening the application of hydrogel-based biosensors.

The Integral Role of Conjugate Acids in Brønsted Base‐Catalyzed Regiodivergent Synthesis

Catalyst‐controlled diversity‐oriented synthesis (CatDOS) is an important research area for expanding molecular complexities and achieving high atomic economics. Plenty of regiodivergent syntheses have been achieved through metal catalysis, covalent and non‐covalent organocatalysis by controlling the molecular recognition function of the catalysts. However, the development of regiodivergent CatDOS through Brønsted base in organocatalysis was relatively less than others. Numerous studies about Brønsted base organocatalysis have demonstrated the powerful molecular recognition abilities of their cationic conjugate acids (CA) mainly in controlling the stereoselectivity instead of the regioselectivity. This concept review aims to conceptualize a new perspective to consider the potential role of the cationic CA of Brønsted bases for regiodivergent CatDOS. Recent representative examples are selected to demonstrate the potential of cationic CA on site‐selectivity control in single‐bond and multiple‐bond formation reactions. The summarized results show that even CA of common tertiary amines, protic ammonium ions, could affect the regioselectivity in the early‐ or late‐stage step during multiple‐bond formation after initial deprotonation. The results also hinted that the properties and ion‐pairing interactions of CA could be more important than the basicity of bases in controlling regioselectivity. Perspectives and hypotheses for explanation of the mechanism of regioselectivity are also included in this review.

Cytochrome c electrochemical detection utilizing molecularly imprinted poly(3, 4-ethylenedioxythiophene) on a disposable screen printed carbon electrode

Cytochrome c (cyt c) has been found to play a function in apoptosis in cell-free models. This work presents the creation of molecularly imprinted conducting poly(3, 4-ethylenedioxythiopene) (MIPEDOT) on the surface of a screen printed carbon electrode (SPCE) for cyt c. Cyt c was imprinted by electropolymerization due to the presence of an EDOT monomer hydrophobic functional group on SPCE, using CV to obtain highly selective materials with excellent molecular recognition ability. MIPEDOT was characterized by CV, EIS, and DPV using ferricyanide/ferrocyanide as a redox probe. Further, the characterization of the sensor was accomplished using SEM for surface morphological confirmation. Using CV, the peak current measured at the potential of +1 to −1 V (vs. Ag/AgCl) is linear in the cyt c concentration range from 1 to 1200 pM, showing a remarkably low detection limit of 0.5 pM (sensitivity:0.080 μA pM). Moreover, the applicability of the approach was successfully confirmed with the detection of cyt c in biological samples (human plasma). Similarly, our research has proven a low-cost, simple, and efficient sensing platform for cyt c detection, rendering it a viable tool for the future improvement of reliable and exact non-encroaching cell death detection.

DNA Reaction Circuits to Establish Designated Biological Functions in Multicellular Community.

In multicellular organisms, individual cells are coordinated through complex communication networks to accomplish various physiological tasks. Aiming to establish new biological functions in the multicellular community, we used DNA as the building block to develop a cascade of nongenetic reaction circuits to establish a dynamic cell-cell communication network. Utilizing membrane-anchored amphiphilic DNA tetrahedra (TDN) as the nanoscaffold, reaction circuits were incorporated into three unrelated cells in order to uniquely regulate their sense-and-response behaviors. As a proof-of-concept, this step enabled these cells to simulate significant biological events involved in T cell-mediated anticancer immunity. Such events included cancer-associated antigen recognition and the presentation of antigen-presenting cells (APCs), APC-facilitated T cell activation and dissociation, and T cell-mediated cancer targeting and killing. By combining the excellent programmability and molecular recognition ability of DNA, our cell-surface reaction circuits hold promise for mimicking and manipulating many biological processes.

Synthetic Modifications of a Pb2+-Sensor Acridono-Crown Ether for Covalent Attachment and Their Effects on Selectivity.

Because of environmental impact, there is a great need for chemosensors, especially for toxic heavy metals such as lead. The conventional instrumental analytical techniques rarely provide an available real-time sensing platform, thus the development of highly selective and stable synthetic chemosensor molecules is of great importance. Acridono-18-crown-6 ethers have such properties, and much research has proven their outstanding applicability in various supramolecular devices. In this present work, we aimed to enable their covalent immobilization capability by synthesizing functionalized derivatives while preserving the favored molecular recognition ability. Several new macrocycle analogues were synthesized, while synthetization difficulties and design aspects were also dealt with. The selectivity of the macrocycle analogues was studied using UV-Vis spectroscopy and compared with that of the parent compounds. The ultimate crown ether derivative showed high Pb2+-selectivity, reversibility (decomplexation by extraction with water) and stability.

Integrating liquid chromatography-electrochemical detection-surface Enhanced Raman Spectroscopy on microfluidic chip for phenylurea herbicides analysis

The widespread use of phenylurea herbicides (PHs) is a serious threat to human health and environmental safety. These pollutants usually have similar molecular structures but distinct toxicities. Therefore, developing rapid detection methods to analyze PHs quantitatively and qualitatively is highly desirable. This study fabricated a microfluidic glass liquid chromatography (LC) coupled with electrochemical detection (ECD) and Surface-Enhanced Raman spectroscopy (SERS) synchronous system, which demonstrated excellent separation and analysis performance for PHs. The complete separation of three PHs could be achieved using the microfluidic chip LC with a theoretical plate number of 342525 plates m–1. The limit of detection (LOD) of the PHs for optimized electrochemical analysis reached 0.0099–0.1388 mmol/L. More importantly, the detection system integrated with ECD and SERS had high sensitivity and molecular recognition ability, with intra and inter-day precision of less than 6.7630% and 7.5601%, respectively. The recovery of the PHs could reach 102.9861% when this detection system was applied to the analysis of soil extracts in the small potted plant and actual water samples in the environment. It is expected that the microfluidic chip with the LC-ECD-SERS synchronous detection system has significant potential in various environmental, food safety, drug, and biomedical analyses.

DNA framework-controlled Poly(MOFs) as a visual platform for diagnosis of HER2-positive breast cancer

The controllable assembly of metal-organic frameworks (MOFs) nanomaterials is an effective means to enhance their application capabilities. In this paper, a novel method is reported to control MOFs assembly by using a DNA framework material, a tetrahedral DNA nanostructure (TDN) labeled with phosphate groups at the vertex. In particular, various well-defined superstructures can be tailored by regulating the number of phosphate groups that coordinate with catalytic Zr-MOFs to create polymeric MOFs superstructures (Poly(MOFs)), exhibiting excellent catalytic activities and molecular recognition ability as well as greatly amplified signal readout. Furthermore, based on the DNA framework-controlled Poly(MOFs), a colorimetric biosensor with excellent analytical performance is fabricated for improving the diagnosis of human epidermal growth factor receptor 2 (HER2)-positive breast cancer. It is demonstrated that the quantification of HER2 protein can be achieved at molecular level with the limit of detection (LOD) of 12 pg L-1 and cellular level with the LOD of 10 cells. More importantly, the detection of HER2 in the serum of breast cancer patients have been achieved, thus HER2-positive and triple-negative breast cancer patients can be well distinguished. Considering the substitutability of the target, this study shows great potential in biomedical research as well as clinical applications.

Lithographically defined encoded magnetic heterostructures for the targeted screening of kidney cancer.

Renal cell carcinoma (RCC) is the 7th commonest cancer in the UK and the most lethal urological malignancy; 50% of all RCC patients will die from the condition. However, if identified early enough, small RCCs are usually cured by surgery or percutaneous procedures, with 95% 10 year survival. This study describes a newly developed non-invasive urine-based assay for the early detection of RCC. Our approach uses encoded magnetically controllable heterostructures as a substrate for immunoassays. These heterostructures have molecular recognition abilities and embedded patterned codes for a rapid identification of RCC biomarkers. The magnetic heterostructures developed for this study have a magnetic configuration designed for a remote multi axial control of their orientation by external magnetic fields, this control facilitates the code readout when the heterostructures are in liquid. Furthermore, the optical encoding of each set of heterostructures provides a multiplexed analyte capture platform, as different sets of heterostructures, specific to different biomarkers can be mixed together in a patient sample. Our results show a precise magnetic control of the heterostructures with an efficient code readout during liquid immunoassays. The use of functionalised magnetic heterostructures as a substrate for immunoassay is validated for urine specimen spiked with recombinant RCC biomarkers. Initial results of the newly proposed screening method on urine samples from RCC patients, and controls with no renal disorders are presented in this study. Comprehensive optimisation cycles are in progress to validate the robustness of this technology as a novel, non-invasive screening method for RCC.

Light-regulated morphology control in supramolecular polymers.

Stimuli-responsive materials have gained significant recent interest owing to their versatility and wide applications in fields ranging from materials science to biology. In the majority of examples, external stimuli, including light, act as a remote source of energy to depolymerize/deconstruct certain nanostructures or provide energy for exploring their functional features. However, there is little emphasis on the creation and precise control of these materials. Although significant progress has been made in the last few decades in understanding the pros and cons of various directional non-covalent interactions and their specific molecular recognition ability, it is only in the recent past that the focus has shifted toward controlling the dimension, dispersity, and other macroscopic properties of supramolecular assemblies. Control over the morphology of supramolecular polymers is extremely crucial not only for material properties they manifest but also for effective interactions with biological systems for their potential application in the field of biomedicine. This could effectively be achieved using photoirradiation which has been demonstrated by some recent reports. The concept as such offers a broad scope for designing versatile stimuli-responsive supramolecular materials with precise structure-property control. However, there has not yet been a compilation that focuses on the present subject of employing light to impact and regulate the morphology of supramolecular polymers or categorize the functional motif for easy understanding. In this review, we have collated recent examples of how light irradiation can tune the morphology and nanostructures of supramolecular polymers and categorized them based on their chemical transformation such as cis-trans isomerization, cycloaddition, and photo-cleavage. We have also established a direct correlation among the structures of the building blocks, mesoscopic properties and functional behavior of such materials and suggested future directions.

Enhanced molecular recognition with longer chain crosslinkers in molecularly imprinted polymers for an efficient separation of TR active substances.

Molecular imprinting technology has been widely studied as a technique to obtain molecular recognition by artificial means. Selecting functional monomers or polymerization conditions plays a key role to optimize molecularly imprinted polymer (MIP) synthesis. To date, there have been few reports well exploiting the effect of crosslinkers. Here, in this study, we synthesized the MIPs using poly(ethyleneglycol) dimethacrylate with different units of ethylene oxide (n = 1 to 23) as crosslinkers to observe the molecular recognition abilities. The MIPs were attached to the surface of mono-dispersed polymer beads. The obtained spherical MIPs and non-imprinted polymers were filled in a column for high performance liquid chromatography. Then the retention selectivity toward TR active substances was evaluated. The result revealed that the recognition ability did not improve regardless of the amount of ethylene oxide. With the crosslinker (n = 9), extremely high retention selectivity was observed, which provides at most around ten times as large imprinting factors in comparison with other MIPs. Interestingly, we obtained the highest recognition ability at around polymerization temperature from the evaluation of the recognition ability toward temperature shift using the MIP (n = 9). In general, hydrogen bonding based on MIPs provides high recognition ability at low temperature, whereas, this study indicates that the use of flexible crosslinkers may enable the synthesis of MIPs that precisely memorize the conditions of polymerization. Lastly, we simultaneously analyzed the TR active substances using the column filled with MIPs (n = 9). The result showed relatively linear correlation between the retention strength of each substance and phycological activity toward TR obtained by yeast assay. Therefore, we can conclude that an induced fit like the receptor emerged by constructing the flexible molecular recognition field.

Synthesis, conformational properties, and molecular recognition abilities of novel prism[5]arenes with branched and bulky alkyl groups

The direct macrocyclization to prism[5]arenes of 2,6-dialkoxynaphthalenes with branched and bulky alkyl groups has been obtained in good yields. The chirality of these novel prism[5]arenes is stable on the NMR time scale.

Immobilization of two dendritic organic phases onto silica and their molecular shape recognition for polycyclic aromatic hydrocarbons, tocopherols and carotenoid isomers

BackgroundMolecular shape selectivity, based on the size and shape parameters of the molecule, such as length and planarity, is a separation process that can be used for compounds with restricted shapes, such as isomers. The separation of geometric isomers is challenging because these compounds have similar physicochemical properties but differ slightly in molecular shape. The ability to separate and quantify these isomers is important in high performance liquid chromatography (HPLC), which is one of the most widely used techniques in separation science today, because the shape of the molecule has a strong influence on biological processes. ResultsWe prepared symmetrical discoidal dendrimeric organomolecule gelators (GSDM) and o-phenylenediamine-derived low-molecular-weight dendrimeric organomolecule gelators (G1) and bonded them to silica surfaces. The dendritic organic compound-grafted silica (SiO2@GSDM and SiO2@G1) was used as HPLC stationary phases for the separation of shape-restricted isomers of polycyclic aromatic hydrocarbons (PAHs), carotenoids and tocopherols. The two phases exhibit a very high molecular shape selectivity compared to the commercially available alkyl phases. There are differences in molecular shape selectivity between the two stationary phases. Changes in the chemical structure of dendritic organic compounds can alter the orientation of the molecules, as well as changes in the molecular recognition ability. It was found that SiO2@GSDM has high molecular linear selectivity for PAHs at different temperatures, even at 50 °C. The planar selectivity of SiO2@GSDM was better for triphenylene and o-terphenyl benzenes compared to SiO2@G1. SignificanceThis separation behavior may be attributed to the combined effect of weak interaction centers, which allowed the effective separation of bioactive and shape-restricted isomers through multiple interactions. Furthermore, SiO2@GSDM showed better separation of tocopherols and carotenoids, suggesting that the backbone and ordered structure of organic molecular gelators is an effective way to improve the shape selectivity of the molecules, whereas the molecular orientation of the functional groups influences the separation mechanism of the shape-restricted isomers.

Advances in Nucleic Acid Research: Exploring the Potential of Oligonucleotides for Therapeutic Applications and Biological Studies.

In recent years, nucleic acids have emerged as powerful biomaterials, revolutionizing the field of biomedicine. This review explores the multifaceted applications of nucleic acids, focusing on their pivotal role in various biomedical applications. Nucleic acids, including deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), possess unique properties such as molecular recognition ability, programmability, and ease of synthesis, making them versatile tools in biosensing and for gene regulation, drug delivery, and targeted therapy. Their compatibility with chemical modifications enhances their binding affinity and resistance to degradation, elevating their effectiveness in targeted applications. Additionally, nucleic acids have found utility as self-assembling building blocks, leading to the creation of nanostructures whose high order underpins their enhanced biological stability and affects the cellular uptake efficiency. Furthermore, this review delves into the significant role of oligonucleotides (ODNs) as indispensable tools for biological studies and biomarker discovery. ODNs, short sequences of nucleic acids, have been instrumental in unraveling complex biological mechanisms. They serve as probes for studying gene expression, protein interactions, and cellular pathways, providing invaluable insights into fundamental biological processes. By examining the synergistic interplay between nucleic acids as powerful biomaterials and ODNs as indispensable tools for biological studies and biomarkers, this review highlights the transformative impact of these molecules on biomedical research. Their versatile applications not only deepen our understanding of biological systems but also are the driving force for innovation in diagnostics and therapeutics, ultimately advancing the field of biomedicine.