UiO66-based molecularly imprinted polymers with water-compatible deep eutectic solvent as functional monomer for purification of lysozyme from egg white.

Protein-templated molecularly imprinted polymers have limitations such as poor mass transfer, slow recognition kinetics, and difficulties in isolation and purification due to their large molecular sizes, complex structures, and flexible conformations. To address these limitations and obtain lysozyme (Lyz)-imprinted polymers, a molecularly imprinted polymer (UiO66@DES-MIPs) was prepared for the first time by using Lyz as a template molecule, a metal-organic framework (UiO66-NH2) as a matrix, and a water-compatible deep eutectic solvent (DES) as a functional monomer. The introduction of UiO66-NH2 by the solvothermal method with a large specific surface area and favorable stability and resistance to environmental disturbances into the MIPs can reduce the "embedding" phenomenon and acquire a higher binding capacity and fast mass transfer. In addition, a water-soluble binary DES (1:2 molar ratio of choline chloride to 1,3 dimethylurea) prepared by a hydrothermal method as a functional monomer generates multiple forces with Lyz, increasing the hydrophilicity of UiO66@DES-MIPs and contributing to the formation and stabilization of the imprinted sites. Consequently, UiO66@DES-MIPs exhibited good selectivity, water compatibility, and fast adsorption equilibrium (the adsorption equilibrated at 243.87 ± 4.88 mg g-1 in 90 min). Besides, reusability experiments indicated that the UiO66@DES-MIPs could be recycled six times without obvious loss of adsorption capacity. The imprinting factor of UiO66@DES-MIPs is 3.67. The isolation and purification of Lyz from egg white confirmed the practicability of UiO66@DES-MIPs. The high adsorption capacity and specific recognition make this polymer a promising candidate for the isolation and purification of biological macromolecules.

Application effect of computer-aided design combined with three-dimensional printing technology in autologous tooth transplantation: a retrospective cohort study.

BACKGROUND: The activity of donor periodontal membrane is the key factor of autologous tooth healing. The application of digital aided design, 3D printing model and guide plate in autotransplantation of tooth (ATT) is expected to reduce the damage of periodontal membrane and preserve the activity of periodontal membrane, so as to improve the success rate of ATT. This study tried to prove the role of digital technology in improving the success rate of ATT, although there are differences in model accuracy in practice. METHODS: We included 41 tooth autotransplantation cases which assisted by 3D-printed donor models and surgical guides and divided them into two groups in accordance with whether the donor tooth could be placed successfully after the preparation of alveolar socket guided by the model tooth. Then, we compared and analyzed the preparation time of alveolar socket, extra-alveolar time, and number of positioning trials of the donor tooth between the two groups. We also included a comparison of the in vitro time of the donor tooth with that of 15 min. The incidence of complications was included in the prognostic evaluation. RESULTS: The mean preparation time of the alveolar socket, mean extra-alveolar time of donor tooth, and mean number of positioning trials with donor tooth of 41 cases were 12.73 ± 6.18 min, 5.56 ± 3.11 min, and 2.61 ± 1.00, respectively. The group wherein the donor tooth cannot be placed successfully (15.57 ± 6.14 min, 7.29 ± 2.57 min) spent more preparation time of alveolar socket and extra-alveolar time than the group wherein the donor tooth can be placed successfully (9.75 ± 4.73 min, 3.75 ± 2.57 min). The number of positioning trials with the donor tooth of the group wherein the donor tooth cannot be placed successfully (3.19 ± 0.75) was higher than that of the other group (2.00 ± 0.86). There was no significant difference in survival rates between the two groups. CONCLUSIONS: Compared with the traditional tooth autotransplantation, the introduction of computer-aided design combined with 3D printing of the model tooth and surgical guides evidently shortens the preparation time of the alveolar socket and the extra-alveolar time of the donor tooth and reduces the number of positioning trials with the donor tooth regardless of the shape deviation between the model and actual teeth.

A molecularly imprinted polymer based on MOF and deep eutectic solvent for selective recognition and adsorption of bovine hemoglobin.

In this study, a novel kind of imprinted polymers based on metal-organic frameworks (MOF@DES-MIPs) was prepared, using bovine hemoglobin (BHb) as template molecules and deep eutectic solvents (DES) as functional monomers for selective recognition and adsorption of BHb. MOF were used as the substrates to improve the accessibility of imprinted sites and DES as the functional monomers to produce different forces for BHb to help the formation of imprinted sites. Imprinted polymer films were taken to provide analyte selectivity. The MOF@DES-MIPs prepared were characterized and evaluated by scanning electron microscope, X-ray diffraction, and Fourier transform infrared spectrometer. We also investigated the influences of BHb concentration and adsorption time on the performance of MOF@DES-MIPs. The maximal adsorption capacity of MOF@DES-MIPs to BHb reached 151.28 mg g-1, and the MOF@DES-MIPs showed good selectivity and fast adsorption equilibrium, which might offer a novel method for the preparation and research of molecularly imprinted polymers of biomacromolecules. In addition, MOF@DES-MIPs were successfully applied in the selective recognition of BHb from a real bovine blood sample. Graphical abstract.

Recent Advances in Electrochemiluminescence and Chemiluminescence of Metal Nanoclusters.

Metal nanoclusters (NCs), including Au, Ag, Cu, Pt, Ni and alloy NCs, have become more and more popular sensor probes with good solubility, biocompatibility, size-dependent luminescence and catalysis. The development of electrochemiluminescent (ECL) and chemiluminescent (CL) analytical methods based on various metal NCs have become research hotspots. To improve ECL and CL performances, many strategies are proposed, from metal core to ligand, from intermolecular electron transfer to intramolecular electron transfer. Combined with a variety of amplification technology, i.e., nanostructure-based enhancement and biological signal amplification, highly sensitive ECL and CL analytical methods are developed. We have summarized the research progresses since 2016. Also, we discuss the current challenges and perspectives on the development of this area.

Ultrasensitive detection of chlortetracycline in animal-origin food using molecularly imprinted electrochemical sensor based on SnS2/ZnCo-MOF and AuNPs.

The chlortetracycline (CTC) residue in food poses a threat to human health. Therefore, developing sensitive, convenient and selective analytical methods for CTC detection is crucial. This study innovatively uses tin disulfide/bimetallic organic framework (SnS2/ZnCo-MOF) nanocomposites in conjunction with gold nanoparticles (AuNPs) to co-modify a glassy carbon electrode (GCE). Further, a molecularly imprinted polymer (MIP)-based electrochemical sensing platform Au-MIP/SnS2/ZnCo-MOF/Au/GCE (AZG) was fabricated for selective CTC detection. SnS2/ZnCo-MOF enhanced the stability and surface area of the AZG sensor. The presence of AuNPs facilitated electron transport between the probe and the electrode across the insulating MIP layer. The fixation of AuNPs and MIP via electropolymerization enhanced the selective recognition of this sensor and amplified its output signal. The AZG sensor demonstrated a wide linear detection range (0.1-100 µM), low detection limit (0.072 nM), and high sensitivity (0.830 µA µM-1). It has been used for detecting CTC in animal-origin food with good recovery (96.08%-104.60%).

Efficacy of Polyethylene Glycol Electrolyte Powder Combined With Linaclotide for Colon Cleansing in Patients With Chronic Constipation Undergoing Colonoscopy: A Multicenter, Single-Blinded, Randomized Controlled Trial.

INTRODUCTION: Constipation is an independent risk factor for poor bowel preparation. This study aimed to evaluate the bowel cleansing efficacy and safety of polyethylene glycol (PEG) combined with linaclotide (lin) for colonoscopy in patients with chronic constipation (CC). METHODS: This single-blinded, randomized, controlled, and multicenter study was conducted from July 2021 to December 2022 at 7 hospitals. Patients with CC who underwent colonoscopies were enrolled and randomly assigned to 4 groups with split-PEG regimens: 4L-PEG group, 4L-PEG+1d-Lin group, 3L-PEG+1d-Lin group, and 3L-PEG+3d-Lin group. The primary outcome was rates of adequate bowel preparation, defined as a total BBPS score ≥6 and a score ≥2 for each segment. Secondary outcomes were adverse effects, sleep quality, willingness to repeat the colonoscopy, adenoma detection rate, and polyp detection rate. RESULTS: Five hundred two patients were enrolled. The rates of adequate bowel preparation (80.0% vs 60.3%, P < 0.001; 84.4% vs 60.3%, P < 0.001) and the total Boston Bowel Preparation Scale (BBPS) scores (6.90 ± 1.28 vs 6.00 ± 1.61, P < 0.001; 7.03 ± 1.24 vs 6.00 ± 1.61, P < 0.01) in the 4L-PEG+1d-Lin group and the 3L-PEG+3d-Lin group were superior to that in the 4L-PEG group. Compared with the 4L-PEG group, the 4L-PEG+1d-Lin group (66.7% vs 81.7%, P = 0.008) and the 3L-PEG+3d-Lin group (75.0% vs 81.7%, P = 0.224) had a lower percentage of mild adverse events. No statistically significant difference in willingness to repeat the colonoscopy, sleep quality, polyp detection rate, or adenoma detection rate was observed among groups. DISCUSSION: PEG combined with linaclotide might be an effective method for bowel preparation before colonoscopy in patients with CC.

Biodegradable Imprinted Polymer Based on ZIF-8/DOX-HA for Synergistically Targeting Prostate Cancer Cells and Controlled Drug Release with Multiple Responses.

Improving the drug loading and delivery efficiency of biodegradable nanomaterials used for targeting prostate cancer (PCa) remains a challenging task. To accomplish this task, herein, a new surface molecularly imprinted polymer (ZIF-8/DOX-HA@MIP) was designed and constructed with a hyaluronic acid (HA)-modified zeolitic imidazolate framework-8 (ZIF-8) metal-organic framework loaded with doxorubicin (DOX) as a substrate and a responsive molecularly imprinted polymer film as a shell. Owing to the large surface area of ZIF-8, DOX was successfully loaded into the ZIF-8/DOX-HA@MIP with a high drug loading efficiency (more than 88%). In vitro cell experiments have shown that the strengthened targeting ability of ZIF-8/DOX-HA@MIP to PCa cells was realized through the synergistic effect of HA and the molecularly imprinted membrane. Under the condition of simulated tumor microenvironment solution, Zn species were released and the particle size of ZIF-8/DOX-HA@MIP decreased gradually by the synergistic effect of hyaluronidase, pH, and glutathione, showing excellent biodegradability. In vivo antitumor research indicated the excellent antitumor activity and biocompatibility of ZIF-8/DOX-HA@MIP. The multifunctional ZIF-8/DOX-HA@MIP constructed herein provides a novel impetus for the development of targeted drug delivery in PCa treatment and a new strategy for treating other tumors.

Molecularly imprinted electrochemical sensor based on synergistic interaction of honeycomb-like Ni-MOF decorated with AgNPs and N-GQDs for ultra-sensitive detection of olaquindox in animal-origin food.

Olaquindox (OLA) in food from its illegal use possesses great harmful effects on humans, making it important to develop sensitive, inexpensive, and convenient methods for OLA detection. This study innovatively presented a molecularly imprinted electrochemical sensor based on the synergistic effects of nitrogen-doped graphene quantum dots (N-GQDs) and a nickel-based metal-organic framework functionalized with silver nanoparticles (Ag/Ni-MOF) for OLA detection. N-GQDs and Ag/Ni-MOF with unique honeycomb structures were sequentially modified on the glassy carbon electrode (GCE) surface to accelerate the electron transfer rate and increase the available region of the electrode. Molecularly imprinted polymers were further grown on the Ag/Ni-MOF/N-GQDs/GCE by electropolymerization to significantly enhance the selective recognition of OLA. The constructed sensor showed excellent performance for selective OLA determination, with a wide linear range (5-600 nmol·L-1) and exceedingly low detection limit (2.2 nmol·L-1). The sensor was successfully applied to detect OLA in animal-origin food with satisfactory recoveries (96.22-101.02%).

Disulfide-Bridged Dendritic Organosilicas-Based Biodegradable Molecularly Imprinted Polymers for Multiple Targeting and pH/Redox-Responsive Drug Release toward Chemical/Photodynamic Synergistic Tumor Therapy.

In this study, a sialic acid (SA) and transferrin (TF) imprinted biodegradable disulfide bridging organosilicas-based drug delivery system (SS-DMONS/DOX-Ce6@MIPs) for targeted cancer therapy is constructed, for the first time. Disulfide bridged dendritic mesoporous organosilicas nanoparticles (SS-DMONs) not only enhance drug loading as the drug repository, but also provide enough specific surface area for the molecular imprinting shell to expose more degradation and imprinted sites on the surface. In addition, SS can be disturbed in a highly reducing tumor microenvironment to achieve degradation. The biodegradable imprinting film, prepared with customized 2-amino-N-(3,4-dihydroxyphenethyl)-3-mercaptopropanamide and 4-mercaptophenylboronic acid as functional monomers, endows SS-DMONs with active targeting capacity, and responsive drug release through degradation under acidic and highly reductive tumor microenvironment. SS-DMONS/DOX-Ce6@MIPs after binding of TF can target tumor cells actively through multiple interactions, including the affinity between antigen and antibody, and the specific recognition between molecularly imprinted polymers and template molecules. Under laser irradiation the loaded chlorin e6 (Ce6) that can produce toxic reactive oxygen, combined with the doxorubicin (DOX), achieves chemical/photodynamic synergistic anticancer effects. SS-DMONS/DOX-Ce6@MIPs present excellent tumor targeting and dual-responsive drug release, which provides an effective strategy for chemical/photodynamic antitumor therapy.

Programmed release of vascular endothelial growth factor and exosome from injectable chitosan nanofibrous microsphere-based PLGA-PEG-PLGA hydrogel for enhanced bone regeneration.

The healing of large bone defects remains a significant challenge in clinical practice. Accelerating both angiogenesis and osteogenesis can promote effective bone healing. In the natural healing process, angiogenesis precedes osteogenesis, providing a blood supply that supports the subsequent progression of osteogenesis. Developing a biomimetic scaffold that mimics the in vivo environment and promotes the proper sequence of vascularization followed by ossification is crucial for successful bone regeneration. In this study, a novel injectable dual-drug programmed releasing chitosan nanofibrous microsphere-based poly(D, l-lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(D,l-lactide-co-glycolide) (PLGA-PEG-PLGA) hydrogel is fabricated by incorporating vascular endothelial growth factor (VEGF) and microspheres loaded with dental pulp stem cells-derived exosomes (DPSCs-Exo). Rapid release of VEGF promotes the swift initiation of angiogenesis, while DPSCs-Exo release ensures persistent osteogenesis. Our results demonstrate that chitosan microsphere-based PLGA-PEG-PLGA hydrogel significantly promotes angiogenesis in human umbilical vascular endothelial cells and enhances the osteogenic differentiation of pre-osteoblasts. Furthermore, in vivo transplantation of this injectable chitosan microsphere-based PLGA-PEG-PLGA hydrogel into calvarial bone defects markedly promotes bone formation. Overall, our study provides a promising approach for improving bone regeneration by temporally replicating the behavior of angiogenesis and osteogenesis.

Co-delivery of curcumin and epigallocatechin gallate in W/O/W emulsions stabilized by protein fibril-cellulose complexes.

Hydrophobic curcumin and hydrophilic epigallocatechin gallate (EGCG) are reported to exhibit a variety of biological activities and may exhibit synergistic effects when used in combination. A co-encapsulation system was developed to improve their applicability and bioavailability. This delivery system consisted of a water-in-oil-in-water (W1/O/W2) double emulsion stabilized by whey protein isolate fibrils (WPIFs) and cellulose nanocrystals (CNCs). Double emulsions were fabricated using a two-step emulsification method using either WPIF-CNC complexes or WPIF alone. The physicochemical stability, encapsulation performance, and digestive properties of the delivery systems were then investigated. The double emulsions stabilized by the WPIF-CNC complexes were more resistant to heat and salt stress, exhibited greater encapsulation stability, and had a higher bioaccessibility for curcumin (67.8%) and EGCG (68.9%) than those stabilized by WPIFs. This research shows that the stability and bioaccessibility of curcumin and EGCG can be enhanced by co-encapsulating them in emulsion-based delivery systems using nanostructured protein-polysaccharide complexes.

Double Candida antarctica lipase B co-display on Pichia pastoris cell surface based on a self-processing foot-and-mouth disease virus 2A peptide.

To develop a high efficiency Candida antarctica lipase B (CALB) yeast display system, we linked two CALB genes fused with Sacchromyces cerevisiae cell wall protein genes, the Sed1 and the 3'-terminal half of Sag1, separately by a 2A peptide of foot-and-mouth disease virus (FMDV) in a single open reading frame. The CALB copy number of recombinant strain KCSe2ACSa that harbored the ORF was identified, and the quantity of CALB displayed on the cell surface and the enzyme activity of the strain were measured. The results showed that the fusion of multiple genes linked by 2A peptide was translated into two independent proteins displayed on the cell surface of stain KCSe2ACSa. Judging from the data of immunolabeling assay, stain KCSe2ACSa displayed 94 % CALB-Sed1p compared with stain KCSe1 that harbored a single copy CALB-Sed1 and 64 % CALB-Sag1p compared with stain KCSa that harbored a single copy CALB-Sag1 on its surface. Besides, strain KCSe2ACSa possessed 170 % hydrolytic activity and 155 % synthetic activity compared with strain KCSe1 as well as 144 % hydrolytic activity and 121 % synthetic activity compared with strain KCSa. Strain KCSe2ACSa even owned 124 % hydrolytic activity compared with strain KCSe2 that harbored two copies CALB-Sed1. The heterogeneous glycosylphosphatidylinositol-anchored proteins co-displaying yeast system mediated by FMDV 2A peptide was shown to be an effective method for improving the efficiency of enzyme-displaying yeast biocatalysts.

Preparation of mesh covalent organic framework Tppa-2-based adsorption enhanced magnetic molecularly imprinted composite for selective extraction of tetracycline residues from animal-derived foods.

In this study, for the first time, core-shell tetracycline hydrochloride-molecularly imprinted polymers (MIPs) were prepared by precipitation polymerization using a magnetic covalent organic framework (Fe3O4@Tppa-2) synthesized by room-temperature ultrasonic method as a substrate. Introducing Fe3O4@Tppa-2 into the molecular imprinting system can be used for efficient shortens the time for the adsorption equilibrium of MIPs due to its unique pore structure. The maximum adsorption capacity of MIPs was 87.50 mg/g, and the adsorption equilibrium reached in 14 min. The MIPs were used as magnetic solid-phase extraction sorbents in combination with high performance liquid chromatography for the determination of tetracycline in pork, chicken and chicken liver, and the detection limit reached 0.01 ng/mL. In addition, the adsorption advantages of MIPs suggest that it is a promising adsorbent for the recovery of antibiotics and has potential applications in the detection and enrichment of TC in food.

Liposomes encapsulating artificial cytosol as drug delivery system.

The fabrication of cell models containing artificial cytosol is challenging. Herein we constructed an artificial cytosol contained cell model by electroformation method. Agarose was selected as the main component of the artificial cytosol, and sucrose was added into the agarose to regulate the sol viscosity and the phase transition temperature. The viscosity of the sol with the mass ratio (agarose-sucrose) 1:9 was closest to the natural cytosol. DSPC/20 mol% cholesterol was used to form large unilamellar vesicles (LUVs) as cell model compartment. The rhodamine release experiment confirmed that the unique release profile of agarose-sucrose@LUVs is suitable as a drug carrier. Doxorubicin is loaded in the agarose-sucrose@LUVs, and their half maximum inhibition concentration on HeLa cells is 0.016 µmol L-1, which means 28.7 times increase in inhibition efficiency over free doxorubicin.

Enhancing emulsion stability and performance using dual-fibrous complexes: Whey protein fibrils and cellulose nanocrystals.

Edible proteins can self-assemble into fibrils, which can improve their performance as emulsifiers. However, they are limited in some food applications. We prepared whey protein isolate fibril-cellulose nanocrystal complexes (WPIF-CNC) by electrostatic complexation. The stabilities of emulsions prepared using either WPIF or WPIF-CNC were compared to evaluate the effect of complexation on emulsion formation and properties. Moreover, the potential of the emulsions to act as delivery systems for curcumin was investigated. WPIF and CNC were found to complex by hydrogen bonding, hydrophobic, and electrostatic interactions. The complexes formed were good Pickering stabilizers in oil-in-water emulsions. Emulsions formulated using the complexes were more resistant to creaming than those stabilized by WPIF. The complexes were able to form self-supporting gelled emulsions at 70 % oil concentration, which protected curcumin from photo- and thermal-degradation. Consequently, dual-fibrous complexes may have application in the food industry as novel emulsifiers for the creation of nutraceutical delivery systems.

Mussel-inspired functionalization of electrospun scaffolds with polydopamine-assisted immobilization of mesenchymal stem cells-derived small extracellular vesicles for enhanced bone regeneration.

Mesenchymal stem cells-derived small extracellular vesicles (MSCs-sEV) have shown promising prospects as a cell-free strategy for bone tissue regeneration. Here, a bioactive MSCs-sEV-loaded electrospun silk fibroin/poly(ε-caprolactone) (SF/PCL) scaffold was synthesized via a mussel-inspired immobilization strategy assisted by polydopamine (pDA). This pDA modification endowed the as-prepared scaffold with high loading efficiency and sustained release profile of sEV. In addition, the fabricated composite scaffold exhibited good physiochemical, mechanical, and biocompatible properties. In vitro cellular experiments indicated that the MSCs-sEV-loaded composite scaffold promoted the adhesion and spreading of preosteoblast and endothelial cells, as well as enhanced osteogenic differentiation and angiogenic activity. In vivo experiments showed that the functionalized electrospun scaffolds promoted bone regeneration in a rat calvarial bone defect model. Results suggest that the developed MSCs-sEV-anchored pDA-modified SF/PCL electrospun scaffolds possess high application potential in bone tissue engineering owing to their powerful pro-angiogenic and -osteogenic capacities, cell-free bioactivity, and cost effectiveness.

Emerging role of exosomes in craniofacial and dental applications.

Exosomes, a specific subgroup of extracellular vesicles that are secreted by cells, have been recognized as important mediators of intercellular communication. They participate in a diverse range of physiological and pathological processes. Given the capability of exosomes to carry molecular cargos and transfer bioactive components, exosome-based disease diagnosis and therapeutics have been extensively studied over the past few decades. Herein, we highlight the emerging applications of exosomes as biomarkers and therapeutic agents in the craniofacial and dental field. Moreover, we discuss the current challenges and future perspectives of exosomes in clinical applications.

[Clinical study of digital clear aligner treatment of 33 adult periodontal disease patients with malocclusion].

PURPOSE: The purpose of this study was to investigate the periodontal status in adult periodontal disease patients with malocclusion treated with digital clear aligners. METHODS: Thirty-three patients with periodontal disease who needed orthodontic treatment were selected. The patients were randomly divided into 2 groups, digital clear aligners group (experimental group, 16 patients) and fixed appliances group (control group, 17 patients). Bleeding index (BI), probing depth(PD), plaque index(PLI) and gingival index(GI) were recorded at baseline and 1, 3, 6 and 9 months during orthodontic treatment. SPSS 17.0 software package was used to analyze and compare the data of periodontal status between two groups. RESULTS: 1, 3, 6, and 9 months after orthodontic treatment, clinical parameters of the control group were significantly higher than baseline(P<0.05). The same measurements of the experimental group showed no significant differences at 1, 3, 6, and 9 months of treatment (P>0.05). After 1, 3, 6, and 9 months of treatment, the clinical parameters of BI, PLI and GI in the experimental group were significantly lower than the control group(P<0.05); PD in the experimental group was smaller than the control group, but there was no significant difference(P>0.05). CONCLUSIONS: Compared with conventional fixed appliance, clear aligner of digitalization can more effectively maintain periodontal heath in adult periodontal disease patients with malocclusion.

Latent Redox Reporter of 4-Methoxyphenol as Electrochemical Signal Proxy for Real-Time Profiling of Endogenous H2O2 in Living Cells.

Hydrogen peroxide (H2O2) plays a persuasive role in the human cell physiology. Developing an efficient assay platform and a highly sensitive tracking and quantification of H2O2 in a physiological system is crucial to understand the neoplastic changes and/or redox homeostasis of cells. In this study, a novel turn-on latent electrochemical redox probe coupled with electrocatalytic signal amplification strategy is proposed. A custom-made readily available turn-on latent electrochemical probe 4-methoxyphenylboronic acid pinacol ester (4-MPBP) have been designed for the selective detection of endogenous H2O2 in live cells. The electrochemical probe composed of a latent electrochemical reporter (4-methoxy phenol, 4-MP) bearing a recognition unit (boronic acid pinacol ester) for H2O2 sensing. The selective analyte-triggered chemical transformation releases free electrochemical reporter 4-MP. The amount of H2O2 was evaluated electrochemically at glassy carbon electrode (GCE) with a broad detection range of 0.5 µM-1 mM. An amplified signal response of released 4-MP to build a highly sensitive assay tool has been achieved via replacing the GCE transducer electrode with polydopamine@carbonnanotube-molebtinumdisulfie hybrid modified GCE as it delivered an exceptional dynamic detection range of 0.01-100 µM. The innovative blend of electrochemical molecular probe strategy, with electrocatalytic signal amplification technique has delivered outstanding assay performance at trace level sensing of H2O2. Next, we set up a platform for real-time in vivo monitoring of the endogenously produced H2O2 in Caco-2 and MCF-7 cells through spermine-polyamine analogue and phorbol 12-myristate 13-acetate induction in SSAT/PAO gene and protein kinase C, respectively. As expected, the 4-MPBP latent probe coupled with electrocatalytic signal amplification strategy delivered outstanding performance for in situ H2O2 release and tracking over time.

Development of a polysaccharide based multi-unit nanofiber mat for colon-targeted sustained release of salmon calcitonin.

Advances in pharmaceutical technology have promoted the development of colon-targeted delivery system for oral administration of bioactive peptides or proteins to enhance their bioavailability. In this study, a multi-unit nanofiber mat was fabricated by coaxial electrospinning and its feasibility as the colon-targeted delivery system for a bioactive peptide, salmon calcitonin (sCT), was investigated. Sodium alginate and sCT-loaded liposome coated with pectin served as the shell layer and core layer, respectively. An in vitro study demonstrated that the encapsulated sCT was released in a sustained and colon-targeted way. Analysis using different mathematical models showed that release followed a complex mechanism. In addition, greater amounts of sCT were released from the core-shell nanofiber mat into simulated colon fluid (SCF) than was released from a uniaxial nanofiber mat (65.2% vs. 47.8%). The use of a core-shell nanofiber mat further alleviated the burst release of sCT into simulated gastric and intestinal fluid (SGF and SIF), demonstrating the superiority of a multi-unit vehicle for colon-targeted delivery of sCT. Furthermore, 88% of the bioactivity of encapsulated sCT was retained. This multi-unit vehicle offers a better-designed vehicle for the colon-targeted sustained release of bioactive peptides or proteins and, thus, should improve oral bioavailability.