Preparation of Ionically Cross-Linked Pectin Nanoparticles in the Presence of Chlorides of Divalent and Monovalent Cations

Pectin nanoparticles loaded with nitric oxide donor drug: A potential approach for tissue regeneration

The process of wound healing and tissue regeneration involves several key mechanisms to ensure the production of new tissues with similar cellular functions. This study investigates the impact of pectin, a natural polysaccharide, and nebivolol hydrochloride (NBV), a nitric oxide (NO) donor drug, on wound healing. Utilizing ionotropic gelation, NBV-loaded pectin nanoparticles were developed following a 2231 full factorial design. The optimized formulation, determined using Design expert® software, exhibited an encapsulation efficiency percentage of 70.68%, zeta potential of -51.4 mV, and a particle size of 572 nm, characterized by a spherical, discrete morphology. An in vivo study was conducted to evaluate the effectiveness of the optimal formulation in wound healing compared to various controls. The results demonstrated the enhanced ability of the optimal formulation to accelerate wound healing. Moreover, histopathological examination further confirmed the formulation's benefits in tissue proliferation and collagen deposition at the wound site 15 days post-injury. This suggests that the developed formulation not only promotes faster healing but does so with minimal side effects, positioning it as a promising agent for effective wound healing and tissue regeneration.

How to Develop Drug Delivery System Based on Carbohydrate Nanoparticles Targeted to Brain Tumors

Brain tumors are the most difficult to treat, not only because of the variety of their forms and the small number of effective chemotherapeutic agents capable of suppressing tumor cells, but also limited by poor drug transport across the blood-brain barrier (BBB). Nanoparticles are promising drug delivery solutions promoted by the expansion of nanotechnology, emerging in the creation and practical use of materials in the range from 1 to 500 nm. Carbohydrate-based nanoparticles is a unique platform for active molecular transport and targeted drug delivery, providing biocompatibility, biodegradability, and a reduction in toxic side effects. However, the design and fabrication of biopolymer colloidal nanomaterials have been and remain highly challenging to date. Our review is devoted to the description of carbohydrate nanoparticle synthesis and modification, with a brief overview of the biological and promising clinical outcomes. We also expect this manuscript to highlight the great potential of carbohydrate nanocarriers for drug delivery and targeted treatment of gliomas of various grades and glioblastomas, as the most aggressive of brain tumors.

A Review of Pectin-Based Material for Applications in Water Treatment

Climate change and water are inseparably connected. Extreme weather events cause water to become more scarce, polluted, and erratic than ever. Therefore, we urgently need to develop solutions to reduce water contamination. This review intends to demonstrate that pectin-based materials are an excellent route to detect and mitigate pollutants from water, with several benefits. Pectin is a biodegradable polymer, extractable from vegetables, and contains several hydroxyl and carboxyl groups that can easily interact with the contaminant ions. In addition, pectin-based materials can be prepared in different forms (films, hydrogels, or beads) and cross-linked with several agents to change their molecular structure. Consequently, the pectin-based adsorbents can be tuned to remove diverse pollutants. Here, we will summarize the existing water remediation technologies highlighting adsorption as the ideal method. Then, the focus will be on the chemical structure of pectin and, from a historical perspective, on its structure after applying different cross-linking methods. Finally, we will review the application of pectin as an adsorbent of water pollutants considering the pectin of low degree methoxylation.

Cationic Chitosan/Pectin Polyelectrolyte Nanocapsules of Moxifloxacin as Novel Topical Management System for Bacterial Keratitis

PURPOSE

Moxifloxacin (MOX) is a fourth-generation fluoroquinolone and a broad spectrum antibiotic used in the management of bacterial keratitis (BK). This investigation aimed to formulate MOX-loaded chitosan/pectin cationic polyelectrolyte nanocapsules (CPNCs) for the effective topical treatment of BK.

METHODS

Physicochemical properties like nanocapsule size, charge, drug entrapment efficiency (EE), viscosity, pH, and in-vitro release profile of CPNCs were evaluated. The in-vitro antibacterial activity of CPNCs and marketed formulations (MFs) was studied against Staphylococcus aureus. Ex-vivo corneal permeation studies of CPNCs were evaluated with the help of a modified diffusion apparatus, which was used with goat cornea. The pharmacodynamic study was performed with optimized CPNCs on a BK-induced rabbit eye model and compared with MF.

RESULTS

The optimized nanocapsules appeared as positive charge (+19.91 ± 0.66) with a nano size (242.0 ± 0.30 nm) as calculated by the dynamic light scattering method. The in-vitro release profile of CPNCs exhibited sustained release properties. The ex-vivo permeation pattern also supported the improved drug permeation through the cornea from CPNCs as compared with MF. Draize irritation studies confirmed that the prepared formulation is compatible with the corneal tissue. The in-vivo study concluded that the antibacterial activity of CPNCs was improved when evaluated with MF.

CONCLUSION

The obtained results showed that CPNCs were the better choice for the management of BK therapy due to its capability to improve the corneal adhesion of CPNCs through direct interaction with the mucous membrane of the corneal tissue.

Structural properties of diluted alkali-soluble pectin from Pyrus communis L. in water and salt solutions

The self-assembly and gelation of low-methoxyl diluted alkali-soluble pectin (LM DASP) from pear fruit (Pyrus communis L. cv. Conference) was studied in water and salt solutions (NaCl and CaCl₂, constant ionic strength) without pH adjustment at 20 °C. The samples at different LM DASP concentrations were characterized using rheological tests, Fourier-transform infrared spectroscopy, dual-angle dynamic light scattering and atomic force microscopy. LM DASP from pear fruit (Pyrus communis L.) showed gelling ability. The indices (aggregation index and shape factor) based on light scattering may be useful for the characterization of structural changes in polysaccharide suspension, particularly for the determination of a gel point. The results obtained may be important for the food, cosmetic and pharmaceutical industries where pectin is used as a texturizer, an encapsulating agent, a carrier of bioactive substances or a gelling agent.

Current Advances in Lipid and Polymeric Antimicrobial Peptide Delivery Systems and Coatings for the Prevention and Treatment of Bacterial Infections

Bacterial infections constitute a threat to public health as antibiotics are becoming less effective due to the emergence of antimicrobial resistant strains and biofilm and persister formation. Antimicrobial peptides (AMPs) are considered excellent alternatives to antibiotics; however, they suffer from limitations related to their peptidic nature and possible toxicity. The present review critically evaluates the chemical characteristics and antibacterial effects of lipid and polymeric AMP delivery systems and coatings that offer the promise of enhancing the efficacy of AMPs, reducing their limitations and prolonging their half-life. Unfortunately, the antibacterial activities of these systems and coatings have mainly been evaluated in vitro against planktonic bacteria in less biologically relevant conditions, with only some studies focusing on the antibiofilm activities of the formulated AMPs and on the antibacterial effects in animal models. Further improvements of lipid and polymeric AMP delivery systems and coatings may involve the functionalization of these systems to better target the infections and an analysis of the antibacterial activities in biologically relevant environments. Based on the available data we proposed which polymeric AMP delivery system or coatings could be profitable for the treatment of the different hard-to-treat infections, such as bloodstream infections and catheter- or implant-related infections.

Effects of UV-C and Edible Nano-Coating as a Combined Strategy to Preserve Fresh-Cut Cucumber

The objective of this study was to evaluate the effectiveness of a combination of UV-C disinfection treatment and a nano-coating lemon essential oil nanocapsules. The nanocapsules were prepared by ionic gelation with an alginate-pectin wall and the lemon essential oil had a particle size of 219 ± 22 nm and a zeta potential of -7.91 ± 0.18 mV. The lemon essential oil had an encapsulation efficiency of 68.19 ± 1.18%. The fresh-cut cucumber was stored for 15 days at 4 °C. Six formulations of nanocapsules were evaluated, and hydroxypropyl methylcellulose was used as matrix polysaccharide in four coatings. Three formulations were treated with UV-C at 4.5 kJ/m². The results showed that the combination of UV-C and nano-coatings (lemon essential oil = 200 mg/L) increased the shelf life by up to 15 days. Using UV-C and nano-coatings, the ∆E value was 7.12 at the end of the storage period, while the Control samples had an ∆E of 28.1. With nano-coating treatment, the amount of polyphenols decreased by 23% within 9 days. In contrast, with combined UV-C and nano-coating treatment, the amount of polyphenols was reduced by 38.84% within 15 days. The antioxidant capacity remained stable at 459 μmol TE/100 g for the fresh product when the combined treatment was used. A good correlation was also observed between the increasing of the fruit's shelf life and decreasing of its enzymatic activity. The inclusion of UV-C treatment contributed to the reduction in the initial total bacteria at 3.30 log CFU/g and its combination with nano-coatings helped in the control of microbial growth during storage.

Engineering Polymeric Nanosystems against Oral Diseases

Nanotechnology and nanoparticles (NPs) are at the forefront of modern research, particularly in the case of healthcare therapeutic applications. Polymeric NPs, specifically, hold high promise for these purposes, including towards oral diseases. Careful optimisation of the production of polymeric NPs, however, is required to generate a product which can be easily translated from a laboratory environment to the actual clinical usage. Indeed, considerations such as biocompatibility, biodistribution, and biodegradability are paramount. Moreover, a pre-clinical assessment in adequate in vitro, ex vivo or in vivo model is also required. Last but not least, considerations for the scale-up are also important, together with an appropriate clinical testing pathway. This review aims to eviscerate the above topics, sourcing at examples from the recent literature to put in context the current most burdening oral diseases and the most promising polymeric NPs which would be suitable against them.

Evaluation of the physicochemical properties of pectin extracted from Musa paradisiaca banana peels at different pH conditions in the formation of nanoparticles

Colombia is one of the major producers and exporters of banana Musa paradisiaca. Its consumption is high then its agro-industrial wastes are important source to extract pectin. In the present study, inorganic acids (nitric acid and hydrochloride acid) and organic acids (citric acid and acetic acid) were evaluated to extract pectin from banana peels at pH 2 and 3, through acid hydrolysis during 1h at the temperature of 85 °C. The extraction yield, degree of esterification (DE) and intrinsic viscosity of the pectin were characterized. Nitric acid (NA) allowed to obtain higher extraction yield (54 ± 10%) and citric acid (CA) allowed to obtain higher DE (76.7 ± 2%). Additionally, the effect of polymer concentration and degree esterification, low degree of esterification (LDE, 33.1%) and high degree of esterification (HDE, 76.7%) were evaluated in the pectin nanoparticles formation. The pectin with HDE formed stable nanoparticles with a particle size of 255 ± 11 nm and the zeta potential value of -45 ± 3 mV, independently of the polymer concentration. Morphology analysis showed aggregated of the pectin nanoparticles.

Development of polymeric nanoparticle gel prepared with the combination of ionic pre-gelation and polyelectrolyte complexation as a novel drug delivery of timolol maleate

OBJECTIVE

The purpose of this study was to overcome the undesired systemic absorption of skin topical administration of timolol maleate (TM) by developing the TM nanoparticle gel.

METHODS

TM-loaded nanoparticle (TMNP) was prepared by ionic pre-gelation of pectin (PCN) and calcium ions (CI) followed with polyelectrolyte complex using chitosan (CHI). TMNP was characterized by measuring the particle size, polydispersity index, zeta potential, encapsulation efficiency (EE), and the interaction between formula constituents. TM-loaded nanoparticle gel (TMNG) was prepared by using hydroxypropyl methylcellulose (HPMC) and was characterized by measuring the spreadability, pH, viscosity, and drug content. The drug release kinetics were analyzed using DDSolver add-in program.

RESULTS

TMNP possessed particle size of 175.2 ± 19.7 nm, polydispersity index of 0.528 ± 0.113, zeta potential of -10.86 ± 0.87 mV, and EE of 27.45 ± 2.34%. The electrostatic interactions between PCN, CI, and CHI that formed the nanoparticles were confirmed by the result of vibrational spectroscopy analysis. TMNG possessed spreadability of 60.80 ± 1.38 cm², pH of 5.154 ± 0.004, viscosity of 269.07 ± 5.83 cP, and drug content of 107.38 ± 1.77%. TM showed a sustained release manner within 24 h by following Korsmeyer-Peppas kinetical model with non-Fickian release mechanism.

CONCLUSION

The prepared nanoparticle gel can be an effective controlled release system of TM that administered topically on the skin surface.

Impregnation of pectin-cedarwood essential oil nanocapsules onto mini cotton bag improves larvicidal performances

The use pesticide is one of the indispensable means to combat mosquito borne diseases. However, the repeated use of synthetic pesticides has induced resistance in the vector pest along with undesirable impact on the environment. The biodegradability, non-persistent and user’s safety are the root cause to prefer plant-derived pesticides to synthetic ones. The botanical based pesticides tend to degrade rapidly under the influence of several environmental factors. For the feasible application as pesticides, the plant products are formulated either as liquid or as purely solid. Despite well-established formulation technology in pesticide delivery, their handling trouble is being ignored. There is difficulty in liquid formulation of pesticide products, as they are prone to splashing and spillage, resulting in contamination, wastage and direct exposure to skin; whereas a solid formulation tends to produce dust. In the present work, cedarwood (Cedrus deodara) essential oil embedded pectin nanocapsules were produced. The nanocapsules were characterized according to their morphology, size, encapsulation efficiency and thermal stability. Furthermore, the nanocapsules were impregnated onto mini cotton tea bags to be employed as RTU (ready to use) formulation for treating the breeding sites of mosquitoes. The larvicidal activity of the bags treated with pectin-cedar wood nanocapsules was assessed against malaria vector, Anopheles culicifacies and 98% mortality was recorded till 4 weeks, this suggests its potential and hassle free applications in controlling mosquito vector.

Enhancement of Oral Bioavailability of Ibandronate Through Gastroretentive Raft Forming Drug Delivery System: In Vitro and In Vivo Evaluation

Background

Bisphosphonates have very low bioavailability and cause irritation of the esophagus and stomach. This study was planned to improve the oral bioavailability of ibandronate through the formation of a raft in the stomach. Bisphosphonate-induced irritation of the esophagus and stomach is prevented by the formation of a raft.

Materials and Methods

The nanostructured raft was developed through the use of nanosized citrus pectin (NCP). The particle size of NCP was measured by zeta sizer and SEM. The percentage of NCP and the neutralization profile of raft was studied. The ibandronate, polymers, and the developed formulation were characterized by FTIR, XRD, TGA, and DSC. The release of ibandronate was studied in 0.1 N HCl, 0.5 N HCl, 1 N HCl, and simulated gastric fluid (SGF) and a cell viability study was performed using Caco-2 cells. The PPR5 formulation and Bonish 150 mg tablets were selected as test and reference formulations, respectively, for pharmacokinetic study. Twelve healthy albino rats were taken and divided into two groups using a Latin square crossover design, and the blood samples were collected for 24 hours.

Results

The SEM image showed that the particle size of NCP was 159 nm. The raft of PPR5 showed 94% NCP and 45 minutes duration of neutralization. The FTIR and XRD showed chemical stability and a uniform distribution of ibandronate in the raft. The TGA and DSC indicated the thermal stability of formulation. The release of 99.87% ibandronate at 20 minutes was observed in the SGF. The values of C _max for the reference and test formulations were 493±0.237 ng/mL and 653±0.097 ng/mL, respectively. The AUC_(0-t) of the reference and test formulations was 3708.25±3.418 ng/mL.h and 6899.25±3.467 ng/mL.h, respectively.

Conclusion

The NCP has been successfully prepared from citrus pectin and has shown effective porous raft formation. The bioavailability of the ibandronate from newly developed PPR5 was higher than the already marketed formulation.

Polyelectrolyte-surfactant-complex nanoparticles as a delivery platform for poorly soluble drugs: A case study of ibuprofen loaded cetylpyridinium-alginate system

Previously, we reported on the surfactant cetylpyridinium chloride (CPC) as a crosslinker of alginate for the formation of stable polyelectrolyte-surfactant-complex nanoparticles. Here, we evaluate this system for increased solubility of a poorly soluble drug. The aim was to use CPC for solubilisation of ibuprofen and to use the micellar associates formed for alginate complexation and nanoparticle formation. We acquired deeper insights into the entropy led interactions between alginate, CPC and ibuprofen. Stable nanoparticles were formed across limited surfactant-to-polyelectrolyte molar ratios, with ~150 nm hydrodynamic diameter, monodispersed distribution, and negative zeta potential (-40 mV), with 34% ibuprofen loading. Their structure was obtained using small-angle X-ray scattering, which indicated disordered micellar associates when ibuprofen was incorporated. This resulted in nanoparticles with a complex nanostructured composition, as shown by transmission electron microscopy. Drug release from ibuprofen-cetylpyridinium-alginate nanoparticles was not hindered by alginate, and was similar to the release kinetics from ibuprofen-CPC solubilisates. These innovative carriers developed as polyelectrolyte-surfactant complexes can be used for solubilisation of poorly soluble drugs, where the surfactant simultaneously increases the solubility of the drug at concentrations below its critical micellar concentration and crosslinks the polyelectrolyte to form nanoparticles.

Pectin-Tannic Acid Nano-Complexes Promote the Delivery and Bioactivity of Drugs in Pancreatic Cancer Cells

Pancreatic cancer (PanCa) is a lethal disease. Conventional chemotherapies for PanCa offer severe systemic toxicities. Thus, the development of a successful nanomedicine-based therapeutic regimen with augmented therapeutic efficacy is highly sought. Naturally occurring pectin and modified pectin-based drug delivery systems exhibit remarkable self-targeting ability via galactose residues to various cancer cells. Herein, we developed and used an innovative approach of highly stable nanocomplexes based on modified pectin and tannic acid (MPT-NCs). The nanocomplex formation was enabled by strong intermolecular interactions between pectin and tannic acid under very mild conditions. These nanocomplexes were characterized by particle size and morphology (DLS, TEM, and SEM), FT-IR spectroscopy, and zeta potential measurements. Additionally, MPT-NCs were capable of encapsulating anticancer drugs (5-fluorouracil, gemcitabine, and irinotecan) through tannic acid binding. The in vitro bioactivity of these drug MPT-NCs were evaluated in pancreatic cancer adenocarcinoma (PDAC) cell lines (HPAF-II and PANC-1). A dose-dependent internalization of nanocomplexes was evident from microscopy and flow cytometry analysis. Both proliferation and colony formation assays indicated the anticancer potential of pectin drug nanocomplexes against PDAC cells compared to that of free drug treatments. Together, the pectin-based nanocomplexes could be a reliable and efficient drug delivery strategy for cancer therapy.

Essential oil loaded pectin/chitosan nanoparticles preparation and optimization via Box–Behnken design against MCF-7 breast cancer cell lines

In the continuous search for effective cancer treatments, we here report a novel anticancer nanoparticulate system composed of jasmine oil (JO), an essential oil with proven anticancer activity and pectin/chitosan composite nanoparticles (Pec/CS NPs) as encapsulating materials to overcome JO's solubility and sensitivity problems using a green ionotropic gelation method. Pec/CS/JO NPs were formulated using Box–Behnken design (BBD) to estimate the interactions and effects of studied formulation variables on particle size, zeta potential and encapsulation efficiency to develop an optimized Pec/CS nanoformulation. The nano-encapsulation system preserved the consistency of total phenolic contents in JO and amended its thermal stability by 1.64 fold. The antioxidant potency of JO was enhanced after encapsulation by 96.28%. Consequently, the cytotoxic activity of bare Pec/CS NPs, pure JO and encapsulated JO in Pec/CS NPs against (MCF-7) breast cancer cells and (L-929) normal cells was evaluated using MTT assay. Encapsulated JO was more potent than pure JO with ≈13 fold improvement in anticancer activity, whereas the cell viability of normal cells wasn't affected but was rather enhanced when treated with Pec/CS NPs.

Pec/CS/JO formulated nanocomposite showed a 13-fold increase in potency against cancer cells, whereas cell viability of normal cells wasn't affected.

Brinzolamide loaded chitosan-pectin mucoadhesive nanocapsules for management of glaucoma: Formulation, characterization and pharmacodynamic study

AIM

Brinzolamide (BNZ) is a carbonic anhydrase inhibitor commonly used for the treatment of glaucoma. The aim of this study was to prepare BNZ loaded chitosan-pectin mucoadhesive nanocapsules (CPNCs) by polyelectrolyte complex coacervation method for ocular delivery and evaluated for its anti glaucoma efficacy.

METHODS

The prepared CPNCs were characterized for their particle size, polydispersity index, zeta-potential, surface morphology, entrapment efficiency, drug loading efficiency, mucoadhesive strength in-vitro and ex-vivo release. The pharmacodynamic studies were conducted for CPNCs on glaucoma induced rabbit eye model and compared with marketed product.

RESULT AND DISCUSSION

All the formulated CPNCs exhibited the size range from 217.01 ± 0.21 to 240.05 ± 0.08 nm and appropriate physico-chemical parameters, and depicted a couple of erosion- diffusion release of BNZ over a time of 8 h. Ex-vivo corneal permeation study concluded that BNZ loaded CPNCs crosses the cornea potentially higher rate as compared to the marketed product. In pharmacodynamic study, greater intraocular pressure lowering effect was achieved by CPNCs as compared to marketed drug product.

CONCLUSION

The result concluded that CPNCs are a feasible choice to conventional eye drops because of its ability to improve the bioavailability via its longer precorneal retention time and its ability to sustained release of the drug.

Multi-scale pectin/polyphenol beads for non-fouling fluorescence tracking on soft matter under water

The smart polyphenol material could be designed to form two competitive interactions related to same one polyphenol molecule with different objects that could easily adhere to one surface through the weak interaction, and also could be entirely removed from the same surface by the strong interaction. In this study, the multi-scale pectin beads were fabricated by crosslinking with ions that could be acted as polyphenol loading agent through electrostatic force between the ions loading on the surface of pectin beads and polyphenol. The two effects on the size and appearance of pectin beads were detected. Because of the hydrogen bond between polyphenols loading on the beads and the surface of target, fluorescence-functionalized beads could easily adhere on target surfaces. Meanwhile, attributing to stronger electrostatic force between surface ions on beads and polyphenol, the thin membrane made of the beads can be entirely removed from the target surface to avoid the pollution of fluorescence probes.

Influence of Pectin Structural Properties on Interactions with Divalent Cations and Its Associated Functionalities

Pectin is an anionic cell wall polysaccharide which is known to interact with divalent cations via its nonmethylesterified galacturonic acid units. Due to its cation-binding capacity, extracted pectin is frequently used for several purposes, such as a gelling agent in food products or as a biosorbent to remove toxic metals from waste water. Pectin can, however, possess a large variability in molecular structure, which influences its cation-binding capacity. Besides the pectin structure, several extrinsic factors, such as cation type or pH, have been shown to define the cation binding of pectin. This review paper focuses on the research progress in the field of pectin-divalent cation interactions and associated functional properties. In addition, it addresses the main research gaps and challenges in order to clearly understand the influence of pectin structural properties on its divalent cation-binding capacity and associated functionalities. This review reveals that many factors, including pectin molecular structure and extrinsic factors, influence pectin-cation interactions and its associated functionalities, which makes it difficult to predict the pectin-cation-binding capacity. Despite the limited information available, determination of the cation-binding capacity of pectins with distinct structural properties using equilibrium adsorption experiments or isothermal titration calorimetry is a promising tool to gain fundamental insights into pectin-cation interactions. These insights can then be used in targeted pectin structural modification, in order to optimize the cation-binding capacity and to promote pectin-cation interactions, for instance for a structure build-up in food products without compromising the mineral nutrition value.

Engineering pectin-based hollow nanocapsules for delivery of anticancer drug

Multifunctional capsules have great applications in biomedical fields. In this study, novel polysaccharide-based nanocapsules were prepared via a layer-by-layer technique using silica as the templates. The shell was constructed based on the electrostatic interactions between pectin and chitosan. The pectin-chitosan nanocapsules ((Pec/Cs)₃Pec) could keep good colloidal stability within 96h in PBS solution and 48h in BSA solution. Meanwhile, the nanocapsules exhibited a high drug loading and pH-sensitive release property for doxorubicin hydrochloride. Moreover, (Pec/Cs)₃Pec nanocapsules had no cytotoxicity to both human hepatocellular carcinoma cells (HepG2 cells) and mouse fibroblast cells (L929 cells). More importantly, (Pec/Cs)₃Pec nanocapsules could be more easily uptaken by HepG2 cells when compared with L929 cells. In vitro anticancer activity tests indicated the carriers could effectively kill HepG2 cells. Overall, (Pec/Cs)₃Pec nanocapsules have great potential as a novel anticancer drug carrier as a result of their pH-sensitivity, good colloidal stability and anticancer activity.

Fluoride loaded polymeric nanoparticles for dental delivery

The overall aim of the present paper was to develop fluoride loaded nanoparticles based on the biopolymers chitosan, pectin, and alginate, for use in dental delivery. First, the preparation of nanoparticles in the presence of sodium fluoride (NaF) as the active ingredient by ionic gelation was investigated followed by an evaluation of their drug entrapment and release properties. Chitosan formed stable, spherical, and monodisperse nanoparticles in the presence of NaF and tripolyphoshate as the crosslinker, whereas alginate and pectin were not able to form any definite nanostructures in similar conditions. The fluoride loading capacity was found to be 33-113ppm, and the entrapment efficiency 3.6-6.2% for chitosan nanoparticles prepared in 0.2-0.4% (w/w) NaF, respectively. A steady increase in the fluoride release was observed for chitosan nanoparticles prepared in 0.2% NaF both in pH5 and 7 until it reached a maximum at time point 4h and maintained at this level for at least 24h. Similar profiles were observed for formulations prepared in 0.4% NaF; however the fluoride was released at a higher level at pH5. The low concentration, but continuous delivery of fluoride from the chitosan nanoparticles, with possible expedited release in acidic environment, makes these formulations highly promising as dental delivery systems in the protection against caries development.

Recent View on Pectin-Based Polysaccharide Nanoscience and Their Biological Applications

Polysaccharide polymer has advantageous applications in bio-field, engineering and food industry because of remarkable properties such as biocompatibility and biodegradability. In this review, we describe the pectin polysaccharide nanomaterials and how the chemistry of pectin works in the development of nanoparticles and nanowires fabrication. We also discussed the recent advances of pectin-based nanomaterials including their synthesis strategies and applications. This pectin nanoscience review can be more useful to gain insight into the pectin nanochemistry for the nanosciences of engineering.

Formulation of polysaccharide-based nanoparticles for local administration into the oral cavity

The efficacy of treatments for oral ailments is often challenged by a low residence time of the conventional pharmaceutical formulations in the oral cavity. The residence time in the oral cavity could be improved by using bioadhesive formulations, such as preparations based on polysaccharides. This study describes the formulation and the evaluation of polysaccharide-based nanosystems as drug delivery systems addressed to the oral cavity. Nanoparticles based on chitosan, alginate or pectin were prepared through self-assembly by ionotropic gelation using oppositely charged crosslinkers (tripolyphosphate or zinc). Characteristics of nanoparticles at increasing crosslinker concentration provided the basis for selecting the most suitable formulations. The nanoparticles were tested for cytotoxicity against buccal cells (TR146) and for stability in a medium simulating pH, ionic strength, electrolyte composition and concentration of saliva. Alginate nanoparticles were the most stable in the salivary environment, while chitosan nanoparticles were the most cytocompatible. Alginate nanoparticles and pectin nanoparticles revealed possible cytotoxicity due to the presence of zinc. This knowledge is important in the early design of polymer-based nanoparticles for oral usage and for potential improving of the biocompatibility of the investigated nanoparticles with the oral environment.

Multivariate analysis for the optimization of polysaccharide-based nanoparticles prepared by self-assembly

Polysaccharide-based nanoparticles are promising carriers for drug delivery applications. The particle size influences the biodistribution of the nanoparticles; hence size distributions and polydispersity index (PDI) are critical characteristics. However, the preparation of stable particles with a low PDI is a challenging task and is usually based on empirical trials. In this study, we report the use of multivariate evaluation to optimize the formulation factors for the preparation of alginate-zinc nanoparticles by ionotropic gelation. The PDI was selected as the response variable. Particle size, size distributions, zeta potential and pH of the samples were also recorded. Two full factorial (mixed-level) designs were analyzed by partial least squares regression (PLS). In the first design, the influence of the polysaccharide and the crosslinker concentrations were studied. The results revealed that size distributions with a low PDI were obtained by using a low polysaccharide concentrations (0.03-0.05%) and a zinc concentration of 0.03% (w/w). However, a high polysaccharide concentration can be advantageous for drug delivery systems. Therefore, in the second design, a high alginate concentration was used (0.09%) and a reduction in the PDI was obtained by simultaneously increasing the ionic strength of the solvent and the zinc concentration. The multivariate analysis also revealed the interaction between the factors in terms of their effects on the PDI; hence, compared to traditional univariate analyses, the multivariate analysis allowed us to obtain a more complete understanding of the effects of the factors scrutinized. In addition, the results are considered useful in order to avoid extensive empirical tests for future formulation studies.

Formulation and preparation of stable cross-linked alginate-zinc nanoparticles in the presence of a monovalent salt

Polysaccharide-based nanoparticles can be formed, under the right conditions, when a counterion is added to a dilute polysaccharide solution. In this study, the possibility of preparing stable alginate nanoparticles cross-linked with zinc was investigated. The effects of the ionic strength of the solvent and the concentration of zinc were studied. The nanoparticles were characterized by dynamic light scattering, zeta potential and pH measurements. The results showed that an increase in the ionic strength of the solvent provided nanoparticles with considerably narrower size distributions compared to pure water, and a small size. The zinc content was shown to be an important factor for the formation of the nanoparticles. In fact, a critical zinc concentration was needed to obtain nanoparticles, and below this concentration particles were not formed. A stepwise increase in the amount of zinc revealed the process of formation of the nanoparticles. The stages of the nanoparticle formation process were identified, and differences according to the ionic strength of the solvent were also reported. Furthermore, the stability test of the most promising formulation showed a stability of over ten weeks.

Structural behaviour differences in low methoxy pectin solutions in the presence of divalent cations (Ca(2+) and Zn(2+)): a process driven by the binding mechanism of the cation with the galacturonate unit

In this paper, we compare the interactions between low methoxy pectin (LMP) and either Ca(2+) or Zn(2+) in semi-dilute solutions. Intrinsic viscosity and turbidity measurements reveal that pectin-calcium solutions are more viscous, but yet less turbid, than pectin-zinc ones. To get a molecular understanding of the origin of this rather unexpected behavior, we further performed isothermal titration calorimetry, small angle neutron scattering experiments, as well as molecular dynamics simulations. Our results suggest that calcium cations induce the formation of a more homogeneous network of pectin than zinc cations do. The molecular dynamics simulations indicate that this difference could originate from the way the two cations bind to the galacturonate unit (Gal), the main component of LMP: zinc interacts with both carboxylate and hydroxyl groups of Gal, in a similar way to that described in the so-called egg-box model, whereas calcium only interacts with carboxylate groups. This different binding behavior seems to arise from the stronger interaction of water molecules with zinc than with calcium. Accordingly, galacturonate chains are more loosely associated with each other in the presence of Ca(2+) than with Zn(2+). This may improve their ability to form a gel, not only by dimerization, but also by the formation of point-like cross-links. Overall, our results show that zinc binds less easily to pectin than calcium does.

Novel polysaccharide nanowires; synthesized from pectin-modified methacrylate

Preparation of nanowires and nanoparticles of water/oil emulsion method using methacrylated pectin (Ma-pectin).

Electrodeposition of gold nanoparticles on a pectin scaffold and its electrocatalytic application in the selective determination of dopamine

Electrodeposition of gold nanoparticles on a pectin scaffold for the selective determination of dopamine.