Polysaccharides in colon-specific drug delivery

Film Coating of Phosphorylated Mandua Starch on Matrix Tablets for pH-Sensitive Release of Mesalamine

Chemically modified mandua starch was successfully synthesized and applied to coat mesalamine-loaded matrix tablets. The coating material was an aqueous dispersion of mandua starch modified by sodium trimetaphosphate and sodium tripolyphosphate. To investigate the colon-targeting release competence, chemically modified mandua starch film-coated mesalamine tablets were produced using the wet granulation method followed by dip coating. The effect of the coating on the colon-targeted release of the resultant delivery system was inspected in healthy human volunteers and rabbits using roentgenography. The results show that drug release was controlled when the coating level was 10% w/w. The release percentage in the upper gastric phase (pH 1.2, simulated gastric fluid) was less than 6% and reached up to 59.51% w/w after 14 h in simulated colonic fluid. In addition to in vivo roentgenographic studies in healthy rabbits, human volunteer studies proved the colon targeting efficiency of the formulation. These results clearly demonstrated that chemically modified mandua starch has high effectiveness as a novel aqueous coating material for controlled release or colon targeting.

Recent updates on guar gum derivatives in colon specific drug delivery

Colon specific delivery of therapeutics have gained much attention of pharmaceutical researchers in the recent past. Colonic specific targeting of drugs is used not only for facilitating absorption of protein or peptide drugs, but also localization of therapeutic agents in colon to treat several colonic disorders. Among various biopolymers, guar gum (GG) exhibits pH dependent swelling, which allows colon specific release of drug. GG also shows microbial degradation in the colonic environment which makes it a suitable excipient for developing colon specific drug delivery systems. The uncontrolled swelling and hydration of GG can be controlled by structural modification or by grafting with another polymeric moiety. Several graft copolymerized guar gum derivatives are investigated for colon targeting of drugs. The efficacy of various guar gum derivatives are evaluated for colon specific delivery of drugs. The reviewed literature evidenced the potentiality of guar gum in localizing drugs in the colonic environment. This review focuses on the synthesis of several guar gum derivatives and their application in developing various colon specific drug delivery systems including matrix tablets, coated formulations, nano or microparticulate delivery systems and hydrogels.

Sensitive delivery systems and novel encapsulation technologies for live biotherapeutic products and probiotics

Live biotherapeutic product (LBP), a type of biological product, holds promise for the prevention or treatment of metabolic disease and pathogenic infection. Probiotics are live microorganisms that improve the intestinal microbial balance and beneficially affect the health of the host when ingested in sufficient numbers. These biological products possess the advantages of inhibition of pathogens, degradation of toxins, and modulation of immunity. The application of LBP and probiotic delivery systems has attracted great interest to researchers. The initial used technologies for LBP and probiotic encapsulation are traditional capsules and microcapsules. However, the stability and targeted delivery capability require further improved. The specific sensitive materials can greatly improve the delivery efficiency of LBPs and probiotics. The specific sensitive delivery systems show advantages over traditional ones due to their better properties of biocompatibility, biodegradability, innocuousness, and stability. Moreover, some new technologies, including layer-by-layer encapsulation, polyelectrolyte complexation, and electrohydrodynamic technology, show great potential in LBP and probiotic delivery. In this review, novel delivery systems and new technologies of LBPs and probiotics were presented, and the challenges and prospects were explored in specific sensitive materials for LBP and probiotic delivery.

Polysaccharide mediated nanodrug delivery: A review

Polysaccharides have drawn a lot of attention due to their potential as carriers for drugs and other bioactive chemicals. In drug delivery systems, natural macromolecules such as polysaccharides are widely utilized as polymers. This utilization extends to various polysaccharides employed in the development of nanoparticles for medicinal administration, with the goal of enhancing therapeutic efficacy while minimizing side effects. This study not only offers an overview of the existing challenges faced by these materials but also provides detailed information on key polysaccharides expertly engineered into nanoparticles. Noteworthy examples include Bael Fruit Gum, Guar Gum, Pectin, Agar, Cellulose, Alginate, Chitin, and Gum Acacia, each selected for their distinctive properties and strategically integrated into nanoparticles. The exploration of these natural macromolecules illuminates their diverse applications and underscores their potential as effective carriers in drug delivery systems. By delving into the unique attributes of each polysaccharide, this review aims to contribute valuable insights to the ongoing advancements in nanomedicine and pharmaceutical technologies. The overarching objective of this review research is to assess the utilization and comprehension of polysaccharides in nanoapplications, further striving to promote their continued integration in contemporary therapeutics and industrial practices.

β-Glycosidase sensitive oral nanoparticles for combined photothermal and chemo treatment of colorectal cancer

Colorectal cancer is one of the most common malignant tumors in the world, and its treatment strategies mainly include surgical resection, chemotherapy, adjuvant radiotherapy, and immunotherapy. Among them, chemotherapy inevitably produces systemic toxicity due to the lack of tumor targeting properties and drug resistance caused by long-term medication frequently occurs, immensely constraining the efficacy of chemotherapy alone. To solve the above-mentioned problems, rhamnolipid was used to encapsulate the chemotherapeutic drug 5-FU and photothermal agent bismuthene nanosheets (BiNS), chitosan was applied as the shell of the nanoparticle, and BiNS@RHL-CS/5-FU NPs for oral administration was successfully prepared. When transported in the stomach and small intestine, the double protection of rhamnolipid and chitosan shell prevented the early release of BiNS and 5-FU. When transported to the colon, β-glycosidase existing in the microenvironment along with elevated pH degraded the chitosan shell, and the reduction in particle size was beneficial for tumor tissue to uptake nanoparticles, thus greatly improving the tumor targeting ability of 5-FU and reducing the systemic toxicity. Due to the presence of BiNS, 1.0 W cm-2 808 nm laser irradiation significantly increased the temperature of the tumor site, not only killing tumor cells directly but also promoting cell uptake and penetration of nanoparticles in the tumor tissue, accelerating the release of 5-FU and improving the sensitivity of tumor cells to chemotherapy, eventually solving the shortcomings of traditional chemotherapy alone. Excellent anti-tumor efficacy has been achieved in both in vitro and in vivo experiments.

Exploring the potential of pH-sensitive polymers in targeted drug delivery

The pH-sensitive polymers have attained significant attention in the arena of targeted drug delivery (TDD) because of their exceptional capability to respond to alteration in pH in various physiological environments. This attribute aids pH-sensitive polymers to act as smart carriers for therapeutic agents, transporting them precisely to target locations while curtailing the release of drugs in off-targeted sites, thereby diminishing side effects. Many pH-responsive polymers in TDD have revealed promising results, with increased therapeutic efficacy and decreased toxic effects. Several pH-sensitive polymers, including, hydroxy-propyl-methyl cellulose, poly (methacrylic acid) (Eudragit series), poly (acrylic acid), and chitosan, have been broadly studied for their myriad applications in the management of various types of diseases. Additionally, the amalgamation of pH-sensitive polymers with, additive manufacturing techniques like 3D printing, has resulted in the progression of novel drug delivery systems that regulate drug release in a controlled manner. Herein, types of pH-sensitive polymers in TDD are systemically reviewed. We have briefly discussed the nanocarriers employed for the delivery of various pH-sensitive polymers in TDD. Finally, miscellaneous applications of pH-sensitive polymers are discussed thoroughly with special attention to the implication of 3D printing in pH-sensitive polymers.

G-POSS connected double network starch gels for protein release

Starch is one of the most frequently preferred natural polymers in hydrogel synthesis. Herein, we combined two strategies of associating brittle and ductile networks in a structure and incorporating inorganic particles into the polymeric gel to design mechanically enhanced nanocomposite double network (DN) starch gels. For the first time in the literature, nanocomposite starch gels (s-NC) were designed by cross-linking starch chains with 8-armed glycidyl-polyhedral oligomeric silsesquioxane (g-POSS) units. Fourier Transform Infrared Spectroscopy and Energy Dispersive X-Ray Spectroscopy analyses have proven that g-POSS is included in the gel structure and is homogeneously distributed throughout the network. More stable d-NC-DMA and d-NC-VP gels were obtained by incorporating N,N-dimethylacrylamide (DMA), or 1-vinyl-2-pyrrolidinone (VP) units, respectively, into g-POSS-linked starch gels, and the reaction kinetics were followed in situ. In SEM images, it was observed that d-NC-DMA had smaller pores and thicker pore walls compared to s-NC and d-NC-VP starch gels, and its mechanical strength was shown to be much superior by rheological tests, compression, and tensile analyses. In addition to increasing the mechanical strength of the gels, the potential of starch in protein release applications using amylase sensitivity has been demonstrated in vitro experiments using the model protein BSA.

Influence of the Encapsulating Agent on the Bioaccessibility of Phenolic Compounds from Microencapsulated Propolis Extract during In Vitro Gastrointestinal Digestion

The aim of this work is to develop different encapsulated propolis ingredients by spray-drying and to evaluate their bioaccessibility using simulated in vitro digestion. To achieve these goals, first, microparticles of a propolis extract with inulin as the coating polymer were prepared under the optimal conditions previously determined. Then, a fraction of inulin was replaced with other encapsulating agents, namely sodium alginate, pectin, and chitosan, to obtain different ingredients with controlled release properties in the gastrointestinal tract. The analysis of the phenolic profile in the propolis extract and microparticles showed 58 compounds tentatively identified, belonging mainly to phenolic acid derivatives and flavonoids. Then, the behavior of the free extract and the formulated microparticles under gastrointestinal conditions was studied through an in vitro gastrointestinal digestion process using the INFOGEST protocol. Digestion of the free extract resulted in the degradation of most compounds, which was minimized in the encapsulated formulations. Thus, all developed microparticles could be promising strategies for improving the stability of this bioactive extract under gastrointestinal conditions, thereby enhancing its beneficial effect.

Characteristics of Interpolyelectrolyte Complexes Based on Different Types of Pectin with Eudragit® EPO as Novel Carriers for Colon-Specific Drug Delivery

Given that pectin is a well-known substance used for drug delivery, we aimed to obtain and further examine the efficacy of interpolyelectrolyte complexes based on citrus or apple pectin and the Eudragit® EPO for using these carriers in oral drug delivery. To characterize the physicochemical properties of these compounds, turbidity, gravimetry, viscosity, elementary analysis, FTIR spectroscopy, and DSC analysis were utilized. Diffusion transport characteristics were evaluated to assess the swelling ability of the matrices and the release of diclofenac sodium. To examine the release parameters, mathematical modeling was performed by using the Korsmayer-Peppas and Logistic equations as well. During the turbidity study, stoichiometry compositions were selected for the developed IPECs EPO/PecA and EPO/PecC at pH values = 4.0, 5.0, 6.0, and 7.0. The FTIR spectra of the complexes were characterized by an increase in the intensity of the bands at 1610 cm-1 and 1400 cm-1. According to the DSC analysis, IPEC has a certain Tg = 57.3 °C. The highest release rates were obtained for IPEC EPO/PecC_1 and EPO/PecC_4. The mechanism of drug transport from the matrices IPEC EPO/PecC, IPEC EPO/PecA_3, and EPO/PecA_4 can be characterized as Super Case II. Anomalous release (non-Fickian release) is typical for IPEC EPO/PecA_1 and EPO/PecA_2. Thus, the resulting systems can be further used for the effective delivery of the drugs to the colon.

Aerogels as Carriers for Oral Administration of Drugs: An Approach towards Colonic Delivery

Polysaccharide aerogels have emerged as a highly promising technology in the field of oral drug delivery. These nanoporous, ultralight materials, derived from natural polysaccharides such as cellulose, starch, or chitin, have significant potential in colonic drug delivery due to their unique properties. The particular degradability of polysaccharide-based materials by the colonic microbiota makes them attractive to produce systems to load, protect, and release drugs in a controlled manner, with the capability to precisely target the colon. This would allow the local treatment of gastrointestinal pathologies such as colon cancer or inflammatory bowel diseases. Despite their great potential, these applications of polysaccharide aerogels have not been widely explored. This review aims to consolidate the available knowledge on the use of polysaccharides for oral drug delivery and their performance, the production methods for polysaccharide-based aerogels, the drug loading possibilities, and the capacity of these nanostructured systems to target colonic regions.

Design and development of pH-responsive alginate-based nanogel carriers for etoposide delivery

Recently, pH-responsive nanogels are playing progressively important roles in cancer treatment. The present study focuses on designing and developing pH-responsive alginate-based nanogels to achieve a controlled release of etoposide (Et) while enhancing its hydrophilicity. Alginate (ALG) is grafted with 2-hydroxypropyl methacrylamide (HPMA) through a microwave-supported method, and the chemical structure of the graft copolymer (ALG-g-PHPMA) was verified by 1H/13C NMR and FTIR techniques. The ALG-g-PHPMA and anticancer drug-loaded ALG-g-PHPMA@Et nanogels were obtained using an emulsion method, and their structures were characterized through FTIR, TG/DSC, AFM/TEM, BET, and DLS analyses. The ALG-g-PHPMA nanogels demonstrated a good drug encapsulation efficiency (79.60 %), displaying a pH-dependent release profile and an in vitro accelerated release of Et compared to the ALG nanogels. Thermal and BET analyses revealed enhanced stability, surface area, and porosity volume of the alginate nanogels. The grafting of PHPMA chains onto alginate altered the surface topology of the ALG nanogels, resulting in lower surface roughness. Furthermore, cytotoxicity tests showed the high biocompatibility of the ALG-g-PHPMA copolymer and its nanogels. The ALG-g-PHPMA@Et nanogels exhibited a higher anticancer effect on lung cancer (H1299) cells than free etoposide. These results suggest that the ALG-g-PHPMA nanogels can be applied as a pH-dependent nanoplatform for delivering anticancer drugs.

Protein-polysaccharide-based delivery systems for enhancing the bioavailability of curcumin: A review

In recent years, a wide attention has been paid to curcumin in medicine due to its excellent physiological activities, including anti-inflammatory, antioxidant, antibacterial, and nerve damage repair. However, the low solubility, poor stability, and rapid metabolism of curcumin make its bioavailability low, which affects its development and application. As a unique biopolymer structure, protein-polysaccharide (PRO-POL)-based delivery system has the advantages of low toxicity, biocompatibility, biodegradability, and delayed release. Many scholars have investigated PRO-POL -based delivery systems to improve the bioavailability of curcumin. In this paper, we focus on the interactions between different proteins (e.g. casein, whey protein, soybean protein isolate, pea protein, zein, etc.) and polysaccharides (chitosan, sodium alginate, hyaluronic acid, pectin, etc.) and their effects on complexes diameter, surface charge, encapsulation drive, and release characteristics. The mechanism of the PRO-POL-based delivery system to enhance the bioavailability of curcumin is highlighted. In addition, the application of PRO-POL complexes loaded with curcumin is summarized, aiming to provide a reference for the construction and application of PRO-POL delivery systems.

pH stimuli-responsive hydrogels from non-cellulosic biopolymers for drug delivery

Over the past several decades, there has been significant growth in the design and development of more efficient and advanced biomaterials based on non-cellulosic biological macromolecules. In this context, hydrogels based on stimuli-responsive non-cellulosic biological macromolecules have garnered significant attention because of their intrinsic physicochemical properties, biological characteristics, and sustainability. Due to their capacity to adapt to physiological pHs with rapid and reversible changes, several researchers have investigated pH-responsive-based non-cellulosic polymers from various materials. pH-responsive hydrogels release therapeutic substances in response to pH changes, providing tailored administration, fewer side effects, and improved treatment efficacy while reducing tissue damage. Because of these qualities, they have been shown to be useful in a wide variety of applications, including the administration of chemotherapeutic drugs, biological material, and natural components. The pH-sensitive biopolymers that are utilized most frequently include chitosan, alginate, hyaluronic acid, guar gum, and dextran. In this review article, the emphasis is placed on pH stimuli-responsive materials that are based on biological macromolecules for the purposes of drug administration.

New insights on the effects of blend composition on the biodegradation and permeability of Inulin-Eudragit RS film coatings for colon drug delivery

Inulin has been applied in Inulin-Eudragit RS (Inu-ERS) coatings as the component responsible for degradation by human microbiota. However, studies on how bacterial enzymes can degrade polysaccharides like inulin imbedded in water insoluble polymers like Eudragit RS are still elusive. The present work aims at elucidating the complex process of enzyme triggered biodegradation of inulin with various molecular weights in isolated films with Eudragit RS. The ratio of inulin to Eudragit RS was varied to create films with different degree of hydrophilicity. The phase behavior study revealed that blends of inulin and Eudragit RS are phase separated systems. The film permeability was studied by determination of the permeability coefficient of caffeine and the fraction of inulin that was released from the films in a buffer solution with or without inulinase was quantified. Together with the morphology characterization of the Inu-ERS films with and without incubation in the enzyme solution, these results suggest that the action of the enzyme was only limited to the fraction of inulin released in the buffer solution. Inulin fully embedded in the Eudragit RS matrix was not degraded. The permeation of the model drug caffeine occurred in the phase-separated film as a result of pores formed as a consequence of inulin release. The inulin to Eudragit RS blend ratio and the molecular weight of inulin affected the percolation threshold, the release of inulin, the morphology of the film formed thereafter and the connectivity of the formed water channels, thus influencing the drug permeation properties.

Oral insulin delivery: Barriers, strategies, and formulation approaches: A comprehensive review

Diabetes Mellitus is characterized by a hyperglycemic condition which can either be caused by the destruction of the beta cells or by the resistance developed against insulin in the cells. Insulin is a peptide hormone that regulates the metabolism of carbohydrates, proteins, and fats. Type 1 Diabetes Mellitus needs the use of Insulin for efficient management. However invasive methods of administration may lead to reduced adherence by the patients. Hence there is a need for a non-invasive method of administration. Oral Insulin has several merits over the conventional method including patient compliance, and reduced cost, and it also mimics endogenous insulin and hence reaches the liver by the portal vein at a higher concentration and thereby showing improved efficiency. However oral Insulin must pass through several barriers in the gastrointestinal tract. Some strategies that could be utilized to bypass these barriers include the use of permeation enhancers, absorption enhancers, use of suitable polymers, use of suitable carriers, and other agents. Several formulation types have been explored for the oral delivery of Insulin like hydrogels, capsules, tablets, and patches which have been described briefly by the article. A lot of attempts have been made for developing oral insulin delivery however none of them have been commercialized due to numerous shortcomings. Currently, there are several formulations from the companies that are still in the clinical phase, the success or failure of some is yet to be seen in the future.

Beyond cellulose: pharmaceutical potential for bioactive plant polysaccharides in treating disease and gut dysbiosis

Polysaccharides derived from plants, algae, or fungi serve as the major components of some human diets. Polysaccharides have been shown to exhibit diverse biological activities in improving human health, and have also been proposed to function as potent modulators of gut microbiota composition, thus playing a bi-directional regulatory role in host health. Here, we review a variety of polysaccharide structures potentially linked to biological functions, and cover current research progress in characterizing their pharmaceutical effects in various disease models, including antioxidant, anticoagulant, anti-inflammatory, immunomodulatory, hypoglycemic, and antimicrobial activities. We also highlight the effects of polysaccharides on modulating gut microbiota via enrichment for beneficial taxa and suppression of potential pathogens, leading to increased microbial expression of carbohydrate-active enzymes and enhanced short chain fatty acid production. This review also discusses polysaccharide-mediated improvements in gut function by influencing interleukin and hormone secretion in host intestinal epithelial cells.

Conception of Cellulose/Alginate/Mesalazine microspheres by solvent evaporation technique for drug release: Experimental and theoretical investigations

Preparation of microspheres containing Mesalazine referred to as 5-aminosalicylic acid (5-ASA) for colon targeting drug was carried out using the emulsion solvent evaporation technique. The formulation was based on 5-ASA as the active agent, sodium Alginate (SA) andEthylcellulose (EC) as encapsulating agents, with polyvinyl alcohol (PVA) as emulsifier. The effects ofthe following processing parameters, 5-ASA %, EC:SA ratio and stirring rate on the properties of the resulting products in the form microspheres were considered. The samples were characterized using Optical microscopy, SEM, PXRD, FTIR, TGA, and DTG. In vitro release of 5-ASA from the different batches of microspheres was tested in biologically simulated fluids, (gastric; SGF, pH 1.2 for 2 h), then (intestinal fluid SIF, pH 7.4for 12 h) at 37 °C. The release kinetic results have been treated mathematically relaying on Higuchi's and Korsmeyer-Peppas' models for drug liberation. DOE study was performed to evaluate the interactive effects of variables on the drug entrapment and microparticle sizes. Molecular chemical interactions in structures were optimized using DFT analysis.

Crosslinked and PEGylated Pectin Chitosan Nanoparticles for Delivery of Phytic Acid to Colon

Polysaccharide-based nanoparticles (NPs) such as pectin/ chitosan (PN/CN) had always been of greatest interest because of their excellent solubility, biocompatibility, and higher suitability for oral drug delivery. This study employed blending-crosslinking of polymers (PN&CN) followed by emulsification-solvent evaporation to prepare and compare two sets of PEGylated NPs to deliver phytic acid (IP6) to colon orally as it has potential to manage colon cancer but fails to reach colon when ingested in pure form. The first set was crosslinked with Glutaraldehyde (GE) (GE*PN-CN-NPs) while the second set was crosslinked with sodium tripolyphosphate (TPP) (TPP*PN-CN-NPs). IP6-loaded-GE/TPP*PN-CN-NPs were optimized using a central composite design. Developed TPP*PN-CN-NPs had a smaller size (210.6±7.93nm) than GE*PN-CN-NPs (557.2±5.027nm). Prepared NPs showed <12% IP6 release at pH 1.2 whereas >80% release was observed at pH 7.4. Further, NPs were explored for cytocompatibility in J774.2 cell lines, cytotoxicity, and cellular uptake in HT-29 and DLD-1 cell lines. While exhibiting substantial cytotoxicity and cellular uptake in HT-29 and DLD-1, the NPs were deemedsafe in J774.2. The PEGylated-TPP*PN-CN-NPs showed time-dependent uptake in J774.2 cell lines. Conclusively, the employed NP development method successfully delivered IP6 to colon and may also open avenues for the oral delivery of other drugs to colon.

Green Chemistry Principles for Nano- and Micro-Sized Hydrogel Synthesis

The growing demand for drug carriers and green-technology-based tissue engineering materials has enabled the fabrication of different types of micro- and nano-assemblies. Hydrogels are a type of material that have been extensively investigated in recent decades. Their physical and chemical properties, such as hydrophilicity, resemblance to living systems, swelling ability and modifiability, make them suitable to be exploited for many pharmaceutical and bioengineering applications. This review deals with a brief account of green-manufactured hydrogels, their characteristics, preparations, importance in the field of green biomedical technology and their future perspectives. Only hydrogels based on biopolymers, and primarily on polysaccharides, are considered. Particular attention is given to the processes of extracting such biopolymers from natural sources and the various emerging problems for their processing, such as solubility. Hydrogels are catalogued according to the main biopolymer on which they are based and, for each type, the chemical reactions and the processes that enable their assembly are identified. The economic and environmental sustainability of these processes are commented on. The possibility of large-scale processing in the production of the investigated hydrogels are framed in the context of an economy aimed at waste reduction and resource recycling.

Potential role of plant polysaccharides as immunostimulants in aquaculture: a review

Aquaculture is one of the primary food-producing sectors in the world that ensures human nourishment. However, aqua farmers are facing serious problems due to disease out breaks and development of antimicrobial resistance. Until now, chemical or antibiotic based strategies has been applied to control disease related concern in aquaculture. Frequent usage of antibiotics in feed or usage of disinfectant to overcome the disease may end up with negative impacts to the environment and human. Utilization of plant derived polysaccharides has been drastically increased due to their effective roles and could serve as a best replacement for chemical agents and antibiotics. In addition, plant derived compounds and plant extracts was utilized to improve the immunity, intestinal health and growth performance of aquaculturable organisms. In addition, large number of plant-based polysaccharides was utilized as immunostimulants in aquaculture. Hence, this review aims to highlight the multifunctional properties of plant-based polysaccharides in aquaculture. Moreover, advantages and different concentration of plant polysaccharides as a feed additives in aquaculture sector has been discussed herein.

Advances in Polysaccharide-Based Oral Colon-Targeted Delivery Systems: The Journey So Far and the Road Ahead

Various colon-targeted oral delivery systems have been explored so far to treat colorectal diseases, including timed-release systems, prodrugs, pH-based polymer coatings, and microflora-triggered systems. Among them, the microbially triggered system has gained attention. Among various oral colon-targeted delivery systems discussed, the polysaccharide-based colon-targeted delivery system has been found to be quite promising as polysaccharides remain unaffected by gastric as well as upper intestine milieu and are only digested by colonic bacteria upon reaching the colon. The major bottleneck associated with this delivery is that non-suitability of this system during the diseased state due to decrease in bacterial count at that time. This causes the failure of delivery system to release the drug even at colonic site as the polysaccharide matrix/coat cannot be digested properly due to lack of bacteria. The co-administration of probiotics is reported to compensate for the bacterial loss besides facilitating site-specific release. However, this research is also limited at the preclinical level. Hence, efforts are required to make this technology scalable and clinically applicable. This article entails in detail various oral colon-targeted delivery systems prepared so far, as well as the limitations and benefits of polysaccharide-based oral colon-targeted delivery systems.

Recent advances on nanoparticle-based therapies for cardiovascular diseases

Nanoparticles are exclusively suitable for studying and developing potential therapies against cardiovascular diseases (CVD) because of their size, fine-tunable properties, and ability to incorporate therapeutic and imaging modalities. Recent advancements in nanomaterials open new avenues for treating CVD. In cardiology, the use of nanoparticles and nanocarriers has gathered significant consideration owing to characteristic features such as active and passive targeting to the cardiac tissues, greater target specificity, and sensitivity. It has been reported that through the use of nanotechnology, more than 50% of CVDs can be treated efficiently. Heart-targeted nano carrier-based drug delivery is an effective and efficient approach for treating cardiac-related disorders such as atherosclerosis, hypertension, and myocardial infarction. In this review, the authors focus on nanoparticle-based therapies used in CVD and provide an outline of essential knowledge and critical concerns on polymer-based nanomaterials in treating CVD.

Commercially Available Enteric Empty Hard Capsules, Production Technology and Application

Currently, there is a growing need to prepare small batches of enteric capsules for individual therapy or clinical evaluation since many acidic-sensitive substances should be protected from the stomach's acidic environment, including probiotics or fecal material, in the fecal microbiota transplantation (FMT) process. A suitable method seems to be the encapsulation of drugs or lyophilized alternatively frozen biological suspensions in commercial hard enteric capsules prepared by so-called Enteric Capsule Drug Delivery Technology (ECDDT). Manufacturers supply these types of capsules, made from pH-soluble polymers, in products such as AR Caps®, EnTRinsicTM, and Vcaps® Enteric, or capsules made of gelling polymers that release their content as the gel erodes over time when passing through the digestive tract. These include DRcaps®, EMBO CAPS® AP, BioVXR®, or ACGcaps™ HD. Although not all capsules in all formulations meet pharmaceutical requirements for delayed-release dosage forms in disintegration and dissolution tests, they usually find practical application. This literature review presents their composition and properties. Since ECDDT is a new technology, this article is based on a limited number of references.

Carbohydrate Polymer-Based Targeted Pharmaceutical Formulations for Colorectal Cancer: Systematic Review of the Literature

Colon cancer is the third most diagnosed cancer worldwide, followed by lung and breast cancer. Conventional treatment methods are associated with numerous side effects and compliance issues. Thus, colon targeted drug delivery has gained much attention due to its evident advantages. Although many technologies have been explored, the use of pH-sensitive polymers, especially biodegradable polymers, holds exceptional promise. This review aims to collate research articles concerning recent advances in this area. A systematic search using multiple databases (Google Scholar, EMBASE, PubMed, MEDLINE and Scopus) was carried out following the preferred reported items for systematic reviews and meta-analyses (PRISMA) guidelines with an aim to explore the use of pH-sensitive carbohydrate polymers in developing colon targeted pharmaceutical formulations. Following screening and quality assessment for eligibility, 42 studies were included, exploring either single or a combination of carbohydrate polymers to develop targeted formulations for colon cancer therapy. Pectin (11) is the most widely used of these biopolymers, followed by chitosan (09), alginate (09) and guar gum (08). This systematic review has successfully gathered experimental evidence highlighting the importance of employing carbohydrate polymers in developing targeting formulations to manage colon cancer.

Microfluidized Dextran Microgels Loaded with Cisplatin/SPION Lipid Nanotherapeutics for Local Colon Cancer Treatment via Oral Administration

Multifunctional sequential targeted delivery system is developed as an efficient therapeutic strategy against malignant tumors with selective accumulation and minimal systemic drug absorption. The therapeutic system is comprised of microfluidized dextran microgels encapsulating cisplatin/superparamagnetic iron oxide nanoparticles (SPIONs)-loaded trilaurin-based lipid nanoparticles (LNPs). The microgel system is imparted hierarchically dual targeting via dextran and folic acid (FA) residues, leading to increases both in retention of the microgels in colon and in cellular uptake of the therapeutic LNPs by colon cancer cells while being used for oral therapeutic delivery. Encapsulation of the therapeutic LNPs into dextran microgels attained by microfluidized crosslinking reaction reduces gastrointestinal adhesion and prevents the FA-modified LNPs from cellular transport by proton-coupled FA transporters in small intestine during their oral delivery to colon. Upon enzymatic degradation of the dextran microgels by dextranase present exclusively in colon, LNPs thus released become more recognizable and readily internalized by FA receptor-overexpressing colon cancer cells. The combined chemo/magnetothermal therapeutic effect of dual targeted lipid nanoparticle-loaded microgels from entrapped lipidized cisplatin and alternating magnetic field-treated SPIONs significantly inhibits tumor growth and suppresses metastatic peritoneal carcinomatosis in orthotopic colon cancer-bearing mice.

Delivery system for grape seed extract based on biodegradable pectin-Zn-alginate gel particles

Pectin-Zn-alginate gel particles from callus culture pectin with increased linearity and decreased rhamnogalacturonan I branching and degree of methylesterification had a higher gel strength and encapsulation capacity. An increase of the alginate concentration led to an increase in the particle gel strength. The grape seed extract (GSE) loaded and empty particles swelled slightly in the simulated gastric fluid (SGF) and gradually in the intestinal (SIF) fluid. The swelling degrees of the GSE-loaded and empty particles in the simulated colonic fluids (SCF) were decreased in the range SCF-7.0 (pH 7.0 + pectinase) > SCF-5.3 (pH 5.3 + pectinase) > SCF-2.3 (pH 2.3 + pectinase). The FTIR spectra indicated that GSE was embedded in the composite particles. Negligible leakage of GSE in SGF was shown. The increase in GSE release in SIF was due to the decrease in particle gel strength and increased swelling degree. The GSE release in fluids simulating the colon inflammation (SCF-2.3 and SCF-5.3) was similar, and it was lower than that in the SCF-7.0 simulating a healthy colon due to the increased gel strength. The percentage release of GSE increased slightly after exposure to different pH. Pectin-Zn-alginate hydrogel systems may be promising candidates for colon-targeted GSE delivery systems.

Core-shell polygalacturonate magnetic iron oxide nanoparticles: Synthesis, characterization, and functionalities

This work aims to synthesize polygalacturonate-based magnetic iron oxide nanoparticles (INP-polyGalA). The synthesis consists of the diffusion of both Fe²⁺ and Fe³⁺ at a molar ratio of 1:2 through polyGalA solution followed by the addition of an alkaline solution. To form individual nanoparticle materials, the polyGalA concentration needs to be below its overlapping concentration (C*). The synthesized materials (INP-polyGalA) contain about 45 % of organic compound (polyGalA), and they have an average particle size ranging from 10 to 50 nm as estimated by several techniques (DLS, TEM and AFM) and their surfaces are negatively charged in pH range 2 to 7. The synthesized NPs showed magnetic characteristics, thanks to the formation of magnetite (Fe₃O₄) as confirmed by X-ray diffractions (XRD). Moreover, AFM combined with Infra-red mapping allowed us to conclude that polyGalA is located in the core of the nanoparticles but also on their surfaces. More specially, both carboxylate (COO^-) and carboxylic (COOH) groups of polyGalA are observed on the NPs surfaces. The presence of such functional groups allowed the synthesized material to (i) bind through the electrostatic interactions methylene blue (MB) which may have a great potential for r pollution control or (ii) to form hydrogel beads (ionotropic gelation) by using calcium as a crosslinking agent which can be used to encapsulate active molecules and target their release by using an external stimulus (magnetic field).

Synthesis and characterization of photo-crosslinkable cinnamate-functionalized pectin

The polysaccharide pectin (PC) was functionalized with the photo-responsive cinnamic acid hydrazide (CN) to produce the photo-crosslinkable PC-CN hydrogel material that was then evaluated as a carrier for encapsulation of the drug model aspirin. Cinnamic acid hydrazide was first prepared and then incorporated with the abundant -COOCH₃ groups on the pectin chain via hydrazide linkage. The obtained polymeric derivatives have been characterized by means of instrumental techniques including FTIR and NMR. The obtained PC-CN hydrogels with different cinnamic functionality were also freeze-dried and examined by SEM, which indicated more coherent hydrogel texture by increasing the cinnamic functionalization. The effect of the photo-curing time, as well as the functionalization degree, on the swelling and gelation of the obtained hydrogel was also studied to evaluate the potential of the developed material in drug delivery systems using aspirin as a common and available drug model. The developed PC-CN hydrogel materials exhibited high potential as a drug carrier that enables the control of the drug release via optimizing both the degree of cinnamic functionality and the photo-curing time.

A Synthetic Gene Library Yields a Previously Unknown Glycoside Phosphorylase That Degrades and Assembles Poly-β-1,3-GlcNAc, Completing the Suite of β-Linked GlcNAc Polysaccharides

The considerable utility of glycoside phosphorylases (GPs) has led to substantial efforts over the past two decades to expand the breadth of known GP activities. Driven largely by the increase of available genomic DNA sequence data, the gap between the number of sequences in the carbohydrate active enzyme database (CAZy DB) and its functionally characterized members continues to grow. This wealth of sequence data presented an exciting opportunity to explore the ever-expanding CAZy DB to discover new GPs with never-before-described functionalities. Utilizing an in silico sequence analysis of CAZy family GH94, we discovered and then functionally and structurally characterized the new GP β-1,3-N-acetylglucosaminide phosphorylase. This new GP was sourced from the genome of the cell-wall-less Mollicute bacterium, Acholeplasma laidlawii and was found to synthesize β-1,3-linked N-acetylglucosaminide linkages. The resulting poly-β-1,3-N-acetylglucosamine represents a new, previously undescribed biopolymer that completes the set of possible β-linked GlcNAc homopolysaccharides together with chitin (β-1,4) and PNAG (poly-β-1,6-N-acetylglucosamine). The new biopolymer was denoted acholetin, a combination of the genus Acholeplasma and the polysaccharide chitin, and the new GP was thus denoted acholetin phosphorylase (AchP). Use of the reverse phosphorolysis action of AchP provides an efficient method to enzymatically synthesize acholetin, which is a new biodegradable polymeric material.

Biomedical applications of polysaccharide nanoparticles for chronic inflammatory disorders: Focus on rheumatoid arthritis, diabetes and organ fibrosis

Polysaccharides are biopolymers distinguished by their complex secondary structures executing various roles in microorganisms, plants, and animals. They are made up of long monomers of similar type or as a combination of other monomeric chains. Polysaccharides are considered superior as compared to other polymers due to their diversity in charge and size, biodegradability, abundance, bio-compatibility, and less toxicity. These natural polymers are widely used in designing of nanoparticles (NPs) which possess wide applications in therapeutics, diagnostics, delivery and protection of bioactive compounds or drugs. The side chain reactive groups of polysaccharides are advantageous for functionalization with nanoparticle-based conjugates or therapeutic agents such as small molecules, proteins, peptides and nucleic acids. Polysaccharide NPs show excellent pharmacokinetic and drug delivery properties, facilitate improved oral absorption, control the release of drugs, increases in vivo retention capability, targeted delivery, and exert synergistic effects. This review updates the usage of polysaccharides based NPs particularly cellulose, chitosan, hyaluronic acid, alginate, dextran, starch, cyclodextrins, pullulan, and their combinations with promising applications in diabetes, organ fibrosis and arthritis.

Targeted delivery of capecitabine to colon cancer cells using nano polymeric micelles based on beta cyclodextrin

Nano polymeric micelles (nano PMs) help to increase accessibility to tumor sites, decrease side effects and allow controlled drug dissemination over a long period of time. The aim of this study was to optimize the delivery of the anticancer drug capecitabine (CAP) using nano PMs and cyclodextrin (CD) to allow the treatment of colon cancer. A pH-responsive copolymer was prepared and the variables of loading time, loading temperature, the amount of copolymer and also the ratio of acrylic/maleic copolymer to beta CD and the effect that these variables have on drug loading were investigated, with variable optimization studies carried out following a definitive screening design (DSD). The morphology and structure of the particles were determined by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy. In vitro drug release exemplified that the micelles were pH-sensitive, this action was shown that firstly the drug release was done perfectly targeted and under control and secondly the drug has been released above 80% inside the colon.

Nano polymeric micelles (nano PMs) help to increase accessibility to tumor sites, decrease side effects and allow controlled drug dissemination over a long period of time.

Clinical translation of advanced colonic drug delivery technologies

Targeted drug delivery to the colon offers a myriad of benefits, including treatment of local diseases, direct access to unique therapeutic targets and the potential for increasing systemic drug bioavailability and efficacy. Although a range of traditional colonic delivery technologies are available, these systems exhibit inconsistent drug release due to physiological variability between and within individuals, which may be further exacerbated by underlying disease states. In recent years, significant translational and commercial advances have been made with the introduction of new technologies that incorporate independent multi-stimuli release mechanisms (pH and/or microbiota-dependent release). Harnessing these advanced technologies offers new possibilities for drug delivery via the colon, including the delivery of biopharmaceuticals, vaccines, nutrients, and microbiome therapeutics for the treatment of both local and systemic diseases. This review details the latest advances in colonic drug delivery, with an emphasis on emerging therapeutic opportunities and clinical technology translation.

In Vitro Methodologies for Evaluating Colon-Targeted Pharmaceutical Products and Industry Perspectives for Their Applications

Several locally acting colon-targeted products to treat colonic diseases have been recently developed and marketed, taking advantage of gastrointestinal physiology to target delivery. Main mechanisms involve pH-dependent, time-controlled and/or enzymatic-triggered release. With site of action located before systemic circulation and troublesome colonic sampling, there is room for the introduction of meaningful in vitro methods for development, quality control (QC) and regulatory applications of these formulations. A one-size-fits-all method seems unrealistic, as the selection of experimental conditions should resemble the physiological features exploited to trigger the release. This article reviews the state of the art for bio-predictive dissolution testing of colon-targeted products. Compendial methods overlook physiological aspects, such as buffer molarity and fluid composition. These are critical for pH-dependent products and time-controlled systems containing ionizable drugs. Moreover, meaningful methods for enzymatic-triggered products including either bacteria or enzymes are completely ignored by pharmacopeias. Bio-predictive testing may accelerate the development of successful products, although this may require complex methodologies. However, for high-throughput routine testing (e.g., QC), simplified methods can be used where balance is struck between simplicity, robustness and transferability on one side and bio-predictivity on the other. Ultimately, bio-predictive methods can occupy a special niche in terms of supplementing plasma concentration data for regulatory approval.

Comparison between the Biological Active Compounds in Plants with Adaptogenic Properties (Rhaponticum carthamoides, Lepidium meyenii, Eleutherococcus senticosus and Panax ginseng)

BACKGROUND

In the 1960s, research into plant adaptogens began. Plants with adaptogenic properties have rich phytochemical compositions and have been used by humanity since ancient times. However, it is not still clear whether the adaptogenic properties are because of specific compounds or because of the whole plant extracts. The aim of this review is to compare the bioactive compounds in the different parts of these plants.

METHODS

The search strategy was based on studies related to the isolation of bioactive compounds from Rhaponticum carthamoides, Lepidium meyenii, Eleutherococcus senticosus, and Panax ginseng. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed.

RESULTS

This review includes data from 259 articles. The phytochemicals isolated from Rhaponticum carthamoides, Lepidium meyenii, Eleutherococcus senticosus, and Panax ginseng were described and classified in several categories.

CONCLUSIONS

Plant species have always played an important role in drug discovery because their effectiveness is based on the hundreds of years of experience with folk medicine in different nations. In our view, there is great potential in the near future for some of the phytochemicals found in these plants species to become pharmaceutical agents.

Exploiting the Metabolism of the Gut Microbiome as a Vehicle for Targeted Drug Delivery to the Colon

The prevalence of colon-associated diseases has increased significantly over the past several decades, as evidenced by accumulated literature on conditions such as Crohn’s disease, irritable bowel syndrome, colorectal cancer, and ulcerative colitis. Developing therapeutics for these diseases is challenging due to physiological barriers of the colon, systemic side effects, and the intestinal environment. Therefore, in a search for novel methods to overcome some of these problems, researchers discovered that microbial metabolism by gut microbiotia offers a potential method for targeted drug delivery This overview highlights several drug delivery systems used to modulate the microbiota and improve colon-targeted drug delivery. This technology will be important in developing a new generation of therapies which harness the metabolism of the human gut microflora.

Role and Merits of Green Based Nanocarriers in Cancer Treatment

Simple Summary

The use of chemotherapy drugs against tumours is associated with various drawbacks such as poor solubility, low stability, high toxicity, lack of selectivity and rapid clearance. Nanocarriers can improve the safety and efficiency of drugs by increasing their solubility, enhance their circulation time and improve their uptake into cancer cells. Natural materials can be incorporated in the fabrication of nanocarriers as a substitute to synthetic ingredients. Several studies developed different types of green based nanocarriers using materials obtained from plant or microbial sources such as polysaccharides and polyphenols without the need of toxic chemicals in the synthesis. The green components can have many roles for example as mechanical support, trigger pH response for drug release, or act as a targeting ligand. The inclusion of these green components will support the cost effective and feasible large-scale production of nanocarriers with minimum negative impact on the environment.

Abstract

The use of nanocarriers for biomedical applications has been gaining interests from researchers worldwide for the delivery of therapeutics in a controlled manner. These “smart” vehicles enhance the dissolution and the bioavailability of drugs and enable their delivery to the target site. Taking the potential toxicity into consideration, the incorporation of natural “green” materials, derived from plants or microbial sources, in the nanocarriers fabrication, improve their safety and biocompatibility. These green components can be used as a mechanical platform or as targeting ligand for the payload or can play a role in the synthesis of nanoparticles. Several studies reported the use of green based nanocarriers for the treatment of diseases such as cancer. This review article provides a critical analysis of the different types of green nanocarriers and their synthesis mechanisms, characterization, and their role in improving drug delivery of anticancer drugs to achieve precision cancer treatment. Current evidence suggests that green-based nanocarriers can constitute an effective treatment against cancer.

Bacteria-Based Microdevices for the Oral Delivery of Macromolecules

The oral delivery of macromolecules is quite challenging due to environmental insults and biological barriers encountered along the gastrointestinal (GI) tract. Benefiting from their living characteristics, diverse bacterial species have been engineered as intelligent platforms to deliver various therapeutics. To tackle difficulties in oral delivery, innovative bacteria-based microdevices have been developed by virtue of advancements in synthetic biology and nanotechnology, with aims to overcome the instability and short half-life of macromolecules in the GI tract. In this review, we summarize the main classes of macromolecules that are produced and delivered through the oral ingestion of bacteria and bacterial derivatives. Furtherly, we discuss the engineering strategies and biomedical applications of these living microdevices in disease diagnosis, bioimaging, and treatment. Finally, we highlight the advantages as well as the limitations of these engineered bacteria used as platforms for the oral delivery of macromolecules and also propose their potential for clinical translation. The results summarized in this review article would contribute to the invention of next-generation bacteria-based systems for the oral delivery of macromolecules.

Challenges and Opportunities of Nanotechnological based Approach for the Treatment of Tuberculosis

Mycobacterium tuberculosis, because of its unique biochemical behavior and a complex host relationship, successfully evades the host immune system. Therefore, chemotherapy appears to be the first-line option for patients with tuberculosis. However, poor patient compliance with anti-tubercular treatment and variability in anti-tubercular drug pharmacokinetics are among the major driving factors for the emergence of drug resistance. The rising cases of extrapulmonary TB, cross-resistance patterns, high prevalence of tuberculosis and HIV co-infections make tuberculosis treatment more complicated than conventional multidrug therapy. Due to their distinct advantages like higher solubility, increased payload, controlled release profiles, tissue-specific accumulation, and lack of toxicity, nanoscale materials have immense potential for drug delivery applications. An appropriate selection of polymer and careful particle engineering further improves therapeutic outcomes with opportunities to overcome conventional anti-tubercular drugs' challenges. The present review introduces the prospect of using nanotechnology in tuberculosis (TB) chemotherapy and provides a comprehensive overview of recent advances in nanocarriers implied for delivering anti-tubercular drugs.

Fabrication, Evaluation, In Vivo Pharmacokinetic and Toxicological Analysis of pH-Sensitive Eudragit S-100-Coated Hydrogel Beads: a Promising Strategy for Colon Targeting

The aim of present research aims to fabricate a system of enteric coating of hydrogel beads with pH-sensitive polymer, which shows solubility at pH > 7, and explore their potential to target the colon for drug delivery. Hydrogel beads were fabricated through the extrusion-dripping technique followed by ion gelation crosslinking. Moreover, freeze-thaw cycle was implemented for crosslinking of polyvinyl alcohol (PVA)/Ca-alginate blend beads. The oil-in-oil solvent evaporation method was adopted for the Eudragit coating of hydrogel beads using different coat: core ratios (4:1 or 8:1). Coated and uncoated hydrogel beads were evaluated by in vitro physicochemical properties, swelling and drug release behaviours, and in vivo pharmacokinetics, swelling, and toxicity evaluation. Diclofenac sodium was loaded as an experimental drug. Drug entrapment efficiency for the PVA/Ca-alginate beads was calculated as 98%, and for Ca-alginate beads, it came out to a maximum of 74%. Drug release study at various pH suggested that, unlike uncoated hydrogel beads, the coated beads delay the release of diclofenac sodium in low pH of the gastric and intestinal environment, thus targeting the colon for the drug release. It was concluded that Eudragit S-100-coated hydrogel beads could serve as a more promising and reliable way to target the colon for drug delivery.Graphical abstract.

Structure/function relationships of bean polysaccharides: A review

Beans are a rich source of high quality protein and oil, and have attracted increasing interest from both nutrition researchers and health-conscious consumers. This review aims to provide a foundation for the future research and development of bean polysaccharides, by summarizing the sources, structure, and functions of bioactive bean polysaccharides. Structure/function relationships are described, for biological activities, such as immunological, antioxidant and anti-diabetes. This will provide useful guidance for further optimization of polysaccharide structure and the development of bean polysaccharides as a novel functional material.