Colon-specific Delivery Research Articles

Formulation and Evaluation of Enteric Coated Matrix Tablets of Mesalamine for Inflammatory Bowel Disease

Mesalamine is a gold standard anti-inflammatory drug used to treat inflammatory bowel illnesses. It's usually used to treat and keep Ulcerative Colitis in remission in mild to moderate cases. Mesalamine is rapidly cleared from circulation after being consumed orally, with an elimination half-life of only one hour. Oral intake of delayed or slow released matrix formulations can acquire therapeutic concentration in the intestines. The goal of this study was to use guar gum as a carrier to develop colon-specific delivery methods for mesalamine. The matrix tablets were made using the direct compression process, which is today regarded as a cost-effective and straightforward manufacturing method. Dip coating was used to coat the tablets with varied concentrations of Eudragit L100 polymer. Tablets were studied in vitro in a variety of dissolution solutions, including 0.1 N HCl (pH 1.2), phosphate buffers pH 6.8 and 7.4, and others. The optimized formulation was subjected to swelling tests. All of the formulations' physicochemical parameters were confirmed to be in line with pharmacopoeial norms. All formulations were subjected to stability tests in accordance with ICH recommendations. The tablets coated with Eudragit L100 (20 percent w/v) had a sustained release of 78.39 percent over 12 hours, while the uncoated tablets released the medication in 9 hours. Tablet stability tests revealed that under accelerated and room temperature storage settings for 6 months, there was reduced degradation. In the colon, the enteric-coated Eudragit L100 coated matrix tablets of mesalamine demonstrated promising site-specific drug delivery.
 Keywords: Mesalamine, Guar gum, Eudragit L100, Direct compression, Inflammatory bowel illnesses

Chitosan-based oral colon-specific delivery systems for polyphenols: recent advances and emerging trends.

Oral colon-targeted delivery systems (OCDSs) have attracted great attention in the delivery of active compounds targeted to the colon for the treatment of colon and non-colon diseases with the advantages of enhanced efficacy and reduced side effects. Chitosan, the second-most abundant biopolymer next to cellulose, has great biocompatibility, is non-toxic, is sensitive to colonic flora and shows strong adhesion to colonic mucus, making it an ideal biomaterial candidate for the construction of OCDSs. Being rich in functional groups, the chitosan structure is easily modified, both physically and chemically, for the fabrication of delivery systems with diverse geometries, including nanoparticles, microspheres/microparticles, and hydrogels, that are resistant to the harsh environment of the upper gastrointestinal tract (GIT). This review offers a detailed overview of the preparation of chitosan-based delivery systems as the basis for building OCDSs. A variety of natural polyphenols with potent biological activities are used to treat diseases of the colon, or to be metabolized as active ingredients by colonic microorganisms to intervene in remote organ diseases after absorption into the circulation. However, the poor solubility of polyphenols limits their application, and the acidic environment of the upper GIT and various enzymes in the small intestine disrupt their structure and activity. As a result, the development of OCDSs for polyphenols has become an emerging and popular area of current research in the past decade. Thus, the second objective of this review is to systematically summarize the most recent research findings in this area and shed light on the future development of chitosan-based OCDSs for nutritional and biomedical applications.

Alpha-mangostin and resveratrol, dual-drugs-loaded mucoadhesive thiolated chitosan-based nanoparticles for synergistic activity against colon cancer cells.

Alpha-mangostin (M) and resveratrol (R), dual-drugs-loaded mucoadhesive thiolated chitosan-based nanoparticles (NPs) coated by Eudragit® S100 (S) were developed for colon-specific delivery and synergistic activity against colon cancer cells. The NPs were prepared by the ionotropic gelation method and coated with S. The particle size and zeta potential of NPs before and after the coating process were observed. The M and R loading efficiency, mucoadhesive properties, as well as release patterns were examined. Moreover, the activity against colon cancer cells of M, R, and NPs were studied for their synergistic activity. M and R-loaded NPs (MR-TNPs) were spherical in shape with sizes of around 540 nm and zeta potential of +39 mV. The S coating of MR-TNPs provided larger particle sizes which offered lower zeta potential. However, it created an increase in M and R loading, prevented M and R release at the upper gastrointestinal tract, and enhanced M and R reaching the colon. S dissolved at pH > 7.0 while thiolated chitosan formed the mucoadhesion, resulting in M and R remaining in the colon and allowing them to enter the colon cancer cells. The half-maximal inhibitory concentration values of NPs was dramatically decreased when M and R were dually loaded into the NPs, which indicated significantly higher activity against colon cancer cells. Moreover, M and R loading at this ratio applied synergistic efficiency. The results illustrated that NPs successfully loaded drugs and achieved synergistic efficiency. This system could be promising in facilitating targeted nanomedicines for the treatment of colon cancer.

Modulation of Naturally Occurring Linear Dipeptide Chirality to Reduce the Affinity for Oligopeptide Transporter 1 and Increase Intestinal Stability for an Enhanced Colon-Targeting Effect in the Treatment of Inflammatory Bowel Disease: An Application of trans-4-l-Hydroxyprolyl-l-serine.

The naturally occurring linear dipeptide JBP923 (trans-4-l-Hyp-l-Ser, HS-tLL) with anti-inflammatory effects showed potential for the treatment of inflammatory bowel disease (IBD). However, colon-specific delivery after oral administration is still a challenge because its absorption is mediated by oligopeptide transporter 1 (PEPT1) in the upper small intestine and because of its instability in the gastrointestinal tract. Therefore, we aimed to enhance the colon-targeting efficiency by modulating HS-tLL chirality to synthesize eight enantiomers. Among these enantiomers, trans-4-d-Hyp-d-Ser, cis-4-l-Hyp-d-Ser, cis-4-d-Hyp-l-Ser, and cis-4-d-Hyp-d-Ser did not work as substrates of PEPT1 and were stable in the gastrointestinal tract, resulting in enhanced colonic accumulation through the paracellular pathway due to the loose tight junctions in IBD. Interestingly, cis-4-d-Hyp-d-Ser exerted the most potent therapeutic effect on IBD. Our findings revealed the impact of chirality on the colonic accumulation of the linear dipeptide, providing strategies for the colon-targeted delivery of the linear dipeptide for the treatment of IBD.

Eudragit-Coated Sporopollenin Exine Microcapsules (SEMC) of Phoenix dactylifera L. of 5-Fluorouracil for Colon-Specific Drug Delivery.

In this study, 5-fluorouracil (5-FU)-loaded pollens of Phoenix dactylifera and their coating with ERS was done and evaluated for the colon-targeted delivery of 5-FU to treat colon cancer. Sporopollenin exine microcapsules (SEMC) from the pollens of Phoenix dactylifera were extracted by the reflux method and 5-FU into SEMC was encapsulated by the vacuum-assisted loading method. 5-FU loaded SEMC was coated with Eudragit® RS-100 (ERS) by the organic solvent-evaporation technique under vacuum to avoid the discharge of 5-FU in the stomach and small intestine. Morphological and physicochemical characterization of drug-loaded SEMC (coated/uncoated) was performed by scanning electron microscopy (SEM), FTIR, XRD, and DSC. The encapsulation and drug loading were determined by the direct method, and an in vitro release study was performed in simulated gastric and intestinal fluids (SGF/SIF). The colon-specific delivery of 5-FU from the SEMC was assessed in terms of pharmacokinetics and gastrointestinal tract distribution after oral administration in rats. The successful encapsulation and loading of 5-FU into SEMC by a vacuum-assisted loading technique and its coating with ERS by a solvent-evaporation technique were achieved. SEM images of uncoated SEMC have shown porous structures, and coating with ERS reserved their morphology with a smooth surface and discrete microstructures and the 5% w/v ERS acetone solution. ERS-coated SEMC sustained the release of 5-FU until 24 h in SIF, while it was up to 12 h only from uncoated SEMC. The maximum plasma concentration (Cmax) of 5-FU from uncoated SEMC was 102.82 μg/mL after 1 h, indicating a rapid release of 5-FU in the upper gastrointestinal tract. This concentration decreased quickly with a half-life of 4 h, AUC0-t was 264.1 μg/mL.h, and MRT0-inf was 5.2 h. The Cmax of 5-FU from ERS-coated SEMC was 19.47 μg/mL at 16 h. The Cmax of 5-FU in small intestines was 406.2 μg/g at 1 h from uncoated SEMC and 1271.5 μg/g at 12 h from coated SEMC. Conclusively, a 249.9-fold higher relative bioavailability of 5-FU was achieved with the ERS-coated SEMC in colon tissues than that from uncoated SEMC.

Optimization study of combined enteric and time-dependent polymethacrylates as a coating for colon targeted delivery of 5-ASA pellets in rats with ulcerative colitis

Formulation design for colon-specific delivery of 5-aminosalicylic acid (5-ASA) could bring some therapeutic benefits in the treatment of ulcerative colitis (UC).In the current study, a 32 full factorial design was used to predict optimum coating composed of two enteric (poly methacrylic acid, methyl methacrylates 1:2 and 1:1) and time-dependent (poly ethyl acrylate, methyl methacrylate, trimethylammonio ethyl methacrylate chloride 1:2:0.1) polymethacrylates for colon-specific delivery of 5-ASA pellets. A unique coating composition and coating level predicted by the model was applied onto either inulin-free 5-ASA pellets or inulin-bearing 5-ASA pellets and the coated pellets were examined by dissolution test in-vitro. The coated pellets were also tested in a rat model of UC and compared with the a commercially available colonic delivery system of 5-ASA.The ratio of the two enteric polymethacrylates and time-dependet polymethacrylate of 16:64:20 w/w at a coating level of 15% was discovered as the optimum coating for delivery of 5-ASA pellets to the colon. In general, the coated pellets offered a better therapeutic outcome compared to commercially available colonic delivery system of 5-ASA and uncoated pellets in terms of colitis activity index and the colon's tissue enzymes of MDA and GSH.It seems that the coating composed of enteric and pH-dependent polymethacrylates could tune up the rate of drug release from 5-ASA-coated pellets and trigger drug release based on pH and time.

Design of mucoadhesive gellan gum and chitosan nanoparticles intended for colon-specific delivery of peptide drugs

Nanotechnology has been widely used in the development of polymer nanocarriers for the oral delivery of biomolecules. The use of nanostructured systems can improve drug delivery and help to overcome the disadvantages of the oral administration of peptides. Nanoparticles (NPs) based on gellan gum (GG) and chitosan (CS) blends were prepared through polyelectrolyte complexation. The influence of pH on the zeta potential (ZP) of polymers allowed the selection of pH 5.0 as the most suitable pH for the complexation of polyelectrolytes. The effects of the polymer mass ratio and addition order on the formation and physicochemical properties of the NPs were evaluated. All NPs showed high positive ZP (> + 30 mV), which ensures electrostatic stability. The order of addition of the polymers influenced the particle size. Nanoscale structures (575.30–974.60 nm) were formed when GG (0.5–3 mg) was dripped into the CS dispersion (0.75–4.5 mg); however, when CS was dripped in the GG dispersion, particle aggregation occurred (sizes >5000 nm). Polymyxin B (PMB) nanoencapsulation reduced the particle size, mainly at low GG mass (1.5 mg). The PMB–polymer interactions were detected by Fourier transform infrared spectroscopy. The X-ray diffraction data indicated the formation of more organized structures with a higher degree of crystallinity. Scanning electron microscopy revealed spherical and uniform NPs. The mucoadhesive capability of the NPs was also demonstrated. The NP2_1 and NP2_3 released the lowest amount of drug in HCl 0.1 N (pH 1.2) (<29%), and the drug release rate was controlled in a phosphate buffer 0.1 M (pH 6.8) (<60%). The important findings of this study suggest that nanocarriers with tailored properties may be utilized to overcome the challenges of oral administration of peptides, such as PMB, contributing to the advances in the search for alternatives to the oral administration of PMB.

Cellulose Nanofibers Improve the Performance of Retrograded Starch/Pectin Microparticles for Colon-Specific Delivery of 5-ASA.

Cellulose nanofibers (CNF) were employed as the nanoreinforcement of a retrograded starch/pectin (RS/P) excipient to optimize its colon-specific properties. Although starch retrogradation ranged from 32 to 73%, CNF addition discretely disfavored the RS yield. This result agrees with the finding that in situ CNF reduces the presence of the RS crystallinity pattern. A thermal analysis revealed that the contribution of pectin improves the thermal stability of the RS/CNF mixture. Through a complete factorial design, it was possible to optimize the spray-drying conditions to obtain powders with high yield (57%) and low moisture content (1.2%). The powders observed by Field Emission Gum Scanning Electron Microscopy (FEG-SEM) had 1–10 µm and a circular shape. The developed methodology allowed us to obtain 5-aminosalicilic acid-loaded microparticles with high encapsulation efficiency (16–98%) and drug loading (1.97–26.63%). The presence of CNF in RS/P samples was responsible for decreasing the burst effect of release in simulated gastric and duodenal media, allowing the greatest mass of drug to be targeted to the colon. Considering that spray-drying is a scalable process, widely used by the pharmaceutical industry, the results obtained indicate the potential of these microparticles as raw material for obtaining other dosage forms to deliver 5-ASA to the distal parts of gastrointestinal tract, affected by inflammatory bowel disease.

Development of enteric-coated, biphasic chitosan/HPMC microcapsules for colon-targeted delivery of anticancer drug-loaded nanoparticles

Oral delivery of anticancer drug-loaded nanoparticles (NPs) to the colon offers opportunities to improve colorectal cancer (CRC) treatment by increasing the free drug concentration at tumour sites and/or enhancing NP accumulation in tumours. Indomethacin, 5-FU and curcumin, were entrapped separately in Eudragit RS NPs (approximately 10% w/w loading) using nanoprecipitation and incorporated in biphasic chitosan/HPMC microcapsules (MCs) using aerosolisation. The MCs were designed to release NPs primarily in the colon following chitosan breakdown by bacterial enzymes. Around 10% of the drug-loaded NPs was released from MCs in simulated intestinal fluid (SIF) in 6 h and 20% in simulated colon fluid (SCF). Indomethacin release from MCs was absent in simulated gastric fluid (SGF) and restricted to around 10% in SIF and SCF, respectively, demonstrating potential for delivering a large fraction of contained drug to the colon. Curcumin release from NPs or NP-loaded MCs was negligible in SGF, SIF and SCF, revealing opportunities for delivery of curcumin-loaded NPs to the colon for accumulation in tumours. Curcumin-loaded NPs reduced proliferation of human colon adenocarcinoma HT-29 cells by 83% compared with 50% for free curcumin. These findings demonstrate the potential of chitosan/HPMC microcapsules as a colon-specific delivery vehicle for oral nanomedicines directed against colorectal cancer.

3D printed systems for colon-specific delivery of camptothecin-loaded chitosan micelles

The use of 3D printing technology in the manufacturing of drug delivery systems has expanded and benefit of a customized care. The ability to create tailor-made structures filled with drugs/delivery systems with suitable drug dosage is especially appealing in the field of nanomedicine. In this work, chitosan-based polymeric micelles loaded with camptothecin (CPT) were incorporated into 3D printing systems (printfills) sealed with an enteric layer, aiming to protect the nanosystems from the harsh environment of the gastrointestinal tract (GIT). Polymeric micelles and printfills were fully characterized and, a simulated digestion of the 3D systems upon an oral administration was performed. The printfills maintained intact at the simulated gastric pH of the stomach and, only released the micelles at the colonic pH. From there, the dissolution media was used to recreate the intestinal absorption and, chitosan micelles showed a significant increase of the CPT permeability compared to the free drug, reaching an apparent permeability coefficient (Papp) of around 9×10-6 cm/s in a 3D intestinal cell-based model. The combination of 3D printing with nanotechnology appears to have great potential for the colon-specific release of polymeric micelles, thereby increasing intestinal absorption while protecting the system/drug from degradation throughout the GIT.

FORMULATION AND EVALUATION OF BUDESONIDE PELLETS CONTAINING NATURAL GUMS FOR COLON TARGETING

Pellets formulation with natural gums. The formulation of an enzyme as well as pH dependant pellets containing natural gums such as Mornings oleifera gum Lam. (MOG) and Cyamopsis tetragonolobus gum Taub. (CTG) were used for enzyme dependant release and further coating is provided to shows colon-specific delivery. Extrusion and spheronization techniques were used for the preparation of pellets. Pellets of budesonide evaluated for various properties such as flow behavior, physical properties such as sphericity, roundness, aspect ratio, hardness, and friability also investigated in vitro and in vivo targeting in rabbit. Preparation of pellets was done by using extrusion and spheronization method with the use of optimized concentration of gums those were 7.5% and 10% for CTG and MOG respectively and proportion of solvent mixture of water and Isopropyl alcohol in the ratio of 80:20. Pellets of budesonide evaluated for various properties includes flow behavior, physical properties such as sphericity, roundness, aspect ratio, hardness, and friability and found that all properties as per official limit also in vitro release study found that release of uncoated pellets in a sustained manner in 0.1N HCl for 2h due to swelling of natural gum, therefore further step of the coating was done in fluidized bed coater to prevent the release of drug in the upper part of GIT and after coating found that In vitro release of drug at the colonic environment and it confirmed with in vivo investigation in rabbit with X-ray examination of targeting and found that pellets reach at colonic part without disintegration. The use of natural gums for preparation of pellets in optimized concentration and wetting agent produce a formulation with all required chemical and physical properties and it gives effective in vitro release and also shows In vivo targeting in rabbit and due to use of natural gum for preparation of pellets also reduce some problems of metabolism of synthetic excipients.

Development of Budesonide Oral Colon Specific Drug Delivery System using Interpolymer Complexation Method

Abstract: Background: Oral bioavailability of Budesonide is 10% due to its extensive first pass metabolism, its high volume of distribution and 85-90% of protein binding. Protection of drug release in stomach and targeting drug to colon which is an absorption site of drug is an attempt to improve therapeutic efficacy. The objective of this study was to develop interpolymer complex microspheres of Budesonide for oral colon specific drug delivery. Methods: Emulsion solvent evaporation method was used in the preparation of microspheres. Microspheres prepared at different polymer ratio and surfactant concentration were analysed for its mean particle size, surface morphology, flow property, drug release, % encapsulation efficiency. Results: Microspheres prepared with 3:5 polymer ratios F4 was optimized with respect to its % EE, in vitro drug release and percentage yield. Drug release from formulated tablets containing microspheres of 3:5 polymer ratios showed an extended release up to 12 h in pH buffer 7.4. Interpolymer complexation was confirmed by FT-IR studies, compatibility of drug with excipients by DSC indicated no significant changes with drug. SEM studies revealed formation of round microspheres with pervious and uneven surface. In vitro release data from microspheres was analysed by kinetic model fitting for mechanism of drug release. Microspheres showed 5-10% of drug release in pH 1.2 which was further prevented by formulating coated tablets of microspheres using cellulose acetate phthalate. Conclusion: Targeted colon specific drug delivery of Budenoside with extended release up to 12 h was successfully achieved by formulation of tablets containing microspheres prepared by interpolymer complexation technique. Key words: Budesonide, Colon Specific Delivery, Interpolymer Complexation, Microspheres, Cellulose Acetate phthalate.

Formulation and optimisation of lamivudine‐loaded Eudragit ® S 100 polymer‐coated pectin microspheres for colon‐specific delivery

This investigation is to find a prolonged or delayed drug release system, exclusively for the treatment of hepatitis‐B to reduce the side effects, which arise when conventional solid dose forms are administered. To pursue this goal, lamivudine‐loaded Eudragit‐coated pectin microspheres have been formulated employing water/oil (W/O) emulsion evaporation strategy. The formulation was optimised using a 34 factorial design. A drug to polymer ratio of 1:2, the surfactant of 1 ml, the volume of 50 ml of processing medium with a stirring speed of 2500 rpm were found to be the optimal parameters to obtain the lamivudine‐loaded Eudragit‐coated pectin microspheres formulation with a high drug entrapment efficiency of 89.44% ± 1.44%. The in vitro release kinetics of lamivudine was a suitable fit to the Higuchi model, indicating a diffusion‐controlled release with anomalous transport. The obtained microspheres were then subjected to different characterisation studies, including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD). The results of this study clearly indicate that Eudragit‐coated pectin microspheres could be the promising controlled release carriers for colon‐specific delivery of lamivudine in the presence of rat cecal content.

Expedition of Eudragit® Polymers in the Development of Novel Drug Delivery Systems.

Eudragit® polymer has been widely used in film-coating for enhancing the quality of products over other materials (e.g., shellac or sugar). Eudragit® polymers are obtained synthetically from the esters of acrylic and methacrylic acid. For the last few years, they have shown immense potential in the formulations of conventional, pH-triggered, and novel drug delivery systems for incorporating a vast range of therapeutics including proteins, vitamins, hormones, vaccines, and genes. Different grades of Eudragit® have been used for designing and delivery of therapeutics at a specific site via the oral route, for instance, in stomach-specific delivery, intestinal delivery, colon-specific delivery, mucosal delivery. Further, these polymers have also shown their great aptitude in topical and ophthalmic delivery. Moreover, available literature evidences the promises of distinct Eudragit® polymers for efficient targeting of incorporated drugs to the site of interest. This review summarizes some potential researches that are being conducted by eminent scientists utilizing the distinct grades of Eudragit® polymers for efficient delivery of therapeutics at various sites of interest.

Oxidized starch/CuO bio-nanocomposite hydrogels as an antibacterial and stimuli-responsive agent with potential colon-specific naproxen delivery

In this work, a series of oxidized starch-based bio-nanocomposites (OS/CuO) were prepared and investigated as colon drug delivery vehicles. The appearance of peaks at 400–800 cm−1 of FTIR spectrum, as well as, peaks at 2θ 35°, 39°, and 49° of XRD spectrum could be a good sign for successful synthesis of the CuO within hydrogel network. The effect of Cu2+ concentration on swelling, NPX loading, and release behavior was examined and the highest value obtained for the C2 sample. Moreover, C4 displayed the highest antibacterial activity. Obtained results indicated that the prepared systems are suitable for use in medical applications.

Colon specific enzyme responsive oligoester crosslinked dextran nanoparticles for controlled release of 5-fluorouracil.

Targeting bioactives selectively to diseased sites is one of the most challenging aspects of cancer therapy. Herein, fabrication of colonic enzyme-responsive dextran based oligoester crosslinked nanoparticles is reported for the controlled release of 5-fluorouracil (5-FU) - an anticancer drug. The 5-FU drug loaded nanoparticles (DNPs, size ~237±25nm, ζ-potential -17.0±3mV) were developed by the in-situ crosslinking of dextran with a bifunctional telechelic oligoester followed by the physical drug encapsulation via nanoprecipitation. Drug encapsulation efficiency and drug loading capacity of DNPs were found to be ~76% (±0.1) and ~8% (±0.1), respectively. The DNPs were demonstrated to release the encapsulated drug selectively in the presence of dextranase enzyme. The in vitro release kinetics assay revealed that the DNPs released about 75% (±4) of the entrapped drug within 12h of incubation with dextranase enzyme. No drug was released in a control experiment where DNPs were exposed to pH conditions encountered in the stomach and small intestine. Moreover, the treatment of HCT116 colon cancer cell line with the developed DNPs highlighted its biocompatibility as well as dextranase triggered cytotoxicity. The developed system offers an avenue to reduce the non-specific cytotoxicity of the encapsulated 5-FU, and a colon specific delivery of the encapsulated drug in response to the dextranase enzyme.

Application of zein and chitosan in the development of a colon-specific delivery system

Silan/biopolymer microgels for functionalization of cotton fabric: dual responsive pH and temperature and antibacterial propertiesAmina L. Mohamed

Interpolymer Complexes of Eudragit® Copolymers as Novel Carriers for Colon-Specific Drug Delivery.

Interpolymer complexes (IPC) based on Eudragit® EPO and Eudragit® S100 were investigated as potential carriers for oral controlled drug delivery to the colon. IPC samples were prepared by mixing copolymer solutions in organic solvents (ethanol, isopropanol:acetone mixture (60:40, % v/v) and tetrahydrofuran). According to the data of elemental analysis, FTIR-spectroscopy, X-ray photoelectron spectroscopy and thermal analysis these IPCs have excess of anionic copolymer (Eudragit® S100) in their structure; they are stabilized by hydrogen and ionic intermacromolecular bonds and do not include free copolymer domains. IPC have pH-independent swelling properties in the media mimicking gastrointestinal tract (GIT) conditions and provide colon-specific delivery of indomethacin in buffer solutions (pH 1.2; 5.8; 6.8; 7.4) and in biorelevant media (fasted state simulated gastric fluid, fasted state simulated intestinal fluid—version 2 and fasted stated simulated colonic fluid).

Modified Pectins for Colon-Specific Drug Delivery

Treatment of local diseases such as ulcerative colitis, Crohn’s disease, irritable bowel syndrome and colonic cancer by targeting drug to the colon is a viable approach. Due to gastric degradation of drugs, proteins and peptides, only minimum amount of drug gets absorbed when administered orally and shows little therapeutic activity. Hence the strategy of delivering drugs to colon known as colon targeted drug delivery evolved. Pectin a naturally occurring biodegradable polysaccharide has gained importance as a carrier for colon-specific delivery attributed to swelling nature as well as the ability to resist gastric degradation. This review describes the chemistry of pectin, mechanism of action and various novel modified pectin formulations aimed at targeting the colon.

Lipid-based nanocarrier-mediated targeted delivery of celecoxib attenuate severity of ulcerative colitis.

Ulcerative colitis is a chronic mucosal inflammatory condition that adversely affects colon and rectum. Celecoxib is a selective inhibitor of inducible cyclooxygenase-2 (COX-2) and is prescribed for the management of pain and other inflammatory disorders. The physicochemical properties of celecoxib limit its clinical potency. Here we developed nanostructured lipid carriers (NLCs) using Generally Recognized as Safe and US-FDA approved compounds for encapsulating celecoxib. Present study was aimed to evaluate efficacy of eudragit-S100-coated celecoxib-loaded NLCs against DSS-induced colitis in mice. NLCs were formulated by hot-melt method and possessed the average particle size of 250.90nm and entrapment efficiency (%) was 59.89%. Furthermore, size, shape and morphology of NLCs were confirmed using TEM, SEM and AFM. The blank NLCs were cytocompatible against hTERT-BJ cells up to a dose of 200μg/ml. Treatment with celecoxib-loaded NLCs alleviated severity of colitis as demonstrated by disease activity index, colon length, fecal occult blood test, and histopathological analysis. Moreover, treatment with celecoxib-loaded NLCs reduced disintegration of goblets cells and restores sulfomucin in colon. Celecoxib-nanoformulation markedly reduced colonic inflammation as evidenced by decreased immunohistochemical expression of COX-2 and iNOS. The observations of study suggest that lipid-based colon specific delivery of celecoxib may be used for management of colitis.