Mucoadhesive microcapsules

Microparticles have unique benefits in the formulation of multiparticulate and multi-unit type pharmaceutical dosage forms allowing improved drug safety and efficacy with favorable pharmacokinetics and patient centricity. On the other hand, the above advantages are served by high and well reproducible quality attributes of the medicinal product where even flexible design and controlled processability offer success as well as possible longer product life-cycle for the manufacturers. Moreover, the specific demands of patients can be taken into account, including simplified dosing regimens, flexible dosage, drug combinations, palatability, and ease of swallowing...

Nanostructured silica-based materials have great potential as drug delivery vehicles for precise and personalized medical applications. As natural nanostructured silica, diatomite biosilica (DB) is recognized as a novel carrier to construct oral/parenteral smart drug delivery systems due to high surface area, biocompatibility, and applicability at low cost, yet the related studies on its use in local delivery routes are still scarce. Herein, we proposed a novel strategy to develop multifunctional nasal drug delivery vehicles based on DB, and demonstrated their versatile performance for enhanced treatment of allergic rhinitis (AR)...

A bioactive compound, collagen peptide (CP), is widely used for biological activities such as anti-photoaging and antioxidant effects, with increased oral bioavailability because of its low molecular weight and high hydrophilicity. However, controlling release time and increasing retention time in the digestive tract for a more convenient oral administration is still a challenge. We developed CP-loaded chitosan (CS) microcapsules via strong and rapid ionic gelation using a highly negative phytic acid (PA) crosslinker...

Novel drug delivery system endows a beneficial method for achieving a desired drug concentration at the appropriate site in the body. The concept of targeted drug delivery has been emerged to localize the drug in the targeted tissue of interest while reducing the relative concentration of the medication in the surrounding tissues. This could be easily accomplished by using different multi-particulate dosage forms like pellets, granules, microcapsules, liposomes, beads. But the major drawbacks associated with them are the use of harsh chemicals and an elevated temperature for their preparation...

Sporopollenin exine capsules (SpECs) are microcapsules derived from the outer shells (exines) of plant spore and pollen grains. This work reports the first clinical study on healthy volunteers to show enhanced bioavailability of vitamin D encapsulated in SpECs from Lycopodium clavatum L. spore grains vs vitamin D alone, and the first evidence (in vitro, ex vivo and in vivo) of mechanisms to account for the enhancement and release of the active in the small intestine. Evidence for mucoadhesion of the SpECs contributing to the mechanism of the enhancement is based on: (i) release profile over time of vitamin D in a double blind cross-over human study showing significant release in the small intestine; (ii) in vivo particle counting data in rat showing preferred retention of SpECs vs synthetic beads; (iii) ex vivo99m Tc labelling and counting data using rat small intestine sections showing preferred retention of SpECs vs synthetic beads; (iv) in vitro mucoadhesion data...

Pollen grains and plant spores have emerged as innovative biomaterials for various applications such as drug/vaccine delivery, catalyst support, and the removal of heavy metals. The natural microcapsules comprising spore shells and pollen grain are designed for protecting the genetic materials of plants from exterior impairments. Two layers make up the shell, the outer layer (exine) that comprised largely of sporopollenin, and the inner layer (intine) that built chiefly of cellulose. These microcapsule shells, namely hollow sporopollenin exine capsules have some salient features such as homogeneity in size, non-toxic nature, resilience to both alkalis and acids, and the potential to withstand at elevated temperatures; they have displayed promising potential for the microencapsulation and the controlled drug delivery/release...

Besides viability protection, a sufficiently prolonged gastrointestinal retention of probiotics has emerged as critically important in improving the functional effectiveness of gastrointestinal delivery of these microorganisms. In this work, we formulated pure, resistant starch-reinforced and chitosan-coated alginate microparticles using an electrospray technique and evaluated their performance as mucoadhesive probiotic formulations for gastrointestinal delivery. In addition, we designed and successfully validated a novel experimental set-up of in vitro wash-off mucoadhesion test, using a portable and low-cost USB microscope for fluorescence imaging...

Background: The gastroretentive drug delivery system is an effective administration route, which can improve the bioavailability of the drug and the therapeutic effect by prolonging the release time of the drug and controlling the release rate in the stomach. Methods: Inspired by the excellent adhesion properties of mussel protein, we prepared novel catechol-grafted chitosan alginate/barium sulfate microcapsules (Cat-CA/BS MCs) with mucoadhesive properties and computed tomography (CT) imaging function for gastric drug delivery...

The design of novel delivery systems to treat vaginal fungal infections is a topic of high interest. Chitosan, being itself antimicrobial and having good mucoadhesive properties, is an excellent candidate as a delivery matrix for active compounds. In this work, chitosan microcapsules containing dry extracts of Argentinean medicinal plants with proved biological properties (Larrea divaricata, L. cuneifolia, L. nitida, Zuccagnia punctata and Tetraglochin andina) were developed through electrospraying and compared with conventionally used tablets containing the same extracts...

INTRODUCTION: In this study, different nifedipine-loaded formulations were prepared to treat pylorospasm, a sphincter muscle disorder characterized by delayed gastric emptying process. The efficacy of formulation was evaluated in patients by subjective assessment, gamma scintigraphic approaches, and confocal microscopy. METHODS: Nifedipine-loaded different formulations such as sucrose bead, pellets, and microparticles (slugging method, ionotropic gelation, and chemical denaturation) were designed...

Chitosan biocompatibility and mucoadhesiveness make it an ideal polymer for antituberculotic drugs microcapsulation for pulmonary delivery. Yet, previous study indicated toxicity problems to J-774.1-cells treated with some medium molecular weight (190-310kDa) chitosan microparticles. As polymer molecular weight is a crucial factor to be considered, this paper describes the preparation and characterization of chitosan (50-190kDa) microparticles containing isoniazid (INH). Cytotoxicity assays were also performed on murine peritoneal (J-774...

Alginate micro beads containing Lactobacillus kefiri (the principal bacteria present in the kefir probiotic drink) were produced by a novel technique based on dual aerosols spaying of alginate based solution and CaCl2 as cross linking agent. Carboxymethylcellulose (CMC) has been also added to the alginate in order to change the physic-chemical properties (viscosity and permeability) of the microbeads. Calcium alginate and CMC are biopolymers that can be used for developing oral drug-delivery systems. These biopolymers have been reported to show a pH-dependent swelling behaviour...

The objective of present research work was to design and characterize the venlafaxine HCl-loaded sodium alginate-based mucoadhesive microcapsules by ionic gelation technique using HPMC K100M as mucoadhesive polymer. The Placket-Burman Design was applied for preliminary screening of the formulations and systematic optimization by using Box-Behnken Design. The prepared microcapsules were characterized for drug content, entrapment efficiency, micromeritic properties, particle size, swelling index, mucoadhesive strength, in vitro drug release and in vivo antidepressant activity...

Pollen grain and spore shells are natural microcapsules designed to protect the genetic material of the plant from external damage. The shell is made up of two layers, the inner layer (intine), made largely of cellulose, and the outer layer (exine), composed mainly of sporopollenin. The relative proportion of each varies according to the plant species. The structure of sporopollenin has not been fully characterised but different studies suggest the presence of conjugated phenols, which provide antioxidant properties to the microcapsule and UV (ultraviolet) protection to the material inside it...

We have designed and evaluated coacervate microcapsules-immobilized multilayer sodium alginate beads (CMs-M-ALG-Beads) for oral drug delivery. The CMs-M-ALG-Beads were prepared by immobilization of doxorubicin hydrochloride (DOX) loaded chitosan/carboxymethyl coacervate microcapsules (DOX:CS/CMCS-CMs) in the core and layers of the multilayer sodium alginate beads. The obtained CMs-M-ALG-beads exhibited layer-by-layer structure and rough surface with many nanoscale particles. The swelling characteristic and drug release results indicated that 4-layer CMs-M-ALG-Beads possessed favorable gastric acid tolerance (the swelling rate <5%, the cumulative drug release rate <3...

The present work deals with various attempts to prepare a gastroretentive formulation of lacidipine for treating gastroparesis. High density sucrose beads were modified by coating with certain polymers, but unfortunately sustained release could not be achieved. Granules were prepared by wet granulation technology using different combinations of polymers and a release of the drug was observed. The method failed to release the drug as per desired specifications. Polymeric coating followed by wet granulation was thought to be a better process to sustain the dissolution rate...

Probiotic bacteria were previously encapsulated in sub-100 µm Ca(2+) alginate microcapsules for enhanced survival in human gastrointestinal tract. The aim of this study is to evaluate the altered mucoadhesive property of the probiotic delivery system by coating it with mucoadhesive chitosan or thiolated chitosan, for prolonged retention in human colon. The results confirmed that cross-linking with calcium ions reduced the mucoadhesive property of alginate hydrogel, thus questioning the intrinsic mucoadhesiveness of uncoated systems...

The objectives of present work was to design and characterize the rabeprazole sodium loaded microcapsules prepared by solvent evaporation technique using ethyl cellulose (EC) based various mucoadhesive polymer, followed by a triple coating with Eudragit L100. The Box-behnken design (BBD) was applied for optimization of formulations containing EC, HPMCK100M and Eudragit L100 as factors for selected responses like entrapment efficiency, mucoadhesive property and drug release in 24 h. The prepared microcapsules were characterized for particle size, drug content, swelling index, mucoadhesive strength, and in vivo antiulcer activity...

Amoxicillin-loaded microcapsules were prepared by ionotropic gelation of sodium alginate (ALG) with chitosan (CS) in presence of calcium chloride as gastroretentive delivery system. The effect of pH, concentration of ALG, CS and calcium chloride, and drug : ALG ratio were optimized in this study for minimizing the degradation of drug in acidic environment and increasing the loading efficacy and mucoadhesive efficiency of microcapsules. The optimum condition for prepared CS-ALG microcapsules was 2%w/v ALG, 0...

Microencapsulation is an accepted process used to achieve controlled release and drug targeting for many years. Mucoadhesion has been a topic of interest in the design of drug delivery systems to prolong its intestinal residence time. Mucoadhesion facilitates the intimate contact of the dosage form with the underlying absorption surface for improved bioavailability of drugs. Aceclofenac is a newer nonsteroidal anti-inflammatory drug (NSAID) having short biological half-life of 4-4.3 h, and therefore a sustained release medication is required to get prolonged effect and to reduce fluctuations in drug plasma concentration levels...