orabase and carboxypolymethylene

It was the aim of this study to assess in vitro methods for the characterization of mucoadhesive hydrogels for their potential to predict the residence time on human buccal mucosa.. Mixtures of hydrogels comprising hydroxyethyl cellulose (HEC), sodium carboxymethyl cellulose (CMC), xanthan gum (XTGM), hyaluronic acid sodium salt (HA), sodium alginate (ALG), carbopol (CP) as well as polycarbophil (PCP) and porcine mucus were analysed for relative rheological synergism. Furthermore, hydrogels were characterized for their texture and mechanical properties. For the assessment of mucoadhesive strength of formulations tensile studies were performed on porcine buccal mucosa. To facilitate a direct comparability of data the residence time of stained hydrogels was determined ex vivo on porcine buccal mucosa and in the oral cavity of volunteers.. The extent of relative rheological synergism was in good agreement with data from in vivo residence time studies. Results of tensile studies were further effected by textural properties of hydrogels leading to a restricted correlation with data from the in vivo experiment. The resistance towards removal by artificial saliva flow ex vivo revealed the highest correlation to the in vivo experiment with increasing mucosal residence time in the rank order CP < HEC, HA, ALG, PCP < CMC < XTGM.. This overview of measurement principles to predict the residence time of hydrogels for buccal application in humans may be a potent tool for the development of semisolid intraoral formulations.

Topics: Acrylic Resins; Adhesives; Administration, Buccal; Adult; Alginates; Animals; Carboxymethylcellulose Sodium; Cellulose; Correlation of Data; Drug Compounding; Drug Delivery Systems; Humans; Hyaluronic Acid; Hydrogels; In Vitro Techniques; Mouth; Mouth Mucosa; Polysaccharides, Bacterial; Swine; Young Adult

Currently available anti-ulcer drugs suffer from serious side effects which limited their uses and prompted the need to search for a safe and efficient new anti-ulcer agent. Boswellia gum resin (BR) emerged as a safe, efficient, natural, and economic potential cytoprotective agent. Thus, it is of medical importance to develop gastroretentive (GR) formulations of BR to enhance its bioavailability and anti-ulcer efficacy. Early attempts involved the use of organic solvents and non-applicability to large-scale production. In this study, different tablet formulations were prepared by simple direct compression combining floating and bioadhesion mechanisms employing hydroxypropyl methylcellulose (HPMC), sodium carboxymethyl cellulose (SCMC), pectin (PC), and/or carbopol (CP) as bioadhesive polymers and sodium bicarbonate (SB) as a gas former. The prepared tablets were subjected for assessment of swelling, floating, bioadhesion, and drug release in 0.1 N HCl. The optimized GR formulation was examined for its protective effect on the gastric ulcer induced by indomethacin in albino rabbits compared with lactose tablets. The obtained results disclosed that swelling, floating, bioadhesion, and drug release of the GR tablets of BR depend mainly on the nature of the matrix and the ratio of polymer combinations. Moreover, a combination of SCMC-CP in a ratio of 2:1 (SCP21) exhibited desirable floating, bioadhesion, swelling, and extended drug release. Also, a 6-h pretreatment with SCP21 tablets decreased the severity of inflammation and number of bleeding spots among ulcer-induced rabbits in comparison to those treated with lactose tablets.

Topics: Acrylic Resins; Animals; Anti-Ulcer Agents; Biological Availability; Boswellia; Carboxymethylcellulose Sodium; Chemistry, Pharmaceutical; Drug Liberation; Excipients; Hypromellose Derivatives; Indomethacin; Male; Pectins; Polymers; Protective Agents; Rabbits; Resins, Plant; Sodium Bicarbonate; Stomach Ulcer; Tablets

One of the major challenges faced by therapeutic polypeptides remains their invasive route of delivery. Oral administration offers a potential alternative to injections; however, this route cannot be currently used for peptides due to their limited stability in the stomach and poor permeation across the intestine. Here, we report mucoadhesive devices for oral delivery that are inspired by the design of transdermal patches and demonstrate their capabilities in vivo for salmon calcitonin (sCT). The mucoadhesive devices were prepared by compressing a polymeric matrix containing carbopol, pectin and sodium carboxymethylcellulose (1:1:2), and were coated on all sides but one with an impermeable and flexible ethyl cellulose (EC) backing layer. Devices were tested for in vitro dissolution, mucoadhesion to intestinal mucosa, enhancement of drug absorption in vitro (Caco-2 monolayer transport) and in vivo in rats. Devices showed steady drug release with ≈75% cumulative drug released in 5h. Devices also demonstrated strong mucoadhesion to porcine small intestine to withstand forces up to 100 times their own weight. sCT-loaded mucoadhesive devices exhibited delivery of sCT across Caco-2 monolayers and across the intestinal epithelium in vivo in rats. A ≈52-fold (pharmacokinetic) and ≈44-fold (pharmacological) enhancement of oral bioavailability was observed with mucoadhesive devices when compared to direct intestinal injections. Oral delivery of devices in enteric coated capsules resulted in significant bioavailability enhancement.

Topics: Acrylic Resins; Adhesiveness; Administration, Oral; Animals; Bone Density Conservation Agents; Caco-2 Cells; Calcitonin; Carboxymethylcellulose Sodium; Drug Carriers; Drug Delivery Systems; Humans; Intestinal Absorption; Intestinal Mucosa; Male; Pectins; Rats; Rats, Sprague-Dawley; Swine

Recent developments in pharmaceutical technology have facilitated the design and production of modified release formulas for drugs whose physical, chemical or biological properties impede release and thus might compromise their efficacy or safety. One such drug is morphine, whose short half-life requires repeated doses at short intervals. The use of biocompatible polymers such as ethylcellulose has made it possible to develop microencapsulated formulations which facilitate liquid, sustained-release pharmaceutical formulas for oral administration. We developed a stable final formulation of morphine with an acceptable release profile by comparing the rheological properties and stability of formulations with different thickeners (xanthan gum, Carbopol, and carboxymethylcellulose with microcrystalline cellulose) at different concentrations from 0.25% to 1.0%. Release assays in a Franz-type cell were done to determine the most suitable release profile for the formulation.

Topics: Acrylic Resins; Administration, Oral; Analgesics, Opioid; Carboxymethylcellulose Sodium; Cellulose; Delayed-Action Preparations; Drug Compounding; Membranes, Artificial; Morphine; Polysaccharides, Bacterial; Polyvinyls; Rheology; Suspensions

The purpose of the present research was to develop bioadhesive buccal tablets for Felodipine (FDP) and Pioglitazone (PIO), low bioavailability drugs, in a combined dosage form for the management of diabetes and hypertension. Buccal tablets were prepared by direct compression method using bioadhesive polymers hydroxypropyl methyl cellulose, sodium carboxymethyl cellulose, and carbopol, alone or in combination of two polymers, and were evaluated for physicochemical properties, swelling index, in vitro bioadhesion, in vivo residence time, in vitro drug release, and ex vivo permeation through porcine buccal membrane. Formulation (PF6) showed peak detachment force (3.12 N), work of adhesion (0.72 mJ), swelling index (196%), erosion (10.8%), in vivo residence time of 280 min, in vitro drug release (99.65% and 98.96% in 6 h for FDP and PIO, respectively) with higuchi model release profile and permeated 66.1 and 64.6 % with a flux of 0.118 and 0.331 mg/h/cm(2) of FDP and PIO through porcine buccal membrane. The bioavailability study for optimized formulation (PF6) in pigs showed 2.05- and 2.13-times statistically significant (p < 0.05) improvement in bioavailability for FDP and PIO, respectively, after administration of buccal tablets compared to oral suspension. The ex vivo-in vivo correlation was found to have a biphasic pattern and followed type A correlation. The stability of the PF6 was studied and no significant changes were detected in drug content and in vitro release and ex vivo permeation through porcine buccal membrane after 6 months.

Topics: Acrylic Resins; Adhesiveness; Administration, Buccal; Adult; Animals; Antihypertensive Agents; Biological Availability; Carboxymethylcellulose Sodium; Drug Combinations; Drug Stability; Drug Storage; Excipients; Felodipine; Humans; Hypoglycemic Agents; Hypromellose Derivatives; Male; Methylcellulose; Permeability; Pioglitazone; Polyvinyls; Species Specificity; Swine; Tablets; Thiazolidinediones; Time Factors; Young Adult

Exogenous melatonin (MT) has significant neuroprotective roles in Alzheimer's and Parkinson's diseases. This study investigates the delivery MT to brain via nasal route as a polymeric gel suspension using central brain microdialysis in anesthetized rats.. Micronized MT suspensions using polymers [carbopol, carboxymethyl cellulose (CMC)] and polyethylene glycol 400 (PEG400) were prepared and characterized for nasal administration. In vitro permeation of the formulations was measured across a three-dimensional tissue culture model EpiAirway(™). The central brain delivery into olfactory bulb of nasally administered MT gel suspensions was studied using brain microdialysis in male Wistar rats. The MT content of microdialysis samples was analyzed by high performance liquid chromatography (HPLC) using electrochemical detection. The nose-to-brain delivery of MT formulations was compared with intravenously administered MT solution.. MT suspensions in carbopol and CMC vehicles have shown significantly higher permeability across Epiairway(™) as compared to control, PEG400 (P < 0.05). The brain (olfactory bulb) levels of MT after intranasal administration were 9.22, 6.77 and 4.04-fold higher for carbopol, CMC and PEG400, respectively, than that of intravenous MT in rats. In conclusion, microdialysis studies demonstrated increased brain levels of MT via nasal administration in rats.

Topics: Acrylic Resins; Administration, Intranasal; Animals; Antioxidants; Biological Transport; Carboxymethylcellulose Sodium; Chromatography, High Pressure Liquid; Gels; Injections, Intravenous; Male; Melatonin; Microdialysis; Olfactory Bulb; Permeability; Polyethylene Glycols; Polyvinyls; Rats; Rats, Wistar

Mucoadhesive polymer-coated pellets containing metformin hydrochloride were prepared by the powder-layering technique using a centrifugal fluidizing (CF)-granulator. Four high-viscosity polymers were applied to make the pellets: 1) hydroxymethylcellulose (HPMC), 2) sodium alginate (Na-Alg), 3) HPMC/Carbopol, and 4) sodium carboxylmethylcellulose (Na-CMC). The physical crushing test, mucoadhesive test, zeta-potential test, in vitro release study and observation of gastroretention state of the dosage form were performed to investigate the pellets. The strong adhesive interaction between the Na-CMC-coated pellets and the mucin disc was obtained by mucoadhesive test. Na-Alg was most effective among the polymers used in changing the value of zeta potential of the mucin solution by the interaction between a polymer and a mucin particle. Results from drug dissolution study showed that over 95% of the drug from all the four pellets was released before 2 h, while Na-CMC- and Na-Alg-coated pellets showed a moderate sustained-release in SGF (simulated gastric fluid) and SIF (simulated intestine fluid), respectively. In conclusion, Na-CMC and Na-Alg seem to be promising candidates for mucoadhesive formulation and further studies to improve the sustained-release property are underway for achieving the ultimate goal of once-a-day formulation of metformin hydrochloride.

Topics: Acrylic Resins; Adhesiveness; Alginates; Animals; Capsules; Carboxymethylcellulose Sodium; Chemistry, Pharmaceutical; Delayed-Action Preparations; Drug Carriers; Gastric Mucosa; Glucuronic Acid; Hardness; Hexuronic Acids; Hypoglycemic Agents; Hypromellose Derivatives; Kinetics; Metformin; Methylcellulose; Mucins; Polymers; Polyvinyls; Powders; Rats; Solubility; Viscosity

Fluconazole mucoadhesive buccal films were prepared using film forming polymers namely; hydroxypropyl methyl cellulose (HPMC), hydroxyethyl cellulose (HEC), chitosan, Eudragit and sodium alginate (SALG) either alone or in combination with bioadhesive polymers. The bioadhesive polymers studied were sodium carboxymethyl cellulose (SCMC), Carbopol 974P, and polycarbophil (AA-A). The prepared films were characterized by means of film thickness, surface pH, swelling capacity, in vitro adhesion, in vivo residence time, in vitro drug release and in vivo drug release to determine the amount of drug release from selected film formulae using microbiological assay and HPLC. Optimum release behavior, convenient bioadhesion, acceptable elasticity were exhibited by film containing 2% HPMC and 1% SCMC (fresh or stored for 6 months). Determination of the amount of drug released in saliva after application of the selected fluconazole films confirmed the ability of the film to deliver the drug over a period of approximately 300 minutes and to reduce side effects and possibility of drug interaction encountered during systemic therapy of fluconazole, which would be beneficial in the case of oral candidiasis.

Topics: Acrylic Resins; Adhesiveness; Adult; Alginates; Antifungal Agents; Candidiasis, Oral; Carboxymethylcellulose Sodium; Cheek; Female; Fluconazole; Glucuronic Acid; Hexuronic Acids; Humans; Hypromellose Derivatives; Male; Methylcellulose; Polyvinyls; Solubility

Glipizide is one of the most commonly prescribed drugs for treatment of type 2 diabetes. Oral therapy with glipizide comprises problems of bioavailability fluctuations and may be associated with severe hypoglycaemia and gastric disturbances. As a potential for convenient, safe and effective antidiabetic therapy, the rationale of this study was to develop a transdermal delivery system for glipizide. For this purpose, inclusion complexes of the drug in beta-cyclodextrin (beta-CyD), dimethyl-beta-cyclodextrin (DM-beta-CyD), hydroxypropyl-beta-cyclodextrin (HP-beta-CyD), and hydroxypropyl-gamma-cyclodextrin (HP-gamma-CyD) were prepared. Several percutaneous formulations of the drug and the prepared complexes in different bases (o/w emulsion, polyethylene glycol, carboxymethyl cellulose and Carbopol) were developed. Release studies revealed an improved release of the drug from formulations containing glipizide-CyD complexes. Ex vivo permeation studies through full thickness rat abdominal skin were conducted, whereby the effect of several conventional penetration enhancers (propylene glycol [PG], oleic acid, urea, dimethyl sulfoxide, menthol, limonene and cineole) was monitored. Highest flux was obtained from ointments prepared with Carbopol gel base containing a combination of PG and oleic acid as well as ointments prepared in the same base utilizing glipizide-DM-beta-CyD complex and urea. In vivo studies on diabetic male Wistar rats revealed a marked therapeutic efficacy sustained for about 48 hours. In this respect, two formulations showed best biological performance. In the first formulation, the drug was incorporated in Carbopol gel base in the presence of 20% PG together with 15% oleic acid. The second was prepared by incorporating glipizide-DM-beta-CyD complex in Carbopol gel base in presence of 15% urea. The glucose tolerance test showed suppression of hyperglycaemia induced in glucose-loaded rats. The above-mentioned results might shed a strong beam of light on the feasibility of using glipizide in a transdermal delivery system for treatment of type 2 diabetes with the aim of improving both patient compliance and pathophysiology of the disease.

Topics: Acrylic Resins; Adjuvants, Pharmaceutic; Administration, Cutaneous; Animals; Biological Availability; Blood Glucose; Carboxymethylcellulose Sodium; Cyclodextrins; Diabetes Mellitus, Experimental; Drug Delivery Systems; Emulsions; Glipizide; Glucose Tolerance Test; Hypoglycemic Agents; Male; Polyethylene Glycols; Polyvinyls; Rats; Rats, Wistar; Skin Absorption; Solubility

The aim of this study was to add knowledge to the existing theories of mucoadhesion and to review mucoadhesive polymers based on their ability to form non-covalent bonds with mucus glycoprotein. Resonant mirror biosensor was used to study the candidate mucoadhesive polymers hydroxypropyl methylcellulose, carboxymethylcellulose, Carbopol, hyaluronate, alginate and chitosan. Bovine submaxillary mucin was chosen as substrate, representing the major glycosylated protein in mucus. For comparison, non-glycosylated bovine serum albumin was used as an alternative substrate. The results of this study reveal that there is a clear correlation between the ionization state of the polymer, which is dependent on the pH of the surrounding environment, and its binding behavior. Ionizable polymers need to be in their unionized state to be able to form non-covalent bonds with mucus glycoprotein. Acidic polymers display binding behavior only at pH around or lower than their corresponding pK(a) values and basic polymers vice versa. Chitosan was found to be the most mucoadhesive polymer. Unionizable polymers like hydroxypropyl methylcellulose did not display any affinity for mucus glycoprotein. Unionized amino- and carboxyl groups on polymers were found to be important structural feature of polymer for the formation of weak chemical bonds to mucus glycoproteins.

Topics: Acrylic Resins; Adhesiveness; Alginates; Animals; Binding, Competitive; Biosensing Techniques; Carboxymethylcellulose Sodium; Cattle; Chitosan; Glucosamine; Glycoproteins; Hyaluronic Acid; Hydrogen-Ion Concentration; Lactose; Methylcellulose; Molecular Structure; Mucins; Mucus; Polyvinyls; Protein Binding; Serum Albumin, Bovine; Technology, Pharmaceutical

Aspergillus fumigatus NRRL 2346 is the producer of fumagillin, an antitumor antibiotic that inhibits angiogenesis. This strain is very difficult to grow reproducibly in shake flasks owing to an extreme form of pellet growth and extensive wall growth. The effects of carboxymethylcellulose (CMC) and carboxypolymethylene (Carbopol) on growth and fumagillin production by A. fumigatus were investigated. By adding the polymers to the fermentation medium, the growth form of the mold was changed from a single large glob to small reproducible pellets, and wall growth was diminished to a minimum. Carbopol, at a lower concentration, was more effective than CMC in improving both morphology and production. Small pellets were produced which favored fumagillin biosynthesis. 1.5% (wt/vol) CMC and 0.3% (wt/vol) Carbopol were found to be the optimum concentrations; higher levels increased viscosity to an unacceptable level.

Topics: Acrylic Resins; Anti-Bacterial Agents; Aspergillus fumigatus; Carboxymethylcellulose Sodium; Cyclohexanes; Dose-Response Relationship, Drug; Fatty Acids, Unsaturated; Hyphae; Polyvinyls; Sesquiterpenes; Spores, Fungal

The residence time of apomorphine mucoadhesive preparations incorporating 99mTc labeled colloidal albumin in rabbit nasal cavity was evaluated by gamma scintigraphy. This technique was used to compare the nasal clearance of preparations based either on Carbopol 971P((R)) or lactose (control), each with and without apomorphine, or carboxymethylcellulose with apomorphine. The planar 1-min images showed an excipient-dependent progressive migration of radioactivity with time from the nasal cavity to the stomach and intestine. Thirty minutes post insufflation, the percentages of the formulations cleared from the nasal cavity were 47% for lactose, 26% for lactose/apomorphine, 10% for Carbopol 971P((R)), and 3% for both Carbopol 971P((R))/apomorphine and carboxymethylcellulose/apomorphine. Three hours post insufflation, the percentages of the formulations cleared from the nasal cavity were 70% for lactose, 58% for lactose/apomorphine, 24% for Carbopol 971P((R)), 12% for Carbopol 971P((R))/apomorphine, and 27% for carboxymethylcellulose/apomorphine. Apomorphine inhibited nasal mucociliary clearance since migration of the radioactivity administered with apomorphine containing preparations was in all cases slower than that of the corresponding powder without apomorphine. The peak plasma concentration of apomorphine was attained while all the formulations were still within the nasal cavity. The use of mucoadhesive polymers such as Carbopol 971P((R)) or carboxymethylcellulose in nasal dosage forms increases their residence time within the nasal cavity and provides the opportunity for sustained nasal drug delivery.

Topics: Acrylic Resins; Animals; Apomorphine; Carboxymethylcellulose Sodium; Drug Delivery Systems; Male; Mucociliary Clearance; Nasal Mucosa; Polyvinyls; Rabbits; Technetium

The object of our work is to develop mucoadhesive microspheres to be applied into the urinary bladder. In the present study the microspheres were prepared and the release of a model drug after their adhesion to mucosa was evaluated. The microspheres were prepared by solvent evaporation method using Eudragit RL or hydroxypropylcellulose as matrix polymers and one out of five different polymers as mucoadhesives or non-mucoadhesive references. A method for the evaluation of the drug release from microspheres adhered on guinea pig urinary bladder and small intestine mucosa was developed and the influence of the following parameters on this process was followed: mucoadhesion strength of polymeric films, swelling of polymers and the drug release from microspheres. The results showed that the detachment forces were decreasing in the following order: CMCNa > Carbopol 934P > HPC > EE.HCl = PVP/VA. Carbopol swelled to the largest volume among all polymers and the drug release from microspheres was more retarded when Eudragit RL was used as matrix polymer. When comparing the results of pipemidic acid release from microspheres adhered on intestinal mucosa with detachment forces, similar ratios among the mucoadhesive polymers can be seen. On the other hand, differences between two mucosae were observed. These differences are due to the amount of mucus on mucosa and might also be influenced by the charge of mucus. The goal of our work at this point of investigation was achieved by microspheres containing carboxymethylcellulose as mucoadhesive and Eudragit RL as matrix polymer because they provide the longest release time from microspheres adhered on vesical mucosa and sufficient high strength of mucoadhesion.

Topics: Acrylic Resins; Animals; Carboxymethylcellulose Sodium; Cellulose; Chemistry, Pharmaceutical; Guinea Pigs; In Vitro Techniques; Intestinal Mucosa; Intestine, Small; Male; Microspheres; Organ Specificity; Polymers; Polyvinyls; Tissue Adhesions; Urinary Bladder

Controlled release buccal patches were fabricated using Eudragit NE40D and studied. Various bioadhesive polymers, namely hydroxypropylmethyl cellulose, sodium carboxymethyl cellulose and Carbopol of different grades, were incorporated into the patches, to modify their bioadhesive properties as well as the rate of drug release, using metoprolol tartrate as the model drug. The in-vitro drug release was determined using the USP 23 dissolution test apparatus 5 with slight modification, while the bioadhesive properties were evaluated using texture analyzer equipment with chicken pouch as the model tissue. The incorporation of hydrophilic polymers was found to affect the drug release as well as enhance the bioadhesiveness. Although high viscosity polymers can enhance the bioadhesiveness of the patches, they also tend to cause non-homogeneous distribution of the polymers and drug, resulting in non-predictable drug-release rates. Of the various bioadhesive polymers studied, Cekol 700 appeared to be most satisfactory in terms of modifying the drug release and enhancement of the bioadhesive properties.

Topics: Acrylic Resins; Adhesiveness; Administration, Topical; Animals; Carboxymethylcellulose Sodium; Chickens; Delayed-Action Preparations; Drug Delivery Systems; Drug Design; In Vitro Techniques; Lactose; Methylcellulose; Models, Biological; Mouth Mucosa; Oxazines; Polymers; Polyvinyls; Solubility; Viscosity

To evaluate the additional effect of bioadhesives in combination with iotrolan and barium as oral contrast media in an animal model.. The bioadhesives Noveon, CMC, Tylose and Carbopol 934 were added to iotrolan and barium. The solutions were administered to rabbits by a feeding tube. The animals were investigated by computed tomography (CT) and radiography after 0.5, 4, 12, 24 and in part after 48 hours. Mucosal coating and contrast filling of the bowel were evaluated.. Addition of bioadhesives to oral contrast media effected long-term contrast in the small intestine and colon, but no improvement in continuous filling and coating of the gastrointestinal tract was detected. Mucosal coating was seen only in short regions of the caecum and small intestine. In CT the best results for coating were observed with tylose and CMC, in radiography additionally with carbopol and noveon. All contrast medium were well tolerated.. The evaluated contrast medium solutions with bioadhesives have shown long-term contrast but no improvement in coating in comparison to conventional oral contrast media.

Topics: Acrylic Resins; Adhesiveness; Adhesives; Administration, Oral; Animals; Barium Sulfate; Carboxymethylcellulose Sodium; Contrast Media; Digestive System; Drug Carriers; Drug Evaluation; Gels; Methylcellulose; Pharmaceutic Aids; Polyvinyls; Rabbits; Tomography, X-Ray Computed; Triiodobenzoic Acids

Bioadhesion could significantly improve oral therapeutics for periodontal diseases and mucosal lesions. This project was designed to examine the factors important to prolonged adhesion (adhesion time) in organ culture under standardized conditions. A wide variety of bioadhesives were tested in the model and the effect of mucin was also examined. Whilst many gels adhered for 1-5 h, others (chitosan and Eudispert) showed no retention loss over 4 d. Histologically, chitosan also showed excellent tissue wetting properties. For most materials, however, mucin significantly reduced adhesion times (P < 0.05). In conclusion, the absence of mucin, the control of gel hydration and swelling, and wetting characteristics were identified as key factors for prolonged adhesion.

Topics: Acrylic Resins; Adhesives; Administration, Buccal; Analysis of Variance; Animals; Carboxymethylcellulose Sodium; Cheek; Chitin; Chitosan; Cricetinae; Culture Techniques; Drug Carriers; Drug Delivery Systems; Gels; Hemostatics; Mouth Mucosa; Mucins; Periodontium; Polyethylene Glycols; Polymethacrylic Acids; Polysaccharides, Bacterial; Polyvinyls; Tissue Adhesions