A figure of natural gums and mucilages are available to explicate conventional and fresh drug bringing systems. These substances are widely used to explicate assorted dose signifiers because of their less cost, ready handiness, nontoxic, capable of chemical alteration, produces comforting action, non thorn, biodegradable and biocompatible. Assorted research workers were besides used these natural substances to explicate bioadhesive drug bringing systems particularly for buccal, stomachic, enteric, ophthalmic, rhinal and transdermic paths of drug disposal to better patient conformity and bioavailability of active medicine.
Hence, the present probes were chiefly focused on isolation and word picture of natural mucoadhesive agents in line of fixing mucoadhesive tablet of Clopidogrel bisulphate to bring forth stomachic keeping and better bioavailability through unwritten path. Natural substances were isolated from assorted works parts like seed, root and fruit. Prosopis juliflora seed, Abelmoschus esculentus root, Ocimum americanum seed, Bauhinia racemosa seed, Zizisphus mauritiana fruit, Cassia auriculata seed and Cordia myxa fruit were selected on the footing that they were possess abundant measure of mucilage. Mucilages are utile to develop mucoadhesive bringing systems93.
Water was used as an economic extraction medium ( dissolver ) to insulate the mucoadhesive agent from selected works parts. Warm H2O was found helpful to fix the puffiness of seeds. Isolated mucoadhesive agents were swelled in H2O medium and were produced syrupy colloidal scatterings and gel. Acetone was found utile to precipitate and sublimate the mucoadhesive agent. It confirms all stray mucoadhesive agents were hydrophilic in nature. More than 10 % mucoadhesive agent was obtained from Prosopis juliflora seeds and Ocimum americanum seeds.
Ruthenium ruddy trial ( mucilage ) , Fehling & A ; acirc ; ˆ™s trial ( saccharide ) , Molisch ‘s Test ( cut downing sugar ) , Ninhydrin trial ( aminic acids ) , Test with Iodine ( amylum ) , Biuret trial ( protein ) , Salkowski trial ( steroid ) , Baljet & A ; acirc ; ˆ™s trial ( glycoside ) , Shinoda trial ( flavonoids ) , Wagners test ( alkaloids ) , trial with acetic acid solution ( tannic acids and phenolic compounds ) , are utile to place chemical belongingss of stray mucoadhesive agents122. Mucilage, saccharide and cut downing sugar were present in all stray natural mucoadhesive agents. Amino acid, proteins were besides present in some mucoadhesive agents. Mucilages, saccharides, cut downing sugars, aminic acids and proteins may incorporate hydroxyl, amino and carboxyl functional groups in their construction.
Pharmaceutical excipient bring forthing stable syrupy solutions at assorted pH are utile in planing sustained or controlled release bringing, gel, transdermic drug bringing systems. It was observed that mucoadhesive agents isolated from Prosopis juliflora seed and Abelmoschus esculentus root were shown stable viscousness in distilled H2O and 0.1 N HCl ( pH 1.2 ) . Other mucoadhesive agents were shown reduced viscousness towards acidic pH. Instability of syrupy nature of natural mucoadhesive agent with alteration in pH may impact the mucoadhesive and drug release belongings. It is besides apparent that mucilage obtained from Opuntia Ficus shows increased viscousness with alteration in pH from acidic to basic153. Besides viscousness of guar gum remains unaffected with alteration in pH154.
Swelling is cardinal mechanism of drug diffusion in controlled release formulation155. It is prerequisite for mucoadhesion through wetting, uncoiling and distributing of polymer over mucosal surface. It is utile produce mucus-mucoadhesive confidant contact and so to organize mucoadhesive bond156. Mucoadhesive agent isolated from Prosopis juliflora seed and Abelmoschus esculentus root were shown about equal swelling index in H2O and in 0.1 N HCl while others were affected. Swelling is related to hydration. Overhydration produces slippy mucilage and therefore affects mucoadhesion157. High swelling belongings of excipient is of import in binding, gelling, mucoadhesion and matrix formation. Optimum puffiness of mucoadhesive agent controls drug release by keeping matrix structure158.
In acidic medium, decreased swelling index with increased clip indicates lessening in hydration of mucoadhesive agents due to hydrolysis which may affects drug release and mucoadhesion property159. Sing the nervous pH of natural mucoadhesive agents, they were utile for unwritten usage as they may non annoy to unwritten mucous membrane. These were incorporating less than 5 % wet content. Low wet content in excipient suggests its suitableness in preparations incorporating wet sensitive drugs. Presence of high measure of wet leads microbic growing, subsequent debasement and shelf life of product160.
As the natural mucoadhesive agents were produced hapless flow in Carr & A ; acirc ; ˆ™s squeezability index and angle of repose method, they needs wet granulation to explicate tablet dose signifier. Bulk denseness and tapped denseness revels packing agreement and compression profile of substance. Natural mucoadhesive agents were holding presence of interparticle porousness and compaction161.
The residue staying left after incineration of the rough drug is referred as ash value. Residue contains inorganic stuffs like Ca oxalate, carbonates, phosphates, silicates and silica124. Natural mucoadhesive agents were shown low degrees of entire ash value and acid indissoluble ash value. It revel that they contains really little measure of inorganic stuffs and contaminations present and besides would be suited for unwritten disposal.
Natural mucoadhesive agents and Carbopol 934P ( Synthetic polymer ) were meticulously investigated for in vitro mucoadhesion survey utilizing Wihelmy & A ; acirc ; ˆ™s method, falling sphere method, shear emphasis method, spring balance method, modified physical balance method and keeping clip method. All these methods were selected by sing the stomachic conditions like pH of stomachic fluid, stomachic mucous membrane and mucous secretion secreted from stomachic mucous membrane. Gastric keeping of mucoadhesive agent was determined by in vivo ( X- beam ) method utilizing coneies.