Carbopol Research Articles

FORMULATION AND EVALUATION OF MUCOADHESIVE BUCCAL TABLET OF DOMPERIDONE MALEATE

The objective of the present study was to develop and evaluate mucoadhesive dosage form of Domperidone maleate. It is an antiemetic synthetic benzimidazole compound that acts as a dopamine D2 receptor antagonist. Mucoadhesive Domperidone maleate tablet formulation was prepared by direct compression method. The formulation F3 containing (Carbopol 940 + sodium alginate) was found to be best among all the formulation batches because of its consistent release rate for 7 h and extent of drug release was 94.44%. Graphical treatment of the formulation F3 to Higuchi’s equation showed that the drug release was diffusion mediated. In-vitro permeability study for formulation F3 for 7 h had shown 76.69% drug release. FTIR studies showed no evidence on interaction between drug and polymers. Key words: Domperidone maleate, Mucoadhesive tablet, antiemetic

Floating bioadhesive matrix tablets of ondansetron HCl: Optimization of hydrophilic polymer‑blends

The work investigates the development and optimization of floating bioadhesive matrix tablets of ondansetron HCl for gastroretentive delivery using 23 factorial design. The effects of xanthan gum, guar gum, carbopol 934 P as hydrophilic polymer‑blends on drug release were analyzed. The optimized tablets were floated well in simulated gastric fluid (SGF) (>8 h) with no lag‑time and also showed a good bioadhesion time (5.23 ± 0.25 min) on goat intestinal mucosa in SGF. The in vitro drug release of these tablets showed sustained ondansetron HCl release over 8 h, which correlated well with controlled‑release (zero order) pattern with super case‑II transport mechanism. Key words: Bioadhesion, floatation, gastroretention, matrix tablets, ondansetron HCl, polymer‑blend

Permeation of indomethacin from semisolid preparations through various semipermeable membranes

Objective: The aim of this study was to evaluate and compare the permeation of model drug indomethacin (IND) from various types of gels through several semipermeable membranes.Methods: Permeation of IND from gels based on carbomer (CA), hydroxyethylcellulose (HEC), and polyacrylamid/laureth-7/isoparaffin was performed via diffusion cell method through membranes: shed snake skin, full thickness chicken skin, mucosa of pork small intestine, and cellophane.Results: The least permeation of IND was observed in the case of shed snake skin and full thickness chicken skin. It did not exceed 5.4% of original amount in the preparation after 3 h of measurement regardless the type of gel. In the case of mucosa of pork small intestine and cellophane the permeated amount of IND ranged from 9.4 to 55.4% depending on the type of gelling agent used. There was also quite a significant influence of a gelling agent on the permeation of IND observed. The permeation of IND was highest from CA gel, where it ranged from 0.6 to 52.2% of original amount in the preparation depending on the type of membrane used. Gelling agent inhibiting the permeation the most was HEC, where the permeated amount of IND did not exceed 12.3% regardless the type of membrane used.Conclusions: In general the permeated amount of IND through biological membranes containing stratum corneum represented just a small part of the amount in original preparation. Gelling agent has significant effect on the extent and rate of permeation.

Development of low methoxy amidated pectin-based mucoadhesive patches for buccal delivery of triclosan: Effect of cyclodextrin complexation

A novel mucoadhesive buccal patch formulation of triclosan (TR), a broad spectrum antibacterial agent, was developed using low methoxy amidated pectin (AMP). The integrity of AMP matrix was improved by addition of 20% (w/w) Carbopol (CAR). The efficiency of β-cyclodextrin-epichlorohydrin polymer (EPIβCD) and anionic carboxymethylated β-cyclodextrin-epichlorohydrin polymer (CMEPIβCD) in optimization of TR solubility and release from such a matrix was investigated and confronted to that of parent β-cyclodextrin (βCD). Loading of TR/βCD co-ground complex into AMP/CAR matrix resulted in a biphasic release profile which was sensitive upon the hydration degree of the matrix, due to lower solubilizing efficiency of βCD, while the drug release from patches loaded with TR/EPIβCD complex was significantly faster with a constant release rate. Microbiological studies evidenced faster onset and more pronounced antibacterial action of TR/EPIβCD loaded patches, clearly demonstrating their good therapeutic potential in eradication of Streptococcus mutans, a cariogenic bacteria, from the oral cavity.

FORMULATION AND CHARACTERIZATION OF GASTRORETENTIVE MUCOADHESIVE QUETIAPINE FUMARATE TABLETS

Background and the purpose of the study: Development of gastroretentive delivery system is one of novel approach in oral route of drug administration. Prolonging the gastric retention time is desirable for achieving greater therapeutic benefit of drug substance. The research was aimed to develop gastroretentive mucoadhesive tablets of quetiapine for prolonged residence time. Methods: The wet granulation method was used for the preparation of various formulations (F1-F12) using different mucoadhesive polymers viz. hydroxyl propyl methyl cellulose K4M, hydroxyl propyl cellulose, chitosan, carbopol 934P and sodium carboxy methyl cellulose in different combinations. The formulations were subjected to various evaluation parameters such as swelling index, mucoadhesive strength, in vitro drug release profile and physical properties. Results: The study showed that the formulation containing chitosan and carbopol 934P in combination (F7) exhibited good swelling index, high mucoadhesive strength of 192.66 g and maximum in vitro residence time (10.14 hrs) and in vitro cumulative drug release after 24 hrs (96.26%). The optimized formulation (F7) was further subjected to in vivo retention time determination in rabbit by X-ray technique and accelerated stability studies. Conclusion: The formulation (F7) had shown promising potential to achieve desired goal as depicted from the release studies, swelling studies & mucoadhesion studies.

Evaluation of base for optimal drug delivery for iontophoretic therapy: Investigation of quality and stability

Increasing the penetration rates of active substances from transdermal preparations to skin is a major goal for the pharmacy technologists. Higher concentration of the active substance in the skin is commonly associated with higher treatment quality. The aim of this study was to model an optimal pharmaceutical iontophoretic delivery form and to examine the dependency of its quality and stability on different parameters (that is, polymer type and concentration used for formulation, the viscosity of the vehicle, and its electrical conductivity). Gels have been intended to be used for 5-aminolevulinic acid (5-ALA) incorporation. The optimization of the vehicles has been performed without 5-ALA insertion due to its high price and very large standard concentration according to dermatologic protocols; but the gels have been evaluated accordingly to 5-ALA chemical properties. Different concentrations (0.25 to 10%) of four polymers (carbopol (CP), methylcellulose (MC), hypromellose (HM), and hydroxypropylcellulose (HPC)) have been selected for the formulations, and they produced wide range of dynamic viscosity (1.5 to 10000 mPa×cm). The highest shear viscosity has been measured in CP gels; dynamic viscosity was the highest in MC gels. 1000 to 5000 mPa×s was identified as the optimal dynamic viscosity for the iontophoretic gels. The following polymer concentrations have been singled out as optimal ones: 1% for carbopol, 4% for methylcellulose, and 3% for hypromellose. PH values of 5 and 7 have been identified as the most suitable for 5-ALA incorporation. Key words: Gel, iontophoresis, viscosity, conductivity, rheology.

Enhanced oral bioavailability of novel mucoadhesive pellets containing valsartan prepared by a dry powder-coating technique

The aim of this study was to develop novel mucoadhesive pellets containing valsartan (VAL) with enhanced oral bioavailability. Two types of VAL loaded core pellets were prepared by an extrusion/spheronization method, and further dry-coated with a mixture of hydroxypropylmethylcellulose (HPMC) and carbomer (CB) at different ratios. The effects of the pellet core composition, HPMC:CB ratio and coating level on the drug release from the coated pellets were investigated. The physicochemical properties of the core and coated pellets were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FT-IR). In addition, the in vitro and in vivo mucoadhesion properties as well as the bioavailability of the coated pellets in rats were evaluated by using VAL suspension and core pellets as control preparations. The results of the release study demonstrated that the two types of core pellets, especially the pellets formulated with a solubilizer and a pH modulator gave considerably faster drug release than the VAL powder. However, the core and coated pellets exhibited similar release profiles indicating that the dry powder-coating did not retard the drug release. Strong molecular interactions were observed between the drug and the carriers in FT-IR analysis. The coated pellets displayed distinct mucoadhesive property in vitro and delayed gastrointestinal (GI) transit in vivo. Furthermore, the coated pellets exhibit significantly higher AUC0–12h and Cmax, as compared to the core pellets and drug suspension. It was concluded that the mucoadhesive pellets could render poorly water soluble drugs like VAL with a rapid drug release, delayed GI transit and enhanced oral bioavailability.

Studies of pilocarpine:carbomer intermolecular interactions

The interactions between pilocarpine (PIL) and the anionic polyelectrolyte carbomer (CBR) were investigated. The effects of the chemical interactions on the chemical stability of the drug also were evaluated. The binary system was characterized by nuclear magnetic resonance techniques, Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction, scanning electron microscopy (SEM) and thermal analysis. The experiments showed that the complex, prepared by freeze-drying, is a solid amorphous form different from its precursors, thereby offering an interesting alternative for the preparation of extended release matrices. The solution stability of PIL was studied at pH 7 and 8, at 70°C. The PIL solution stability was evaluated alone and in the presence of CBR. Results indicated that the drug in the presence of the polymer is 3.3 and 3.5 times more stable, at pH 7 and pH 8, respectively, than the drug without CBR. The activation energy and the frequency factor, according to Arrhenius plot, were estimated to be 13.9±0.4 and 14.8±0.5kcalmol−1, and 6.1±0.3 and 7.6±0.3, with and without the polymer, respectively.

Design, evaluation and in vitro - in vivo correlation of glibenclamide buccoadhesive films

Background:Glibenclamide (G) is a popular anti-diabetic drug, belonging to the class of sulfonylurea. The drug is widely used for treating type II diabetes but it undergoes first-pass effect. A novel aspiration in treatment of diabetes, to provide greater therapeutic effect, bypass first pass effect and to improve patient compliance upon administering buccal drug delivery of Glibenclamide (G) have not been tested literally. Hence, the present study was designed to develop the buccal mucoadhesive films of glibenclamide by solvent casting technique; that is by using different polymers such as Hydroxy Propyl Methyl Cellulose 15 cps (HPMC), carbopol (CP), and poly vinyl pyrrolidone. Propylene glycol, which served the purpose of plasticizer as well as penetration enhancer and the backing membrane used was aluminium foil.Materials and Methods:The films were subjected to physicochemical parameters, in-vitro drug release and ex vivo bucco adhesive strength.Results:The satisfactory results were obtained in all prepared formulation and based on the results G14 [HPMC (150 mg) + CP(20 mg) + PVP (30 mg)] was the best one compared to others. The drug release of all formulation follows zero order kinetics by diffusion mechanism of non-fickian diffusion type. Ex vivo, buccal permeation studies by using sheep buccal mucosa and finally stability studies by using human saliva were carried out for the optimized formulation G14.Good correlation was observed between in-vitro and in vivo correlation, thus revealing the ability of the formulation to reproduce the in-vitro release pattern through the in vivo.Conclusion:Glibenclamide muck-adhesive buccal films could be promising one as they, increase bioavailability by bypassing the first pass effect, minimize the dose, reduces the side effects, and improve patient compliance and also glibenclamide might be a right and suitable candidate for oral controlled drug delivery via buccoadhesive films.

Formulation and Evaluation of Nifedipine Gel

Gels for transdermal drug delivery of nifedipine were formulated using various solvents, co-solvents in a carbomer gel base. These medicated gels were then assessed for physico-chemical properties and invitro release studies through artificial semi-permeable membrane using Keshary Chien diffusion Cell. Selected optimal formulations were further subjected to primary skin irritation studies and later on stability studies. Due to the photosensitive nature of nifedipine, all experimental works were carried out in dark.

Rheological Evaluation of Polyacrylic Acid Hydrogels

A range of recently introduced polyacrylic acid gel systems (Noveon AA-1, Carbopol 974P, Carbopol EX-214) and Carbopol 934 have been examined rheologically using continuous shear, creep and oscillatory measurements. Continuous shear measurements indicated that Carbopol 934 gels have the highest viscosity, with a low degree of thixotropy, while sodium-neutralized Carbopols 974P and EX-214 gels showed differences in rheological behaviour, despite being theoretically identical in structure. Creep and oscillatory studies indicated that Carbopol 934 had the highest degree of gel network elasticity, followed by Noveon AA-1, Carbopol 974P and Carbopol EX-214.

Influence of Sanchi gel on TIMP-1 and MMP-1 expression in epidural adhesion

Objective To explore the effects of Sanchi gel on MMP-1 and TIMP-1 expression in epidural adhesion after laminectomy. Methods Laminectomy model was set up in SD rats. 72 SD model rats were divided randomly into Saline group, Zhanlp group, Carbopol Gel group and Sanchi Gel group, with 18 rats in each group. On 7, 14 and 21 days after the laminectomy, immunohistochemistry (method of S-P) was adopted to detect the expression of TIMP-1 and MMP-1. Results Different treatments had different influence on TIMP-1 and MMP-1 expression in epidural adhesion. The expression of TIMP-1 increased gradually on 14 dand 21 d after operation, and Sanqi Gel group showed weaker expression than the other groups (P＜0.05), but the number of positive cells decreased gradually. As to the expression of MMP-1, there was no difference among each group at the end of the second week (P＞0.05). There was a difference between Sanchi Gel group and the other groups at the end of third week (21 d) (P＜0.05) after operation. Sanchi Gel group showed higher expression of TIMP-1 than the other groups. The number of positive cells sharply decreased from 14 d to 21 d after operation. Conclusion Sanchi Gel has a significant preventive effect on fibrous scar formation after laminectomy. The possible mechanism of preventing epidural adhesion after laminectomy by Sanchi Gel could be its regulating and controlling the expression of TIMP-1 and MMP-1 in epidural tissue. Key words: Sanchi Gel; Adhesion; Laminectomy; Inhibitor of metalloproteinase-1 ; Matrix metalloproteinase- 1

In vitro and in vivo evaluation of WGA–carbopol modified liposomes as carriers for oral peptide delivery

Surface modification of liposomal nanocarriers with a novel polymer–lectin conjugate was proposed for enhancing the systemic uptake of encapsulated peptide and protein therapeutics after oral administration. Wheat germ agglutinin (WGA) was covalently attached to carbopol (CP) using the carbodiimide method. The prepared WGA–CP conjugate retained the biological cell binding activity of WGA without any evidence of cytotoxicity to Caco-2 monolayers. Cationic liposomes in the size range of 100nm were prepared by the lipid film hydration method followed by probe sonication and surface modification with negatively charged WGA–CP. The uptake of WGA–CP liposomes by Caco-2 cells was significantly higher than that of non-modified or CP liposomes. The uptake was dependent on the surface concentration of WGA, temperature, and incubation period and was significantly inhibited in the presence of chlorpromazine and 10-fold excess of free WGA. These results suggest the involvement of active transport mechanism for the cellular uptake of the modified liposomes, mediated mainly by binding of WGA to its specific cell membrane receptors. Dual channel confocal microscopy confirmed the simultaneous association and internalization of the polymer conjugate and the liposomal carrier by Caco-2 cells and intestinal membrane of rats. In addition, the pharmacological efficacy of calcitonin, a model peptide drug, was enhanced by more than 20- and 3-fold following peroral administration of calcitonin-loaded WGA–CP liposomes when compared to non-modified and CP liposomes, respectively.

Protective effects of estrogen on chronic ocular hypertension-related rabbit retinal damages

Objective To investigate the protective effects of estrogen on rabbit retinal damages induced by chronic ocular hypertension. Methods A total of 18 white New Zealand female rabbits were randomly divided into ovariectomized (OV) group and sham OV (SOV) group. Bilateral ovaries were remove in OV group while only the adipose tissue around ovarian were remove in SOV group. Chronic ocular hypertension was induced by anterior chamber injection of carbomer. Retinal cell apoptosis was measured by terminal deoxynucteotidyl transferase-mediated dUTP nick end labeling (TUNEL), the expression of bcl-2,bax were detected by immunohistochemistry. The images were captured under microscope and analyzed with computer-image-analysis system. Results Four, six and eight weeks after ocular hypertension modeling,the OV retinas have less retinal ganglion cells, thinner optic nerve fiber layer and inner nuclear layer and more TUNEL positive cells (t = 3. 285, 4. 012, 3. 624; P< 0.01). The OV retinas also have less bcl-2 expression (t=4. 256,3. 867,3. 459;P<0. 01), more bax positive cells (t=3. 211,3. 625,3. 253;P<0. 01).Bcl-2 expression was negatively correlated with TUNEL positive cells indicating bcl-2 can inhibit apoptosis.Bax expression was positively correlated with TUNEL positive cells indicating bax induce apoptosis.Conclusion Estrogen has a neuroprotection role to rabbit retina under chronic ocular hypertension by reducing apoptosis. Key words: Estrogens/physiology; Retinal ganglion cells; Apoptosis; Bcl-2-associated X protein; Animal experimentation

Influence of various concentrations of terpene-4-ol enhancer and carbopol-934 mucoadhesive upon the in vitro ocular transport and the in vivo intraocular pressure lowering effects of dorzolamide ophthalmic formulations using albino rabbits

The objectives of the current study are (i) to maximize the ocular bioavailability of dorzolamide hydrochloride (DZD) through; (a) enhancement of the DZD corneal transport using various concentrations of selected natural terpene-4-ol enhancers, (b) increasing the contact time of the drug with the absorbing tissues of the eye using selected carbopol-934 (C-934) as mucoadhesive to reduce the extensive pre-corneal loss of the installed dose due to the physiologically normal fast tear-washout, and (ii) to assess the in vivo intraocular pressure (IOP) lowering effects of the gel test formulations using normotensive New Zealand albino rabbits. In this study, DZD was formulated as 2% formulations ophthalmic gels containing different concentrations of C-934 as mucoadhesive, as well as, with various concentrations of terpene-4-ol as a natural corneal penetration enhancers. The transport of DZD from the gel formulations was quantitatively determined using in vitro diffusion experiments. The permeability parameters of DZD were calculated employing the most appropriate mathematical equations. Further, the in vivo IOP lowering effects of the test formulations were also assessed using the TONO-PEN®XL applanation tonometer in normotensive New Zealand albino rabbits. The overall results revealed that there is a direct correlation between both the in vitro permeability parameters and the contact period with the ocular tissues and the in vivo ΔIOP. In such case, the in vitro permeability parameters of DZD could be used as a determinant for the in vivo IOP measurements. The magnitude of the DZD-IOP lowering effects as well as the durations of actions for the test formulations has been found to be greatly dependent upon (a) the concentration of the terpene-4-ol corneal penetration enhancer and (b) the duration of contact period with the ocular tissues, which was found to be a single-valued function of the C-943 mucoadhesive concentration. © 2009 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 99:119–127, 2010

FORMULASI GEL MINYAK KAYU MANIS (Oleum Cinnamomi) SEBAGAI PEMBERSIH TANGAN MENGGUNAKAN VARIASI KONSENTRASI CARBOPOL

As investigation has been done on cinnamomi oil gel formulation as hand clean use ca rbopol gel bases. The aim of the investigation was to select the most stable formula if cinnamomi oil through stability evaluation which done by organoleptic observation, viscosity and yield value determination. It was made three formula with several different concentration carbopol in this investigation that are 0,3 %, 0,4 % and 0,5 %. Of the result organoleptic observation there was no alternation before and after stress condition. Result statistic analyse on viscosity data shown that there was an influence of gel formula to viscosity before and after stress condition. At formula I and III shown that there was a very real influence between of before and after stress condition, while at formula II shown that there was no real influence. Result statistic analyse on yield value data shown that there was an influence of gel formula to yield value before and after stress condition. At formula I shown that there was a real influence between of before and after stress condition, at formula III shown that there was a very real influence between of before and after stress condition, while at formula II shown that there was no real influence. The conclution was formula II have the most optimal stability use concentration of carbopol 0,4 %. Key Words : Oleum Cinnamomi, Hand Clean, Carbopol

FORMULASI GEL MINYAK KAYU MANIS (Oleum Cinnamomi) SEBAGAI PEMBERSIH TANGAN MENGGUNAKAN VARIASI KONSENTRASI CARBOPOL

As investigation has been done on cinnamomi oil gel formulation as hand clean use ca rbopol gel bases. The aim of the investigation was to select the most stable formula if cinnamomi oil through stability evaluation which done by organoleptic observation, viscosity and yield value determination. It was made three formula with several different concentration carbopol in this investigation that are 0,3 %, 0,4 % and 0,5 %. Of the result organoleptic observation there was no alternation before and after stress condition. Result statistic analyse on viscosity data shown that there was an influence of gel formula to viscosity before and after stress condition. At formula I and III shown that there was a very real influence between of before and after stress condition, while at formula II shown that there was no real influence. Result statistic analyse on yield value data shown that there was an influence of gel formula to yield value before and after stress condition. At formula I shown that there was a real influence between of before and after stress condition, at formula III shown that there was a very real influence between of before and after stress condition, while at formula II shown that there was no real influence. The conclution was formula II have the most optimal stability use concentration of carbopol 0,4 %. Key Words : Oleum Cinnamomi, Hand Clean, Carbopol

Mussel-inspired fabrication of structurally stable chitosan/polyacrylonitrile composite membrane for pervaporation dehydration

The structural stability of chitosan (CS)/polyacrylonitrile (PAN) composite membrane for pervaporation dehydration was improved by the introduction of mussel-adhesive-mimetic molecule, carbopol (CP). The composite membranes were simply fabricated by layer-by-layer technique, in which CP as an intermediate layer bridging the CS active layer and the PAN support layer. The structure and morphology of composite membranes were characterized by Fourier transform infrared spectroscopy (FT-IR) and field emission scanning electron microscope (FESEM). The methylene iodide contact angle measurement, T-peel test and molecular dynamics (MD) simulation were employed to analyze the wetting characteristics, adhesion strength and interaction at the interface. Positron annihilation lifetime spectroscopy (PALS) was employed to probe the fractional free-volume properties of the CS active layer. The membrane pervaporation performance was investigated by varying the molecular weight (CP981, 940, 974) and concentration of CP as well as the cross-linking degree of the CS active layer. When the concentration of CP974 was 0.5 wt.%, GCCS(60)/CP(0.5)/PAN composite membrane displayed the permeation flux of 1247 g/(m 2 h) and separation factor of 256 for ethanol dehydration at 353 K. Furthermore, the enhancement of the long-term operation stability of membrane by incorporating the CP layer was also verified.

Changes of structures of anterior chamber angle in rabbit chronic high intraocular pressure model

To observe the anterior chamber angle changes occurred in compound Carbomer-induced chronic high intraocular pressure (IOP) model in rabbit eyes. It was an experimental study. Thirty two rabbits were randomly divided into eight groups. Compound Carbomer (0.3%, 0.3 ml) was injected into the left anterior chamber. A group of rabbits were randomly killed after 1, 2, 3, 4, 6, 8, 10 and 12 weeks. The anterior chamber of the rabbit eye specimens was observed. IOP increased slowly following the application of the drug, high IOP lasted for 3 months. The drug-induced changes of anterior chamber angle consisted of early inflammatory response and late fibrous changes. Inflammatory response occurred in early stage and reduced or disappeared after 3 weeks. Fibrous degeneration and adhesion obstruction occurred in the anterior chamber angle after 4 weeks. Under the electron microscope, the trabecular was expanded and deformed, with hyperplasia of collagen and elastic fibers. Endothelial cells were separated from the trabecular, and showed the morphology of lymphocytes, with the function similar to the macrophages. Phagocytized Carbomer particles were transported through the vacuoles of Schlemm's canal endothelial cells. Large vacuoles gradually reduced. Excessive Carbomer particles were accumulated in the endothelial cells and obstructed the Schlemm's canal. This induced the fibrous proliferation and the destruction of anterior chamber angle structures. The obstruction of aqueous humor outflow induced by compound Carbomer in rabbit high IOP model is caused mainly by the changes in trabecular endothelial cells.

FORMULATION AND EVALUATION OF A BUCCOADHESIVE CAPTOPRIL TABLETS

Buccoadhesive tablets of captopril were prepared by directcompression of the drug with different polymers; Carbopol 934 (CP934), Eudragit RS 100 (EU RS 100), Chitosan (Ch), Hydroxpropylmethylcellulose (HPMC) and Polyvinylpyrrolidone K30 (PVP K30)either singly or in blends of different ratios. The tablets wereevaluated for their weight variation, drug content uniformity,friability, hardness, swelling index, surface pH, in-vitrobioadhesive strength and release characteristics. Thebioavailability and the pharmacokinetics parameters of captoprilfrom two selected formulations (CP 934:HPMC 6:4 and Ch:HPMC6:4) were evaluated.The in-vitro bioadhesive strength and release characteristicswere found to be a function of the type of polymer and ratio ofpolymer blends. Swelling and bioadhesive characteristics weredetermined for both plain and medicated tablets. The highconcentration of carbopol and chitosan containing formulationsshowed the greatest adhesive strength. The mean pharmacokineticparameters of captopril after buccoadhesive tablet administrationwere: Cmax 506.9 ng/ml, Tmax 4 hr, AUC0-8 2359.5 ng.hr/ml for CP934: HPMC (6:4), while Cmax 429.02 ng/ml, Tmax 2.67 hr, AUC0-81637.43 ng.hr/ml for Chitosan: HPMC (6:4). In comparison, incase of oral administration of control tablet the Cmax 591.28 ng/ml,Tmax 1.5 hr, AUC0-8 1869.29 ng.hr/ml.