Hydroxyl Propyl Methyl Cellulose K4M Research Articles

Effect of hydrophilic polymer and binder on drug release of metformin HCl sustained release tablet

To develop an oral sustained release Metformin HCl tablet by wet granulation technique, using different grades of hydroxyl propyl methylcellulose (HPMC) in different concentration and by varying binder concentrations. Metformin HCl was received as gift sample while all other excipients of analytical grade were procured from the market. Formulation optimization was done by three ways to select optimum formula for preparing sustained release matrix tablet. Trail batches were prepared by altering the hydrophilic polymers as well as binder concentration and all the batches are evaluated for pre-compression and post-compression parameters. In first step, concentration of HPMC K4M is optimized by preparing three trial batches while in second step and third step concentration of HPMC K15M and HPMC K100M is optimized by next three-three batches respectively. Amount of HPMC is optimized to 240mg. The drug release of all the optimized HPMC batches were evaluated for in-vitro drug release study in pH 6.8 phosphate buffer solution in comparison with marketed formulation. Drug identification was performed by melting point determination, FTIR, UV and solubility determination. After pre-compression and post-compression evaluation we get the appropriate result in B3, B6 and B9 batches.

Formulations of sustained release matrix tablets of Furosemide using natural and synthetic polymers

The primary benefit of a sustained release dosage form compared to a conventional dosage form, is the consistent drug plasma concentration and consequently uniform therapeutic effect. Matrix system are preferential because of their ease, patient compliance etc, than traditional drug delivery which have several drawbacks like reiterated administration, variation in blood concentration level etc. The aim of the present research study was to develop and evaluate sustained release matrix tablets of furosemide using direct compression method using natural gummy and waxy materials (Xanthan gum, bees wax) and synthetic polymers (HPMC K4M). The matrix tablet formulations were prepared by using different drug: polymer ratios (1:1, 1:2 and 1:3). All formulations were assessed using micromeritics studies of powder blend and diverse physicochemical tests. All the physicochemical characters of the formulated tablets were within acceptable limits. The release pattern of the drug was viewed over a period of 12 hours and determined the amount of drug by the UV-Visible spectroscopic method. Dissolution data demonstrated that the formulated tablets with Xanthan gum and hydroxyl propyl methylcellulose (HPMC) provided sustained release of the drug up to 12 hrs. Therefore inexpensively it may be appropriate for the pharmaceutical industries to employ this kind of simple technologies for the expansion of advanced formulations. Hence, we conclude that the purpose of this study was to formulate a sustained release matrix tablet of furosemide using diverse polymers and their dissimilar proportions have been attained.
 Keywords: Furosemide, Direct compression, Natural, Synthetic polymers, Sustained release tablets.

DESIGN AND CHARACTERIZATION OF OROSLIPPERY BUOYANT TABLETS FOR RANITIDINE HYDROCHLORIDE

Objective: The goal behind of performing this study was to come out with an oroslippery buoyant ranitidine hydrochloride tablet to ease the swallowing process. Hence, the drug is released controllably in the stomach regardless of the effect on gastric emptying time.Materials and Methods: The core of the buoyant containing 150 mg of the drug was compressed directly, and sodium bicarbonate was employed as an effervescent agent, besides, hydroxyl propyl methyl cellulose (HPMC) polymer was utilized in different grades in the formulation process. The prepared core was immersed in the coating dispersion, which was formulated using xanthan gum (slipping agent) and Kollicoat instant release (IR) (for film formation). According to the variables in the formulation process, floating properties varies along with the release profile of the drug; therefore, investigation of the effects of variables was conducted, including polymer type and concentration in the core part, and the effect of Kollicoat IR amount as well as the level of coating.Results: According to this study, it was clearly obvious that T4 formulation, that consisted of HPMC K4M, after being dipped 2 times in dispersion of 0.3% xanthan gum and 14% Kollicoat IR, had provided an instant floating, moreover, the in vivo slipperiness was quite acceptable as well as the taste masking. Nevertheless, the percentage of drug release measured after 6 h was 90.15%.Conclusion: The resultant formulas is quite promising to take the lead as new approach to easy swallowing tablets without need of water especially for patients with swallowing problems as well as it is floating tablet that can retain the drug in gastric cavity to be continuously released to ensure its maximum absorption and may improve its bioavailability.

DESIGN AND CHARACTERIZATION OF OROSLIPPERY BUOYANT TABLETS FOR RANITIDINE HYDROCHLORIDE

Objective: The goal behind of performing this study was to come out with an oroslippery buoyant ranitidine hydrochloride tablet to ease the swallowing process. Hence, the drug is released controllably in the stomach regardless of the effect on gastric emptying time.Materials and Methods: The core of the buoyant containing 150 mg of the drug was compressed directly, and sodium bicarbonate was employed as an effervescent agent, besides, hydroxyl propyl methyl cellulose (HPMC) polymer was utilized in different grades in the formulation process. The prepared core was immersed in the coating dispersion, which was formulated using xanthan gum (slipping agent) and Kollicoat instant release (IR) (for film formation). According to the variables in the formulation process, floating properties varies along with the release profile of the drug; therefore, investigation of the effects of variables was conducted, including polymer type and concentration in the core part, and the effect of Kollicoat IR amount as well as the level of coating.Results: According to this study, it was clearly obvious that T4 formulation, that consisted of HPMC K4M, after being dipped 2 times in dispersion of 0.3% xanthan gum and 14% Kollicoat IR, had provided an instant floating, moreover, the in vivo slipperiness was quite acceptable as well as the taste masking. Nevertheless, the percentage of drug release measured after 6 h was 90.15%.Conclusion: The resultant formulas is quite promising to take the lead as new approach to easy swallowing tablets without need of water especially for patients with swallowing problems as well as it is floating tablet that can retain the drug in gastric cavity to be continuously released to ensure its maximum absorption and may improve its bioavailability.

FORMULATION OF RIZATRIPTAN BENZOATE SUBLINGUAL TABLETS PREPARED BY DIRECT COMPRESSION WITH DIFFERENT BIOADHESIVE POLYMER: IN VITRO AND EX VIVO EVALUATION

Objective: The current investigation deals with formulation and evaluation of fast disintegrating sublingual tablets of rizatriptan benzoate (RTB) to produce its intended therapeutic effect for acute treatment of migraine. When the drug is given by sublingual route, it overcomes the first pass metabolism and quick entry of drug in systemic circulation is obtained. It would result in fast pharmacological response hence faster relief from migraine which is an important criterion in migraine therapy.Methods: In this study, RTB sublingual tablets were prepared using direct compression process using various bioadhesive polymers such as sodium carboxymethyl cellulose, hydroxyl propyl methyl cellulose-K4M, and chitosan at various concentration ranging 0.5-5% w/w along with sodium starch glycolate (SSG) or cross carmellose sodium (CCS) as super disintegrants at different concentration ranging 2-8% w/w.Results: The tablets disintegrated quickly and dissolution tests conclude that RTB was released from the formulation within the compendial limits. The formulations batches (A8 and B8) containing 2% w/w chitosan along with 2% w/w SSG or CCS which disintegrate rapidly and show high dissolution and ex vivo permeation were selected as optimized formulations.Conclusion: The results obtained from the study showed that the bioavailability problem of the drug has been solved as the drug is given by sublingual route and it directly enters into systemic circulation. Furthermore, the formulation overcomes the problems associated with migraine attack as fast disintegrating technology is used.

FORMULATION AND EVALUATION OF TRANSDERMAL PATCHES OF ATENOLOL

This study was carried out to develop matrix based transdermal patches containing Atenolol. A 2 factors (HPMC (hydroxyl propyl methyl cellulose) K4M & PVP (Polyvinyl Pyrolidone) 3 level (2 3 ) factorial design was done using Design Expert® which gave 13 experiments. The patches were prepared by Solvent casting method. Propylene glycol (3%) and Tween 80 (6%) were used as plasticizer and permeation enhancer respectively. Physicochemical characteristics and In-Vitro permeation study of formulated transdermal patches were carried out. Contour plot suggested 770 mg of PVP and 265 mg of HPMC K4M in Optimized formulation.

Quality by design approach for development and optimization of Quetiapine Fumarate effervescent floating matrix tablets for improved oral bioavailability

The aim of the investigation was to develop and optimize the effervescent floating matrix tablets of Quetiapine Fumarate (QF) by using 23 factorial design. Amount of hydroxyl propyl methyl cellulose K4M (HPMC K4M (A1)), amount of hydroxyl propyl methyl cellulose K15M (HPMC K15M (A2)) and amount of sodium bicarbonate (A3) (as gas-generating agent) were considered as independent variables and floating lag time (FLT, B1) (sec), percent drug release in 2 h (B2, Q2) and 6 h (B3, Q6) as dependent variables, respectively. Floating tablets of QF were prepared by effervescent technique using direct compression method. Drug-excipient compatibility studies were conducted by using DSC and FTIR techniques. The floating tablets were evaluated for physical characteristics, drug content, swelling index, in vitro buoyancy and in vitro release studies. Optimized formulation contains 25 mg of A1, 12.5 mg of A2 and 25 mg of A3 which resulted in 32 s of B1, 32.89 ± 3.1 % of B2, and 73.61 ± 1.8 % of B3, respectively. DSC and FTIR studies revealed that no interaction between the drug and excipients in the developed formulation. The drug release followed Higuchi model and the Fickian transport. Physico-chemical stability studies revealed that the optimized formulation was stable for 90 days. Based on the physical evaluation and in vitro drug release characteristics, it was concluded that QF was suitable for incorporation into a floating drug delivery system.

Formulation and development of ophthalmic in situ gel for the treatment ocular inflammation and infection using application of quality by design concept

Context: The conventional liquid ophthalmic delivery systems exhibit short pre-corneal residence time and the relative impermeability to the cornea which leads to poor ocular bioavailability.Objective: The aim of this study was to apply quality by design (QbD) for development of dexamethasone sodium phosphate (DSP) and tobramycin sulfate (TS)-loaded thermoresponsive ophthalmic in situ gel containing Poloxamer 407 and hydroxyl propyl methyl cellulose (HPMC) K4M for prolonging the pre-corneal residence time, ocular bioavability and decreases the frequency of administration of dosage form. The material attributes and the critical quality attributes (CQA) of the in situ gel were identified. Central composite design (CCD) was adopted to optimize the formulation.Materials and methods: The ophthalmic in situ forming gels were prepared by cold method. Materials attributes were the amount of Poloxamer 407 and HPMC and CQA identified were Gel strength, mucoadhesive index, gelation temperature and % of drug release of both drug.Results and discussion: Optimized batch (F*) containing 16.75% poloxamer 407 and 0.54% HPMC K4M were exhibited all results in acceptable limits. Compared with the marketed formulation, optimized in situ gel showed delayed Tmax, improved Cmax and AUC in rabbit aqueous humor, suggesting the sustained drug release and better corneal penetration and absorption.Conclusion: According to the study, it could be concluded that DSP and TS would be successfully formulated as in situ gelling mucoadhesive system for the treatment of steroid responsive eye infections with the properties of sustained drug release, prolonged ocular retention and improved corneal penetration.

Formulation of Oral Mucoadhesive Tablets of Pioglitazone using Natural Gum from Seeds of Pithecellobium Dulce


 The plant derived gums and mucilage’s comply with many requirements of pharmaceutical excipients as they are non-toxic, stable, easily available, associated with less regulatory issues as compared to their synthetic counterpart and inexpensive; also these can be easily modified to meet the specific need. The present study was undertaken to isolate mucilage from the seeds of Pithecellobium dulce (P. dulce). The mucilage isolated from P. dulce were used as a bioadhesive polymer in tablet formulation and evaluated for the parameters such as swelling, pH, and bioadhesive property like bioadhesive strength, and ex-vivo residence time. The oral mucoadhesive tablets were prepared using Pioglitazone as model drug and P. dulce seeds mucilage as mucoadhesive polymer. The prepared tablets were evaluated against existing mucoadhesive polymer such as Xanthan gum and Hydroxyl Propyl Methyl Cellulose K4M to explore its use as Pharmaceutical excipients. Swelling index of P. dulce was found to be 87.46 ± 0.11 % which was higher than Xanthan gum but lower than HPMC K4M having swelling index 73.28 ± 0.01 % and 98.88 ± 0.03 % respectively. The results showed that Bioadhesion strength of P. dulce was found to be 50.86 ± 0.03N which was higher than HPMC K4M but lower than Xanthan gum having Force of adhesion 32.81 ± 0.04N and 57.17 ± 0.01N respectively. The percentage cumulative drug release drug release of optimize batch F8 was found to be 101.71 %. So, it was concluded that the mucilage of P. dulce can be used as a pharmaceutical excipient in oral bioadhesive drug delivery systems.

Chick chorioallantoic membrane model for in ovo evaluation of timolol maleate–brimonidine tartrate ocular inserts

The main aspire of this study was to develop ocular drug delivery system for dual drug glaucoma therapy by timolol maleate–brimonidine tartrate and endeavor the possibility of biocompatibility studies by in ova studies. Matrix type, both hydrophilic and lipophilic polymers, and reservoir-type ocular inserts of timolol maleate were prepared using hydrophilic polymers like polyvinyl alcohol, hydroxyl propyl methyl cellulose K4M and lipophilic polymers like ethylcellulose and eudragit S100 and were optimized. Based on the optimized formulation, triple-layered ocular inserts (reservoir type) of dual drug were prepared by solvent casting technique with an objective of reducing the frequency of administration, obtaining controlled release and greater therapeutic efficacy, preservative free dosage form for the treatment of glaucoma. FTIR spectral studies revealed no pharmaceutical incompatibility and no drug polymer interactions. Maximum drug release (99.18 ± 1.7) was achieved when PVP and HPMC K4M in 1:1 ratio with PEG 400 (0.3 ml) drug reservoir layer was sandwiched between ethyl cellulose as rate control membrane up to 32 h in a controlled fashion. Drug release was by non-Fickian diffusion mechanism for single drug formulation. But in dual drug insert, timolol maleate best fit into zero order and for brimonidine tartrate to Higuchi model and diffusion of drugs from this by non-Fickian diffusion mechanism. In ovo studies suggested that the optimized formulation was found to be sterile, biocompatible and physicochemically stable and support us to claim that the developed formulation was biocompatible.

English

Captopril has a short elimination half-life and is stable at pH 1.2 and as the pH increases; the drug becomes unstable and undergoes a degradation reaction. The purpose of this study was to develop a gastroretentive controlled release drug delivery system with swelling and floating properties. Seventeen tablet formulations were designed using hydroxyl propyl methyl cellulose (HPMC) K4M, Carbomer 934, Eudragit RS PO as release retarding polymer(s), lactose or Avicel PH 102 as a filler and sodium bicarbonate as a gas former by direct compression. Tablets were evaluated for various physical parameters, floating properties, swelling ability and drug release characteristics in 12 h. Based on the release kinetics, all formulations best fitted the Higuchi, Hixson Crowell model and non-Fickian as the mechanism of drug release. Statistical analyses of data revealed that formulation containing HPMC K4M (42%, w/w), NaHCO3 (8%, w/w) and Avicel PH 102 (32.35%, w/w) was the promising system exhibiting excellent floating properties and sustained drug release (12 h) characteristics.   Key words: Floating drug delivery system, captopril, HPMC K4M, Carbomer 934, Eudragit RS PO.

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.

Influence of Hydroxypropyl Methylcellulose Molecular Weight Grade on Water Uptake, Erosion and Drug Release Properties of Diclofenac Sodium Matrix Tablets

Purpose: To comparatively evaluate the effect of two hydroxylpropyl methylcellulose (HPMC) molecular weight grades (K4M and K15M) on drug release from diclofenac sodium matrix tablets.Methods: Tablets containing diclofenac sodium were prepared by direct compression method at various drug/HPMC ratios and evaluated in vitro for their water uptake, erosion and dissolution characteristics over a period of 8 h. Their release data were analyzed according to various release kinetic models.Results: The release rate of diclofenac decreased with increase in polymer content and was dependent on the HPMC type used, with the lower release rate observed in formulations containing the higher molecular weight grade HPMC K15M. Formulations containing the higher molecular weight HPMC (F4, F5 and F6) showed higher water uptake than those containing the lower molecular weight polymer (F1, F2 and F3) (p < 0. 001). The formulations incorporating the lower molecular weight HPMC K4M (F1, F2 and F3) showed higher erosion than those that contained HPMC K15M (F4, F5 and F6) (p < 0.001). Kinetic data based on the release exponent, n, in Peppas model, showed that n values were between 0.14 and 0.55, indicating that drug release from HPMC matrices was predominantly by diffusion.Conclusion: This study demonstrates that the molecular weight (MW) of HPMC does affect the water uptake and erosion as well as the rate of drug release from of HPMC matrices.Keywords: Matrix, Diclofenac sodium, HPMC, Erosion, Water uptake.

Design and evaluation of gastroretentive mucoadhesive cephalexin tablets

The aim of this investigation was to develop gastroretentive mucoadhesive tablets of cephalexin, which will retain in the stomach for 10 h. Cephalexin, a first-generation cephalosporin, becomes ionized in intestinal pH because pKa is 4.5 and thus reducing its bioavailability. The various batches were prepared by wet granulation method using variety of mucoadhesive polymers such as hydroxyl propyl methyl cellulose K4M, hydroxyl propyl cellulose, chitosan, carbopol 934P and sodium carboxymethylcellulose and subjected to various evaluation parameters such as mucoadhesive strength, in vitro drug release profile, swelling characteristics and physical properties. It was evident from the study that the formulation containing HPMC K4M and carbopol 934P in combination exhibited maximum mucoadhesive strength of 144.42 gms, in vitro residence time was 8.73 h and in vitro drug release was found to be 75.03% in 10 h with non-Fickian diffusion mechanism. So, the optimized formulation F2 was further subjected to in vivo retention time in rabbit by X-ray technique, SEM and Accelerated stability studies. Regarding all the properties evaluated, the formulation containing HPMC K4M and carbopol 934P in combination was found to be the best to achieve the aim of this study.

Design and evaluation of gastroretentive mucoadhesive cephalexin tablets

The aim of this investigation was to develop gastroretentive mucoadhesive tablets of cephalexin, which will retain in the stomach for 10 h. Cephalexin, a first-generation cephalosporin, becomes ionized in intestinal pH because pKa is 4.5 and thus reducing its bioavailability. The various batches were prepared by wet granulation method using variety of mucoadhesive polymers such as hydroxyl propyl methyl cellulose K4M, hydroxyl propyl cellulose, chitosan, carbopol 934P and sodium carboxymethylcellulose and subjected to various evaluation parameters such as mucoadhesive strength, in vitro drug release profile, swelling characteristics and physical properties. It was evident from the study that the formulation containing HPMC K4M and carbopol 934P in combination exhibited maximum mucoadhesive strength of 144.42 gms, in vitro residence time was 8.73 h and in vitro drug release was found to be 75.03% in 10 h with non-Fickian diffusion mechanism. So, the optimized formulation F(2) was further subjected to in vivo retention time in rabbit by X-ray technique, SEM and Accelerated stability studies. Regarding all the properties evaluated, the formulation containing HPMC K4M and carbopol 934P in combination was found to be the best to achieve the aim of this study.

Formulation and Evaluation of Bioadhesive Buccal Drug Delivery of Tizanidine Hydrochloride Tablets

The study aim was concerned with formulation and evaluation of bioadhesive buccal drug delivery of tizanidine hydrochloride tablets, which is extensively metabolized by liver. The tablets were prepared by direct compression using bioadhesive polymers such as hydroxylpropyl methylcellulose K4M, sodium carboxymethyl cellulose alone, and a combination of these two polymers. In order to improve the permeation of drug, different permeation enhancers like beta-cyclodextrin (beta-CD), hydroxylpropyl beta-cyclodextrin (HP-beta-CD), and sodium deoxycholate (SDC) were added to the formulations. The beta-CD and HP-beta-CD were taken in 1:1 molar ratio to drug in formulations. Bioadhesion strength, ex vivo residence time, swelling, and in vitro dissolution studies and ex vivo permeation studies were performed. In vitro release of optimized bioadhesive buccal tablet was found to be non-Fickian. SDC was taken in 1%, 2%, and 3% w/w of the total tablet weight. Stability studies in natural saliva indicated that optimized formulation has good stability in human saliva. In vivo mucoadhesive behavior of optimized formulation was performed in five healthy male human volunteers and subjective parameters were evaluated.

Design and Evaluation of Transdermal Drug Delivery System for Curcumin as an Anti-Inflammatory Drug

The purpose of this research was to develop a matrix-type transdermal therapeutic system containing herbal drug, curcumin (CUR), with different ratios of hydrophilic (hydroxyl propyl methyl cellulose K4M [HPMC K4M]) and hydrophobic (ethyl cellulose [EC]) polymeric systems by the solvent evaporation technique. Different concentrations of oleic acid (OA) were used to enhance the transdermal permeation of CUR. The physicochemical compatibility of the drug and the polymers was also studied by differential scanning calorimetry (DSC) and infrared (IR) spectroscopy. The results suggested no physicochemical incompatibility between the drug and the polymers. Formulated transdermal films were physically evaluated with regard to drug content, tensile strength, folding endurance, thickness, and weight variation. All prepared formulations indicated good physical stability. In vitro permeation studies of formulations were performed by using Franz diffusion cells. The results followed Higuchi kinetics, and the mechanism of release was diffusion-mediated. Formulation prepared with hydrophilic polymer containing permeation enhancer showed best in vitro skin permeation through rat skin as compared with all other formulations. This formulation demonstrated good anti-inflammatory activity against carrageenan-induced oedema in Wistar albino rats similar to standard formulation.

Evaluation of effervescent floating matrix tablet formulations of salbutamol sulfate using full factorial design

The purpose of this research was to formulate and optimize an effervescent floating tablet formulation of salbutamol sulfate using full factorial design. Salbutamol sulfate has an absorption window in the stomach and in the upper part of the small intestine. A 32 full factorial design (eight runs) was utilized to optimize the formulation wherein the content of hydroxylpropyl methyl cellulose (HPMC) (X1) and sodium bicarbonate (X2) were taken as independent variables and % drug release after 6 h (Y1), t50% (Y2), and buoyancy lag time (BLT) (Y3) were taken as the dependent variables. Salbutamol sufate, HPMC K4M and HPMC K100M CR, stearic acid, talc, dicalcium phosphate, polyvinyl pyrrolidone, and magnesium stearate were used for the current research work. Two viscosity grades of HPMC as matrix materials were used for formulating the tablets, which were prepared by wet granulation. The release data were evaluated by the model-dependent (curve fitting) method using the PCP Disso v2.08 software. Optimization studies were carried out using the Design Expert Software (Version 7.0.3). The in vitro drug release mechanism showed anomalous transport. An increase in the concentration and viscosity grade of the polymer resulted in a decrease in the release rate, but it was found that at a higher concentration of HPMC, the viscosity grade did not significantly affect the drug release. Concentration of both HPMC and sodium bicarbonate had a significant effect on the BLT. Optimized effervescent floating tablets of salbutamol sulfate were successfully prepared and a good correlation was observed between predicted and actual values of the dependent variables chosen for the study. Viscosity grade of HPMC did not significantly impact the floatability of the dosage form. Thus, we can conclude that a combination of HPMC, stearic acid, and sodium bicarbonate can be used to increase the gastric residence time of the dosage form up to 12 h.

Preparation and evaluation of a novel buccal adhesive system

The aim of the present study was to prepare and evaluate a novel buccal adhesive system (NBAS) containing propranolol hydrochloride (PH). A special punch was fabricated and used while preparing an NBAS. Solubility of PH in phosphate buffer solution (pH 6.6), partition coefficient between phosphate buffer (pH 6.6) and 1-octanol, and permeability coefficient through the porcine buccal mucosa were performed and found to be 74.66 mg/mL, 5.17, and 5.6, respectively. Stability of NBAS was determined in natural human saliva, and it was found that both PH and device are stable in human saliva. NBAS was evaluated by weight uniformity, thickness, hardness, friability, swelling, mucoadhesive strength, in vitro drug release, and in vivo human acceptability studies. Swelling index was higher (4.4) for formulations containing hydroxyl propyl methyl cellulose (HPMC) K4M alone, and it decreases with its decreasing concentration in the NBAS. Mucoadhesive strength (MS) was measured by using a modified apparatus. All NBASs showed higher MS with porcine buccal mucosa when compared with that of rabbit buccal mucosa. NBASs containing carbopol (CP) 934P and HPMC K4M at the ratio of 1:1 showed higher MS (44.76 g) with porcine buccal mucosa when compared with 1:2 (39.76 g), 0:1 (23.29 g), and 1:0 (22.22 g) ratios, respectively. The mechanism of PH release was found to be by non-Fickian diffusion (value of "n" between 0.5 and 1.0) and followed first order kinetics. In vivo human acceptability study showed that the newly prepared NBAS was comfortable in the human buccal cavity. It can be concluded that NBAS is a superior, novel system that overcomes the drawback associated with the conventional buccal adhesive tablet.

Sulphamethizole-Cyclodextrin-Hydroxy Propylmethyl Cellulose Multicomponent Complexes

The effect of cyclodextrin complexation of sulphamethizole (SM) was studied. Two systems were prepared with two cyclodextrin derivatives, β-cyclodextrin (BCD) and hydroxypropyl-β-cyclodextrin (HPBCD): binary complexes and multicomponent systems (cyclodextrins and a hydroxylpropylmethyl cellulose K4M). Inclusion complexes were prepared by freeze-drying and characterized by thermal analysis (DSC) and X-ray diffractometry. The presence of the polymer in the solution increases the effect of cyclodextrins – specially BCD – on the solubility of SM. In solid state, binary inclusion complexes enhance the dissolution behaviour of SM but, from the multi-component complexes, the polymer controls the release of the drug.