Mucoadhesive Drug Delivery System

A primary object of using mucoadhesive formulations orally would
achieve a substantial increase in the length of stay of the drug in GI
tract  stability  problem  in  the  intestinal  fluid  can  be  improved.
Mucoadhesive  microsphere  carrier  systems  were  made  from  the
biodegradable polymers in sustained drug delivery. The objective of
the  present  study  is  related  to  the  preparation  and  evaluation  of
mucoadhesive  microspheres  of  simvastatin  by  using  different
polymers like Sodium alginate, HPMC K100M, Sodium CMC, Ethyl
cellulose, Methyl cellulose, Guar gum, Xanthan gum and Carbopol
940 in different ratios by the Ionic deletion method. The prepared
batches of mucoadhesive microspheres of simvastatin were evaluated
for  the  flow  properties;  drug  content,  entrapment  efficiency,  and
Percent mucoadhesive property, in vitro dissolution studies of all 12
formulations were performed. From the all batches F10 (Drug: Sod.
Alginate: Methyl cellulose 1:2:1) batch is considered to be the most
promising formulation batch because among all the batches it shows
better  extent  of  drug  release  97.11%  (8hrs),  good  entrapment
efficiency  (78%),  and  in  vitro  wash-off  test  shows  the  good
mucoadhesive property. Simvastatin release from alginate – Methyl
cellulose (F10)  was  slow and extended over a period of 8 hrs and
these microspheres were found suitable for the oral controlled release
formulation.

Buccal delivery involves the administration of the desired drug through the buccal mucosal membrane lining of the oral cavity. The objective of this article is to review buccal drug delivery by discussing the structure and environment of the oral mucosa and highlighting the mechanisms of drug permeation and methodology in evaluating buccal formulations. This review also highlights a brief description of advantages, limitations of buccal drug delivery and theories involved in mucoadhesion along with method of preparation mucoadhesive system, mucoadhesive polymer, and classification of buccal system.

Mucoadhesion was employed for improving performance and bioavailability of many drugs. Different dosage forms were developed based on this principle. This study aims to prepare bucco-adhesive tablets of anti-migraine drug zolmitriptan as a suitable candidate for improving its oral bioavailability and therapeutic efficacy and to evaluate them for many pre/post-formulation parameters in-vitro/exvivo. The bucco-adhesive tablets containing 2.5 mg zolmitriptan were prepared using carbopol 934LR as a primary polymer alone or in combination with chitosan or xanthan gum as secondary polymers by direct compression. Drug-excipients compatibility and micromeritics study were carried out. Tablets were evaluated for physico-chemical parameters, surface pH, ex-vivo residence time, in-vitro swelling study, ex-vivo mucoadhesive strength, in-vitro drug release study, ex-vivo permeation study and physical stability in human saliva. No interactions were found between drug and excipients. Tablets had good physico-chemical characters. Formulation containing carbopol 934LR and chitosan in a ratio of 1: 3 approximately was the optimum one. It swelled by only 37.67±0.65% after 5 h and showed a nearly neutral surface pH. Ex-vivo residence time was long enough for delivery of the drug for more than 8 h. Ex-vivo mucoadhesive strength was 32.7±2.1 g. Drug release was 86.93±3.73 % after 7 h following zero order kinetics and permeation flux was 0.045 mg/cm 2 h. Tablets were physically stable W WO OR RL LD D J JO OU UR RN NA AL L O OF F P PH HA AR RM MA AC CY Y A AN ND D P PH HA AR RM MA AC CE EU UT TI IC CA AL L S SC CI IE EN NC CE ES S V Vo ol lu um me e 2 2, , I Is ss su ue e 6 6, , 4 42 22 25 5--4 42 24 48 8. . R Re es se ea ar rc ch h A Ar rt ti ic cl le e I

The main objective of this study was to assess awareness of danger
signs of pregnancy and its associated factors in Mekelle public
hospitals, 2014.
Institutional based cross sectional study was conducted among 422
pregnant mothers. Data was collected using interviewer administered
questionnaire; it was entered and analyzed using SPSS version 16.
The data were presented using texts, graphs and tables.
Out of the total participants of this study 79.6% mothers had
information about danger signs of pregnancy from which 61.9%
mothers had information about vaginal bleeding followed by sudden
gush of fluid before labor which was mentioned by 41.9% of
respondents. Severe unusual abdominal pain was the least known
danger signs as mentioned by 19 % of mothers. The main source of
information for the danger signs was health personnel and
Negligence was the main reason for not having good awareness about
danger signs of pregnancy.
Therefore, health extension workers should strengthen their
awareness creation activities; community mobilization and health
education should be considered with policy makers and other
interested organizations.

oligonucleotides have predominant role in its delivery for various
diseases. Objective: Antisense compounds are biological
molecules consisting of small ribonucleic acid (RNA) or
deoxyribonucleic acid (DNA) segments (Oligonucleotide) which
have enormous potential for the treatment of number of diseases.
Methods: All the methods analyzed were obtained through high
impact articles. Results: Several impediments were made to
Oligonucleotide for its widespread usage as them as drugs to
overcome their lack of stability in physiological fluids and their
poor penetration into cells. Experiments like, association with or
encapsulation within nano-and micro sized drug delivery systems,
lipids and polymers could help to increase the efficiency of
oligonucleotide delivery. This review discusses the use of cationic
lipids, Cell penetrating peptides, nanoparticles, microparticles and
several novel methods that have recently been explored as delivery
vehicles. Conclusion: The use of naked Oligonucleotide given a
clear cut way to new targets for potential therapeutic compounds.
Apart this, antisense therapy represents a promising and evolving
approach to the management of numerous diseases in which a
specific abnormality has been identified as a primary or major
contributing etiologic factor. In near future, authors strongly
believe that antisense therapy will give a positive way for number
of In vitro experiments and break through for many life
threatening diseases.

The present work was aimed to design & characterize an oral dosage form to release Terbutaline sulphate following a programmed time period (pulsed release system). Pulsatile release tablet comprises a drug containing core and pH sensitive polymeric coating capable of delaying drug release and providing gastric resistance .The core tablets of terbutaline sulphate were prepared for the treatment of nocturnal asthma .The core tablets were prepared by direct compression method using different disintegrating agents. The cores were coated with pH sensitive polymers (Eudragit S-100, Eudragit L-100) at different coating levels to develop a suitable dosage form which should show minimum drug release in upper regions of gastrointestinal tract (GIT). Prepared tablets were characterized for various physical parameters such as hardness, thickness, weight variation disintegration test drug content and in-vitro drug release characteristics. All the parameters were found to be in the standard range. The dissolution of best formulation F 4 S 3 , F 7 S 3 and F 11 S 3 have shown the lag phase of 5 hrs at 10% coating level and almost complete drug release was achieved after 11 hrs . The kinetic study data for best formulation followed zero order kinetics. Stability study of the best formulation indicates no significant difference in release profile after a period of 3 months.

The objective of the research was firstly to investigate the behavior of Surelease (release retardant binder) alone and in combination with other hydrophilic polymers on the release of zidovudine from sustained release matrix tablet. Secondly, to compare between the release pattern of polyethylene oxide and Methocel K100M alone and in combination. A randomized surface methodology (RSM) was applied to study the effect of polymers on drug release. The independent variables of the formulation were: the type of polymers (X1), concentration of polymers (X2) in the tablet and dependent variables are the percentage drug release at 2 hours (Y1) and the percentage drug release at 12 hours (Y 2 ). Release kinetics were analyzed using zero-order, first order, higuchi's square root and korsmeyer-peppas empirical equations in terms of r 2 . Results of invitro drug release kinetics study suggests that, all formulations follows zero order kinetics with r 2 value in range of 0.99 and fitting the release data to korsmeyers equation release exponent n ranged from 0.83 to 1.22 and followed non-Fickian diffusion mechanism (anomalous transport) and super case II transport for Surelease formulations. Among all the formulations, F14 matrix tablet containing combination of Surelease and polyoxWSR301 shows 102.37% of drug release at the end of 12 hours.

The goal of any drug delivery system is to provide a therapeutic amount of drug to the proper site in the body to achieve promptly & then maintain the desired drug concentration. That is why the drug delivery system should deliver dr ug at a state dictated by the needs of the body over a specified period of treatment. This idealized objective points to the two aspects most important to drug delivery, namely, spatial placement relates to targeting a drug to a specific organ or tissue while temporal delivery refers to the control of rate of drug delivery to the target tissue. Bioadhesion can be defined as the process by which a natural or a synthetic polymer can adhere to a biological substrate. When the biological substrate is a mucosal layer then the phenomena is known as mucoadhesion. The substrate possessing bioadhesive property can help in devising a delivery system capable of delivering a bioactive agent for a prolonged period of time at a specific delivery site. The current rev...

Febuxostat is a urate lowering drug, an inhibitor of xanthine
oxidase used in the treatment of hyperuricemia and chronic gout. The
drug shows dissolution-rate limited absorption, there by poor and
variable bioavailability. It needs enhancement in bioavailability to
derive maximum therapeutic efficacy. The main objective of the
present research work is to enhance the solubility and dissolution rate
of Febuxostat by preparing the Spherical agglomerates. Spherical
agglomerates were prepared by the quasi emulsion solvent diffusion
method. N, N-dimethyl form amide, chloroform and water were
selected as good solvent, bridging liquid and poor solvents
respectively. Polyethylene glycol, Poloxomer- F68 and Polyvinyl
alcohol were used as a carrier. Among all the formulations prepared,
spherical agglomerates prepared with Febuxostat and Poloxomer-
F68 in 1:1 ratio showed highest drug release in 60 minutes. Spherical
agglomerates prepared with Febuxostat and Poloxomer- F68 in 1:1
ratio was used in the preparation of orodispersible tablets. To study
the influence of superdisintegrants on performance of Febuxostat
Orodispersible Tablets, a set of three formulations (K1, K2, K3) were
prepared using three superdisintegrants sodium starch glycolate,
Croscarmalose sodium and Crospovidone . The orodispersible tablets
of Febuxostat prepared with Crospovidone showed rapid drug release
when compared to pure drug and other tablet formulations.

The present study was aimed to formulate and evaluate fast
dissolving oral films of Zolmitriptan using sodium alginate, xanthan
gum and sodium starch glycolate, guar gum. The suitable plasticizer
and its concentration were selected on the basis of flexibility, tensile
strength and stickiness of the film. The films are prepared by solvent
casting method and characterized by UV, FTIR studies. The films
were evaluated for disintegration time, Folding endurance, Tensile
Strength, Mouth dissolving time, Thickness, content uniformity and
In-vitro dissolution studies. The F5 formulation has given 98.5% drug
release within 6 minutes and has a tensile strength of 1.80 MPa.

The current study was aimed to develop the meclizine hydrochloride
sublimated fast dissolving tablets using different sublimated agents to
enhance the dissolution rate. The prepared fast dissolving tablets
were subjected to pre-compression properties and characterized for
hardness, weight variation, friability, wetting time, water absorption
ratio, and disintegration time. From In vitro dissolution studies, the
formulation F3 containing camphor (10%w/w) as the sublimating
agent showed rapid dissolution of about 98.61% in 30 min, and
disintegration time 43 sec when compared with other sublimating
agents. The percent drug release in 30 min (Q30) and initial
dissolution rate for formulation F3 was 98.61±0.25%, 3.29%/min.
These were very much higher compared to marketed tablets
(65.43±0.57%, 2.18%/min). The dissolution efficiency was found to
be 63.37 and it is increased by 1.4 fold with F3 FDT tablets
compared to marketed tablets. Differential scanning calorimetry and
Fourier transform infrared spectroscopy studies revealed that there
was no possibility of interactions. In conclusion, development of
meclizine hydrochloride fast dissolving tablets by sublimation
method is an appropriate method to enhance the dissolution rate.

The goal of any drug delivery system is to provide a therapeutic amount of drug to the proper site in the body to achieve promptly {\&} then maintain the desired drug concentration. That is why the drug delivery system should deliver dr ug at a state dictated by the needs of the body over a specified period of treatment. This idealized objective points to the two aspects most important to drug delivery, namely, spatial placement relates to targeting a drug to a specific organ or tissue while temporal delivery refers to the control of rate of drug delivery to the target tissue. Bioadhesion can be defined as the process by which a natural or a synthetic polymer can adhere to a biological substrate. When the biological substrate is a mucosal layer then the phenomena is known as mucoadhesion. The substrate possessing bioadhesive property can help in devising a delivery system capable of delivering a bioactive agent for a prolonged period of time at a specific delivery site. The current review provides a good insight on mucoadhesive polymers, the phenomenon of mucoadhesion and the factors which have the ability to affect the mucoadhesive properties of a polymer. CONCLUSION Of late, scientists are trying to improve the bioavailability of active agents by tailoring the properties of the delivery systems instead of designing new active agents. Mucoadhesive polymers may provide an important tool to improve the bioavailability of the active agent by improving the residence time at the delivery site. The various sites where mucoadhesive polymers have played an important role include buccal cavity, nasal cavity, rectal lumen, vaginal lumen and gastrointestinal tract. Development of novel mucoadhesive delivery systems are being undertaken so as to understand the various mechanism of mucoadhesion and improved permeation of active agents. Mucoadhesive dosage forms have a high potential of being useful means of delivering drugs to the body, perhaps particularly for topical or local administration where the mechanical trauma experienced by the dosage form may be minimized. Current use of mucoadhesive polymers to increase contact time for a wide variety of drugs and routes of administration has shown dramatic improvement in both specific therapies and more general patient compliance. The general properties of these polymers for purpose of sustained release of chemicals are marginal in being able to accommodate a wide range of physicochemical drug properties. Hence mucoadhesive polymers can be used as means of improving drug delivery through different routes like gastrointestinal, nasal, ocular, buccal, vaginal and rectal. Many potential mucoadhesive systems are being investigated which may find their way into the market in near future.

Polycaprolactone (PCL) nanoparticles decorated with a mucoadhesive polysaccharide chitosan (CS) containing curcumin were developed aiming the buccal delivery of this drug. These nanoparticles were prepared by the nanoprecipitation method using different molar masses and concentrations of chitosan and concentrations of triblock surfactant poloxamer (PEO–PPO–PEO), in order to optimize the preparation conditions. Chitosan-coated nanoparticles showed positive surface charge and a mean particle radius ranging between 114 and 125 nm, confirming the decoration of the nanoparticles with the mucoadhesive polymer, through hydrogen bonds between ether and amino groups from PEO and CS, respectively. Dynamic Light Scattering (DLS) studies at different scattering angles and concentrations have shown that the nanoparticles are monodisperse (polydispersity indices were lower than 0.3). The nanoparticle systems were also examined with Nanoparticle Tracking Analysis (NTA), and the results were in good agreement with those obtained by DLS. Colloidal systems showed mean drug content about 460 μg/mL and encapsulation efficiency higher than 99%. Finally, when coated with chitosan, these nanoparticles show a great ability to interact with mucin indicating also their suitability for mucoadhesive applications.

Mucoadhesive patches containing 10 mg miconazole nitrate were evaluated. The patches were prepared with ionic polymers, sodium carboxymethyl cellulose (SCMC) and chitosan, or non-ionic polymers, polyvinyl alcohol (PVA), hydroxyethyl cellulose (HEC) and hydroxypropylmethyl cellulose (HPMC). Convenient bioadhesion, acceptable elasticity, swelling and surface pH were obtained. Patches exhibited sustained release over more than 5 h and the addition of polyvinyl pyrrolidone (PVP) generally enhanced the release rate. Optimum release behaviour was shown with patches containing 10% w/v PVA and 5% w/v PVP. Study of the in vivo release from this formulation revealed uniform and effective salivary levels with adequate comfort and compliance during at least 6 h. On the contrary, in vivo release of the commercial oral gel product resulted in a burst and transient release of miconazole, which diminished sharply after the first hour of application. Storage of these patches for 6 months did not affect the elastic properties, however, enhanced release rates were observed due to marked changes in the crystal habit of the drug.

The current study aimed at development and validation of a simple, accurate, precise, sensitive, robust and specific high performance liquid chromatography (HPLC) method for simultaneous estimation of benzocaine (BZN) with tibezonium iodide (TIB) from combined dosage form as well as from human saliva. Instrumental conditions were developed on an auto-sampler Agilent® 1260 Infinity series RP-HPLC machine. The method was validated in accordance with ICH harmonized guidelines Q2 (R1) by using acetonitrile and phosphate buffer as mobile phase in a volumetric proportion of 70:30 which was flowing through C 18 Agilent® column. Flow of mobile phase was maintained at 1 mL/min at 35 °C and elute was detected 318 nm. The peaks for BZN and TIB were separated at 2.29 and 4.15 min, respectively. Linearity range for such were 0.24-20.16 and 0.14-10.08 μg/mL, respectively. Linear coefficient of regression (R2) for BZN and TIB were 0.9987 and 0.9993, respectively. The relative standard deviation (RSD) values for both drugs were less than 2.0% indicating the accuracy and precision. The limit of detection (LOD) and limit of quantification (LOQ) outcomes for BZN were 56 and 187 ng/mL, respectively. For TIB, it were 38 and 127 ng/mL, respectively. The drugs separation against placebo justified the specificity of the method. It was concluded that the developed and validated method could be potentially for in vitro as well as in human salivary extracts of formulated dosage forms.

Polycaprolactone (PCL) nanoparticles decorated with a mucoadhesive polysaccharide chitosan (CS) containing curcumin were developed aiming the buccal delivery of this drug. These nanoparticles were prepared by the nanoprecipitation method using different molar masses and concentrations of chitosan and concentrations of triblock surfactant poloxamer (PEO-PPO-PEO), in order to optimize the preparation conditions. Chitosan-coated nanoparticles showed positive surface charge and a mean particle radius ranging between 114 and 125 nm, confirming the decoration of the nanoparticles with the mucoadhesive polymer, through hydrogen bonds between ether and amino groups from PEO and CS, respectively. Dynamic Light Scattering (DLS) studies at different scattering angles and concentrations have shown that the nanoparticles are monodisperse (polydispersity indices were lower than 0.3). The nanoparticle systems were also examined with Nanoparticle Tracking Analysis (NTA), and the results were in good agreement with those obtained by DLS. Colloidal systems showed mean drug content about 460 lg/mL and encapsulation efficiency higher than 99%. Finally, when coated with chitosan, these nanoparticles show a great ability to interact with mucin indicating also their suitability for mucoadhesive applications.

This work evaluated under accelerated conditions the stability of the
biodegradable gentamicin-glyceryl monooleate water based-gel used
in the treatment of chronic osteomyelitis. Three batches of 600.0 g of
gentamicin -glyceryl monooleate -water based-gel (5/80/15% w/w)
were manufactured. The samples were stored in a climatic test
chamber for stability evaluation according to the standards published
by the International Conference on Harmonisation and the World
Health Oganization (25 ± 2°C / 60 ± 5%RH) for 6 months. Samples
were evaluated at pre-determinate times 0, 3 and 6 months with
regard to their physicochemical properties and In Vitro drug release
characteristics. Gentamicin sulfate present in the freshly prepared
gels was the same after three and six months of storage at 25°C / 60%
RH. However the relative amount of gentamicin sulfate in the freshly
prepared gel that was about 110% decreased by about 11% after six
months of storage. The release profiles of the gels remained similar
despite a partial hydrolysis of glyceryl monooleate and an increase in
the residual amount of water and in the viscosity.

Pain treatment by means of a local anesthetic and at the same time, controlling the microbial flora with an antiseptic agent can be considered as an option for delivering through mucoadhesive buccal dosage form. The objective of the current study was to develop a chitosan (CHI) based targeted polymeric buccal mucoadhesive fabrication for simultaneous release of lignocaine hydrochloride (LGN) and tibezonium iodide (TBN). Mixed ingredients were compacted via direction compression using chitosan (CHI) with sodium alginate (SA) and hypromellose (HPMC). Outcomes shown that the weight variation and friability were according to the USP specifications and were unaffected by changing amounts of the polymers in the formulations. Maximum swellability was observed in PT8, containing 7.5% of SA and CHI. Surface pH was also in accordance to the normal physiological pH range. Maximum mucoadhesive strength and time values were observed in the formulation PT4 containing 7.5% concentration of CHI and HPMC each, which were 5.76 h and 9.37 g, respectively. Same was the case for PT4 in terms of maximum simultaneous in vitro release for both drugs. The release of TBN and LGN was best fitted to Hixon Crowell release model. Formulation PT4 promised optimum results in terms of maximum release with optimum mucoadhesive values till to 4 h. RESUMEN. El tratamiento del dolor por medio de un anestésico local y al mismo tiempo, el control de la flora microbiana con un agente antiséptico puede considerarse como una opción para su administración a través de una forma de dosificación bucal mucoadhesiva. El objetivo del presente estudio fue desarrollar una fabricación mucoadhesiva bucal polimérica dirigida basada en quitosano (CHI) para la liberación simultánea de clorhidrato de lignocaína (LGN) y yoduro de tibezonio (TBN). Los ingredientes mezclados se compactaron mediante compresión direccional usando quitosano (CHI) con alginato de sodio (SA) e hipromelosa (HPMC). Los resultados mostraron que la variación de peso y la friabilidad estaban de acuerdo con las especificaciones de la USP y no se vieron afectadas por las cantidades cambiantes de los polímeros en las formulaciones. Se observó una máxima hinchabilidad en PT8, que contenía un 7,5% de SA y CHI. El pH de la superficie también estuvo de acuerdo con el rango de pH fisiológico normal. Se observaron valores máximos de fuerza mucoadhesiva y tiempo en la formulación PT4 que contenía una concentración del 7,5% de CHI y HPMC cada una, que fueron 5,76 hy 9,37 g, respectivamente. Lo mismo sucedió con PT4 en términos de liberación in vitro simultánea máxima de ambos fármacos. El lanzamiento de TBN y LGN se ajustó mejor al modelo de lanzamiento de Hixon Crowell. La formulación PT4 prometía resultados óptimos en términos de liberación máxima con valores mucoadhesivos óptimos hasta las 4 h.

Cetylpyridinium chloride (CPC), a quaternary antiseptic, has been found effective in controlling the accumulation of bacterial plaque and the consequent gingivitis (1). The drug has bactericidal activity against Gram-positive and, at higher concentrations, against Gram-negative organisms. It has a good activity against Candida albicans (2). Lozenges and mouthwashes are available but none of these dosage forms can release the antiseptic drug into the oral cavity for a prolonged period because of their short residence time (3). Multilayered bioadhesive lozenges containing CPC were evaluated (4); they were not erodible and required removal after 3 h. A buccoadhesive erodible disk was designed (1), which showed a controlled and delayed release pattern at the targeted Mucoadhesive patches for delivery of cetylpyridinium chloride (CPC) were prepared using polyvinyl alcohol (PVA), hydroxyethyl cellulose (HEC) and chitosan. Swelling and bioadhesive characteristics were determined for both plain and medicated patches. The results showed a remarkable increase in radial swelling (S D ) after addition of the water-soluble drug (CPC) to the plain formulae. A decrease in the residence time was observed for PVA and chitosan-containing formulae. Higher drug release was obtained from PVA patches compared to HEC ones, while both are non-ionic polymers. A considerable drop in release was observed for chitosan formulae after the addition of water-soluble additives, polyvinyl pyrrolidone (PVP) and gelatin. Ageing was done on PVA formulae; the results showed there was no influence on the chemical stability of CPC, as reflected from the drug content data. Physical characteristics of the studied patches showed an increase in the residence time with storage accompanied with a decrease in drug release. This may be due to changes in the crystal habit of the drug as well as to slight agglomeration of the polymer particles.

The objective of present study was to modify the surface of
Poly(D,L-lactide-co-glycolide acid) (PLGA) nanoparticles (NPs)
with chitosan to enhance the mucoadhesive potential of carrier
system. Grafting of chitosan on PLGA surface was carried out
via amide bond formation mediated by carbodiimide and confirmed by FTIR spectroscopy. Self-assembled PLGA NPs containing chlorpromazine hydrochloride were fabricated by 23 factorial
design. The improved mucoadhesive potential was confirmed by
several tests including in vitro mucoadhesion study. Ex vivo permeation was satisfactory. Histopathological study on sheep nasal mucosa revealed safe mucoadhesion. They were also found to be robust on accelerated stability study.

The goal of any drug delivery system is to provide a therapeutic amount of drug to the proper site in the body to achieve promptly & then maintain the desired drug concentration. That is why the drug delivery system should deliver dr ug at a state dictated by the needs of the body over a specified period of treatment. This idealized objective points to the two aspects most important to drug delivery, namely, spatial placement relates to targeting a drug to a specific organ or tissue while temporal delivery refers to the control of rate of drug delivery to the target tissue. Bioadhesion can be defined as the process by which a natural or a synthetic polymer can adhere to a biological substrate. When the biological substrate is a mucosal layer then the phenomena is known as mucoadhesion. The substrate possessing bioadhesive property can help in devising a delivery system capable of delivering a bioactive agent for a prolonged period of time at a specific delivery site. The current review provides a good insight on mucoadhesive polymers, the phenomenon of mucoadhesion and the factors which have the ability to affect the mucoadhesive properties of a polymer.

Mucoadhesion was employed for improving performance and bioavailability of many drugs. Different dosage forms were developed based on this principle. This study aims to prepare bucco-adhesive tablets of anti-migraine drug zolmitriptan as a suitable candidate for improving its oral bioavailability and therapeutic efficacy and to evaluate them for many pre/post-formulation parameters in-vitro/ex-vivo. The bucco-adhesive tablets containing 2.5 mg zolmitriptan were prepared using carbopol 934LR as a primary polymer alone or in combination with chitosan or xanthan gum as secondary polymers by direct compression. Drug-excipients compatibility and micromeritics study were carried out. Tablets were evaluated for physico-chemical parameters, surface pH, ex-vivo residence time, in-vitro swelling study, ex-vivo mucoadhesive strength, in-vitro drug release study, ex-vivo permeation study and physical stability in human saliva. No interactions were found between drug and excipients. Tablets had ...

From the previous work (Part I), mucoadhesive formulae containing 5% CP/65% HPMC/30% lactose and 2% PC/68% HPMC/30% mannitol as well as formulae based on sodium carboxymethyl cellulose (SCMC) were selected. Medicated tablets were prepared using diltiazem hydrochloride (DZ) and metclopramide hydrochloride (MP) in two different doses (30 and 60 mg). The effect of drug and dose on the mucoadhesive properties and in-vitro drug release was evaluated. All formulae produced extended drug release (over 8 to 12 h). Polyacrylic acid based matrices (PAA) showed Fickian's diffusion release pattern for both drugs. SCMC ensured zero-order release for DZ, which deviated to anomalous behavior in case of MP. Doubling the dose significantly reduced the bioadhesion strength (p<0.05) with a slight improvement in drug release rate. The formulation of bilayer tablets containing drug-free layer and medicated layer enhanced the drug release without affecting the bioadhesive performance. The bilayer tablet formulated with 2% PC/68% HPMC/30% mannitol (PC2) was selected for studying the in-vivo metoclopramide release in four healthy volunteers. The tablet ensured controlled drug release for 12 h, in addition, good correlation (r=0.9398) was observed between in-vitro and in-vivo data. The effect of ageing on selected formulae containing DZ and MP, respectively, was studied. Storage at 40 degrees C and 75% relative humidity for 6 months didn't influence the mucoadhesive performance, however, an enhanced released rate was observed.

The objective of this study is to evaluate the effect of formulation variables on different evaluation properties such as cumulative percentage release and swelling index in development of two layered buccal mucoadhesive system consisting of a highly water soluble drug risedronate sodium. The mucoadhesive systems were developed with varied concentrations of the polymers (1-2%) using plasticizer/permeation enhancer (25-50% w/w of polymer). Two layered films comprised of risedronate sodium with chitosan (85% deacetylated) and hydroxypropylmethyl cellulose (HPMC 4KM) interpolymer complex of different ratios were prepared by solvent casting method. An impermeable backing membrane of ethyl cellulose was incorporated into the films. The study shows the effect of multipolymeric films on the release of a bisphosphonates derivative. The optimized formulations showed films with uniform drug content (90.91 ± 0.17-105.53% ± 2.15), thickness (0.22 ± 0.01 mm to 0.31 ± 0.06 mm), mucoadhesivity (26 ± 3.61-42.33 ± 2.82 g), and controlled drug release profile up to a period of 10 hours. The films were also studied for swelling index, moisture uptake, viscosity, folding endurance, water vapor transmission rate, and mucoadhesive time.

Mucoadhesion was employed for improving performance and bioavailability of many drugs. Different dosage forms were developed based on this principle. This study aims to prepare bucco-adhesive tablets of anti-migraine drug zolmitriptan as a suitable candidate for improving its oral bioavailability and therapeutic efficacy and to evaluate them for many pre/post-formulation parameters in-vitro/exvivo. The bucco-adhesive tablets containing 2.5 mg zolmitriptan were prepared using carbopol 934LR as a primary polymer alone or in combination with chitosan or xanthan gum as secondary polymers by direct compression. Drug-excipients compatibility and micromeritics study were carried out. Tablets were evaluated for physico-chemical parameters, surface pH, ex-vivo residence time, in-vitro swelling study, ex-vivo mucoadhesive strength, in-vitro drug release study, ex-vivo permeation study and physical stability in human saliva. No interactions were found between drug and excipients. Tablets had g...

Plants gums are complex mixtures of different polysaccharides with a variety of biological activities and pharmaceutical applications. Few studies have focused on physicochemical and biological properties of gums obtained from different plants. This study was designed to determine potential pharmaceutical and pharmacological values of the gum exudates and its isolated biopolymers obtained from Astragalus myriacanthus Boiss [syn. Astracantha myriacantha (Boiss.) Podlech] (Fabaceae). The physicochemical, rheological, and mucoadhesion properties of the gum and its fractions was measured at 7, 27, and 37 °C with and without the presence of NaCl (1%). Also, the structural and immunomodulatory properties of several water soluble biopolymers isolated using ion exchange and size exclusion chromatographic methods were investigated on Jurkat cells at concentrations of 31.25, 62.5, 125, 250, 500 and 1000 μg/mL. The consistency and shear-thinning property of the gum and its fractions decreased as temperature increased. In the presence of NaCl, the consistency increased but no regular pattern was observed regarding to shear-thinning behavior. The mucoadhesion strength was 40.66 ± 2.08 g/cm 2 which is suitable for use as a formulary mucoadhesive polymer. The isolated biopolymers had proteo-arabinoglycan structure. Their molecular weight was calculated to be 1.67-667 kDa. One biopolymer had a proliferative effect and others had dose dependent cytotoxic/proliferative properties. The crude gum and its insoluble fraction showed suitable mucoadhesion, swellability and rheological properties which makes them suitable for designing drug delivery systems. The gum proteo-arabinoglycans with different molecular weight and structures had different immunomodulatory properties.

Stimuli-responsive bacterial cellulose-g-poly-(acrylic acid) hydrogels were investigated for their potential use as an oral delivery system for proteins. These hydrogels were synthesized using electron beam irradiation without any cross-linking agents, thereby eliminating any potential toxic effects associated with cross-linkers. Bovine serum albumin (BSA), a model protein drug, was loaded into the hydrogels, and the release profile in simulated gastrointestinal fluids was investigated. Cumulative release of less than 10% in simulated gastric fluid (SGF) demonstrated the potential of these hydrogels to protect BSA from the acidic environment of the stomach. Subsequent conformational stability analyses of released BSA by SDS-PAGE, circular dichroism, and an esterase activity assay indicated that the structural integrity and bioactivity of BSA was maintained and preserved by the hydrogels. Furthermore, an increase in BSA penetration across intestinal mucosa tissue was observed in an ex vivo penetration experiment. Our fabricated hydrogels exhibited excellent cytocompatibility and showed no sign of toxicity, indicating the safety of these hydrogels for in vivo applications.