Lack of mucoadhesive properties is the major drawback to poloxamer 407(F127)-based in situ hydrogels for mucosal administration. The objective of the present study was to construct a novel mucoadhesive and thermosensi...Lack of mucoadhesive properties is the major drawback to poloxamer 407(F127)-based in situ hydrogels for mucosal administration. The objective of the present study was to construct a novel mucoadhesive and thermosensitive in situ hydrogel drug delivery system based on an aminofunctionalized poloxamer for vaginal administration. First, amino-functionalized poloxamer 407(F127-NH2) was synthesized and characterized with respect to its micellization behavior and interaction with mucin. Then using acetate gossypol(AG) as model drug, AG-loaded F127-NH2-based in situ hydrogels(NFGs) were evaluated with respect to rheology, drug release, ex vivo vaginal mucosal adhesion, in vivo intravaginal retention and local irritation after vaginal administration to healthy female mice. The results show that F127-NH2 is capable of forming a thermosensitive in situ hydrogel with sustained drug release properties. An interaction between positively charged F127-NH2 and negatively charged mucin wasrevealed by changes in the particle size and zeta potential of mucin particles as well as an increase in the complex modulus of NFG caused by mucin. Ex vivo and in vivo fluorescence imaging and quantitative analysis of the amount of AG remaining in mouse vaginal lavage all demonstrated greater intravaginal retention of NFG than that of an unmodified F127-based in situ hydrogel. In conclusion, amino group functionalization confers valuable mucoadhesive properties on poloxamer 407.展开更多
The objective of the study was to investigate the potential of montmorillonite as a sustained carrier in the preparation of drug-loaded nanoparticles for prolonged ocular application. Nanoparticles were prepared by io...The objective of the study was to investigate the potential of montmorillonite as a sustained carrier in the preparation of drug-loaded nanoparticles for prolonged ocular application. Nanoparticles were prepared by ionic gelation of chitosan with sodium tripolyphosphate (TPP). Betaxolol hydrochloride (BH) was applied as a model drug. TG, FT-IR, TEM, DLS and XRD have been employed in the characterization of drug-encapsulated chitosan-montmorillonite/TPP nanoparticles (CS-MMT/TPP NPs). TEM images showed that the particles were spherical in shape and had a rough surface. The size range of the nanoparticles was between 338 and 585 nm with positive zeta potential values from 24 mV to 36 mV and encapsulation efficiency values ranging from 12.27% to 50.92%. In vitro sustained drug release was observed with the BH-loaded nanoparticles in artificial tears (pH 7.4). The results of FT-IR, TG and XRD showed that the drug was coated with CSMMT/ TPP NPs. In the mucoadhesion studies, an interaction was found between drug-loaded CSMMT/ TPP NPs and mucin, which could enhance precorneal residence time and hence facilitate an effective sustained release. The optimized formulation was determined to be non-irritant and tolerable by modified Draize test. Therefore, the BH-loading CS-MMT/TPP NPs developed are a promising carrier for controlled drug delivery to the eye.展开更多
Oral insulin delivery has received the most attention in insulin formulations due to its high patient compliance and, more importantly, to its potential to mimic the physiologic insulin secretion seen in non-diabetic ...Oral insulin delivery has received the most attention in insulin formulations due to its high patient compliance and, more importantly, to its potential to mimic the physiologic insulin secretion seen in non-diabetic individuals. However, oral insulin delivery has two major limitations： the enzymatic barrier that leads to rapid insulin degradation, and the mucosal barrier that limits insulin＇s bioavailability. Several approaches have been actively pursued to circumvent the enzyme barrier, with some of them receiving promising results. Yet, thus far there has been no major success in overcoming the mucosal barrier, which is the main cause in undercutting insulin＇s oral bioavailability. In this review of our group＇s research, an innovative silica-based, mucoadhesive oral insulin formulation with encapsulated-insulin/cell penetrating peptide （CPP） to overcome both enzyme and mucosal barriers is discussed, and the preliminary and convincing results to confirm the plausibility of this oral insulin delivery system are reviewed. In vitro studies demonstrated that the CPPinsulin conjugates could facilitate cellular uptake of insulin while keeping insulin＇s biologic functions intact. It was also confirmed that low molecular weight protamine （LMWP） behaves like a CPP peptide, with a cell translocation potency equivalent to that of the widely studied TAT. The mucoadhesive properties of the produced silica-chitosan composites could be controlled by varying both the pH and composition; the composite consisting of chitosan （25wt-%） and silica （75 wt-%） exhibited the greatest mucoadhesion at gastric pH. Furthermore, drugrelease from the composite network could also be regulated by altering the chitosan content. Overall, the universal applicability of those technologies could lead to development of a generic platform for oral delivery of many other bioactive compounds, especially for peptide or protein drugs which inevitably encounter the poor bioavailability issues.展开更多
Mucins are vital components contributing to the unique lubrication properties of human whole saliva.For patients receiving medication and or treatment such as diabetes or radiotherapy,xerostomia(dry mouth)is a common ...Mucins are vital components contributing to the unique lubrication properties of human whole saliva.For patients receiving medication and or treatment such as diabetes or radiotherapy,xerostomia(dry mouth)is a common with numerous and deleterious side effects.Although products exist on the market to relive the symptoms of Xerostomia there remains a drive to formulate a biocompatible lubricant that replicate the functionality offered by the natural biological environment.Herein,a combination of mucin and thiolated polyethylene glycol(PEG-SH)was proposed as a new saliva substitute.Mucin and PEG-SH molecules could form hydrated layers immediately by chemisorption.Meanwhile,the chemical interactions between mucin and PEG-SH molecules also promoted the formation of a mixed layer.All the pre-formed layers could decrease friction and had the potential to decrease wear,especially mucin and PEG-SH mixed layer when compared to mucin only solutions.Further investigations of tribological mechanism implied that the excellent lubrication performance of mixed layer with long effectiveness was contributed to the frictionreducing effect of PEG/mucin molecules and the mucoadhesive property of mucin.The study provides a guide for using mucin as a mucoadhesive agent to stable lubricative polymers with low molecular weight as novel salivary substitutes for lubrication.展开更多
The efficacy of orally delivered medicines can be maximized through enhancing the gastric residence period and modifying the drug release pattern according to therapeutic need.Several technologies were investigated th...The efficacy of orally delivered medicines can be maximized through enhancing the gastric residence period and modifying the drug release pattern according to therapeutic need.Several technologies were investigated through recent years for increasing gastric retention of medicines.Biopolymers are one of the widely studied materials for increasing the retention of drug delivery systems in the stomach region.The biodegradability,biocompatibility and non-toxic behavior in combination with the easy fabrication technologies has made biopolymers an interesting option to pharmaceutical scientists for developing gastroretentive drug delivery systems(GRDDS).Several gastroretentive approaches are reported to be efficacious to localize the drug delivery system in the gastric region.Alginates are commonly employed polysaccharide for developing various GRDDS including low density systems,mucoadhesive systems,swellable systems,hydrogel forming systems,in situ gelling systems,raft forming systems,magnetic systems.The abundant availability from marine and bacterial sources in combination with its attractive physicochemical nature has encouraged pharmaceutical researchers to investigate its suitability in developing various drug delivery system.The mucoadhesive,hydrogel forming and raft forming behavior of alginates makes alginate suitable for GRDDS.The attractive properties of alginate makes it a useful biopolymer in the biomedical field.This review focuses on the source and chemistry of alginates and describes the applications of alginates in developing novel gastroretentive drug delivery systems.展开更多
Background and Objective: Several studies have shown the wound healing effect of topical phenytoin, which is applied by its effect on connective tissue intracellular matrix. However, there are still some controversies...Background and Objective: Several studies have shown the wound healing effect of topical phenytoin, which is applied by its effect on connective tissue intracellular matrix. However, there are still some controversies about its effect on various kinds of wounds, especially in the experimental models. This study is aimed at evaluating the effect of mucoadhesive paste compared to phenytoin mucoadhesive paste on wound healing after oral biopsy. Material and Methods: In this double blind randomized clinical trial, 20 patients who were eligible for oral biopsy were allocated into the case and control groups. After the biopsy, patients having ulcers ranging between one and two centimeters were treated by simple or 1% phenytoin mucoadhesive paste. All patients were instructed to apply their paste at least three times a day for five days after the biopsy. Patients in both groups were evaluated every other day for size of the ulcer, degree of pain and diameter of the inflammatory halo. Statistical analysis was done using SPSS software and Mann-Whitney test. Results: After the second and third appointments, it was observed that the rate of wound healing and decrease in the size of the ulcers were significantly quicker in the treatment group (p = 0.001 and p = 0.003 respectively) and the patients in the phenytoin group reported less pain. Diameter of the inflammatory halo was not significantly different between two groups. Conclusion: Applying 1% phenytoin mucoadhesive paste on biopsy ulcers resulted in accelerated wound healing and decrease in pain, but had no effect on the diameter of the inflammatory halo.展开更多
The aims of this study were to prepare and characterize hydroxypropyl methylcellulose(HPMC)/polycarbophil(PC) mucoadhesive blend films saturated with propranolol hydrochloride(PNL)-loaded nanoparticles to improve perm...The aims of this study were to prepare and characterize hydroxypropyl methylcellulose(HPMC)/polycarbophil(PC) mucoadhesive blend films saturated with propranolol hydrochloride(PNL)-loaded nanoparticles to improve permeability of drugs that undergo firstpass metabolism. An ionic cross-linking method and film casting technique was used to prepare nanoparticles and mucoadhesive blend films, respectively. Increasing concentrations of PNL(70, 80, 90 mg/film) in HPMC/PC blend films containing PNL-loaded nanoparticles(PN-films) and HPMC/PC blend films containing PNL(80 mg/film) without nanoparticles(PPfilms) were prepared to test swelling, mucoadhesiveness, release, permeation and physicochemical properties. Scanning electron microscope(SEM) images showed a partially smooth surface with a wrinkled occurrence and spherically shaped, well-dispersed nanoparticles on the surface of PN-films containing PNL 80 mg/film(PN-films-80). The size of the nanoparticles on the surface of PN-films-80 was around 100 nm, which was similar to the nanoparticle size observed using light scattering technique. The swelling index(SI)of all PN-films and PP-films increased greatly in the first period time(10–20 min) and reached swelling equilibrium at 20 min and 30 min, respectively. For the PN-films, the concentration of PNL influenced the mucoadhesive properties and tended to be higher when the amount of PNL increased. Immediate release of all blend film formulations was found in early time points(10–30 min). After 120 min, the release of PN-films-70 was lower than the other PNfilms. Permeation studies using porcine buccal mucosa showed that inclusion of nanoparticles in the films increased the permeability of PNL compared to PP-films. Therefore, buccal administration of mucoadhesive blend films containing PNL-loaded nanoparticles could be a promising approach for drugs that undergo first-pass metabolism.展开更多
Microspheres containing Pioglitazone hydrochloride were prepared by the ionotropic external gelation method, using sodium alginate with four mucoadhesive polymers namely sodium carboxy methyl cellulose, hydroxy propyl...Microspheres containing Pioglitazone hydrochloride were prepared by the ionotropic external gelation method, using sodium alginate with four mucoadhesive polymers namely sodium carboxy methyl cellulose, hydroxy propyl methyl cellulose, carbopol 934 P and cellulose acetate phthalate as coat materials. Ionotropic gelation is a method to prepare microspheres using combination of Ca<sup>2+</sup> as cationic components and alginate as anion. The practical yield of prepared microspheres using the ionotropic gelation technique was between 172 mg and 604 mg. The result of the Chi-squared test carried out between the actual (practical) and expected (theoretical) yields showed no significant difference (P < 0.05) which indicated that the ionotropic gelation technique could be successfully employed to prepare pioglitazone microspheres using sodium alginate, sodium carboxy methyl cellulose, carbopol 934 P, HPMC, cellulose acetate butyrate polymers. The drug entrapment efficiency of prepared microspheres showed between 56.12% ± 3.86% to 84.68% ± 2.93% which was significantly higher for ionotropic gelation technique. The highest drug entrapment was found in formulation PMI 8. Swelling index is the capability of a polymer to swell before the drug is released which influences the rate and mechanism of drug release from the polymer matrix. The swelling index of prepared microspheres was in the range of 68% ± 4.52% to 87% ± 0.98%. Pioglitazone HCl microspheres showed controlled release of drug without initial peak level achieving. This type of properties in Pioglitazone HCl microspheres used to decrease side effects, reduce dosing frequency and improve patient compliances. From the all batches PMI 8 is considered the best formulation, because among all other formulations, it shows better extent of drug release up to 82.12% (18 h), good entrapment efficiency (84.68%) and the ex-vivo wash-off test shows the best mucoadhesive property. The in vitro drug release studies do up to 18 h. As observed from the various plots, most of th展开更多
The aim of present study was to prepare buccal tablets of fluconazole for oral candidiasis.The dosage forms were designed to release the drug above the minimum inhibitory concentration for prolonged period of time so ...The aim of present study was to prepare buccal tablets of fluconazole for oral candidiasis.The dosage forms were designed to release the drug above the minimum inhibitory concentration for prolonged period of time so as to reduce the frequency of administration and to overcome the side effects of systemic treatment.The buccal tablets were prepared by using Carbopol 71G and Noveon AA-1 by direct compression method.Microcry stalline cellulose was used as the filler and its effect was also studied.The prepared dosage forms were evaluated for physicochemical properties,in vitro release studies and mucoadhesive properties using sheep buccal mucosa as a model tissue.Tablets containing 50% of polymers(Carbopol & Noveon) were found to be the best with moderate swelling along with favorable bioadhesion force,residence time and in vitro drug release.The in vitro drug release studies revealed that drug released for 8 h,which in turn may reduce dosing frequency and improved patient compliance in oral candidiasis patients.展开更多
Topical administration is the most common and acceptable use for the treatment of ocular disease.However,the major problem of ocular drug delivery is the rapid drug elimination from the pre-ocular area leading to poor...Topical administration is the most common and acceptable use for the treatment of ocular disease.However,the major problem of ocular drug delivery is the rapid drug elimination from the pre-ocular area leading to poor ocular bioavailability[1].Nanostructure lipid carriers(NLC)possess a significant enhancement in ocular bioavailability by increasing the permeability and mucoadhesive property[2].In this study,indomethacin(IND),non-steroidal anti-inflammatory,was used as a model drug[3].展开更多
Cashew gum is a branched chain heteropolysaccharide extracted from the cashew tree (Anacardium occidentale L.).Purified cashew gum (PCG) is free of plant contaminants and is highly soluble.Several studies have indicat...Cashew gum is a branched chain heteropolysaccharide extracted from the cashew tree (Anacardium occidentale L.).Purified cashew gum (PCG) is free of plant contaminants and is highly soluble.Several studies have indicated this polymer can be relevant in the pharmaceutical industry for production of tablets.Recently,our research group reported that PCG can be used as a diluent for tablets produced by direct compression.Nystatin (Nys) is the drug of first choice for treatment of oral candidiasis,in the form of a suspension.The treatment consists of up to six daily doses of a suspension of nys at 500,000 IU,causing low therapeutic adhesion by patients.The objective of this study was to investigate the behavior of PCG together with nys and other excipients (flavoring agents and lubricating agent) for future manufacture of mucoadhesive buccal tablets by direct compression.For that purpose,we performed pre-formulation tests (FTIR,TGA,XRD,solubility,pH,granulometry,swelling degree and powder flow) with physical mixtures of the drug and excipients.The results were excellent,demonstrating that PCG is a polymer with potential for this type of application.展开更多
This research work deals with formulation and evaluation of nanosized Tiagabine loaded bio-flexy films consisting of Cocos nucifera biopolymer(isolated from coconut kernels).Prepared formulations were administered thr...This research work deals with formulation and evaluation of nanosized Tiagabine loaded bio-flexy films consisting of Cocos nucifera biopolymer(isolated from coconut kernels).Prepared formulations were administered through soft palatal route for brain targeting for epilepsy treatment.Soft palate,part of oral mucosa serves as novel drug delivery platform and mucoadhesive site for systemic drug delivery.It provides sustained and controlled drug delivery system,does not interfere with patient’s regular activities like talking,eating,drinking,etc.It bypasses first-pass metabolism in the liver,reduces dose frequency and minimizes drug’s side effects.Tiagabine,anticonvulsant drug possesses t1/2:7-9 h(low);Protein binding:96%;Water solubility:22 mg/L,acts as selective gamma amino butyric acid(GABA)reuptake inhibitor.Cocos nucifera biopolymer used as bio-excipient to prepare bio-flexy films due to its biodegradability,biocompatibility,non-toxicity,non-irritantancy on soft palatal surface along with inbuilt filmability,mucoadhesive properties.Nanosized drug loaded bio-flexy films were formulated using standard solvent casting method.Bio-flexy films were prepared using varying ratios of nanosized Tiagabine:isolated Cocos nucifera biopolymer(FCT1-FCT6).These prepared formulations were compared with same ratios of nanosized Tiagabine:sodium carboxyl methyl cellulose standard polymer flexy films(FET1-FET6).The%yield of Cocos nucifera biopolymer was found to be 10.2±0.04%.Thickness of nanosized Tiagabine loaded bio-flexy films containing Cocos nucifera biopolymer(FCT1-FCT6)was ranging from 0.026±0.04 mm to 0.040±0.02 mm;Folding endurance:84-107;Surface pH:7.01±0.04 to 7.01±0.02;Weight uniformity:0.012±0.04 to 0.020±0.02;Drug content uniformity:69.5±0.35%to 72.9±0.26%;Swelling percentage:65±0.5%to 73±0.2%;Percentage moisture uptake(PTU):2.0±0.14%to 2.8±0.12%;Mucoadhesivity:20-90 min;Mucoretentivity:60-180 min.The drug release pattern for formulations FCT1-FCT6 containing Cocos nucifera biopolymer based on the T5展开更多
The present work compares and evaluates the suitability of different polymer-based microparticles for inhalation delivery of doxycycline hyclate.Mucoadhesive polymers,such as sodium carboxymethyl cellulose,sodium algi...The present work compares and evaluates the suitability of different polymer-based microparticles for inhalation delivery of doxycycline hyclate.Mucoadhesive polymers,such as sodium carboxymethyl cellulose,sodium alginate,polyvinyl alcohol,polyvinylpyrolidone,starch,and carbopol were selected as carriers for inhalation delivery.Microparticles were prepared by spray drying and evaluated in terms of yield,moisture content,morphology,tapped density,encapsulation efficiency,in vitro mucoadhesion,thermal properties and in vitro aerosolization performance.Additionally,the cytotoxicity of the microparticles on H1299 human alveolar cell line was examined.Smooth spherical to collapsed doughnut shaped particles were formed.They exhibited tap densities of 0.202-0.502 g/cm^(3) and mass median aerodynamic diameter of 3.746.54 um.Mucoadhesion was highest in case of carbopol-based microparticles.Drug release from these microparticles exhibited biphasic Fickian type of diffusion.Only at the highest concentration of microparticles(1 mg/mL)less than 90% cell viability was seen in DX loaded sodium alginate microparticles(DXSA,87.2%),starch microparticles(DXST,85.1%)and carbopol microparticles(DXCP,82.7%)preparations after 48 h of exposure to alveolar cells.The results clearly indicate that sodium carboxymethyl cellulose-based microparticles may serve as an ideal carrier for inhalation delivery of doxycycline hyclate.展开更多
基金Financial support from the China Natural Science Foundation(NSFC: 81573361 and 81102385)
文摘Lack of mucoadhesive properties is the major drawback to poloxamer 407(F127)-based in situ hydrogels for mucosal administration. The objective of the present study was to construct a novel mucoadhesive and thermosensitive in situ hydrogel drug delivery system based on an aminofunctionalized poloxamer for vaginal administration. First, amino-functionalized poloxamer 407(F127-NH2) was synthesized and characterized with respect to its micellization behavior and interaction with mucin. Then using acetate gossypol(AG) as model drug, AG-loaded F127-NH2-based in situ hydrogels(NFGs) were evaluated with respect to rheology, drug release, ex vivo vaginal mucosal adhesion, in vivo intravaginal retention and local irritation after vaginal administration to healthy female mice. The results show that F127-NH2 is capable of forming a thermosensitive in situ hydrogel with sustained drug release properties. An interaction between positively charged F127-NH2 and negatively charged mucin wasrevealed by changes in the particle size and zeta potential of mucin particles as well as an increase in the complex modulus of NFG caused by mucin. Ex vivo and in vivo fluorescence imaging and quantitative analysis of the amount of AG remaining in mouse vaginal lavage all demonstrated greater intravaginal retention of NFG than that of an unmodified F127-based in situ hydrogel. In conclusion, amino group functionalization confers valuable mucoadhesive properties on poloxamer 407.
文摘The objective of the study was to investigate the potential of montmorillonite as a sustained carrier in the preparation of drug-loaded nanoparticles for prolonged ocular application. Nanoparticles were prepared by ionic gelation of chitosan with sodium tripolyphosphate (TPP). Betaxolol hydrochloride (BH) was applied as a model drug. TG, FT-IR, TEM, DLS and XRD have been employed in the characterization of drug-encapsulated chitosan-montmorillonite/TPP nanoparticles (CS-MMT/TPP NPs). TEM images showed that the particles were spherical in shape and had a rough surface. The size range of the nanoparticles was between 338 and 585 nm with positive zeta potential values from 24 mV to 36 mV and encapsulation efficiency values ranging from 12.27% to 50.92%. In vitro sustained drug release was observed with the BH-loaded nanoparticles in artificial tears (pH 7.4). The results of FT-IR, TG and XRD showed that the drug was coated with CSMMT/ TPP NPs. In the mucoadhesion studies, an interaction was found between drug-loaded CSMMT/ TPP NPs and mucin, which could enhance precorneal residence time and hence facilitate an effective sustained release. The optimized formulation was determined to be non-irritant and tolerable by modified Draize test. Therefore, the BH-loading CS-MMT/TPP NPs developed are a promising carrier for controlled drug delivery to the eye.
文摘Oral insulin delivery has received the most attention in insulin formulations due to its high patient compliance and, more importantly, to its potential to mimic the physiologic insulin secretion seen in non-diabetic individuals. However, oral insulin delivery has two major limitations： the enzymatic barrier that leads to rapid insulin degradation, and the mucosal barrier that limits insulin＇s bioavailability. Several approaches have been actively pursued to circumvent the enzyme barrier, with some of them receiving promising results. Yet, thus far there has been no major success in overcoming the mucosal barrier, which is the main cause in undercutting insulin＇s oral bioavailability. In this review of our group＇s research, an innovative silica-based, mucoadhesive oral insulin formulation with encapsulated-insulin/cell penetrating peptide （CPP） to overcome both enzyme and mucosal barriers is discussed, and the preliminary and convincing results to confirm the plausibility of this oral insulin delivery system are reviewed. In vitro studies demonstrated that the CPPinsulin conjugates could facilitate cellular uptake of insulin while keeping insulin＇s biologic functions intact. It was also confirmed that low molecular weight protamine （LMWP） behaves like a CPP peptide, with a cell translocation potency equivalent to that of the widely studied TAT. The mucoadhesive properties of the produced silica-chitosan composites could be controlled by varying both the pH and composition; the composite consisting of chitosan （25wt-%） and silica （75 wt-%） exhibited the greatest mucoadhesion at gastric pH. Furthermore, drugrelease from the composite network could also be regulated by altering the chitosan content. Overall, the universal applicability of those technologies could lead to development of a generic platform for oral delivery of many other bioactive compounds, especially for peptide or protein drugs which inevitably encounter the poor bioavailability issues.
基金supported by the International Postdoctoral Exchange Fellowship Program(Grant No.20190060)。
文摘Mucins are vital components contributing to the unique lubrication properties of human whole saliva.For patients receiving medication and or treatment such as diabetes or radiotherapy,xerostomia(dry mouth)is a common with numerous and deleterious side effects.Although products exist on the market to relive the symptoms of Xerostomia there remains a drive to formulate a biocompatible lubricant that replicate the functionality offered by the natural biological environment.Herein,a combination of mucin and thiolated polyethylene glycol(PEG-SH)was proposed as a new saliva substitute.Mucin and PEG-SH molecules could form hydrated layers immediately by chemisorption.Meanwhile,the chemical interactions between mucin and PEG-SH molecules also promoted the formation of a mixed layer.All the pre-formed layers could decrease friction and had the potential to decrease wear,especially mucin and PEG-SH mixed layer when compared to mucin only solutions.Further investigations of tribological mechanism implied that the excellent lubrication performance of mixed layer with long effectiveness was contributed to the frictionreducing effect of PEG/mucin molecules and the mucoadhesive property of mucin.The study provides a guide for using mucin as a mucoadhesive agent to stable lubricative polymers with low molecular weight as novel salivary substitutes for lubrication.
文摘The efficacy of orally delivered medicines can be maximized through enhancing the gastric residence period and modifying the drug release pattern according to therapeutic need.Several technologies were investigated through recent years for increasing gastric retention of medicines.Biopolymers are one of the widely studied materials for increasing the retention of drug delivery systems in the stomach region.The biodegradability,biocompatibility and non-toxic behavior in combination with the easy fabrication technologies has made biopolymers an interesting option to pharmaceutical scientists for developing gastroretentive drug delivery systems(GRDDS).Several gastroretentive approaches are reported to be efficacious to localize the drug delivery system in the gastric region.Alginates are commonly employed polysaccharide for developing various GRDDS including low density systems,mucoadhesive systems,swellable systems,hydrogel forming systems,in situ gelling systems,raft forming systems,magnetic systems.The abundant availability from marine and bacterial sources in combination with its attractive physicochemical nature has encouraged pharmaceutical researchers to investigate its suitability in developing various drug delivery system.The mucoadhesive,hydrogel forming and raft forming behavior of alginates makes alginate suitable for GRDDS.The attractive properties of alginate makes it a useful biopolymer in the biomedical field.This review focuses on the source and chemistry of alginates and describes the applications of alginates in developing novel gastroretentive drug delivery systems.
文摘Background and Objective: Several studies have shown the wound healing effect of topical phenytoin, which is applied by its effect on connective tissue intracellular matrix. However, there are still some controversies about its effect on various kinds of wounds, especially in the experimental models. This study is aimed at evaluating the effect of mucoadhesive paste compared to phenytoin mucoadhesive paste on wound healing after oral biopsy. Material and Methods: In this double blind randomized clinical trial, 20 patients who were eligible for oral biopsy were allocated into the case and control groups. After the biopsy, patients having ulcers ranging between one and two centimeters were treated by simple or 1% phenytoin mucoadhesive paste. All patients were instructed to apply their paste at least three times a day for five days after the biopsy. Patients in both groups were evaluated every other day for size of the ulcer, degree of pain and diameter of the inflammatory halo. Statistical analysis was done using SPSS software and Mann-Whitney test. Results: After the second and third appointments, it was observed that the rate of wound healing and decrease in the size of the ulcers were significantly quicker in the treatment group (p = 0.001 and p = 0.003 respectively) and the patients in the phenytoin group reported less pain. Diameter of the inflammatory halo was not significantly different between two groups. Conclusion: Applying 1% phenytoin mucoadhesive paste on biopsy ulcers resulted in accelerated wound healing and decrease in pain, but had no effect on the diameter of the inflammatory halo.
基金the financial support provided by Thammasat University under the TU Research Scholar,Contract No.TP 2/68/2556
文摘The aims of this study were to prepare and characterize hydroxypropyl methylcellulose(HPMC)/polycarbophil(PC) mucoadhesive blend films saturated with propranolol hydrochloride(PNL)-loaded nanoparticles to improve permeability of drugs that undergo firstpass metabolism. An ionic cross-linking method and film casting technique was used to prepare nanoparticles and mucoadhesive blend films, respectively. Increasing concentrations of PNL(70, 80, 90 mg/film) in HPMC/PC blend films containing PNL-loaded nanoparticles(PN-films) and HPMC/PC blend films containing PNL(80 mg/film) without nanoparticles(PPfilms) were prepared to test swelling, mucoadhesiveness, release, permeation and physicochemical properties. Scanning electron microscope(SEM) images showed a partially smooth surface with a wrinkled occurrence and spherically shaped, well-dispersed nanoparticles on the surface of PN-films containing PNL 80 mg/film(PN-films-80). The size of the nanoparticles on the surface of PN-films-80 was around 100 nm, which was similar to the nanoparticle size observed using light scattering technique. The swelling index(SI)of all PN-films and PP-films increased greatly in the first period time(10–20 min) and reached swelling equilibrium at 20 min and 30 min, respectively. For the PN-films, the concentration of PNL influenced the mucoadhesive properties and tended to be higher when the amount of PNL increased. Immediate release of all blend film formulations was found in early time points(10–30 min). After 120 min, the release of PN-films-70 was lower than the other PNfilms. Permeation studies using porcine buccal mucosa showed that inclusion of nanoparticles in the films increased the permeability of PNL compared to PP-films. Therefore, buccal administration of mucoadhesive blend films containing PNL-loaded nanoparticles could be a promising approach for drugs that undergo first-pass metabolism.
文摘Microspheres containing Pioglitazone hydrochloride were prepared by the ionotropic external gelation method, using sodium alginate with four mucoadhesive polymers namely sodium carboxy methyl cellulose, hydroxy propyl methyl cellulose, carbopol 934 P and cellulose acetate phthalate as coat materials. Ionotropic gelation is a method to prepare microspheres using combination of Ca<sup>2+</sup> as cationic components and alginate as anion. The practical yield of prepared microspheres using the ionotropic gelation technique was between 172 mg and 604 mg. The result of the Chi-squared test carried out between the actual (practical) and expected (theoretical) yields showed no significant difference (P < 0.05) which indicated that the ionotropic gelation technique could be successfully employed to prepare pioglitazone microspheres using sodium alginate, sodium carboxy methyl cellulose, carbopol 934 P, HPMC, cellulose acetate butyrate polymers. The drug entrapment efficiency of prepared microspheres showed between 56.12% ± 3.86% to 84.68% ± 2.93% which was significantly higher for ionotropic gelation technique. The highest drug entrapment was found in formulation PMI 8. Swelling index is the capability of a polymer to swell before the drug is released which influences the rate and mechanism of drug release from the polymer matrix. The swelling index of prepared microspheres was in the range of 68% ± 4.52% to 87% ± 0.98%. Pioglitazone HCl microspheres showed controlled release of drug without initial peak level achieving. This type of properties in Pioglitazone HCl microspheres used to decrease side effects, reduce dosing frequency and improve patient compliances. From the all batches PMI 8 is considered the best formulation, because among all other formulations, it shows better extent of drug release up to 82.12% (18 h), good entrapment efficiency (84.68%) and the ex-vivo wash-off test shows the best mucoadhesive property. The in vitro drug release studies do up to 18 h. As observed from the various plots, most of th
文摘The aim of present study was to prepare buccal tablets of fluconazole for oral candidiasis.The dosage forms were designed to release the drug above the minimum inhibitory concentration for prolonged period of time so as to reduce the frequency of administration and to overcome the side effects of systemic treatment.The buccal tablets were prepared by using Carbopol 71G and Noveon AA-1 by direct compression method.Microcry stalline cellulose was used as the filler and its effect was also studied.The prepared dosage forms were evaluated for physicochemical properties,in vitro release studies and mucoadhesive properties using sheep buccal mucosa as a model tissue.Tablets containing 50% of polymers(Carbopol & Noveon) were found to be the best with moderate swelling along with favorable bioadhesion force,residence time and in vitro drug release.The in vitro drug release studies revealed that drug released for 8 h,which in turn may reduce dosing frequency and improved patient compliance in oral candidiasis patients.
文摘Topical administration is the most common and acceptable use for the treatment of ocular disease.However,the major problem of ocular drug delivery is the rapid drug elimination from the pre-ocular area leading to poor ocular bioavailability[1].Nanostructure lipid carriers(NLC)possess a significant enhancement in ocular bioavailability by increasing the permeability and mucoadhesive property[2].In this study,indomethacin(IND),non-steroidal anti-inflammatory,was used as a model drug[3].
文摘Cashew gum is a branched chain heteropolysaccharide extracted from the cashew tree (Anacardium occidentale L.).Purified cashew gum (PCG) is free of plant contaminants and is highly soluble.Several studies have indicated this polymer can be relevant in the pharmaceutical industry for production of tablets.Recently,our research group reported that PCG can be used as a diluent for tablets produced by direct compression.Nystatin (Nys) is the drug of first choice for treatment of oral candidiasis,in the form of a suspension.The treatment consists of up to six daily doses of a suspension of nys at 500,000 IU,causing low therapeutic adhesion by patients.The objective of this study was to investigate the behavior of PCG together with nys and other excipients (flavoring agents and lubricating agent) for future manufacture of mucoadhesive buccal tablets by direct compression.For that purpose,we performed pre-formulation tests (FTIR,TGA,XRD,solubility,pH,granulometry,swelling degree and powder flow) with physical mixtures of the drug and excipients.The results were excellent,demonstrating that PCG is a polymer with potential for this type of application.
文摘This research work deals with formulation and evaluation of nanosized Tiagabine loaded bio-flexy films consisting of Cocos nucifera biopolymer(isolated from coconut kernels).Prepared formulations were administered through soft palatal route for brain targeting for epilepsy treatment.Soft palate,part of oral mucosa serves as novel drug delivery platform and mucoadhesive site for systemic drug delivery.It provides sustained and controlled drug delivery system,does not interfere with patient’s regular activities like talking,eating,drinking,etc.It bypasses first-pass metabolism in the liver,reduces dose frequency and minimizes drug’s side effects.Tiagabine,anticonvulsant drug possesses t1/2:7-9 h(low);Protein binding:96%;Water solubility:22 mg/L,acts as selective gamma amino butyric acid(GABA)reuptake inhibitor.Cocos nucifera biopolymer used as bio-excipient to prepare bio-flexy films due to its biodegradability,biocompatibility,non-toxicity,non-irritantancy on soft palatal surface along with inbuilt filmability,mucoadhesive properties.Nanosized drug loaded bio-flexy films were formulated using standard solvent casting method.Bio-flexy films were prepared using varying ratios of nanosized Tiagabine:isolated Cocos nucifera biopolymer(FCT1-FCT6).These prepared formulations were compared with same ratios of nanosized Tiagabine:sodium carboxyl methyl cellulose standard polymer flexy films(FET1-FET6).The%yield of Cocos nucifera biopolymer was found to be 10.2±0.04%.Thickness of nanosized Tiagabine loaded bio-flexy films containing Cocos nucifera biopolymer(FCT1-FCT6)was ranging from 0.026±0.04 mm to 0.040±0.02 mm;Folding endurance:84-107;Surface pH:7.01±0.04 to 7.01±0.02;Weight uniformity:0.012±0.04 to 0.020±0.02;Drug content uniformity:69.5±0.35%to 72.9±0.26%;Swelling percentage:65±0.5%to 73±0.2%;Percentage moisture uptake(PTU):2.0±0.14%to 2.8±0.12%;Mucoadhesivity:20-90 min;Mucoretentivity:60-180 min.The drug release pattern for formulations FCT1-FCT6 containing Cocos nucifera biopolymer based on the T5
文摘The present work compares and evaluates the suitability of different polymer-based microparticles for inhalation delivery of doxycycline hyclate.Mucoadhesive polymers,such as sodium carboxymethyl cellulose,sodium alginate,polyvinyl alcohol,polyvinylpyrolidone,starch,and carbopol were selected as carriers for inhalation delivery.Microparticles were prepared by spray drying and evaluated in terms of yield,moisture content,morphology,tapped density,encapsulation efficiency,in vitro mucoadhesion,thermal properties and in vitro aerosolization performance.Additionally,the cytotoxicity of the microparticles on H1299 human alveolar cell line was examined.Smooth spherical to collapsed doughnut shaped particles were formed.They exhibited tap densities of 0.202-0.502 g/cm^(3) and mass median aerodynamic diameter of 3.746.54 um.Mucoadhesion was highest in case of carbopol-based microparticles.Drug release from these microparticles exhibited biphasic Fickian type of diffusion.Only at the highest concentration of microparticles(1 mg/mL)less than 90% cell viability was seen in DX loaded sodium alginate microparticles(DXSA,87.2%),starch microparticles(DXST,85.1%)and carbopol microparticles(DXCP,82.7%)preparations after 48 h of exposure to alveolar cells.The results clearly indicate that sodium carboxymethyl cellulose-based microparticles may serve as an ideal carrier for inhalation delivery of doxycycline hyclate.
