Formulation and Evaluation of Rizatriptan Benzoate Mouth Disintegrating Tablets

The present investigation deals with development of mouth disintegrating tablets of rizatriptan benzoate to produce the intended benefits. Mouth disintegrating tablets of rizatriptan benzoate were prepared using superdisintegrants crospovidone, carboxymethylcellulose calcium, Indion 414 and Indion 234 using the direct compression method. The tablets prepared were evaluated for thickness, uniformity of weight, content uniformity, hardness, friability, wetting time, in vitro and in vivo disintegration time, mouth feel, in vitro drug release and assay by high performance liquid chromatography. The tablets disintegrated in vitro and in vivo within 4 to 7 s and 6 to 19 s, respectively. Almost 90% of drug was released from all formulations within 20 min. The drug release from the formulations followed first order kinetics. Stability studies of the tablets at 40±2°/75%±5% RH for 1 mo showed non significant drug loss. The formulation containing combination of crospovidone and Indion 234 was found to give the best results. Apart from fulfilling all official and other specifications, the tablets exhibited higher rate of release.     

Formulation and Evaluation of Alstonia boonei Stem Bark Powder Tablets

The aim of this work was to formulate Alstonia boonei dried stem bark powder into tablets by wet granulation method using acacia, gelatine and sodium carboxymethyl cellulose as binders at concentrations of 1, 2, 4 and 8% w/w. The phytochemistry of the stem bark of Alstonia boonei was evaluated. The micromeritic properties of the granules prepared were studied. The tablets were evaluated using the necessary official and unofficial tests. The results of the phytochemical analysis showed that alkaloids, tannins, steroids, saponins, glycosides, flavonoids and terpenoids were present while anthroquinones and acidcompounds were absent. Micromeritic studies showed that Alstonia boonei granules had good flowability. The formulated tablets complied with British Pharmacopoeial specification for weight uniformity, hardness (≥5 kgf) and tablet friability (<1%). For disintegration test, tablets formulated with gelatine and acacia at concentrations of 1, 2 and 4% w/w complied with Pharmacopoeial specification. However, tablets formulated with SCMC (1-8% w/w) and 8% w/w of acacia and gelatine failed the disintegration tests (Disintegration time more than 15 min).     

荜茇提取物中5个生物碱的含量测定与对垂体后叶素所致大鼠实验性心肌缺血的影响

目的 建立荜茇提取物中5个生物碱含量测定方法,并评估该提取物对垂体后叶素所致大鼠实验性心肌缺血的影响。方法 采用HPLC法同时测定5个生物碱的含量;采用经舌下静脉注射垂体后叶素造成急性心肌缺血模型,以造模前后T波变化绝对值、心率及其变化百分率为观测指标,评估荜茇提取物大、中、小三个剂量组对大鼠实验性心肌缺血的影响。结果 3批荜茇提取物中胡椒碱平均含量为56.1%、49.7%、51.6%;N-异丁基-2E,4E-十八烷二烯酰胺平均含量为4.48%、4.21%、4.28%;几内亚胡椒碱平均含量为0.461%、0.378%、0.396%;荜茇明碱平均含量为1.73%、1.67%、1.70%;胡椒酰胺平均含量为0.554%、0.461%、0.493%。荜茇提取物大、中、小剂量组均有降低T波变化绝对值的作用;除大剂量组在个别时间点有降低心率的作用之外,其它各实验组在各时间点对心率变化率无显著影响。结论 所建立的生物碱含量测定分析方法可准确测定荜茇提取物中5个生物碱的含量;药效试验证明荜茇提取物具有较好的抗心肌缺血活性。     

Formulation Design and Optimization of Orodispersible Tablets of Quetiapine Fumarate by Sublimation Method

The objective of present study was to formulate directly compressible orodispersible tablets of quetiapine fumarate by sublimation method with a view to enhance patient compliance. A full 3² factorial design was used to investigate the effect of two variables viz., concentration of Indion 414 and camphor. Indion 414 (3-5 % w/w) was used as superdisintegrant and camphor (5-15 % w/w) as subliming agent. The tablets were evaluated for thickness, weight variation, hardness, friability, content uniformity, wetting time, porosity, in vitro disintegration time and in vitro drug release. The formulation containing 5% w/w of Indion 414 and 5% w/w camphor was emerged as promising based on evaluation parameters. The disintegration time for optimized formulation was 18.66 s. The tablet surface was evaluated for presence of pores by scanning electron microscopy before and after sublimation. Differential scanning colorimetric study did not indicate any drug excipient incompatibility, either during mixing or after compression. The effect of independent variables on disintegration time, % drug release and friability is presented graphically by surface response plots. Short-term stability studies on the optimized formulation indicated no significant changes in drug content and in vitro disintegration time. The directly compressible orodispersible tablets of quetiapine fumarate with lower friability, greater drug release and shorter disintegration times were obtained using Indion 414 and camphor at optimum concentrations.     

近红外光谱法鉴别普伐他汀钠片及其原料药晶型的一致性研究

目的 建立全覆盖抽样的普伐他汀钠片的近红外光谱法一致性检验模型,考察制剂工艺的差别和原料药晶型的差异,通过稳健、准确、代表性强的近红外光谱一致性模型实现普伐他汀钠片的快速检验和筛查。方法 对评价性抽验抽取的5个企业中的4个共65批样品建立普伐他汀钠片近红外一致性检验模型,并对4个厂家的原料药的近红外光谱图进行比较。结果 建立了4个厂家普伐他汀钠片剂的近红外一致性模型,预测成功率均为100%;4种原料药和1种无定型粉末的近红外光谱图显示不同晶型光谱图具有差异。结论 近红外光谱法能够用于快速鉴别质量工艺稳定的普伐他汀钠片产品,对制剂工艺进行考察,并能够区分不同晶型的原料药。     

Plantago ovata Mucilage in the Design of Fast Disintegrating Tablets

In the present work, fast disintegrating tablets of prochlorperazine maleate were designed with a view to enhance patient compliance by direct compression method. In this method mucilage of Plantago ovata and crospovidone were used as superdisintegrants (2-8% w/w) along with microcrystalline cellulose (20-60% w/w) and directly compressible mannitol (Pearlitol SD 200) to enhance mouth feel. The prepared batches of tablets were evaluated for hardness, friability, drug content uniformity, wetting time, water absorption ratio and in vitro dispersion time. Based on in vitro dispersion time (approximately 8 s), the two formulations were tested for the in vitro drug release pattern (in pH 6.8 phosphate buffer), short-term stability (at 40°/75% relative humidity for 3 mo) and drug-excipient interaction (IR spectroscopy). Among the two promising formulations, the formulation prepared by using 8% w/w of Plantago ovata mucilage and 60% w/w of microcrystalline cellulose emerged as the overall best formulation (t_50% 3.3 min) based on the in vitro drug release characteristics compared to conventional commercial tablets formulation (t_50% 17.4 min). Short-term stability studies on the formulations indicated that there are no significant changes in drug content and in vitro dispersion time (p<0.05).     

博落回总碱胃漂浮片的研制及体外释放的研究

目的:研制博落回总碱胃漂浮片,考察其漂浮和释药性能。方法:湿法压片制得博落回总碱胃漂浮片,并用HPLC检测博落回总碱在人工胃液中的释放量。结果:博落回总碱胃漂浮片的起漂时间小于3min持续漂浮时间大于12h,12h的累积释药量大于90%,释药行为符合Higuchi方程,释药机制为非Fickian扩散。结论:研制的博落回总碱胃漂浮片具有良好的漂浮性能和释药特性。     

Development of Solid SEDDS,V: Compaction and Drug Release Properties of Tablets Prepared by Adsorbing Lipid-Based Formulations onto Neusilin® US2

Purpose

To develop tablet formulations by adsorbing liquid self-emulsifying drug delivery systems (SEDDS) onto Neusilin®US2, a porous silicate.

Methods

Nine SEDDS were prepared by combining a medium chain monoglyceride, Capmul MCM EP, a medium chain triglyceride, Captex 355 EP/NF, or their mixtures with a surfactant Cremophor EL, and a model drug, probucol, was then dissolved. The solutions were directly adsorbed onto Neusilin®US2 at 1:1 w/w ratio. Content uniformity, bulk and tap density, compressibility index, Hausner ratio and angle of repose of the powders formed were determined. The powders were then compressed into tablets. The dispersion of SEDDS from tablets was studied in 250 mL of 0.01NHCl (USP dissolution apparatus; 50 RPM; 37°C) and compared with that of liquid SEDDS.

Results

After adsorption of liquid SEDDS onto Neusilin®US2, all powders demonstrated acceptable flow properties and content uniformity for development into tablet. Tablets with good tensile strength (>1 MPa) at the compression pressure of 45 to 135 MPa were obtained. Complete drug release from tablets was observed if the SEDDS did not form gels in contact with water; the gel formation clogged pores of the silicate and trapped the liquid inside pores.

Conclusion

Liquid SEDDS were successfully developed into tablets by adsorbing them onto Neusilin®US2. Complete drug release from tablets could be obtained.

     

Pharmacognostic and antifungal investigations of Elaeocarpus ganitrus (Rudrakasha)

Rudrakasha is the dried bead obtained from the ripe fruit of Elaeocarpus ganitrus Roxb. (Family: Elaeocarpaceae). Microscopic studies revealed the presence of a hard endocarp with lignified isodiametric sclereids, seeds with membranous seed coat, which enclosed a dense cellular endosperm comprising of calcium oxalate druses. Physicochemical parameters showed that total ash was 1.36 times and 1.56 times more than the acid insoluble ash and water-soluble ash, respectively. Further, ethanol had a maximum extractable value of 2.4% and moisture content was found to be 9.7%. Different extracts, petroleum ether, chloroform, ethanol and water were prepared. Chemically the extracts showed the presence of phytosterols, fats, alkaloids, flavonoids, carbohydrates, proteins and tannins. The extracts were evaluated for antifungal activity on different fungal strains. Chlorofom and ethanol extracts have high antifungal activity against Candida albicans. Whereas, chloroform, ethanol and water extracts showed moderate inhibition against Aspergillus niger.     

Poly(dl-lactic acid) as a direct compression excipient in controlled release tablets: Part I. Compaction behaviour and release characteristics of poly(dl-lactic acid) matrix tablets

High-molecular weight poly(dl-lactic acid) (PDLA, M_v 85 000) was applied as a direct compression excipient in controlled release tablets. PDLA powders with good flowing properties were obtained by milling pre-cooled PDLA granules. Apparent yield pressure values ranged from 44 to 71 MPa for tabletting speeds of 0.033 and 300 mm/s, respectively, pointing to a high ductility and limited strain rate sensitivity. Tablets with good mechanical strength (tensile strength 2.5–3.7 MPa) were prepared at different compaction speeds. Dissolution experiments with different drugs showed that PDLA exhibited good sustained release properties. Initial tablet porosity, lubrication with magnesium stearate and pH of the dissolution medium hardly affected the release rate of the incorporated drug. Drug loads, however, markedly affected the release rate. For drug loads between 20 and 50% w/w, a constant fractional release rate was found. Upon further decreasing of the drug load, the release rate was found to increase. This remarkable finding was explained by the rapid and large increase of the pore volume of the tablets. The results show the unique properties of PDLA and its suitability to be applied as a direct compression and release controlling excipient in matrix tablets for oral drug administration.     

Resolving Issues of Content Uniformity and Low Permeability Using Eutectic Blend of Camphor and Menthol

The aim of present study were to arrest the problem of content uniformity without the use of harmful organic solvent and to improve ex vivo permeability of captopril, a low dose class III drug as per biological classification system. Eutectic mixture of camphor and menthol was innovatively used in the work. Captopril solution in eutectic mixture was blended with Avicel PH 102 and then the mixture was blended with mannitol in different ratios. Formulated batches were characterized for angle of repose and Carr''s index. A selected batch was filled in hard gelatin capsule. Tablet dosage form was also developed. Capsules and tablets were characterized for in vitro drug release in 0.1N HCl. Additionally, the captopril tablets were analyzed for content uniformity and ex vivo drug permeation study using rat ileum in modified apparatus. The measurement of angle of repose and Carr''s index revealed that the powder blend exhibited good flow property and compressibility. The captopril capsules and tablets exhibited immediate drug release in 0.1 N HCl. The captopril tablets passed content uniformity test as per IP 1996. Ex vivo permeation of captopril, formulated with eutectic mixture, was faster than control. The permeation was increased by 15% at the end of 3 h. Tablets and capsule exhibited reasonable short term stability with no considerable change in performance characteristics.     

Formulation Design of Fast Disintegrating Tablets Using Disintegrant Blends

In the present work, fast disintegrating tablets of prochlorperazine maleate were designed with a view to enhance patient compliance by direct compression method. In this method, crospovidone (up to 3% w/w) and croscarmellose sodium (up to 5% w/w) in combination were used as superdisintegrants. Since disintegrants complement each other, accelerating the disintegration process when used together. Estimation of prochlorperazine maleate in the prepared tablet formulations was carried out by extracting the drug with methanol and measuring the absorbance at 254.5nm. The prepared formulations were further evaluated for hardness, friability, drug content uniformity, in vitro dispersion time, wetting time and water absorption ratio. Based on in vitro dispersion time (approximately 12 s), one promising formulation was tested for in vitro drug release pattern in phosphate buffer pH 6.8 and short-term stability (at 40°/70% RH for 3 mo), drug-excipient interaction (IR spectroscopy) were studied. Among the formulations tested, formulation DCPC₄ containing 5% w/w of croscarmellose sodium and 3% w/w of crospovidone as superdisintegrant emerged as the overall best (t_50% 7.0 min) based on drug release characteristics in pH 6.8 phosphate buffer compared to commercial conventional tablet formulation (t_50% 17.4 min). Short-term stability studies on the promising formulation indicated that there were no significant changes in drug content and in vitro dispersion time (p<0.05).     

Studies on Formulation and In Vitro Evaluation of Floating Matrix Tablets of Domperidone

Floating matrix tablets of domperidone were developed to prolong gastric residence time and thereby increased drug bioavailability. Domperidone was chosen as a model drug because it is poorly absorbed from the lower gastrointestinal tract. The tablets were prepared by wet granulation technique, using polymers such as hydroxypropylmethylcellulose K4M, carbopol 934P, and sodium alginate, either alone or in combination, and other standard excipients. Tablets were evaluated for physical characteristics viz. hardness, % friability, floating capacity, weight variation and content uniformity. Further, tablets were evaluated for in vitro release characteristics for 24 h. In vitro release mechanism was evaluated by linear regression analysis. Floating matrix tablets based on combination of three polymers namely; hydroxypropylmethylcellulose K4M, carbopol 934P and sodium alginate exhibited desired floating and prolonged drug release for 24 h. Carbopol loading showed negative effect on floating properties but were found helpful to control the release rate of drug.     

Evaluation of Gum of Moringa oleifera as a Binder and Release Retardant in Tablet Formulation

The present study was undertaken to find out the potential of gum from Moringa oleifera to act as a binder and release retardant in tablet formulations. The effect of calcium sulphate dihydrate (water insoluble) and lactose (water soluble) diluent on the release of propranolol hydrochloride was studied. The DSC thermograms of drug, gum and mixture of gum/drug indicated no chemical interaction. Tablets (F1, F2, F3, and F4) were prepared containing calcium sulphate dihydrate as diluent, propranolol hydrochloride as model drug using 10%, 8%, 6% and 4% w/v of gum solution as binder. Magnesium stearate was used as lubricant. Physical and technological properties of granules and tablets like flow rate, Carr index, Hausner ratio, angle of repose, hardness, friability and disintegration time were determined and found to be satisfactory. Tablets were prepared by wet granulation method containing calcium sulphate dihydrate as excipient, propranolol hydrochloride as model drug using 10%, 20% and 30% of gum as release retardant, magnesium stearate was used as lubricant. Similarly tablets were prepared replacing lactose with calcium sulphate dihydrate. Despite of the widely varying physico-chemical characteristics of the excipients, the drug release profiles were found to be similar. The drug release increased with increasing proportions of the excipient and decreased proportion of the gum irrespective of the solubility characteristics of the excipient. The values of release exponent 'n' are between 0.37 and 0.54. This implies that the release mechanism is Fickian. There is no evidence that the dissolution or erosion of the excipient has got any effect on the release of the drug. The t(50%) values for tablets containing calcium sulphate dihydrate were on an average 10%-15% longer than the tablets containing lactose as excipient. These relatively small differences in t(50%) values suggest that the nature of excipient used appeared to play a minor role in regulating the release, while the gum content was a major factor.     

Floating matrix dosage form for dextromethorphan hydrobromide based on gas forming technique: In vitro and in vivo evaluation in healthy volunteers

The objective of this study was to develop the dextromethorphan hydrobromide sustained-release (DMB-SR) tablets using floating technique to prolong the gastric residence time and compared their pharmacokinetic behavior with conventional sustained release tablets. DMB-SR floating tablets were prepared employing hydroxypropyl methylcellulose (HPMC) as hydrophilic gel material, sodium bicarbonate as gas-generating agent and hexadecanol as floating assistant agent. An orthogonal experiment design method was used to select the optimized formulation. The floating tablets were evaluated for uniformity of weight, hardness, friability, drug content, floating characteristics, in vitro release and in vivo bioavailability. The optimized tablets were prepared with HPMC K4M 25 mg, sodium bicarbonate 20 mg and hexadecanol 18 mg. The prepared tablets could float within 3 min and maintain for more than 24 h. The data of physical parameters were all lie within the limits. Drug release at 12 h was more than 85%. The comparative pharmacokinetic study was performed by administration of the DMB-SR floating tablets and conventional DMB-SR tablets. The area under curve of plasma concentration–time (AUC) of floating tablets was slightly higher than that of reference tablets, T_max was prolonged apparently. The results showed the floating tablets are a feasible approach for the sustained-release preparation of drugs, which have limited absorption sites in the stomach.     

Paralytic effect of alcoholic extract of Allium sativum and Piper longum on liver amphistome, Gigantocotyle explanatum

Objective:

To investigate the effects of alcoholic extract of Allium sativum and Piper longum on the muscular activity of a parasitic amphistome, Gigantocotyle explanatum.

Materials and Methods:

Amphistomes were isometrically mounted to record the spontaneous muscular activity by using Chart 4 software program (Power Lab, AD Instruments, Australia) and to examine the effects of cumulative doses (100, 300, 1000, and 3000 μg/ml) of the plant extracts on the amplitude (g), frequency (per 10 min), and baseline tension (g) of the spontaneous muscular activity of the amphistome.

Results:

Alcoholic extract of A. sativum produced significant reduction in the frequency and amplitude of contractile activity of the amphistome at 1000 and 3000 μg/ml bath concentrations. Complete paralysis of the amphistome was observed after 15 min of addition of 3000 μg/ml concentration. Alcoholic extract of P. longum also caused paralysis following 15-20 min exposure of the amphistome to 3000 μg/ml concentration. In both the cases the amphistomes did not recover from paralysis following 2-3 washes.

Conclusion:

The observations demonstrate the paralytic effect of alcoholic extract of A. sativum and P. longum on G. explanatum.     

Lysozyme Mucoadhesive Tablets Obtained by Freeze-Drying

Lysozyme is particularly attractive for the local treatment of oral pathologies related to microbiological infections. However, the requirement of a prolonged release is difficult to achieve because of saliva swallowing and of the protein denaturation which can occur during production and storage of a dosage form. This work demonstrates the feasibility to prepare lysozyme mucoadhesive tablets by freeze-drying. Tablets were prepared by using alginate (ALG) physically “cross-linked” with calcium ion and different grades of hydroxypropyl methylcellulose (HPMC) (i.e., E5, E50, or K100). The tablets were characterized in terms of swelling or erosion behavior, in vitro mucoadhesive properties, lysozyme activity (Micrococcus lysodeikticus), drug release and ability to inactivate Staphylococcus aureus. The formulations prepared with HPMC K100 were discarded because of the fast erosion. All other formulations allowed a sustained release over at least 6 h. Independently of composition, lysozyme activity (78,311 ± 1873 Units/mg) significantly decreased in the case of tablets containing 5% and 10% w/w of protein (55,000 Units/mg and 33,000 Units/mg, respectively). Conversely, no modifications occurred in the case of tablets containing 1% w/w lysozyme. The formulation prepared by ALG/HPMC E5 7/3 ratio was efficacious against S. aureus. After 3 months of storage at 5 ± 3°C, no significant decrease in lysozyme activity was observed.     

粉体学性质对替米沙坦氨氯地平双层片制备的影响

目的考察粉体学性质对替米沙坦氨氯地平双层片制备的影响。方法选择苯磺酸氨氯地平、替米沙坦以固定剂量组成的复方制剂为研究对象。从粉体学角度考察了粒度分布、休止角、堆密度、固密度等对双层片剂可压性、流动性和成型性的影响。结果湿法制粒筛网目数对氨氯地平层颗粒粉体学参数影响显著,随着制粒目数增加,休止角明显减小,固密度和压缩度明显增大,含量均一性增加,片质量差异减小;粉末直接压片工艺与湿法40目筛制粒得到氨氯地平层的颗粒的粒度分布基本一致。结论替米沙坦氨氯地平双层片的制备中各层物料的粉体学性质会影响制剂的成型性和含量均一性。     

Effects of drying methods on the physicochemical and compressional characteristics of Okra powder and the release properties of its metronidazole tablet formulation

A study has been made of the effects of sun and oven drying methods on the physicochemical characteristics and compressibility of Okra powder and the release properties of its metronidazole tablet formulation. Corn starch was used as the reference standard. The mechanical properties of the tablets were evaluated using crushing strength and friability, while the release properties were determined using the disintegration times and dissolution rates. The results obtained showed that sun-dried Okra powder had smaller particle size, exhibited good flow and possessed higher hydration and swelling capacities compared to the oven dried samples. The compressibility of Okra powders assessed by the indices of plasticity from Heckel (Py) and Kawakita plots (Pk) showed that sun dried Okra powders had higher Py but lower Pk values than the oven-dried Okra powder. Metronidazole tablets formulated with oven dried Okra powder formed stronger tablets than tablets containing sun dried Okra powder. Generally, tablets containing sun dried Okra powders had faster disintegration and dissolution than tablets formulated with oven-dried powder. The results suggest that the choice of drying method during the processing of pharmaceutical raw materials is critical to its physicochemical properties and the release properties of its tablet formulations.     

Effect of drug proportion and mixing time on the content uniformity of a low dose drug in a high shear mixer

The purpose of this study was to investigate the effect of reducing drug proportion and mixing time on the content uniformity of a low dose drug. Buspirone hydrochloride was used as a model drug and was mixed with other ingredients in two different concentrations (0.5% w/w and 5% w/w) in a T. K. Fielder high shear mixer at a high impeller speed (522 rpm) and a high chopper speed (3600 rpm) up to 32 min. Samples were withdrawn from nine locations in the mixer at specific time points using a side-sampling thief probe. The final blends at 32 min were compressed using an instrumented tablet press. Tablets were sampled at the beginning, middle, and end of the compression run. The statistical results indicated that the drug proportion had a significant effect on the content uniformity of the powder blend and the corresponding tablets. For this study, the optimum time to mix the 0.5% w/w formulation was after 8 min while it was only 1 min for the 5% w/w formulation. The RSD of buspirone hydrochloride contents of tablets decreased as the compression run was toward its end. Uniformly mixed blends produced tablets that met the USP XXIV content uniformity requirements.