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Ritonavir, exhibits low and variable oral bioavailability due to its poor aqueous solubility. Its oral absorption is dissolution rate limited and it requires enhancement in the solubility and dissolution rate for increasing its oral bioavailability. The individual main and combined  (interaction) effects of CDs and Solutol HS15 on the dissolution rate of  ritonavir from tablet formulations was investigated in a series of 22 – factorial experiments. Ritonavir (100mg) formulated in to compressed tablets by wet granulation method employing selected combinations of CDs ( βCD and HPβCD ) and Solutol HS15. All the tablets prepared were of good quality fulfilling the official (I.P) standards with regard to hardness, friability, disintegration time and drug content. Drug dissolution from the tablets formulated followed first order kinetics and gave relatively higher rates of dissolution (K1) and dissolution efficiency (DE30) values when compared to those of ritonavir plain tablets. Formulations R4 and R8, gave much higher dissolution rates when compared to plain tablets, R1. A 21.35 and 16.85 fold increase in K1 was observed respectively with formulations R4 and R8 when compared to formulation R1 (plain tablets). The dissolution efficiency (DE30) was also increased from 7.29% for formulation R1 (plain tablets) to  43.32 % and 39.36 % respectively for formulations R4 and R8. In combination βCD-Solutol HS15 gave 21.35 fold increase in the dissolution rate HPβCD and Solutol HS15 alone gave an enhancement of 4.85 fold and 6.10 fold in the dissolution rate (K1) of ritonavir tablets respectively. Whereas in combination, HPβCD and Solutol HS15 gave a 16.85 fold increase in the dissolution rate.

The objective of this study was to develop pH independent immediate release (IR) tablet formulation of Glipizide (GPZ) incorporating β-cyclodextrin (β-CD) and a ternary agent produced by high energy air jet milling complexation technique. GPZ (pKa of 5.9) is poorly water soluble (3.9µgm/ml) exhibiting pH dependent solubility (1.1µgm/ml at pH 2.0 and 26.6 µgm/ml at pH 6.8) owing to which it demonstrates dissolution rate limited absorption and bioavailability. Several complexation techniques involving formation of binary and ternary complexes were evaluated for achieving pH independent release of GPZ. Ternary complex involving GPZ:β-CD: Arginine (1:2:1) prepared using high energy air jet milling was found to be most promising in terms of significant enhancement in solubility, further attaining pH independent dissolution. Molecular modelling (MM) was carried out in order to understand the GPZ:β-CD orientation and GPZ group interactions with the cyclodextrin cavities. Molecular modelling suggested interaction of cyclohexyl and methylpyrazinecarboxamido groups of GPZ with the cyclodextrin cavities and favorability of head to tell (HT) orientation due to its minimum interaction energy. XRD and DSC study showed partial amorphization of GPZ. Scanning electron microscopy (SEM) studies revealed formation of new solid phase of ternary complex indicating partial amorphization. Tablets prepared using optimized ternary complex of GPZ showed immediate and pH independent drug release as compared to marketed tablet formulation and plain drug.

Alleles A1 and A2 of the Bos taurus CSN2 gene are the most common in a number of dairy cattle breeds. A genetic variant of the bovine β-casein gene includes A1 and B which encodes a histidine residue at codon 67, resulting in potential liberation of a bioactive peptide, β-casomorphin, upon digestion. This is an opium family substance, and has been associated with a large number of clinical implications in humans. Study includes amplification of bovine β-casein gene and further differentiation of variants A1 and A2 beta casein in cows. Conventional PCR was done to amplify β-casein gene in three hundred and one specimens. Further eighty amplicons were sent for sequencing. From the sequenced data, 24 were A2 homozygous (A2A2), 11were A1 homozygous (A1A1) and 37 heterozygous (A1A2). Allele discrimination in cows will be significant for the farmers, breeding programmes as well as for dairy industries as the milk variant determination will predict the outcome of the beta casein variants which are of utmost clinical relevance.

Alzheimer’s disease is the most prevalent form of dementia. Neuropathogenesis is proposed to be a result of the accumulation of amyloid β- peptides in the brain together with oxidative stress mechanisms and neuroinflammation. Drugs effective in Alzheimer’s disease (AD) should have several aims: to improve the cognitive impairment, control the behavioral and neurological symptoms, delay the progression of the disease, and prevent the onset. This review discusses the molecular mechanism of Alzheimer’s disease with a focus on the different agents those are inhibit the progression of the disease and improved patients condition and status.. Key words: Alzheimer’s disease, β-amyloid, Tacrine, Rivastigmine

Lornoxicam is comparatively a new non-steroidal anti-inflammatory drug, which is selective cyclooxygenase-1 and 2 (COX 1 and 2) inhibitors. Lornoxicam is a non steroidal anti-inflammatory drug that exhibits its anti inflammatory, analgesic and anti pyretic activities in animal models and it is presently available in the market only as tablet dosage form. It is preferred in the treatment of adults with osteoarthritis, acute pain rheumatoid arthritis, postoperative dental pain and primary dysmenorrhoea. The present study was undertaken with an intention to develop a stable and effective parenteral formulation, containing the drug Lornoxicam. Lornoxicam is a light sensitive and insoluble water soluble drug but unstable at higher temperature in water. So the effects of various co solvents in the solubility of  Lornoxicam have been evaluated. Lornoxicam was tried with co solvents such as PEG-400, β-cyclodextrin and Sodium Lauryl sulphate. The drug was made into injection formulation for administered as a SVP. Various batches of Lornoxicam injection formulation were prepared in order to assess the influence of heat, light, atmospheric oxygen and antioxidant on the stability of the drug and the formulations were also subjected to accelerated stability test. Out of all trials, formulation containing Sodium Lauryl sulphate was found to be more soluble, stable and passed all tests satisfactorily.

Over the years, inclusion complexation of drugs with β-cyclodextrin has emerged as a viable attempt to improve the dissolution of water insoluble drugs. The aim of the present work was to improve the dissolution rate of Glimepiride, by inclusion complexation with β-cyclodextrin. The stoichiometric ratio determined by phase solubility analysis for inclusion complexation of glimepiride with β-cyclodextrin was 1:1, 1:2, & 1:5. The solubility of glimepiride increased with increasing amount of β-cyclodextrin in water. Complexes of glimepiride were prepared with β-cyclodextrin by kneading method and physical mixture. The complexes were characterized by Fourier-transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) patterns. These studies indicated the inclusion of glimepiride in the cavity of β-cyclodextrin. The complexation resulted in a marked improvement in the solubility of glimepiride. An optimum increase in the dissolution rate of the drug was observed at a drug-polymer concentration of 1:5 concentrations. Mean dissolution time of glimepiride decreased significantly after preparation of complexes of glimepiride with β-cyclodextrin.

  Itraconazole, a poorly water soluble antimycotic agent, is promising agent for various diseases. To improve the solubility of itraconazole, the inclusion compound of Itraconazole with β-cyclodextrin was prepared by spray drying, solvent evaporation, kneading, lyophilization, physical mixture method and characterized by solubility, scanning electron microscopy, differential scanning calorimetry, FTIR and dissolution study. DSC and FTIR confirmed the formation of complex. The solubility of the prepared complex was found to be improved. Itraconazole complex by spray drying method and Itraconazole showed 95.65 % and 80.55% of drug release at the end of 48 h in dissolution study. It was concluded that the complex of itraconazole may be of potential use for improving the solubility of itraconazole and hence its bioavaibility.  

  Nimodipine is an antihypertensive, calcium channel blocker, vasodilator agent and used in the treatment of various cardiovascular disorders such as angina pectoris, cardiac arrhythmia and hypertension. Oral bioavailability of Nimodipine is around 13% and having half life 9 hrs. In present research work an attempt has been made to prepare fast dissolving tablets of Nimodipine by direct compression technique with β-cyclodextrin complexes using various superdisintegrants. The powder blends were subjected for pre-compressional parameters. The prepared tablets were evaluated for post-compressional parameters. The prepared tablets were characterized by DSC and FTIR Studies. No chemical interaction between drug and excipients was confirmed by DSC and IR studies. The values of pre-compression parameters evaluated were within prescribed limits and indicated good free flowing property. All the post-compressional parameter are evaluated were prescribed limits and results were within IP acceptable limits. The tablets were evaluated for the in-vitro disintegration time and it was observed that the time for all the formulations varied from 19.24 to 48.29 sec. The promising formulations CCP4, CCC4 and CSS1 shows the 90 % of drug released within 5-8 min. Among all the formulation CCP4 (15 % crospovidone) were found to be best and showed a disintegration time of 19.24 sec, 50 % of drug released in 0.96 min, and 90 %  of drug released in 4.78 min. The stability study was conducted as per the ICH guidelines and the formulations were found to be stable, with insignificant changes in hardness, drug content and disintegration time. These results revealed that fast dissolving tablets of the poorly soluble drug, Nimodipine, showing enhanced dissolution and, hence, better patient compliance. Key words: Fast dissolving tablets, Nimodipine, sodium starch glycolate, croscarmellose sodium, crospovidone,  β-cyclodextrin.