scholarly journals Improvement of Starch Digestion Usingα-Amylase Entrapped in Pectin-Polyvinyl Alcohol Blend

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Maurício Cruz ◽  
Kátia Fernandes ◽  
Cristine Cysneiros ◽  
Reginaldo Nassar ◽  
Samantha Caramori
Keyword(s):  
Polyvinyl Alcohol ◽  
Phosphate Buffer ◽  
Immobilized Enzyme ◽  
Biotechnological Applications ◽  
Solution Ph ◽  
Sodium Phosphate Buffer ◽  
Rate Of Dissolution ◽  
Water Ph ◽  
Repeated Use

Polyvinyl alcohol (PVA) and pectin blends were used to entrapα-amylase (Termamyl) using glutaraldehyde as a cross-linker. The effect of glutaraldehyde concentration (0.25, 0.5, 0.75, 1.0, and 1.25%) on the activity of the immobilized enzyme and rate of enzyme released was tested during a 24 h period. Characteristics of the material, such as scanning electron microscopy (SEM), tensile strength (TS), elongation, and rate of dissolution in water (pH 5.7), ruminal buffering solution (pH 7.0), and reactor containing 0.1 mol L−1sodium phosphate buffer (pH 6.5), were also analyzed. SEM results showed that the surfaces of the pectin/PVA/amylase films were highly irregular and rough. TS values increased as a function of glutaraldehyde concentration, whereas percentage of elongation (%E) decreased. Pectin/PVA/amylase films presented similar values of solubility in the tested solvents. The material obtained with 0.25% glutaraldehyde performed best with repeated use (active for 24 h), in a phosphate buffer reactor. By contrast, the material obtained with 1.25% glutaraldehyde presented higher performance duringin vitrotesting using an artificial rumen. The results suggest that pectin/PVA/amylase is a highly promising material for biotechnological applications.

Preparation and Characterization of Danazol Nanoparticles for Dissolution Improvement

2018 ◽  
Vol 9 (SPL1) ◽  
Author(s):  
Luma Safa el-din Al-Hassnaui
Keyword(s):  
Particle Size ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Amorphous State ◽  
Volume Ratio ◽  
In Vitro Dissolution ◽  
Buffer Solution ◽  
Solution Ph ◽  
Freeze Dried

Danazol is a synthetic steroid used for endometriosis treatment, haslow bioavailability as it is practically insoluble in water. This study has been carried out to prepare and characterize danazol nanoparticles by nanoprecipitation method at a different polymer to drug ratios of 0.5:1,1:1,2:1 and 3:1 using different polymers of CMC-30 and various grades of HPMC and PVP,as stabilizers. Variables that might affect the particle size as polymer type,polymer to drug ratio,temperature of precipitation,addition rate of danazol solution,volume ratio,time of stirring,concentrationof drug,have been investigated. The particle size of the prepared formulas has been in the nano-sized except those using CMC and the best formula has beenF20 at a polymer to drug ratio of0.5:1 which has given the smallest particle sizeof 33nm.The investigations of the drug–stabilizer compatibility havebeen studied by FTIR and DSC,crystalline state by XRD,size,and shape of nanoparticles by FESEM and the results showed that there has been no interaction between the danazol and stabilizer and there has been a partial conversion of danazol from crystalline to an amorphous state with a size below 100nm. Most of the studied factors havebeen found affect the particle size of the nanoparticles.The Entrapment efficiency has been (91.3% ± 0.4) in the (F20). The solubility study revealed that 6.75,4.97 and 5.1 folds increased of solubility of danazol for nanoparticles than that for raw in distilled water,0.1N HCl and in phosphate buffer of pH 6.8.The simple capsule has been prepared by incorporation of freeze-dried of F20 with lactose as a filler and the in vitro dissolution study has been conducted using 0.1N HCl (pH 1.2) with 2% w/v Brij-35,phosphate buffer solution(pH 6.8) with 2% w/v Brij-35as dissolution media. Within 30 minutes,100% of the danazol has been released from the nanoparticle capsule in both dissolution media compared to the raw and physical blend capsules as controls havebeen nearly complete in 120 minutes.One can conclude that Antisolvent method is an easy,efficient method to prepare danazol nanoparticles with an intense effect on solubility and faster in vitro dissolution rate than raw drug and its physical blend with stabilizer.

scholarly journals Mechanical properties and in vitro characterization of polyvinyl alcohol-nano-silver hydrogel wound dressings

2014 ◽  
Vol 4 (1) ◽  
pp. 20130049 ◽  
Author(s):  
R. N. Oliveira ◽  
R. Rouzé ◽  
B. Quilty ◽  
G. G. Alves ◽  
G. D. A. Soares ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Saline Solution ◽  
Antimicrobial Effect ◽  
Wound Dressings ◽  
Solution Ph ◽  
Swelling Properties ◽  
In Vitro Characterization ◽  
Gamma Irradiated ◽  
Potential Use

Polyvinyl alcohol (PVA) hydrogels are materials for potential use in burn healing. Silver nanoparticles can be synthesized within PVA hydrogels giving antimicrobial hydrogels. Hydrogels have to be swollen prior to their application, and the common medium available for that in hospitals is saline solution, but the hydrogel could also take up some of the wound's fluid. This work developed gamma-irradiated PVA/nano-Ag hydrogels for potential use in burn dressing applications. Silver nitrate (AgNO 3 ) was used as nano-Ag precursor agent. Saline solution, phosphate-buffered solution (PBS) pH 7.4 and solution pH 4.0 were used as swelling media. Microstructural evaluation revealed an effect of the nanoparticles on PVA crystallization. The swelling of the PVA-Ag samples in solution pH 4.0 was low, as was their silver delivery, compared with the equivalent samples swollen in the other media. The highest swelling and silver delivery were related to samples prepared with 0.50% AgNO 3 , and they also presented lower strength in PBS pH 7.4 and solution pH 4.0. Both PVA-Ag samples were also non-toxic and presented antimicrobial activity, confirming that 0.25% AgNO 3 concentration is sufficient to establish an antimicrobial effect. Both PVA-Ag samples presented suitable mechanical and swelling properties in all media, representative of potential burn site conditions.

scholarly journals The Effect of Alkali Metal, Magnesium, and Calcium Ions on the Motility of Fowl Spermatozoa

1958 ◽  
Vol 11 (4) ◽  
pp. 589 ◽  
Author(s):  
RG Wales ◽  
IG White
Keyword(s):  
Sodium Chloride ◽  
Alkali Metal ◽  
Calcium Ions ◽  
Phosphate Buffer ◽  
Sodium Phosphate ◽  
Cent Glucose ◽  
Sodium Phosphate Buffer ◽  
Cent Sodium

Potassium (5-45mM), magnesium (1�5-IS�5mM), and calcium (O�3-2�7mM) chlQrides each increase the viability of fowl spermatozoa in vitro when added to a diluent composed of O� 02M sodium phosphate buffer, 0�5 per cent. sodium chloride, and I� 5 per cent. glucose.

Formulation and Evaluation of Microbially- triggered tablets of Valdecoxib

2010 ◽  
Vol 2 (1) ◽  
Author(s):  
Surender Verma ◽  
S. Singh ◽  
D. Mishra ◽  
Atul Gupta ◽  
Rakesh Sharma
Keyword(s):  
Phosphate Buffer ◽  
Guar Gum ◽  
Oral Route ◽  
Matrix Tablets ◽  
In Vitro Dissolution ◽  
Wet Granulation ◽  
Dissolution Study ◽  
Caecal Content ◽  
Model Drug

The objective of present study was to develop colon targeted drug delivery using bacterially triggered approach through oral route. Valdecoxib (COX-2 inhibitor) was chosen as a model drug in order to target it to colon which may prove useful in inflammatory bowel disease and related disorders. Matrix tablets of Valdecoxib were prepared by wet granulation technique utilizing different ratio of Guar gum and Sodium starch glycholate. The prepared matrix tablets were evaluated for uniformity of weight, uniformity of content, hardness and in vitro dissolution study in simulated gastric and intestinal fluid (Phosphate Buffer pH-1.2, pH-6.8 and pH-7.4), followed by Dissolution study in bio-relevant dissolution media Phosphate Buffer (pH-6.8) containing rat caecal content. The results revealed that the formulated batch had released lesser quantity of drug at pH 1.2 and pH 7.4 in 2 hors whereas in biorelevent dissolution media containing rat caecal content it released significantly higher amount of drug which was also significantly higher than the dissolution media of same pH without caecal content (microflora) and it was concluded that guar gum can be used as a potential carrier for targeting drugs to colon.

Formulation and Evaluation of Nanosuspension of Simvastatin

2015 ◽  
Vol 8 (2) ◽  
pp. 2858-2873
Author(s):  
Rupali L. Shid ◽  
Shashikant N. Dhole ◽  
Nilesh Kulkarni ◽  
Santosh L Shid
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Factorial Design ◽  
Dissolution Rate ◽  
In Vitro Dissolution ◽  
Total Drug ◽  
23 Factorial Design ◽  
Rate Of Dissolution

Poor water solubility and slow dissolution rate are issues for the majority of upcoming and existing biologically active compounds. Simvastatin is poorly water-soluble drug and its bioavailability is very low from its crystalline form. The purpose of this study wasto increase the solubility and dissolution rate of simvastatin by the  preparation of nanosuspension by emulsification solvent diffusion method at laboratory scale. Prepared nanosus-pension was evaluated for its particle size and in vitro dissolution study and characterized by zeta potential,differential scanning calorimetry (DSC) and X-Ray diffractometry (XRD), motic digital microscopy, entrapment efficiency, total drug content, saturated solubility study and in vivo study. A 23 factorial design was employed to study the effect of independent variables, amount of SLS (X1), amount of PVPK-30 (X2) and poloxamer-188 (X3) and dependent variables are total drug content and polydispersity Index. The obtained results showed that particle size (nm) and rate of dissolution has been improved when nanosuspension prepared with the higherconcentration of PVPK-30 with the higher concentration of PVP K-30 and Poloxamer-188 and lower concentration of SLS. The particle size and zeta potential of optimized formulation was found to be 258.3 nm and 23.43. The rate of dissolution of the optimized nanosuspension was enhanced (90% in 60min), relative to plain simvastatin  (21% in 60 min), mainly due to the formation of nanosized particles. These results indicate the suitability of 23 factorial  design for preparation of simvastatin loaded nano-suspension significantly improved in vitro dissolution rate and thus possibly enhance fast onset of therapeutic drug effect. In vivo study shows increase in bioavailability in nanosuspension formulation than the plain simvastatin drug.

Enhanced oral bioavailability of Etodolac by liquisolid compact technique: optimisation, in-vitro and in-vivo evaluation

2020 ◽  
Vol 17 ◽  
Author(s):  
Bhumin K. Pathak ◽  
Meenakshi Raghav ◽  
Arti R. Thakkar ◽  
Bhavin A. Vyas ◽  
Pranav J. Shah
Keyword(s):  
Dissolution Rate ◽  
Amorphous State ◽  
Immediate Release ◽  
Angle Of Repose ◽  
Oral Suspension ◽  
Load Factor ◽  
In Vivo Evaluation ◽  
Rate Of Dissolution ◽  
Q 30

Background: Poor dissolution of Etodolac is one of the major challenges in achieving the desired therapeutic effect in oral therapy. Objective: This study aimed to assess the potential of liquisolid compact technique in increasing the rate of dissolution of Etodolac and thus its bioavailability. Methods: Liquisolid compacts were prepared using PEG 400, Avicel PH-200 and Aerosil 200 as non-volatile liquid, carrier and coating material respectively. Optimisation was carried out by applying a 32 full factorial design using Design expert software 11.0.3.0 to examine the effects of independent variables (load factor and carrier: coating ratio) on dependent variables (angle of repose and % cumulative drug release at 30 min [Q 30 min]).Assessment of bioavailability was based on pharmacokinetic study in rabbits and pharmacodynamics evaluation in rats respectively. Results: The formulation M3 was identified as the optimised formulation based on the better flow (lower angle of repose) and a higher rate of dissolution (Q 30 min >95%). The higher dissolution rate could be due to conversion of Etodolac into an amorphous molecularly dispersed state, availability of larger surface area, enhancement of aqueous solubility and enhanced wetting of drug particles. Studies with DSC, XRD, and SEM verified the transformation of Etodolac from crystalline to amorphous state, a key factor responsible for improving the dissolution rate. Pharmacokinetic profile of M3 was prominent, demonstrating higher absorption of Etodolac in comparison of oral suspension and immediate-release conventional tablets in rabbits. Liquisolid formulation exhibited 27% increment in paw thickness as compared to 57% and 46% increments for oral suspension and immediate-release conventional tablets respectively, after 7 hrs in carrageenan-induced paw model in rats. Conclusion: The results indicated liquisolid compact technique to be a promising strategy to enhance the bioavailability of Etodolac.

scholarly journals Development of Cephradine-Loaded Gelatin/Polyvinyl Alcohol Electrospun Nanofibers for Effective Diabetic Wound Healing: In-Vitro and In-Vivo Assessments

Pharmaceutics ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 349
Author(s):  
Anam Razzaq ◽  
Zaheer Ullah Khan ◽  
Aasim Saeed ◽  
Kiramat Ali Shah ◽  
Naveed Ullah Khan ◽  
...  
Keyword(s):  
Wound Healing ◽  
Polyvinyl Alcohol ◽  
Mtt Assay ◽  
Chronic Wound ◽  
Drug Loading ◽  
Group Identification ◽  
Wound Infections ◽  
Diabetic Wound

Diabetic wound infections caused by conventional antibiotic-resistant Staphylococcus aureus strains are fast emerging, leading to life-threatening situations (e.g., high costs, morbidity, and mortality) associated with delayed healing and chronic inflammation. Electrospinning is one of the most widely used techniques for the fabrication of nanofibers (NFs), induced by a high voltage applied to a drug-loaded polymer solution. Particular attention is given to electrospun NFs for pharmaceutical applications (e.g., original drug delivery systems) and tissue regeneration (e.g., as tissue scaffolds). However, there is a paucity of reports related to their application in diabetic wound infections. Therefore, we prepared eco-friendly, biodegradable, low-immunogenic, and biocompatible gelatin (GEL)/polyvinyl alcohol (PVA) electrospun NFs (BNFs), in which we loaded the broad-spectrum antibiotic cephradine (Ceph). The resulting drug-loaded NFs (LNFs) were characterized physically using ultraviolet-visible (UV-Vis) spectrophotometry (for drug loading capacity (LC), drug encapsulation efficiency (EE), and drug release kinetics determination), thermogravimetric analysis (TGA) (for thermostability evaluation), scanning electron microscopy (SEM) (for surface morphology analysis), and Fourier-transform infrared spectroscopy (FTIR) (for functional group identification). LNFs were further characterized biologically by in-vitro assessment of their potency against S. aureus clinical strains (N = 16) using the Kirby–Bauer test and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, by ex-vivo assessment to evaluate their cytotoxicity against primary human epidermal keratinocytes using MTT assay, and by in-vivo assessment to estimate their diabetic chronic wound-healing efficiency using NcZ10 diabetic/obese mice (N = 18). Thin and uniform NFs with a smooth surface and standard size (<400 nm) were observed by SEM at the optimized 5:5 (GEL:PVA) volumetric ratio. FTIR analyses confirmed the drug loading into BNFs. Compared to free Ceph, LNFs were significantly more thermostable and exhibited sustained/controlled Ceph release. LNFs also exerted a significantly stronger antibacterial activity both in-vitro and in-vivo. LNFs were significantly safer and more efficient for bacterial clearance-induced faster chronic wound healing. LNF-based therapy could be employed as a valuable dressing material to heal S. aureus-induced chronic wounds in diabetic subjects.

Decreased Platelet Vitamin C in Diabetes Mellitus; Possible Role in Peraggregatoon

1979 ◽  
Author(s):  
K.E. Sarji ◽  
J. Gonzalez ◽  
H. Hempling ◽  
J.A. Colwell
Keyword(s):  
Ascorbic Acid ◽  
Arachidonic Acid ◽  
Platelet Aggregation ◽  
Vitamin C ◽  
Platelet Rich Plasma ◽  
Solution Ph ◽  
Dose Dependent Fashion ◽  
Insulin Dependent Diabetic ◽  
Induced Aggregation

To determine whether Vitamin C might relate to the increased platelet sensitivity in the diabetic, we have measured levels of platelet Vitamin C and studied the effects of Vitamin C on platelet aggregation. Ascorbic acid levels in washed platelets from diabetics were significantly lower than from normals (4s.2±3 μg/1010 platelets vs. 2s.s±2 μg/1010 platelets, p<.001). The effects of ascorbic acid on platelet aggregation in vitro were studied by adding ascorbic acid in buffered solution (pH 7.35) prior to-aggregating agents. Ascorbic acid in platelet-rich plasma consistently inhibited platelet aggregation with threshold concentrations of ADP, epinephrine, and collagen. With washed platelets, ascorbic acid inhibited arachidonic, acid-induced aggregation. When platelets were incubated at 37°C for 10 minutes with varying concentrations of ascorbic acid, rewashed, and aggregation with arachidonic acid tested, aggregation was inhibited in a linear dose-dependent fashion. Oral ingestion of ascorbic acid (2 gm/day) for seven days by normal non-smoking males produced a marked inhibition of aggregation. In a similar study, platelets from an insulin-dependent diabetic showed no change in aggregation. These results suggest that platelet levels of ascorbic acid may relate to the hyperaggregat ion of platelets from diabetics.

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