Correction to “Biomimetic Solid Lipid Nanoparticles for Oral Bioavailability Enhancement of Low Molecular Weight Heparin and Its Lipid Conjugates: In Vitro and in Vivo Evaluation”

The objective of this study was to develop and evaluate lacidipine (LD) loaded solid lipid nanoparticles (LD-SLNs) for improving the oral bioavailability. LD-SLNs were prepared in two steps. First step was hot homogenization and next by ultrasonication method, using triglycerides (tripalmitin and tristearin), monoglyceride and surfactants (Poloxamer 188 and egg lecithin E80). The prepared LD-SLNs were characterized for particle size, PDI, zeta potential, drug content, entrapment efficiency (EE %). In vitro drug release studies using a dialysis bag method in 0.1N HCl and pH 6.8 phosphate buffer were conducted. In addition, long-term physical stability of the optimized SLNs was investigated at refrigerated and room temperature for 60 days. FTIR and DSC studies revealed that no interaction between the drug and lipids. LD-SLNs prepared with Dynasan-116 (F3), having the size of 141.86nm, PDI of 0.293, ZP of -22.3 m with 94.75% of EE was optimized and was stable for 60days. Scanning electron microscopic studies showed nearly spherical shaped particles. Further, pharmacokinetic studies were conducted in wistar rats. The relative bioavailability of LD in SLNs was 2.03 times when compared with that of the LD suspension. The results are indicative of SLNs as suitable lipid based carrier system for improving the oral bioavailability of LD.

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pH-responsive thiolated chitosan nanoparticles for oral low-molecular weight heparin delivery: in vitro and in vivo evaluation

Drug Delivery ◽

10.3109/10717544.2014.909908 ◽

2014 ◽

Vol 23 (1) ◽

pp. 238-247 ◽

Cited By ~ 27

Author(s):

Bo Fan ◽

Yang Xing ◽

Ying Zheng ◽

Chuan Sun ◽

Guixian Liang

Keyword(s):

Molecular Weight ◽

Low Molecular Weight Heparin ◽

Chitosan Nanoparticles ◽

Low Molecular Weight ◽

Ph Responsive ◽

In Vivo Evaluation ◽

Thiolated Chitosan

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Preparation, Characterization and in vivo Evaluation of Felodipine Solid-Lipid Nanoparticles for Improved Oral Bioavailability

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2015.8.4.1 ◽

2015 ◽

Vol 8 (4) ◽

pp. 2995-3002

Author(s):

Kishan V ◽

Usha Kiranmai Gondrala ◽

Narendar Dudhipala

Keyword(s):

Solid Lipid Nanoparticles ◽

Oral Bioavailability ◽

In Vitro Release ◽

Entrapment Efficiency ◽

Lipid Nanoparticles ◽

Scanning Calorimetry ◽

In Vivo Evaluation ◽

Solid Lipid

Felodipine is an antihypertensive drug with poor oral bioavailability due to the first pass metabolism. For improving the oral bioavailability, felodipine loaded solid lipid nanoparticles (SLNs) were developed using trimyristin, tripalmitin and glyceryl monostearate. Poloxamer 188 was used as surfactant. Lipid excipient compatibilities were confirmed by differential scanning calorimetry. SLN dispersions were prepared by hot homogenization of molten lipids and aqueous phase followed by ultrasonication at a temperature, above the melting point. SLNs were characterized for particle size, zeta potential, drug content, entrapment efficiency and crystallinity of lipid and drug. In vitro release studies were performed in 0.1N HCl and phosphate buffer of pH 6.8 using dialysis method. Pharmacokinetics of felodipine-SLNs after oral admini-stration in male Wistar rats was studied. The bioavailability of felodipine was increased by 1.75 fold when compared to that of a felodipine suspension.

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Effects of Unfractionated and Low Molecular Weight Heparins on Platelet Thromboxane Biosynthesis “In Vivo”

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648988 ◽

1994 ◽

Vol 72 (06) ◽

pp. 942-946 ◽

Cited By ~ 20

Author(s):

Raffaele Landolfi ◽

Erica De Candia ◽

Bianca Rocca ◽

Giovanni Ciabattoni ◽

Armando Antinori ◽

...

Keyword(s):

Molecular Weight ◽

Unfractionated Heparin ◽

Low Molecular Weight Heparin ◽

Primary Source ◽

In Vivo Studies ◽

Low Molecular Weight ◽

Heparin Administration ◽

To Receive

SummarySeveral “in vitro” and “in vivo” studies indicate that heparin administration may affect platelet function. In this study we investigated the effects of prophylactic heparin on thromboxane (Tx)A2 biosynthesis “in vivo”, as assessed by the urinary excretion of major enzymatic metabolites 11-dehydro-TxB2 and 2,3-dinor-TxB2. Twenty-four patients who were candidates for cholecystectomy because of uncomplicated lithiasis were randomly assigned to receive placebo, unfractionated heparin, low molecular weight heparin or unfractionaed heparin plus 100 mg aspirin. Measurements of daily excretion of Tx metabolites were performed before and during the treatment. In the groups assigned to placebo and to low molecular weight heparin there was no statistically significant modification of Tx metabolite excretion while patients receiving unfractionated heparin had a significant increase of both metabolites (11-dehydro-TxB2: 3844 ± 1388 vs 2092 ±777, p <0.05; 2,3-dinor-TxB2: 2737 ± 808 vs 1535 ± 771 pg/mg creatinine, p <0.05). In patients randomized to receive low-dose aspirin plus unfractionated heparin the excretion of the two metabolites was largely suppressed thus suggesting that platelets are the primary source of enhanced thromboxane biosynthesis associated with heparin administration. These data indicate that unfractionated heparin causes platelet activation “in vivo” and suggest that the use of low molecular weight heparin may avoid this complication.

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Neutralization of a Low Molecular Weight Heparin (LHN-1) and Conventional Heparin by Protamine Sulfate in Rats

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661675 ◽

1986 ◽

Vol 56 (03) ◽

pp. 318-322 ◽

Cited By ~ 18

Author(s):

V Diness ◽

P B Østergaard

Keyword(s):

Molecular Weight ◽

Low Molecular Weight Heparin ◽

Thrombus Formation ◽

Experimental Models ◽

Protamine Sulfate ◽

Low Molecular Weight ◽

Antithrombotic Effect ◽

Higher Doses

SummaryThe neutralization of a low molecular weight heparin (LHN-1) and conventional heparin (CH) by protamine sulfate has been studied in vitro and in vivo. In vitro, the APTT activity of CH was completely neutralized in parallel with the anti-Xa activity. The APTT activity of LHN-1 was almost completely neutralized in a way similar to the APTT activity of CH, whereas the anti-Xa activity of LHN-1 was only partially neutralized.In vivo, CH 3 mg/kg and LHN-1 7.2 mg/kg was given intravenously in rats. The APTT and anti-Xa activities, after neutralization by protamine sulfate in vivo, were similar to the results in vitro. In CH treated rats no haemorrhagic effect in the rat tail bleeding test and no antithrombotic effect in the rat stasis model was found at a protamine sulfate to heparin ratio of about 1, which neutralized APTT and anti-Xa activities. In LHN-1 treated rats the haemorrhagic effect was neutralized when APTT was close to normal whereas higher doses of protamine sulfate were required for neutralization of the antithrombotic effect. This probably reflects the fact that in most experimental models higher doses of heparin are needed to induce bleeding than to prevent thrombus formation. Our results demonstrate that even if complete neutralization of APTT and anti-Xa activities were not seen in LHN-1 treated rats, the in vivo effects of LHN-1 could be neutralized as efficiently as those of conventional heparin. The large fall in blood pressure caused by high doses of protamine sulfate alone was prevented by the prior injection of LHN-1.

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