scholarly journals Bioavailability of Orally Delivered Alpha-Tocopherol by Poly(Lactic-Co-Glycolic) Acid (PLGA) Nanoparticles and Chitosan Covered PLGA Nanoparticles in F344 Rats

10.5772/63305 ◽  
2016 ◽  
Vol 3 ◽  
pp. 8 ◽  
Author(s):  
Lacey C. Simon ◽  
Rhett W. Stout ◽  
Cristina Sabliov

It is hypothesized that the bioavailability of αT (alpha-tocopherol), an antioxidant, can be improved when delivered by poly(lactic-co-glycolic) acid (PLGA) nanoparticles (NPs) and chitosan covered PLGA nanoparticles (PLGA-Chi NPs), and that the mucoadhesive properties of chitosan may enhance absorption of αT. PLGA and PLGA-Chi NPs were characterized by measuring entrapment efficiency, size, polydispersity, and zeta potential. Nanoparticle physical stability, chemical stability of entrapped αT, and release kinetics were also measured. Pharmacokinetic studies were conducted by administering PLGA (αT) NPs, PLGA-Chi (αT) NPs, and free αT via oral gavage in rats. The size and zeta potential of the two particle systems were 97.87 ± 2.63 nm and −36.2 ± 1.31 mV for PLGA(αT) NPs, and 134 ± 2.05 nm and 38.0 ± 2.90 mV for PLGA-Chi (αT) nanoparticles in DI water. The particle systems showed to be stable during various in vitro assays. Bioavailability of nanodelivered αT was improved compared to the free αT, by 170% and 121% for PLGA and PLGA-Chi NPs, respectively. It was concluded that while chitosan did not further improved bioavailability of αT, PLGA NPs protected the entrapped drug from the GI environment degradation and proved to be an effective delivery system for αT.

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1514
Author(s):  
Jéssica A. Magalhães ◽  
Denise C. Arruda ◽  
Maurício S. Baptista ◽  
Dayane B. Tada

The development of resistance against photodamage triggered by photodynamic therapy (PDT) is ascribed mainly to the cellular redox defenses and repair. If the tumor tissue is not promptly eliminated by the first few PDT sessions, PDT-resistance can be favored, challenging the efficacy of the treatment. Although the mechanism of PDT resistance is still unclear, in vitro assays have evidenced that it can be developed through the PARP damage-repair signaling pathway. Therefore, inhibition of poly(adenosine diphosphate (ADP)-ribose) polymerase (PARP) has the potential to increase PDT efficacy. This work reports on the synthesis of a controlled release system of a photosensitizer, methylene blue (MB) and a PARP-inhibitor, the veliparib. MB and veliparib were co-encapsulated in poly(lactic-co-glycolic acid) (PLGA) nanoparticles (VMB-NPs). A colloidal stable aqueous suspension of nanoparticles was obtained. The average hydrodynamic diameter was 90 nm and a narrow size distribution was obtained, with a polydispersity index (PDI) of 0.08. The release kinetics of MB and veliparib from VMB-NPs showed an initial burst of 8.7% and 58.3% release of the total amounts of MB and veliparib respectively, in the first 6 h, and a delayed release of up to 11.3% and 70%, in 19 days, for MB and veliparib, respectively. The VMB-NPs showed no cytotoxicity in the dark but the viability of B16F10-Nex2 cells decreased by 36% when the cells were irradiated (102 J/cm2, 660 nm) and treated with VMB-NPs containing 1.0 µM of MB and 8.3 µM of veliparib. Considering the increased photoactivity even at low MB and veliparib concentrations and the absence of cytotoxicity in dark, the co-encapsulation of MB and veliparib was shown to be a promising strategy to improve the PDT efficacy.


Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1632 ◽  
Author(s):  
A. Alper Öztürk ◽  
Evrim Yenilmez ◽  
Mustafa Güçlü Özarda

Clarithromycin (CLR) is a member of the macrolide antibiotic group. CLR has low systemic oral bioavailability and is a drug of class II of the Biopharmaceutical Classification System. In many studies, using nanoparticles (NPs) as a drug delivery system has been shown to increase the effectiveness and bioavailability of active drug substances. This study describes the development and evaluation of poly (lactic-co-glycolic acid) (PLGA) NPs and chitosan (CS)-coated PLGA NPs for oral delivery of CLR. NPs were obtained by nanoprecipitation technique and characterized in detail, and the effect of three molecular weights (Mw1: 7.000–17.000, Mw2: 38.000–54.000, Mw3: 50.000–190.000) of PLGA and CS coating on particle size (PS), zeta potential (ZP), entrapment efficiency (EE%), and release properties etc. were elucidated. Gastrointestinal stability and cryoprotectant effect tests were performed on the NPs. The PS of the prepared NPs were in the range of 178 to 578 nm and they were affected by the Mw and CS coating. In surface-modified formulations with CS, the ZP of the NPs increased significantly to positive values. EE% varied from 62% to 85%, depending upon the Mw and CS coating. In vitro release studies of CLR-loaded NPs showed an extended release up to 144 h. Peppas–Sahlin and Weibull kinetic model was found to fit best for CLR release from NPs. By the broth microdilution test method, the antibacterial activity of the formulations was determined on Staphylococcus aureus (ATCC 25923), Listeria monocytogenes (ATCC 1911), and Klebsiella pneumoniae (ATCC 700603). The structures of the formulations were clarified by thermal (DSC), FT-IR, and 1H-NMR analysis. The results showed that PS, ZP, EE%, and dissolution rates of NPs were directly related to the Mw of PLGA and CS coating.


Author(s):  
SRINIVAS MURTHY BR ◽  
PRASANNA RAJU YELAVARTHI ◽  
DEVANNA N

Objective: High lipophilicity and extensive hepatic metabolism limit oral application of orlistat in obesity treatment. Orlistat-loaded chitosan nanoparticles (CONPs) were optimized by 3-factor 3-level Box–Behnken design (BBD) and surfaced engineered to address limitations. Methods: CONPs were prepared by ionic gelation method. Amounts of chitosan (X1), sodium tripoly phosphate (X2), and orlistat (X3) were selected as independent factors, whereas % entrapment efficiency (Y1) and % drug release (Y2) were employed as responses in BBD. Three-dimensional response surface plots were run to understand the main interaction and quadratic effects of independent variables. Further optimized formulation was surface engineered by Eudragit L-100 (ECONPs) and characterized by FTIR, DSC, XRD, particle size, zeta potential, and SEM. Entrapment efficiency, release kinetics, stability, and in vitro cell line studies were carried out. Results: ECONPs were produced with an average size of 534.6 nm, zeta potential of +5.7 mV, EE of 78.62%, and DR of 80.86%. Eudragit coated CONPs anchored the release of orlistat at pH 6.8 desirable for duodenal targeting. Orlistat was released with low, burst, and sustained release manner over 24 h period followed first-order kinetics with Higuchi model with drug content of 84.87% and 78.44% of release. ECONPs possessed lipase inhibition with IC50 value of 8.0 μg/ml and viability against selected cell lines with CTC50 values (26.32–32.21 μg/ml). Conclusion: BBD was a promising tool in elucidating the insights of formulation variables of CONPs. ECONPs fulfilled the rationale of orlistat release, lipase inhibition, and viability against selected cell lines.


Author(s):  
AHMED GARDOUH ◽  
Samar H. Faheim ◽  
Samar M. Solyman

Objective: The main purpose of this work was to prepare tolnaftate (TOL) loaded nanostructured lipid carriers (NLCs), Evaluate its characteristics and in vitro release study. Methods: Tolnaftate loaded Nanostructured lipid carriers were prepared by the high shear homogenization method using different liquid lipids types (DERMAROL DCO® and DERMAROL CCT®) and concentrations, different concentration ratios of tween80® to span20® and different homogenization speeds. All the formulated nanoparticles were subjected to particle size (PS), zeta potential (ZP), polydispersity index (PI), drug entrapment efficiency (EE), Differential Scanning Calorimetry (DSC), Transmission Electron microscopy (TEM), release kinetics and in vitro release study was determined. Results: The results revealed that NLC dispersions had spherical shapes with an average size between 154.966±1.85 nm and 1078.4±103.02 nm. High entrapment efficiency was obtained with negatively charged zeta potential with PDI value ranging from 0.291±0.02 to 0.985±0.02. The release profiles of all formulations were characterized by a sustained release behavior over 24 h and the release rates increased as the amount of surfactant decreased. The release rate of TOL is expressed following the theoretical model by Higuchi. Conclusion: From this study, It can be concluded that NLCs are a good carrier for tolnaftate delivery


2014 ◽  
Vol 936 ◽  
pp. 717-722
Author(s):  
Yan Yan Li ◽  
Feng Song Liu

A solid oleoylchitosan (OCS) coated Poly (lactic-co-glycolic acid) (PLGA) nanoparticles (OCS-coated PLGA NPs) were prepared using the emulsification–evaporation method. The nanoparticles in suspension (TEM) and solid state (SEM) were spherical and very regular and compact. The effects of OCS concentration, PLGA concentration, drug concentration, and release media on drug entrapment efficiency and in vitro drug release behavior were investigated for the release properties using rifampicin (RFP) as a model drug. Both the increase of PLGA concentration and the increase of OCS concentration could decrease the drug release rates. The RFP release rates decreased as the RFP concentration increased. The RFP release rate was sensitive to the pH of the release media.


Coatings ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 439 ◽  
Author(s):  
Hibah M. Aldawsari ◽  
Nabil A. Alhakamy ◽  
Rayees Padder ◽  
Mohammad Husain ◽  
Shadab Md

Resveratrol (RES) is a polyphenolic compound which has shown beneficial pharmacological effects such as anti-inflammatory, antioxidant, and anti-cancer effects. However, poor aqueous solubility, bioavailability, and low stability are the major limitations to the clinical application of RES. Therefore, in the present study, chitosan (CS) coated PLGA nanoparticles of RES (CS-RES-PLGA NPs) was developed, characterized and its anticancer activity was evaluated in the H1299 lung carcinoma cell line. The effects of the increase in CS coating and cryoprotectant concentration on particle size, polydispersity index (PDI) and zeta potential (ZP) were determined. The particle size, PDI, ZP and entrapment efficiency of the optimized CS-RES-PLGA NPs were found to be 341.56 ± 7.90 nm, 0.117 ± 0.01, 26.88 ± 2.69 mV and 75.13% ± 1.02% respectively. The average particle size and ZP showed a steady increase with an increase in CS concentration. The increase in positive zeta potential is evident for higher CS concentrations. The effect of trehalose as cryoprotectant on average particle size was decreased significantly (p < 0.05) when it was increased from 1%−5% w/v. TEM and SEM showed uniform particle distribution with a smooth surface and spherical shape. The CS coating provides modulation of in vitro drug release and showed a sustained release pattern. The stability of RES loaded PLGA NPs was improved by CS coating. CS-coated NPs showed greater cytotoxicity and apoptotic activities compared to free RES. The CS coated NPs had a higher antioxidant effect than the free RES. Therefore, CS coated PLGA NPs could be a potential nanocarrier of RES to improve drug solubility, entrapment, sustain release, stability and therapeutic application.


2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Vijay D. Wagh ◽  
Dipak U. Apar

Dry eye disease is a common disease of the tear film caused by decreased tear production or increased evaporation. The objective of this study was to develop and evaluate poly (dl-lactide-co-glycolide) (PLGA) nanoparticles for CsA (CsA) ophthalmic delivery, for the treatment of dry eye disease. Topical CsA is currently the only and safe pharmacologic treatment of severe dry eye symptoms. Nanoparticles (NPs) were prepared by W/O solvent evaporation technique followed by probe sonicator and characterized for various properties such as particle size, entrapment efficiency, zeta potential,in vitrodrug release,in vitropermeation studies by Franz diffusion cells, XRD, DSC, SEM, and stability studies. The developed nanosuspension showed a mean particle size in the range from 128 to 253.50 nm before freeze drying and after freeze drying 145.60 to 260.0 nm. The drug entrapment efficiency was from 58.35 to 95.69% and production yield was found between52.29±2.4and85.30±2.1% in all preparations. The zeta potential of the Eudragit RL containing nanoparticles was positive, that is, 20.3 mV to 34.5 mV. The NPs formulations exhibited a biphasic drug release with initial burst followed by a very slow drug release and total cumulative release up to 24 h ranged from 69.83 to 91.92%. Kinetically, the release profiles of CsA from NPs appeared to fit best with the Higuchi model. The change of surface characteristics of NPs represents a useful approach for improvement of ocular retention and drug availability.


Author(s):  
Harjeet Singh ◽  
Ram Dayal Gupta ◽  
Girendra Gautam

Objective: The aim of this study was to formulate and optimize solid lipid nanoparticles (SLNs) for the enhancement of solubility and bioavailability of the poorly aqueous soluble drug rosuvastatin calcium.Methods: SLNs were prepared by slight modification of solvent emulsification-diffusion technique and analyzed for particle size, zeta potential, drug entrapment efficiency, in vitro drug release, stability, and pharmacokinetic studies. Rosuvastatin calcium SLNs were formulated using stearic acid as main lipid, poloxamer 407 as surfactant, and Tween 80 as cosurfactant.Results: All parameters were found to be in an acceptable range. Optimized formulation OR2 SLNs have shown mean particle size 115.49±2.97 nm with polydispersity index value of 0.456, zeta potential - 18.40 mV, 60.34% drug loading, and 97.16% drug entrapment efficiency. In vitro drug release was found to be 88.70±3.59% after 12 h with sustained release and was fitted with Higuchi model with a very high correlation coefficient (R2=0.9905). Transmission electron microscopy confirms that the SLNs of selected optimized formulation are circular in shape. Differential scanning calorimetry and X-ray diffraction confirm the formation of amorphous product. 1H nuclear magnetic resonance studies confirm the intermolecular hydrogen bonding between drug and lipid. Pharmacokinetic studies showed an optimized formulation OR2 SLNs enhanced bioavailability with 4.44-fold as compare to plain drug suspension. Optimized formulation OR2 SLNs have shown good stability at 25±2°C and 60±5°C relative humidity for 180 days.Conclusion: Thus, the current study can be useful for the successful development of optimized SLNs and able to enhance the bioavailability of poorly soluble drug rosuvastatin calcium.


Author(s):  
Anjali P.B ◽  
Jawahar N. ◽  
Jubie S. ◽  
Neetu Yadav ◽  
Selvaraj A. ◽  
...  

Background: : Epilepsy is a genuine neurological turmoil that effects around 50 million individuals around the world. Practically 30% of epileptic patients experience the ill effects of pharmaco-obstruction, which is related with social seclusion, subordinate conduct, low marriage rates, joblessness, mental issues and diminished personal satisfaction. At present accessible antiepileptic drugs have a restricted viability, and their negative properties limit their utilization and cause challenges in patient administration. Gabapentin 1-(aminomethyl)cyclohexane acetic acid, Gbp , (trade name Neurontin), a structural analog of γ-aminobutyric acid (GABA), BCS class 3 drug with having permeability issues. Objective: This work was an attempt to formulate and characterize a new approach to treat epilepsy by targeting to Phospholipase A2 Enzyme through Nanostructured Lipid Carrier. Methods: Docking studied carried out using Accelrys Discovery studio 4.1 Client and gabapentin and phosphotidylcholine were conjugated through chemical conjugation. Nanostructured lipid carrier (NLC) was prepared using hot homogenization technique. Results: The libdock score of Gabapentin- Phosphotidylcholine conjugate (192.535) were found to be more than Gabapentin (77.1084) and Phosphotidylcholine (150.212). For the optimized formulation the particle size (50.08), zeta potential (-1.48), PDI (0.472) and entrapment efficiency (77.8) was observed. The NLC was studies for in-vitro drug release studies and release kinetics. Finally found that the drug release from the NLC followed Higuchi release kinetic and the mode of drug release from the NLC was found to be Non- Fickian diffusion. Conclusion: The formulated Nanostructured lipid carrier of Gabapentin-Phosphotidylcholine conjugate may be able to use to prevent seizure.


Polymers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 923
Author(s):  
Shadab Md ◽  
Nabil A. Alhakamy ◽  
Hibah M. Aldawsari ◽  
Mohammad Husain ◽  
Nazia Khan ◽  
...  

Plumbagin (PLM) is a phytochemical which has shown cytotoxicity against of cancer cells both in vitro and in vivo. However, the clinical application of PLM has been hindered due to poor aqueous solubility and low bioavailability. The aim of the present study was to develop, optimize and evaluate PLM-loaded glycerosome (GM) gel and compare with conventional liposome (CL) for therapeutic efficacy against skin cancer. The GM formulations were optimized by employing design expert software by 3-level 3-factor design. The prepared GMs were characterized in vitro for vesicle size, size distribution, zeta potential, vesicle deformability, drug release, skin permeation, retention, texture, antioxidant and cytotoxicity activities. The optimized formulation showed a vesicle size of 119.20 ± 15.67 nm with a polydispersity index (PDI) of 0.145 ± 0.02, the zeta potential of −27 ± 5.12 mV and entrapment efficiency of 76.42 ± 9.98%. The optimized PLM-loaded GM formulation was transformed into a pre-formed gel which was prepared using Carbopol 934 polymer. The drug diffusion fluxes of CL gel and GM-loaded gel were 23.31 ±6.0 and 79.43 ± 12.43 µg/ cm2/h, respectively. The result of texture analysis revealed the adequate hardness, cohesiveness, consistency, and viscosity of the developed GM-loaded gel compared to CL gel. The confocal images showed that glycerosomal gel has deeper skin layer penetration as compared to the control solution. GM-loaded gel treated rat skin showed significantly (p < 0.05) higher drug accumulation in the dermis, higher cytotoxicity and higher antioxidant activity as compared to CL gel and PLM suspension. Thus, findings revealed that novel GM-loaded gel could be potential carriers for therapeutic intervention in skin cancer.


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