Exenatide loaded PLGA microspheres for long-acting antidiabetic therapy: preparation, characterization, pharmacokinetics and pharmacodynamics

We herein fabricated the exenatide-loaded microspheres by a water in oil in oil (W/O/O) method, which presented great effect on glycemic control with low initial burst release and reduced risk of gastrointestinal intolerance and hypoglycemia.

Download Full-text

Effect of Self-healing Encapsulation on the Initial Burst Release from PLGA Microspheres Containing a Long-Acting Prostacyclin Agonist, ONO-1301

Chemical and Pharmaceutical Bulletin ◽

10.1248/cpb.c17-00025 ◽

2017 ◽

Vol 65 (7) ◽

pp. 653-659 ◽

Cited By ~ 6

Author(s):

Mai Hazekawa ◽

Honami Kojima ◽

Tamami Haraguchi ◽

Miyako Yoshida ◽

Takahiro Uchida

Keyword(s):

Burst Release ◽

Self Healing ◽

Plga Microspheres ◽

Initial Burst ◽

Initial Burst Release ◽

Long Acting

Download Full-text

In vitro drug release and antibacterial activity evaluation of silk fibroin coated vancomycin hydrochloride loaded poly (lactic-co-glycolic acid) (PLGA) sustained release microspheres

Journal of Biomaterials Applications ◽

10.1177/08853282211064098 ◽

2022 ◽

pp. 088532822110640

Author(s):

Shengtang Li ◽

Xuewen Shi ◽

Bo Xu ◽

Jian Wang ◽

Peng Li ◽

...

Keyword(s):

Drug Release ◽

Encapsulation Efficiency ◽

Glycolic Acid ◽

Drug Loading ◽

Burst Release ◽

Plga Microspheres ◽

In Vitro Drug Release ◽

Initial Burst ◽

Initial Burst Release

Currently, the treatment of osteomyelitis poses a great challenge to clinical orthopedics. The use of biodegradable materials combined with antibiotics provides a completely new option for the treatment of osteomyelitis. In this study, vancomycin hydrochloride (VANCO) loaded poly (lactic-co-glycolic acid) (PLGA) microspheres were prepared by a double emulsion solvent evaporation method, and the in vitro drug release behaviors of the drug loaded microspheres were explored after coating with different concentrations of silk fibroin (SF). Drug loading, encapsulation efficiency, Scanning electron microscopy, particle size analysis, Fourier transform infrared spectroscopy, hydrophilicity, in vitro drug release, and in vitro antibacterial activity were evaluated. The results showed that the drug loading of vancomycin loaded PLGA microspheres was (24.11 ±1.72)%, and the encapsulation efficiency was (48.21 ±3.44)%. The in vitro drug release indicated that the drug loaded microspheres showed an obvious initial burst release, and the drug loaded microspheres coated with SF could alleviate the initial burst release in varying degrees. It also can reduce the amount of cumulative drug release, and the effect of microspheres coated with 0.1% concentration of SF is the best. The time of in vitro drug release in different groups of drug loaded microspheres can be up to 28 days. The microspheres coated with (0.1%SF) or without (0%SF) SF showed a cumulative release of (82.50±3.51)% and (67.70±3.81)%,respectively. Therefore, the surface coating with SF of vancomycin loaded microspheres can alleviate the initial burst release, reduce the cumulative drug release, potentially prolong the drug action time, and improve the anti-infection effect.

Download Full-text

PLGA Microspheres with Alginate-Coated Large Pores for the Formulation of an Injectable Depot of Donepezil Hydrochloride

Pharmaceutics ◽

10.3390/pharmaceutics12040311 ◽

2020 ◽

Vol 12 (4) ◽

pp. 311

Author(s):

Dohyun Kim ◽

Tae Hee Han ◽

Seong-Chul Hong ◽

Sun Jae Park ◽

Yong Hak Lee ◽

...

Keyword(s):

Sustained Release ◽

Patient Compliance ◽

Calcium Alginate ◽

Burst Release ◽

Plga Microspheres ◽

Large Space ◽

Initial Burst ◽

Initial Burst Release ◽

Donepezil Hydrochloride ◽

Alginate Coating

As the main symptom of Alzheimer’s disease-related dementia is memory loss, patient compliance for donepezil hydrochloride (donepezil), administered as once-daily oral formulations, is poor. Thus, we aimed to design poly(lactic-co-glycolic acid) (PLGA) microspheres (MS) with alginate-coated large pores as an injectable depot of donepezil exhibiting sustained release over 2–3 weeks. The PLGA MS with large pores could provide large space for loading drugs with high loading capacity, and thereby sufficient amounts of drugs were considered to be delivered with minimal use of PLGA MS being injected. However, initial burst release of donepezil from the porous PLGA MS was observed. To reduce this initial burst release, the surface pores were closed with calcium alginate coating using a spray-ionotropic gelation method. The final pore-closed PLGA MS showed in vitro sustained release for approximately 3 weeks, and the initial burst release was remarkably decreased by the calcium alginate coating. In the prediction of plasma drug concentration profiles using convolution method, the mean residence time of the pore-closed PLGA MS was 2.7-fold longer than that of the porous PLGA MS. Therefore, our results reveal that our pore-closed PLGA MS formulation is a promising candidate for the treatment of dementia with high patient compliance.

Download Full-text

Development of 5-iodo-2′-deoxyuridine milling process to reduce initial burst release from PLGA microparticles

International Journal of Pharmaceutics ◽

10.1016/s0378-5173(98)00380-9 ◽

1999 ◽

Vol 178 (2) ◽

pp. 257-268 ◽

Cited By ~ 24

Author(s):

A Gèze

Keyword(s):

Milling Process ◽

Burst Release ◽

Initial Burst ◽

Initial Burst Release ◽

Plga Microparticles

Download Full-text

Drug Delivery Applications of Core-Sheath Nanofibers Prepared by Coaxial Electrospinning: A Review

Pharmaceutics ◽

10.3390/pharmaceutics11070305 ◽

2019 ◽

Vol 11 (7) ◽

pp. 305 ◽

Cited By ~ 49

Author(s):

Bishweshwar Pant ◽

Mira Park ◽

Soo-Jin Park

Keyword(s):

Drug Delivery ◽

Electrospun Nanofibers ◽

Coaxial Electrospinning ◽

Burst Release ◽

High Porosity ◽

Nanofiber Membrane ◽

Initial Burst ◽

Initial Burst Release ◽

Small Pore ◽

Drug Delivery Applications

Electrospinning has emerged as one of the potential techniques for producing nanofibers. The use of electrospun nanofibers in drug delivery has increased rapidly over recent years due to their valuable properties, which include a large surface area, high porosity, small pore size, superior mechanical properties, and ease of surface modification. A drug loaded nanofiber membrane can be prepared via electrospinning using a model drug and polymer solution; however, the release of the drug from the nanofiber membrane in a safe and controlled way is challenging as a result of the initial burst release. Employing a core-sheath design provides a promising solution for controlling the initial burst release. Numerous studies have reported on the preparation of core-sheath nanofibers by coaxial electrospinning for drug delivery applications. This paper summarizes the physical phenomena, the effects of various parameters in coaxial electrospinning, and the usefulness of core-sheath nanofibers in drug delivery. Furthermore, this report also highlights the future challenges involved in utilizing core-sheath nanofibers for drug delivery applications.

Download Full-text

PLGA Microspheres of hGH of Preserved Native State Prepared Using a Self-Regulated Process

Pharmaceutics ◽

10.3390/pharmaceutics12070683 ◽

2020 ◽

Vol 12 (7) ◽

pp. 683

Author(s):

Jebun Nessa Diana ◽

Ying Tao ◽

Qiran Du ◽

Meng Wang ◽

Chinta Uday Kumar ◽

...

Keyword(s):

Osmotic Pressure ◽

Recombinant Human Growth Hormone ◽

Human Growth ◽

High Dose ◽

Burst Release ◽

Polymeric Microspheres ◽

Aqueous Emulsion ◽

Initial Burst ◽

Initial Burst Release ◽

Physical Chemical

The challenges of formulating recombinant human growth hormone (rhGH) into sustained-release polymeric microspheres include two mutual causal factors, protein denaturing by the formulation process and severe initial burst release related with relative high dose. The stabilizers to protect the proteins must not evoke osmotic pressure inside the microspheres, and the contact of the protein with the interface between water and organic solution of the polymer must be minimized. To meet these criteria, rhGH was pre-formulated into polysaccharide particles via an aqueous–aqueous emulsion in the present study, followed by encapsulating the particles into microspheres through a self-regulated process to minimize the contact of the protein with the water–oil interface. Polysaccharides as the protein stabilizer did not evoke osmotic pressure as small sugar stabilizers, the cause of severe initial burst release. Reduced initial burst enabled reduced protein loading to 9% (from 22% of the once commercialized Nutropin depot), which in turn reduced the dosage form index from 80 to 8.7 and eased the initial burst. A series of physical chemical characterizations as well as biologic and pharmacokinetic assays confirmed that the present method is practically feasible for preparing microspheres of proteins.

Download Full-text

Effects of the process parameters on the initial burst release of poly(lactide-co-glycolide) microspheres containing bovine serum albumin by the double-emulsion solvent evaporation/extraction method

Journal of Applied Polymer Science ◽

10.1002/app.30282 ◽

2010 ◽

Vol 115 (5) ◽

pp. 2599-2608 ◽

Cited By ~ 13

Author(s):

Zheng Wang

Keyword(s):

Bovine Serum Albumin ◽

Serum Albumin ◽

Process Parameters ◽

Bovine Serum ◽

Extraction Method ◽

Double Emulsion ◽

Solvent Evaporation ◽

Burst Release ◽

Initial Burst ◽

Initial Burst Release

Download Full-text

Novel Electrospun Bicomponent Scaffolds for Bone Tissue Engineering: Fabrication, Characterization and Sustained Release of Growth Factor

MRS Proceedings ◽

10.1557/opl.2012.395 ◽

2012 ◽

Vol 1418 ◽

Author(s):

Chong Wang ◽

Min Wang ◽

Xiao-Yan Yuan

Keyword(s):

Tissue Engineering ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Biological Tissues ◽

Osteoblastic Cell ◽

Burst Release ◽

Electrospinning Technique ◽

Initial Burst ◽

Initial Burst Release

ABSTRACTElectrospinning is a versatile technique for fabricating three-dimensional (3D) nanofibrous scaffolds and the scaffolds have been found to elicit desirable cellular behavior for tissue regeneration because the nanofibrous structures mimic the nanofibrous extracellular matrix (ECM) of biological tissues. From the material point of view, the ECM of bone is a nanofibrous nanocomposite consisting of an organic matrix (mainly collagen) and inorganic bone apatite nanoparticles. Therefore, for bone tissue engineering scaffolds, it is natural to construct nanofibrous nanocomposites having a biodegradable polymer matrix and nanosized bioactive bioceramics. Our previous studies demonstrated: (1) electrospun nanocomposite fiber loaded with calcium phosphate (Ca-P) were osteoconductive and could promote osteoblastic cell proliferation and differentiation better than pure polymer fibers; (2) The controlled release of recombinant human bone morphogenetic protein (rhBMP-2) from scaffolds provided the scaffolds with desired osteoinductivity. In the current investigation, novel bicomponent scaffolds for bone tissue engineering were produced using our established dual-source dual-power electrospinning technique to achieve both osteoconductivity and osteoinductivity. In the bicomponent scaffolds, one fibrous component was electrospun Ca-P/PLGA nanocomposite fibers and the other component was emulsion electrospun PDLLA nanofibers incorporated with rhBMP-2. Through electrospinning optimization, both fibers were evenly distributed in bicomponent scaffolds. The mass ratio of rhBMP-2/PDLLA fibers to Ca-P/PLGA fibers in bicomponent scaffolds could be controlled using multiple syringes. The structure and morphology of mono- and bicomponent scaffolds were examined. The in vitro release of rhBMP-2 from mono- and bicomponent scaffolds showed different release amount but similar release profile, exhibiting an initial burst release. Blending PDLLA with polyethylene glycol (PEG) could reduce the initial burst release of rhBMP-2.

Download Full-text