Characteristics Of Chitosan Nanoparticles Research Articles

The influence of preparation factors on physical characteristics of chitosan nanoparticles

Chitosan has been shown to have great potentials in various pharmaceuticals and biomedical applications, including drug delivery. Derived from chitin abundantly available in the shells of crustaceans such as crabs and shrimps, this naturally occurring polysaccharide is classified based on its molecular weight: low, medium or high. This study aimed to explore the production of chitosan nanoparticles (NP) and the influence of different factors on the physical properties of the NP produced. These factors were the concentrations of acetic acid, chitosan flakes and tripolyphosphate (TPP). The design of experiment (DoE) approach was used to determine the optimum conditions for the production of chitosan NP, with particle size (nm) and polydispersity index (PdI) being set as the responses. The chitosan flakes were solubilised in acetic acid at a specific concentration determined by the DoE before dropwise addition of TPP in an ice bath. The mixture was stirred at room temperature and subsequently centrifuged to remove the unformed materials, and then was spray-dried into powder. The size, surface charge, shape and morphology of the particles produced were characterised and infrared analysis was conducted. The results showed that the particles were spherical, slightly positively charged (ζ-potential: +2.89 at pH 7) and the infrared analysis displayed important peaks of the chitosan NP. The DoE results showed that not all combinations of parameters could produce NP; hence, determination of concentration for each parameter is essential. The equation produced by the DoE will be a useful guide to minimise error in this circumstance. In conclusion, the acetic acid and chitosan flakes concentrations were found to influence the particle size positively, whilst the increment in TPP concentration will adversely affect the particle size. Similar pattern of response was also observed for the PdI of the particles. The methods used in this study has successfully produced spherical particles, with evidence of interactions between TPP and chitosan in the NP as shown in the infrared spectrum.

Characteristics, Cryoprotection Evaluation and In Vitro Release of BSA-Loaded Chitosan Nanoparticles.

Chitosan nanoparticles (CS-NPs) are under increasing investigation for the delivery of therapeutic proteins, such as vaccines, interferons, and biologics. A large number of studies have been taken on the characteristics of CS-NPs, and very few of these studies have focused on the microstructure of protein-loaded NPs. In this study, we prepared the CS-NPs by an ionic gelation method, and bovine serum albumin (BSA) was used as a model protein. Dynamic high pressure microfluidization (DHPM) was utilized to post-treat the nanoparticles so as to improve the uniformity, repeatability and controllability. The BSA-loaded NPs were then characterized for particle size, Zeta potential, morphology, encapsulation efficiency (EE), loading capacity (LC), and subsequent release kinetics. To improve the long-term stability of NPs, trehalose, glucose, sucrose, and mannitol were selected respectively to investigate the performance as a cryoprotectant. Furthermore, trehalose was used to obtain re-dispersible lyophilized NPs that can significantly reduce the dosage of cryoprotectants. Multiple spectroscopic techniques were used to characterize BSA-loaded NPs, in order to explain the release process of the NPs in vitro. The experimental results indicated that CS and Tripolyphosphate pentasodium (TPP) spontaneously formed the basic skeleton of the NPs through electrostatic interactions. BSA was incorporated in the basic skeleton, adsorbed on the surface of the NPs (some of which were inlaid on the NPs), without any change in structure and function. The release profiles of the NPs showed high consistency with the multispectral results.

Detection of Formation of Recombinant Human Keratinocyte Growth Factor Loaded Chitosan Nanoparticles Based on its Optical Properties

Background: Recombinant human keratinocyte growth factor (rHuKGF) is a protein used to treat oral mucositis caused by radio and chemotherapy in patients with hematologic malignancy. The rHuKGF is available in the form of intravenous bolus injection. In this study, new formulation of rHuKGF-loaded chitosan nanoparticles was developed to improve patient compliance. Methods: Chitosan nanoparticles (CNPs) loaded with rHuKGF were prepared by ionic gelation method. The tripolyphosphate (TPP) cross-linked with chitosan molecules at pH >5.0 and form the nanoparticles. An infrared spectroscopic technique was conducted to confirm the formation of nanoparticles as a result of ionotropic interaction between TPP and chitosan. Zeta Sizer was used to determine the size, polydispersity index (PdI) and zeta potential of the prepared nanoparticles. The morphological characteristics of CNPs were measured by field emission scanning electron microscope. During the formation of CNPs, the rHuKGF was entrapped in the nanoparticles. The loading capacity of rHuKGF in CNPs was observed to be dependent on how much amount of rHuKGF/TPP solution was added to convert all the chitosan molecules to form nanoparticles. A double beam UV/Vis spectroscopic method was used to detect the formation of these rHuKGF loaded CNPs based on their optical properties. Results: The produced rHuKGF-loaded CNPs were colorless, cloudy, and positively charged monodisperse with a spherical shape. The prepared CNPs have particles size of 119 ± 74.62 nm, surface charge of +20.3 ± 6.46 mV and 0.217 polydispersity index. The shape of prepared CNPs was found to be spherical using field emission scanning electron microscope (FESEM). The interfacial polyelectrolyte complexation between TPP and chitosan was confirmed by comparing the FTIR spectra of TPP, chitosan, physical mixture of chitosan and TPP and CNPs. The loading capacity of the rHuKGF in CNPs was found to be 93.3 ± 2.02%. The formation of rHuKGF loaded CNPs was detected by double beam UV/Vis Spectroscopy at 232.2 nm. Conclusion: The results of the current work were utilized for designing a continuous monitoring and detection system for the formation of CNPs. The outcomes of this technique are useful to avoid the loss of rHuKGF during nanoparticle formation and improving the loading capacity of CNPs.

Preparation of chitosan nanoparticles by TPP ionic gelation combined with spray drying, and the antibacterial activity of chitosan nanoparticles and a chitosan nanoparticle–amoxicillin complex

Chitosan nanoparticles were prepared from chitosan with various molecular weights by tripolyphosphate (TPP) ionic gelation combined with a spray drying method. The morphologies and characteristics of chitosan nanoparticles were determined by TEM, FE-SEM and from their mean sizes and zeta potentials. The effect of chitosan molecular weight (130, 276, 760 and 1200 cPs) and size of spray dryer nozzle (4.0, 5.5 and 7.0 µm) on mean size, size distribution and zeta potential values of chitosan nanoparticles was investigated. The results showed that the mean size of chitosan nanoparticles was in the range of 166–1230 nm and the zeta potential value ranged from 34.9 to 59 mV, depending on the molecular weight of chitosan and size of the spray dryer nozzles. The lower the molecular weight of chitosan, the smaller the size of the chitosan nanoparticles and the higher the zeta potential. A test for the antibacterial activity of chitosan nanoparticles (only) and a chitosan nanoparticle–amoxicillin complex against Streptococcus pneumoniae was also conducted. The results indicated that a smaller chitosan nanoparticle and higher zeta potential showed higher antibacterial activity. The chitosan nanoparticle–amoxicillin complex resulted in improved antibacterial activity as compared to amoxicillin and chitosan nanopaticles alone. Using a chitosan nanoparticle–amoxicillin complex could reduce by three times the dosage of amoxicillin while still completely inhibiting S. pneumoniae.

Development of oral DNA vaccine based on chitosan nanoparticles for the immunization against reddish body iridovirus in turbots (Scophthalmus maximus)

Turbot reddish body iridovirus (TRBIV), a piscine iridovirus, causes viral reddish body syndrome (VRBS) in turbot and is highly lethal to the fish. Infection of the virus hampers the development of turbot aquaculture. Hence, it is important to develop a preventive vaccine. In our previous study, we constructed and evaluated the immunization efficacy of the recombinant plasmid, pEGFP-N2-TRBIV-MCP. In the present study, an oral nanoparticle-based DNA vaccine against TRBIV was developed to evaluate the immunization effectiveness in turbots (Scophthalmus maximus) through oral administration. We prepared chitosan nanoparticles enwrapping plasmid DNA using ionic gelation process, and the characteristics of chitosan nanoparticles were analyzed by transmission electron microscope and Malvin ZS analyzer. The results revealed that the chitosan nanoparticle plasmids encoding DNA (pDNA-CS-NPs) were spherical shape with the particle size and zeta potential of 145.5±1.5nm and 24.3±0.5, respectively. The loading rate and encapsulation efficiency were 92.8±1.38% and 63.7±0.89%, respectively. In vitro transfection, pDNA-CS-NPs was transferred into eukaryotic cells, turbot cell TK line, and transient expression of pDNA-CS-NPs was detected by RT-PCR and laser scanning confocal microscope. After oral administration, the expression of the antigen gene could be detected in different tissues of turbots (S. maximus) at 20 and 40days post-vaccination. The pDNA-CS-NPs clearly induced an innate and specific immune response, and significantly up-regulated the expression of MHCIα, IIα, IFN-1, IFN-g, Mx-1, IL8 and Mx. In addition, strong protection with relative survival rate of 68% was recorded in the orally-vaccinated turbots, which could produce the detectable level of anti-TRBIV antibody during 90days. These data in this study suggested that pDNA-CS-NPs were promising carriers for plasmid DNA vaccine through oral vaccination. This method could be extended to the development of other oral vaccines and applied in other fish species against TRBIV. Statement of relevanceIn this work, an oral nanoparticle-based DNA vaccine against TRBIV was developed to evaluate the immunization effectiveness in turbots (S. maximus) through oral administration. We prepared chitosan nanoparticles enwrapping plasmid DNA using ionic gelation process, and the characteristics of chitosan nanoparticles were analyzed by transmission electron microscope and Malvin ZS analyzer. I hope this paper is suitable for aquaculture.

Adsorption Kinetics of Pb<sup>2+</sup> Ions Using Chitosan Nanoparticles

Chitosan nanoparticles were prepared by crosslinkingusing TPP. SEM showed that chitosan nanoparticles were successfully obtained.The adsorption characteristics of chitosan nanoparticles were evaluated. Theresults demonstrated that chitosan nanoparticles were suitable for adsorbent toremoval Pb2+. The parameters for the adsorption of Pb2+by chitosan nanoparticles were also determined. It was shown that chitosannanoparticles were fit for Langmuir’s isotherm model and that the adsorptionkinetics of Pb2+ described by the pseudo-second-order model could bebest.