Preparation and preliminary evaluation of SARS-CoV-2 DNA vaccine based on PLGA nanoparticles / 药学学报

We constructed and optimized the plasmid DNA (pDNA) Opt-S encoding the gene of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) protein, using poly (lactic-co-glycolic acid) copolymer (PLGA) as a delivery carrier for pDNA. PLGA-pDNA NPs were loaded by nanoprecipitation and its properties in vitro were preliminary evaluated. The results showed that the prepared PLGA-pDNA NPs were regular morphology, clear edges, with an average particle size of (184.2 ± 2.4) nm, polydisperse index (PDI) of 0.093 ± 0.013, zeta potential of (-68.10 ± 0.36) mV, and encapsulation rate of (98.92 ± 0.22)%. The PLGA-pDNA NPs were stable at -20 ℃ for 7 months and could protect pDNA against nuclease degradation. And they also exhibited sustained release of pDNA in vitro. The PLGA-pDNA NPs have low cytotoxicity and high safety. In addition, in vitro transfection experiments showed that the SARS-CoV-2 S gene could enter cells and be expressed. These results indicate that PLGA-pDNA NPs non-viral gene vector have simple preparation process and good performance, which are expected to provide a new idea for the research and development of SARS-CoV-2 vaccine.

Enhancing pharmaceutical potential and oral bioavailability of Allium cepa nanosuspension in male albino rats using response surface methodology

Objective: To enhance the pharmaceutical potential and oral bioavailability of quercetin contents of Allium cepa peel extract by novel nanosuspension technology. Methods: Nanoprecipitation approach was successfully used for the formulation of nanosuspension. To obtain pharmaceutical-grade nanosuspension with minimum particle size and polydispersity index, sodium lauryl sulphate was selected as a stabilizer. Important formulation parameters were statistically optimized by the response surface methodology approach. The optimized nanosuspension was subjected to stability and in vitro dissolution testing and characterized by scanning electron microscopy, atomic force microscopy, Fourier transform infrared spectroscopy, and zeta sizer. To evaluate the preeminence of nanosuspension over coarse suspension, comparative bioavailability studies were carried out in male albino rats. The pharmaceutical potential of developed nanosuspension was evaluated by antioxidant, antimicrobial, and toxicity studies. Results: The optimized nanosuspension showed an average particle size of 275.5 nm with a polydispersity index and zeta potential value of 0.415 and -48.8 mV, respectively. Atomic force microscopy revealed that the average particle size of nanosuspension was below 100 nm. The formulated nanosuspension showed better stability under refrigerated conditions. Nanosuspension showed an improved dissolution rate and a 2.14-fold greater plasma concentration of quercetin than coarse suspension. Moreover, the formulated nanosuspension exhibited enhanced antioxidant and antimicrobial potential and was non-toxic. Conclusions: Optimization of nanosuspension effectively improves the pharmaceutical potential and oral bioavailability of Allium cepa extract.

Graphene Conjugated Usnic Acid Nano-Formulation For The Treatment Of Topical Fungal Infection

Objective: The study aims to investigate the antifungal response of the dug usnic acid with the carrier graphene. Methods: Nano-precipitation method by sonication was adopted to formulate the conjugate. SEM test was performed to check the shape and average size of the conjugate. FTIR test was performed for the chemical interaction between the drug and the carrier. Ointment was prepared by the fusion method and the viscosity test was performed by Brookfield viscometer. Spreadability test was performed by slide method. Animal activity was performed to confirm the antifungal effect of the formulated nano-conjugate. Statistical analysis was done by Anova. Results: SEM study shows that the conjugate is in the nano range and possess a spherical shape. FTIR study shows no interaction between the drug and the carrier. The result of in vitro drug release study shows that the conjugate posses a higher drug release rate as compared to the drug alone. Topical drug administration is more suitable for the treatment of the fungal infection, so the nano-conjugate was incorporated into the ointment by geometric mixing. The viscosity and the spreadability test were performed on the different formulations of the ointment and the suitable one was selected for the topical administration. Anti-fungal study had been performed on the Wistar albino rats for 6 d. Skin culture of rats was performed for the formation of the fungal colonies. Statistical analysis by Anova gives p<0.001. It was found that the normal form of usnic acid, graphene and the nano form both possess anti-fungal activity as 3/6 and 2/6 experimental animals are cured by normal formulation and nano-formulation. Conclusion: The present anti-fungal study revealed that the nano-form of the conjugate possess higher anti-fungal activity than the normal formulation of usnic acid with graphene.

Emerging nanoparticulate systems: Preparation techniques and stimuli responsive release characteristics

Nanotechnology has become an outgrowing field in novel drug delivery system. It confers several merits overconventional formulations like increased solubility and bioavailability, targeted drug delivery and a decreaseddose of the drug. The selection of appropriate method for the preparation of nanoparticulate system depends on thephysicochemical characteristics of the drug to be loaded and polymer. This review has covered the most widelyacceptable preparation techniques for polymeric and lipidic nanoparticles including nanoprecipitation, milling,extrusion, supercritical fluid technology, salting out, gelation, sonication, high-pressure homogenization, and solventemulsification methods. Nanocarriers, the traditional nano-formulation drug delivery systems, encountered somemajor problems in process scale-up, reproducibility, and stability during storage. To circumvent these problems a newapproach has emerged which are “In situ or self-assembled nanoparticles drug delivery system.” Such approachescomprise experimentation with different types of polymers, surfactants or novel process in order to prepare a preconcentrate of drug formulation, which on entering into an aqueous medium (gastrointestinal fluid, blood) will formnanoparticles. The in situ nanoformulations can be the futuristic approach in nanocarriers to overcome the problemsassociated with the scale-up process and also minimize the cost of production. This review focuses on differentpreparation techniques for polymeric and lipidic nanocarriers preparation, in situ nanoformulation approaches andrelease characteristics of stimuli responsive nanoformulation

Nanoparticles with high payloads of pipemidic acid, a poorly soluble crystalline drug: drug-initiated polymerization and self-assembly approach

Nowadays, biodegradable polymers such as poly(lactic acid) (PLA), poly(D,L-lactic--glycolic acid) (PLGA) and poly(-caprolactone) (PCL) remain the most common biomaterials to produce drug-loaded nanoparticles (NPs). Pipemidic acid (PIP) is a poorly soluble antibiotic with a strong tendency to crystallize. PIP incorporation in PLA/PLGA NPs was challenging because of PIP crystals formation and burst release. As PIP had a poor affinity for the NPs, an alternative approach to encapsulation was used, consisting in coupling PIP to PCL. Thus, a PCL-PIP conjugate was successfully synthesized by an original drug-initiated polymerization in a single step without the need of catalyst. PCL-PIP was characterized by NMR, IR, SEC and mass spectrometry. PCL-PIP was used to prepare self-assembled NPs with PIP contents as high as 27% (/). The NPs were characterized by microscopy, DLS, NTA and TRPS. This study paves the way towards the production of NPs with high antibiotic payloads by drug-initiated polymerization. Further studies will deal with the synthesis of novel polymer-PIP conjugates with ester bonds between the drug and PCL. PIP can be considered as a model drug and the strategy developed here could be extended to other challenging antibiotics or anticancer drugs and employed to efficiently incorporate them in NPs.

Fabrication, Physicochemical Characterization and Evaluation of In vitro Anticancer Efficacy of a Novel pH Sensitive Polymeric Nanoparticles for Efficient Delivery of Hydrophobic Drug against Colon Cancer.

Objective: The present investigation was aimed to overcome the limitations and to enhance the incorporation of the hydrophobic drug into polymeric nanoparticles and characterize the prepared nanoparticles and also to evaluate the in vitro anticancer efficacy of prepared nanoparticles. Method: Nanoprecipitation method was used to prepare plain and hydrophobic drug (Camptothecin) loaded polymeric nanoparticles. Prepared nanoformulations were evaluated for average particle size, particle size uniformity, surface area, zeta potential, surface morphology, drug content, encapsulation efficiency, drug loading, in vitro release, anticancer activity and stability studies at long term and accelerated storage conditions. Results: Plain and Camptothecin loaded polymeric nanoparticles were successfully prepared by nanoprecipitation method using stirring technique. Prepared Camptothecin encapsulated polymeric nanoparticles were (a) spherical in shape with size < 100 nm, displayed excellent uniformity with <0.3 and zeta potential > 20 mV; (b) showed > 95% release in colonic environment; (c) demonstrated enhanced anticancer activity than pure Camptothecin; and (d) extremely stable at both long term and accelerated storage conditions. Conclusion: In summary, the investigation concluded that the prepared Camptothecin encapsulated polymeric nanoformulations may be considered as an attractive and promising formulation which significantly overcome the limitations of Camptothecin and synergistically enhance its anticancer activity.

Selection of an optimal method for the preparation of dual loaded flavono polymeric nanoparticle using analytical hierarchy process.

In this study, analytical hierarchy process was used to select an optimal method for the preparation of dual loaded flavono polymeric nanoparticles. Analytical hierarchy process involves structuring multiple choice criteria into a hierarchy, assessing the relative importance of criteria, comparing alternatives for each criterion and determining an overall ranking of the alternatives. Hierarchy model was developed with the goal in the first level, 10 criteria in the second level and methods for the preparation of polymeric nanoparticles in the third level. To assess the relative importance of criteria, all criteria were compared with each other using Saaty’s scale. To compare the methods, all the methods for the preparation of polymeric nanoparticles were compared with each other for each criterion using Saaty’s scale, which leads to the formation of pair-wise comparison matrixes and consistency ratio was calculated for the each pair-wise comparison matrix. The study result showed that the consistency ratio of each pair-wise comparison matrix were well within acceptable limits. Of 10 criteria, reproducible results received the maximum overall priority weight followed by desirable size. Of 10 methods, nanoprecipitation method received the maximum overall priority weight followed by supercritical fluid technology. Analytical hierarchy process has identified reproducible results as criteria preference and nanoprecipitation as an optimal method for the preparation of dual loaded flavono polymeric nanoparticles. The study concludes that the analytical hierarchy process has played a vital role in selecting an optimal method for the preparation of dual loaded flavono polymeric nanoparticles.

Selection of an optimal method for the preparation of dual loaded flavono polymeric nanoparticle using analytical hierarchy process.

In this study, analytical hierarchy process was used to select an optimal method for the preparation of dual loaded flavono polymeric nanoparticles. Analytical hierarchy process involves structuring multiple choice criteria into a hierarchy, assessing the relative importance of criteria, comparing alternatives for each criterion and determining an overall ranking of the alternatives. Hierarchy model was developed with the goal in the first level, 10 criteria in the second level and methods for the preparation of polymeric nanoparticles in the third level. To assess the relative importance of criteria, all criteria were compared with each other using Saaty’s scale. To compare the methods, all the methods for the preparation of polymeric nanoparticles were compared with each other for each criterion using Saaty’s scale, which leads to the formation of pair-wise comparison matrixes and consistency ratio was calculated for the each pair-wise comparison matrix. The study result showed that the consistency ratio of each pair-wise comparison matrix were well within acceptable limits. Of 10 criteria, reproducible results received the maximum overall priority weight followed by desirable size. Of 10 methods, nanoprecipitation method received the maximum overall priority weight followed by supercritical fluid technology. Analytical hierarchy process has identified reproducible results as criteria preference and nanoprecipitation as an optimal method for the preparation of dual loaded flavono polymeric nanoparticles. The study concludes that the analytical hierarchy process has played a vital role in selecting an optimal method for the preparation of dual loaded flavono polymeric nanoparticles.

Formulation and evaluation of Paclitaxel loaded PSA-PEG nanoparticles.

The main objective of this study was to prepare and evaluate PSA-PEG nanoparticles containing paclitaxel as a model drug by nanoprecipitation method. The influence of different experimental parameters on the particles size, entrapment efficiency, percent drug released etc was evaluated. SEM indicated that nanoparticles have discrete spherical structure without aggregation. The average particle size was found to be 123 -405 nm. The particle size of nanoparticles increases gradually with PSA-PEG polymer concentration. The drug content of nanoparticles also increases with increasing polymer concentration up to particular value. The in-vitro drug release behavior from all drug loaded batches was found to be zero order and provided sustained release over a period of 24 hours. Nanoparticles were stored at different temperatures and humidity as per ICH guidelines to check the stability.