ABSTRACT
Nowadays, nanotechnologies have shown wide application foreground in the biomedical field of medicine laboratory tests, drug delivery, gene therapy and bioremediation. However, in recent years, nanomaterials have been labeled poisonous, because of the disputes and misunderstandings of mainstream views on their safety. Besides, for the barriers of technical issues in preparation like: (1) low efficacy (poor PK & PD and low drug loading), (2) high cost (irreproducibility and difficulty in scale up), little of that research has been successfully translated into commercial products. Currently, along with the new theory of "physical damage is the origin of nanotoxicity", biodegradability and biocompatibility of nanomaterials are listed as the basic principle of safe application of nanomaterials. Combining scientific design based on molecular level with precision control of process engineering will provide a new strategy to overcome the core technical challenges. New turning point of translational medicine in nanotechnology may emerge.
ABSTRACT
Objective To ch aracterize and evaluate in vitro and in vivo of the 10-hydroxycamptothecin (HCPT) loaded human serum albumin nanoparticle (HSA-NP) prepared by drug-liquid compound method. Methods The HCPT-HSA-NP was prepared with low weight polyethylene glycol drug-liquid compound and blank albumin nanoparticle. Then the in vitro evaluations were conducted with tests of entrapment efficiency, solution stability, accumulative release, morphous investigation and X-ray powder diffraction. At the same time, the primary pharmacodynamics comparison between HCPT injection and the nano preparation (8 mg/kg) was carried out on animal tumor model. Results The obtained HCPT-HSA-NP fitted to the basal features of nano preparation. The entrapment efficiency was averagely higher than 99% for each sample and the solution was stable. In vitro accumulative release study showed that the preparation had long-term release pattern over 100 hours. In vivo pharmacodynamics study showed that the HCPT-HSA-NP was significantly more effective than HCPT injection (P<0.01). Conclusion The drug-liquid compound method can be used to prepare HCPT-HSA-NP.
ABSTRACT
Objective To establish an accelerated method that has good correlations with in vivo release data for formulation optimization and quality control purposes of thymopentin-loaded poly(DL-lactide-co-glycolide)(PLGA)microspheres. Methods In vivo thymopentin release from the microspheres was studied in Sprague-Dawley rats and relevant cumulative release curves were plotted. Key factors including release medium types,ethanol concentrations,surfactant concentrations and heating temperature were investigated for the in vitro accelerated release. The conditions for accelerated release were optimized to make the accelerated release cures fit the in vivo release well. The final optimized accelerated release method was validated in other two formulations. Results The final optimized accelerated release conditions were: 20% hydro-alcoholic solutions (V/V)and 0.06% Tween 80 (W/V)as the release media,gradient heating program (0-1 h at 40 °C,1-6 h at 45 °C and 6-30 h at 50 °C)as the media heating method. After fitted with the in vivo release curves,the correlation constant r2 of (8,13 and 28)×103 PLGA microspheres was 0.9783,0.9886 and 0.9780,respectively. Conclusion By introducing alcohol into the release media and applying gradient heating program,the reported accelerated method can be used in the formulation optimization and quality control of thymopentin-loaded PLGA microspheres.
ABSTRACT
Despite tre mendous research efforts have been devoted to the analysis of nanoparticles (NPs)biohazard,the potential mechanism for nanotoxicity has not yet been syste mati-cal y elucidated.This review intends to point out the confusions about nanotoxicity in the field and tries to look into the mecha-nism from a new perspective.Currently,there are three puzzles:① no relationship between dose and toxicity could be observed in nanotoxicity;②there is a theory for the″size effects″,however, it cannot explain some cases contrary to the doctrine;③ NPs made of different materials with various sizes could have the same toxic effects through sti mulating oxidative stress.In fact, human body is co mposed of various biological molecules,and the biological function of a living syste m is reflected by the inter-actions and conversions of those molecules.NPs,on the other hand,are the invader of human body which has no ability to transport or convert or digest the foreigner.Thus,NPs could cause celldamage due to the physical blockage of micro-circula-tion,celldestruction due to membrane rando m insertion,and celldysfunction due to physical contacting with big biological mole-cules.The physical damages caused by various NPs could be divided into three categories:adhesion lesion,card inlay and puncture.Above al ,by analyzing wide spectrum of NPs varying in co mposition,shape and size,the author draws a conclusion that physical damage is the origin of nanotoxicity.
ABSTRACT
Pharmaceutical preparations can directly affect the administration methods and therapeutic effects of drugs , which is a priority for the research and development of the military specialized medicament .Foreign armies started pharma-ceutical formulation research very early , and some of their research concepts and strategies are worth learning from .In this paper , dosage forms were used as the classification factor and several formulations with distinct military characteristics were described in detail .The features of military specialized medicament were analyzed from the perspective of pharmaceutics , based on which future development in the formulation of military specialized medicament was predicted .
ABSTRACT
100∶1. The specific growth rate of microcystis and P concentration in different P concentration and different N/P ratio cultures decreased with the culture time. Conclusions The initial P concentration affects the microcystis yield significantly, N/P ratio should be concerned in confirming the limiting factor. To control the P concentration in water through different methods will be the effective way to control water bloom.