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Purpose: This study aims to investigate the effect of poly(D, L-lactic acid)10K (PDLLA10K) incorporation on the drug loading and stability of poly(ethylene glycol)2K-block-poly(D, L-lactide)2.4K (mPEG2k-b-PDLLA2.4k) micelles. In addition, a suitable lyophilization protector was screened for this micelle to obtain favorable lyophilized products. Methods: The incorporation ratios of PDLLA10k were screened based on the particle size and drug loading. The dynamic stability, core viscosity, drug release, stability in albumin, and in vivo pharmacokinetic characteristics of PDLLA10k incorporated micelles were compared with the original micelles. In addition, the particle size variation was used as an indicator to screen the most suitable lyophilization protectant for the micelles. DSC, FTIR, XRD were used to illustrate the mechanism of the lyophilized protectants. Results: After the incorporation of 5 wt% PDLLA10K, the maximum loading of mPEG2k-b-PDLLA2.4k micelles for TM-2 was increased from 26 wt% to 32 wt%, and the in vivo half-life was increased by 2.25-fold. Various stability of micelles was improved. Also, the micelles with hydroxypropyl-β-cyclodextrin (HP-β-CD) as lyophilization protectants had minimal variation in particle size. Conclusions: PDLLA10k incorporation can be employed as a strategy to increase the stability of mPEG2k-b-PDLLA2.4k micelles, which can be attributed to the viscosity building effect. HP-β-CD can be used as an effective lyophilization protectant since mPEG and HP-β-CD form the pseudopolyrotaxanesque inclusion complexes. [ABSTRACT FROM AUTHOR]

Myelosuppression is a prevalent and potentially life-threatening side effect during chemotherapy. As the main active component of ginseng, 20( S )-protopanaxadiol (PPD) is capable of relieving myelosuppression by restoring hematopoiesis and immunity. In this study, PPD was encapsulated in human albumin nanoparticles (PPD-HSA NPs) by nanoparticle albumin-bound (Nab) technology for intramuscular injection to optimize its pharmacokinetic properties and promote recovery of myelosuppression. The prepared PPD-HSA NPs had a particle size of about 280 nm with a narrow size distribution. PPD dispersed as an amorphous state within the PPD-HSA NPs, and the NPs exhibited in vitro sustained release behavior. PPD-HSA NPs showed a favorable pharmacokinetic profile with high absolute bioavailability, probably due to the fact that NPs entered into the blood circulation via lymphatic circulation and were eliminated slowly. In vivo distribution experiments demonstrated that PPD-HSA NPs were mainly distributed in the liver and spleen, but a strong fluorescence signal was also found in the inguinal lymph node, indicating drug absorption via a lymph route. The myelosuppressive model was established using cyclophosphamide as the inducer. Pharmacodynamic studies confirmed that PPD-HSA NPs were effective in promoting the level of white blood cells. Moreover, the neutrophil and lymphocyte counts were significantly higher in the PPD-HSA NPs group compared with the control group. This preliminary investigation revealed that PPD-HSA NPs via intramuscular administration may be an effective intervention strategy to alleviate myelosuppression.

g-C 3 N 4 -assisted interface engineering has been developed as an effective method to improve the efficiency and stability of perovskite solar cells (PSCs). However, most of the reported works used g-C 3 N 4 -induced single-interface modification, which is difficult to passivate the bilateral interfaces of the perovskite layer at the same time. In this paper, we fabricated two kinds of C 3 N 4 materials simultaneously (w-CN and y-CN) after the twice calcination of melamine and used them in the bilateral interface modification toward all-inorganic PSCs. The two kinds of C 3 N 4 play different roles in different interface engineering. On the front interface, w-CN could optimize band level arrangement and improve the perovskite film quality, which contributes to the efficiency of the device. On the back interface, y-CN could also improve the film quality of the perovskite layer, accelerating the extraction of charge carriers. The champion efficiency of the CsPbIBr 2 -based device treated by the bilateral interface is significantly enhanced from 7.8 to 10.1%. Moreover, the modified perovskite film exhibits negligible degradation after 40 min of exposure in the ambient environment with a relative humidity of 70%, while the pristine perovskite film has a rapid degradation within 20 min.