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The dramatic increase of microbial resistances against conventional available antibiotics is a huge challenge to the effective treatment of infectious disease and thus becoming a daunting global threat of major concern, which necessitates the development of innovative therapeutics. Nanomaterial-based antimicrobial strategies have emerged as novel and promising tools to combat lethal bacteria and recalcitrant biofilm, featuring the abilities to evade existing drug resistance-related mechanisms. In this review, recent advances in “state-of-the-art” nanosystems which acting either as inherent therapeutics or nanocarriers for the precise delivery of antibiotics, are comprehensively summarized. Those nanosystems can effectively accumulate at the infectious sites, achieve multifunctional synergistic antibacterial efficacy, and provide controlled release of antibiotics in response to endogenous or exogenous stimulus (e.g., low pH, enzymes, or illumination). Especially, the nanoplatform that integrated with photothermal/photodynamic therapy (PTT/PDT) can enhance the bacterial destruction and biofilm penetration or ablation. In addition, nanoparticle-based approaches with enzymatically promoting bacterial killing, anti-virulence, and other mechanisms were also involved. Overall, this review provides crucial insights into the recent progress and remaining limitations of various antimicrobial nanotherapeutic strategies, and enlightens the further developments in this field simultaneously, which eventually benefiting public health.

Levodopa (L-DOPA), a precursor of dopamine, is commonly prescribed for the treatment of the Parkinson’s disease (PD). However, oral administration of levodopa results in a high level of homocysteine in the peripheral circulation, thereby elevating the risk of cardiovascular disease, and limiting its clinical application. Here, we report a non-invasive method to deliver levodopa to the brain by delivering L-DOPA-loaded sub-50 nm nanoparticles via brain-lymphatic vasculature. The hydrophilic L-DOPA was successfully encapsulated into nanoparticles of tannic acid (TA)/polyvinyl alcohol (PVA) via hydrogen bonding using the flash nanocomplexation (FNC) process, resulting in a high L-DOPA-loading capacity and uniform size in a scalable manner. Pharmacodynamics analysis in a PD rat model demonstrated that the levels of dopamine and tyrosine hydroxylase, which indicate the dopaminergic neuron functions, were increased by 2- and 4-fold, respectively. Movement disorders and cerebral oxidative stress of the rats were significantly improved. This formulation exhibited a high degree of biocompatibility as evidenced by lack of induced inflammation or other pathological changes in major organs. This antioxidative and drug-delivery platform administered through the brain-lymphatic vasculature shows promise for clinical treatment of the PD.

The performances of second harmonic generation (SHG) and optical parametric oscillator (OPO) in CdGeAs2 crystal are strongly influenced by surface quality. In this paper, the surfaces of samples were treated by mechanical polishing (MP), chemical polishing (CP), chemical–mechanical polishing (CMP) and CP following CMP closely (CMP + CP). Then, the surface state was characterized by optical microscopy (OM), scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). AFM measurements show that an ultra-smooth surface is achieved after CMP + CP treatment and the roughness value is 0.98 nm. Meanwhile, the roughness of the surfaces treated by MP, CP and CMP are 4.53, 2.83 and 1.38 nm, respectively. By XRD rocking curves, the diffraction peak which belongs to the wafer treated by CMP + CP is the highest in intensity and best symmetrical in shape. XPS analysis indicates that Ge4+ proportions of GeO2 in total Ge content of CdGeAs2 wafers’ surface after MP, CP, CMP and CMP + CP treatment are 27.6%, 42.8%, 6.1% and 30.3%, respectively.

A high-quality ZnGeP2 (ZGP) single crystal with large size of Φ30 mm × 80 mm was grown by a modified vertical Bridgman method. ZGP wafers were annealed with ZGP polycrystalline powder for 300 h at 550, 600 and 650 °C, respectively. The as-grown and annealed crystals were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR), IR microscope and energy-dispersive spectroscopy (EDS). Results show that the quality of all wafers is improved evidently after annealing and the optimum annealing temperature obtained is 600 °C. The IR transmittance of the wafer measured by FTIR is up to 56.78 % at wavelength of 2.0 μm nearby and exceeds 59.00 % in the wavelength range of 3.0–8.0 μm. The deviations from stoichiometry decrease, and the homogeneity of the crystal is also improved after annealing. In this paper, scanning infrared map was proposed as a new nondestructive method to evaluate optical quality and homogeneity of crystal through comparing the IR transmittance with the three-dimensional IR spectral contour map.

By the method of descending crucible with rotation, crack-free CdGeAs2 single crystals of Φ15 mm × 50 mm were grown in a furnace with three independent heating zones after optimizing the temperature field, and the descending and rotational speed to meet the need of CdGeAs2 crystal growth. The properties of as-grown crystal were characterized by a variety of techniques. The results of X-ray diffraction (XRD) show that there are two cleavage faces, which are (110) and (101). The peaks are in high intensity and good symmetry, which demonstrates that the crystal is integral in structure and well crystallized. The energy-dispersive spectrometry results indicate that the wafer of the CdGeAs2 crystal is closer to the stoichiometry. The IR transmittance of the wafer is ~48.6 % at 5.5 μm, and the maximum value is up to 51.6 % in the range of 2.3–18.0 μm. Etch pits of (001) face are observed and the density of the etch pits is evaluated to be 1 × 105 cm−2.