Aqueous multiphoton lithography with multifunctional silk-centred bio-resists.

Silk and silk fibroin, the biomaterial from nature, nowadays are being widely utilized in many cutting-edge micro/nanodevices/systems via advanced micro/nanofabrication techniques. Herein, for the first time to our knowledge, we report aqueous multiphoton lithography of diversiform-regenerated-silk-fibroin-centric inks using noncontact and maskless femtosecond laser direct writing (FsLDW). Initially, silk fibroin was FsLDW-crosslinked into arbitrary two/three-dimensional micro/nanostructures with good elastic properties merely using proper photosensitizers. More interestingly, silk/metal composite micro/nanodevices with multidimension-controllable metal content can be FsLDW-customized through laser-induced simultaneous fibroin oxidation/crosslinking and metal photoreduction using the simplest silk/Ag(+) or silk/[AuCl4](-) aqueous resists. Noticeably, during FsLDW, fibroin functions as biological reductant and matrix, while metal ions act as the oxidant. A FsLDW-fabricated prototyping silk/Ag microelectrode exhibited 10(4)-Ω(-1 ) m(-1)-scale adjustable electric conductivity. This work not only provides a powerful development to silk micro/nanoprocessing techniques but also creates a novel way to fabricate multifunctional metal/biomacromolecule complex micro/nanodevices for applications such as micro/nanoscale mechanical and electrical bioengineering and biosystems.

Protein-Based Three-Dimensional Whispering-Gallery-Mode Micro-Lasers with Stimulus-Responsiveness.

For the first time, proteins, a promising biocompatible and functionality-designable biomacromolecule material, acted as the host material to construct three-dimensional (3D) whispering-gallery-mode (WGM) microlasers by multiphoton femtosecond laser direct writing (FsLDW). Protein/Rhodamine B (RhB) composite biopolymer was used as optical gain medium innovatively. By adopting high-viscosity aqueous protein ink and optimized scanning mode, protein-based WGM microlasers were customized with exquisite true 3D geometry and smooth morphology. Comparable to previously reported artificial polymers, protein-based WGM microlasers here were endowed with valuable performances including steady operation in air and even in aqueous environments, and a higher quality value (Q) of several thousands (without annealing). Due to the "smart" feature of protein hydrogel, lasing spectrum was responsively adjusted by step of ~0.4 nm blueshift per 0.83-mmol/L Na2SO4 concentration change (0 ~ 5-mmol/L in total leading to ~2.59-nm blueshift). Importantly, other performances including Q, FWHM, FSR, peak intensities, exhibited good stability during adjustments. So, these protein-based 3D WGM microlasers might have potential in applications like optical biosensing and tunable "smart" biolasers, useful in novel photonic biosystems and bioengineering.

Customization of Protein Single Nanowires for Optical Biosensing.

An all-protein single-nanowire optical biosensor is constructed by a facile and general femtosecond laser direct writing approach with nanoscale structural customization. As-formed protein single nanowires show excellent optical properties (fine waveguiding performance and bio-applicable transmission windows), and are utilized as evanescent optical nanobiosensors for label-free biotin detection.

[Relationship between CD8+ T-cell CD28 expression and TCM differentiation type in patients with chronic aplastic anemia].

OBJECTIVE: To explore the relationship between CD8+ T-cell CD28 molecular expression in peripheral blood and TCM type in patients with chronic aplastic anemia (CAA). METHODS: Using flow cytometry to detect the CD28 expression in 45 in-patients or out-patients and 24 healthy subjects for control. And the relation with TCM type was analyzed from the immunological aspect. RESULTS: (1) The levels of CD8, CD28, CD8+ CD28+ expression and CD8+ CD28+/CD8+ CD28- were all higher in the CAA patients than those in the healthy subjects (P < 0.05 or P < 0.01). (2) The levels of CD28, CD8+ CD28+ expression and CD8+ CD28+/CD8+ CD28- were all higher in the CAA patients of Shen-Yin deficiency type than those in the CAA patients of Shen-Yang deficiency type (P < 0.05 or P < 0.01). CONCLUSION: (1) The abnormal high expression of peripheral blood co-stimulatory molecules CD28 suggested CD28 disorder may play an important role in immuno-pathogenesis of CAA. (2) The levels of peripheral CD28, CD8+ CD28+ expression and CD8+ CD28+/CD8+ CD28- can be taken as an objective indexes for TCM typing of CAA, which was disordered more severe in patients of Shen-Yin deficiency type than in those of Shen-Yang deficiency type.