Site-specific delivery of a natural chemotherapeutic agent to human lung cancer cells using biotinylated 2D rGO nanocarriers
MATERIALS SCIENCE & ENGINEERING C-MATERIALS FOR BIOLOGICAL APPLICATIONS
Authors: Gupta, Nitin; Bhagat, Stuti; Singh, Mandeep; Jangid, Ashok Kumar; Bansal, Vipul; Singh, Sanjay; Pooja, Deep; Kulhari, Hitesh
Abstract
Chemotherapy has remained one of the most commonly employed treatment modalities for cancer. Despite the clinical availability of a large number of chemotherapeutic agents, the uncontrolled systemic distribution and the associated harmful side effects of chemotherapeutic agents pose major challenges demanding concerted efforts to enhance their cancer targetability. The layered structure of two-dimensional (2D) materials offers new opportunities by increasing the drug pay-load influencing the drug-release kinetics in a cancer micro-environment and facilitating targetability through the large accessible surface area. To investigate such potential benefits of 2D materials, we have developed a biocompatible targeted 2D drug delivery system using graphene oxide (GO) as a model nanocarrier (NC) that could hold a high concentration of gallic acid (GA), a natural chemotherapeutic agent found in green tea. Interestingly, the antioxidant nature of GA also reduced GO to a high-quality few-layered thin reduced-graphene oxide (rGO) during drug loading while forming rGO nanocarrier (rGONC). The biotinylated rGONC further improved their targetability to A549 human lung carcinoma cells and they enhanced cellular internalization efficiency. From these targeted 2D NCs, the drug could release only slowly at the physiological pH but liberated rapidly at lower pH encountered by the tumor microenvironment resulting in significant toxicity toward the lung carcinoma cells. As such, this work opens up new possibilities for employing 2D materials for targeted chemotherapeutic applications.
A ligation-triggered and protein-assisted fluorescence anisotropy amplification platform for sensitive and selective detection of small molecules in a biological matrix
RSC ADVANCES
Authors: Chen, Meizi; Wan, Bing; Du, Wei; Hu, Hongbo; Zeng, Long; Duan, Xintong; Liu, Jia; Wei, Zixiang; Tang, Li; Peng, Yongbo
Abstract
Effective detection of biomolecules is important for biological research and medical diagnosis. We here propose a ligation-triggered and protein-assisted fluorescence anisotropy amplification platform for sensitive and selective detection of small biomolecules in a complex biological matrix. In the proposed method, in the presence of target small molecules, FAM-labeled DNA 1 and biotin-labeled DNA2 were ligated to produce an integrated DNA. As a result, taking advantage of the extraordinary strong interaction between biotin and streptavidin, we employed a novel mass amplification strategy for sensitive detection of small molecules through fluorescence anisotropy. The method could detect ATP from 0.05 to 1 mu M, with a detection limit of 41 nM, and detect NAD(+)from 0.01 to 1 mu M, with a detection limit of 6.7 nM. Furthermore, ligase-specific dependence of different cofactors provides good selectivity for the detection platform. As a result, the new platform has a broad spectrum of applications both in bioanalysis and biomedical fields.