Label-free trace detection of bio-molecules by liquid-interface assisted surface-enhanced Raman scattering using a microfluidic chip

Surface-enhanced Raman scattering(SERS),owing to its high sensitivity based on localized surface plasmon resonance of nanostructured metals,is recently attracting much attention to be used for biotechnology,such as cell imaging and tumor therapy.On the other hand,the trace detection of bio-molecules with large molecular weight is still challenging because the troublesome treatment of SERS substrate using coupling or cross-linking agents is required.In this paper,we apply liquid interface assisted SERS(LI-SERS)method,which provides unique features of collection and self-immobilization of analyte molecules on the SERS substrate,to realize the label-free trace detection of bio-molecules with detection limits of pM~fM.Specifically,deoxyribonucleic acid(DNA)discrimination and quantitative detection ofβ-Amyloid(Aβ)in trace-concentration are demonstrated to illustrate the ultrahigh sensitivity and versatility of the LI-SERS method.The results suggest LI-SERS is promising for the early-stage diagnosis of diseases such as virus infection and Alzheimer's disease.

Trojan horses in tumor:engineered pyroelectric and photodynamic nanocomposites for NIR-induced cell apoptosis and tumor growth inhibition

It is desirable but always challenging to develop a cutting-edge tumor treatment strategy with high therapeutic efficacy,lesiontargeted precision and mild accessibility.Compared to traditional treatment modalities,photodynamic therapy has been widely studied since the generation of reactive oxygen species(ROS)at cancerous lesions unprecedentedly offers a convenient approach for localized tumor eliminations.Nevertheless,the consumption of oxygen for ROS production in a hypoxic tumor microenvironment has dramatically limited its feasibility and efficacy.Herein,the engineered nanocomposites of BTO@PDA-ICGHA with photodynamic and pyroelectric performances have been fabricated and applied to the photodynamic-pyroelectric dynamic treatments.The continuing ROS production derived from intracellular oxygen(O_(2))and water(H_(2)O)by laser irradiation contributed to the superb tumor cell apoptosis and significant tumor growth inhibition.Thus,this study has validated a new concept by depositing the engineered nanocomposites at the tumor just like Trojan horses,facilitating ROS release as killers and exerting the NIR-induced cell apoptosis and tumor growth inhibition with high therapeutic efficiency and expectable translational perspectives.