Preliminary Studies on Evaluation and Change Trends of Dominant Components in New Types of Tobacco Sheets by Thick Pulp Process

[Objectives]This study was conducted to deeply understand the effects of production process on the quality of new types of tobacco sheets with different flavors.[Methods]Based on the pilot production process of thick pulp method,four different flavors of tobacco sheets were sampled at several links in the production process,for the detection of the contents of the main components in the samples,including propylene glycol,glycerol,menthol and glyceryl triacetate,so as to explore the change trends of various components in the thick pulp process.[Results]The change laws of propylene glycol and glycerol contents had a very high similarity,showing a trend of first decreasing and increasing then.The changes of menthol content and glyceryl triacetate content were greatly affected by the specific flavor formula.As one of the indexes of the new tobacco evaluation system,the alcohol-to-ester ratio data need to be further improved in the actual production and application process.[Conclusions]This study provides basic data support for improving the quality of tobacco sheets.

NIR-activated nanosystems with self-modulated bacteria targeting for enhanced biofilm eradication and caries prevention

The efficacious delivery of antimicrobial drugs to intractable oral biofilms remains a challenge due to inadequate biofilm penetration and lack of pathogen targeting.Herein,we have developed a microenvironment-activated poly(ethylene glycol)(PEG)-sheddable nanoplatform to mediate targeted delivery of drugs into oral biofilms for the efficient prevention of dental caries.The PEGylated nanoplatform with enhanced biofilm penetration is capable of deshielding the PEG layer under slightly acidic conditions in a PEG chain length-dependent manner to re-expose the bacteria-targeting ligands,thereby facilitating targeted codelivery of ciprofloxacin(CIP)and IR780 to the bacteria after accumulation within biofilms.The nanoplatform tends to induce bacterial agglomeration and suffers from degradation in the acidic oral biofilm microenvironment,triggering rapid drug release on demand around bacterial cells.The self-modulating nanoplatform under near-infrared(NIR)irradiation accordingly displays greatly augmented potency in oral biofilm penetration and disruption compared with drugs alone.Topical oral treatment with nanoplatforms involving synergetic pharmacological and photothermal/photodynamic trinary therapy results in robust biofilm dispersion and efficacious suppression of severe tooth decay in rats.This versatile nanoplatform can promote local accumulation and specific drug transport into biofilms and represents a new paradigm for targeted drug delivery for the management of oral biofilm-associated infections.