Surface forces between inorganic nanoparticlesand lipid bilayer is of great relevance to biophysics, medicine, and nanobiotechnology. Adsorbed nanoparticles may influence the fluidity of the underlying lipids, which may in turn influence nanoparticle assembly. Herein three types of lipids (DOPC, Tc = -20 C; DMPC, Tc = 23 C, and DPPC, Tc = 41 C) are used, all with the same phosphocholine (PC) headgroup. Gold nanoparticle (AuNP) color change is monitored as a function of lipid phase transition temperature (Tc), surface ligands on AuNPs, and temperature. Liposomes with higher fluidity induce much faster aggregation of AuNPs. Aside from the kinetic aspect of faster diffusion on fluid bilayers, this faster color change is attributed to the local lipid gelation and merging of gelled regions to eliminate the interface between different lipid phases.

Gold nanomaterials have received great interest for their use in cancer theranostic applications over the past two decades. Many gold nanoparticle-based drug delivery system designs rely on adsorbed ligands such as DNA or cleavable linkers to load therapeutic cargo. The heightened research interest was recently demonstrated in the simple design of nanoparticle-drug conjugates wherein drug molecules are directly adsorbed onto the as-synthesized nanoparticle surface. The potent chemotherapeutic, doxorubicin often serves as a model drug for gold nanoparticle-based delivery platforms; however, the specific interaction facilitating adsorption in this system remains understudied. Here, for the first time, we propose empirical and theoretical evidence suggestive of the main adsorption process where (1) hydrophobic forces drive doxorubicin towards the gold nanoparticle surface before (2) cation-π interactions and gold-carbonyl coordination between the drug molecule and the cations on AuNP surface facilitate DOX adsorption. In addition, biologically relevant compounds, such as serum albumin and glutathione, were shown to enhance desorption of loaded drug molecules from AuNP at physiologically relevant concentrations, providing insight into the drug release and in vivo stability of such drug conjugates.

Layered double hydroxide nanoparticles (LDH NPs) have attracted interest as an effective gene delivery vehicle in biomedicine. Recent advances in clinic trials have demonstrated the efficacy of Mg/Fe LDHs for hyperphosphatemia treatment, but their feasibility for gene delivery has not been systematically evaluated. As a starting point, we aimed to study the interaction between oligo-DNA and Mg/Fe LDH NPs. Our investigation revealed the chemisorption mechanism of DNA on Mg/Fe LDH surfaces, wherein the phosphate backbone of the DNA polymer coordinates with the metal cations of the LDH lattice via the ligand-exchange process. This mechanistic insight may facilitate future gene delivery applications using Mg/Fe LDH NPs.

Objective Peritonsillar abscesses (PTAs) are common emergency consultations for otolaryngologists. Medical management alone may offer satisfactory treatment without the risk associated with surgical drainage. Therefore, we performed a systematic review of medical treatment alone compared to surgical drainage for the treatment of PTA. Data Sources MEDLINE, EMBASE, Cochrane CENTRAL, and ClinicalTrials.gov. Review Methods Studies comparing the outcomes of medically treated to surgically treated patients were included. Risk of bias was assessed using the Newcastle-Ottawa Scale. All screening and data extraction were completed by 2 independent reviewers. Meta-analysis was performed using a random-effects model. Subgroup and sensitivity analyses were performed. Results Ten cohort studies and 2 randomized studies were included (ntotal = 33,468). Study quality was low, with only 1 study providing multivariable analysis. The combined rate of treatment failure in patients initially treated with medical management alone was 5.7% compared to 5.5% in the surgical group. There was no statistically significant difference in the odds of treatment failure between interventions through random-effects meta-analysis (odds ratio [OR], 1.10; 95% CI, 0.53-2.26; I 2 = 41%; P = .13). Subgroup analysis excluding pediatric-specific studies revealed similar odds of treatment failure when initially managed with medical intervention (OR, 0.92; 95% CI, 0.56-1.50; P = .39; I 2 = 0%). Conclusion Meta-analysis of available studies demonstrated no difference in odds of treatment failure for patients with PTA managed through medical intervention alone compared to surgical intervention. These findings should be interpreted with caution due to high probability of bias and overall low quality of studies.