A tissue-like neurotransmitter sensor for the brain and gut.

Neurotransmitters play essential roles in regulating neural circuit dynamics both in the central nervous system as well as at the peripheral, including the gastrointestinal tract1-3. Their real-time monitoring will offer critical information for understanding neural function and diagnosing disease1-3. However, bioelectronic tools to monitor the dynamics of neurotransmitters in vivo, especially in the enteric nervous systems, are underdeveloped. This is mainly owing to the limited availability of biosensing tools that are capable of examining soft, complex and actively moving organs. Here we introduce a tissue-mimicking, stretchable, neurochemical biological interface termed NeuroString, which is prepared by laser patterning of a metal-complexed polyimide into an interconnected graphene/nanoparticle network embedded in an elastomer. NeuroString sensors allow chronic in vivo real-time, multichannel and multiplexed monoamine sensing in the brain of behaving mouse, as well as measuring serotonin dynamics in the gut without undesired stimulations and perturbing peristaltic movements. The described elastic and conformable biosensing interface has broad potential for studying the impact of neurotransmitters on gut microbes, brain-gut communication and may ultimately be extended to biomolecular sensing in other soft organs across the body.

Three-Dimensional Analysis of Particle Distribution on Filter Layers inside N95 Respirators by Deep Learning.

The global COVID-19 pandemic has changed many aspects of daily lives. Wearing personal protective equipment, especially respirators (face masks), has become common for both the public and medical professionals, proving to be effective in preventing spread of the virus. Nevertheless, a detailed understanding of respirator filtration-layer internal structures and their physical configurations is lacking. Here, we report three-dimensional (3D) internal analysis of N95 filtration layers via X-ray tomography. Using deep learning methods, we uncover how the distribution and diameters of fibers within these layers directly affect contaminant particle filtration. The average porosity of the filter layers is found to be 89.1%. Contaminants are more efficiently captured by denser fiber regions, with fibers <1.8 µm in diameter being particularly effective, presumably because of the stronger electric field gradient on smaller diameter fibers. This study provides critical information for further development of N95-type respirators that combine high efficiency with good breathability.

In Vivo Polymerization ("Hard-Wiring") of Bioanodes Enables Rapid Start-Up and Order-of-Magnitude Higher Power Density in a Microbial Battery.

For microbial electrochemical technologies to be successful in the decentralized treatment of wastewater, steady-state power density must be improved and cost must be decreased. Here, we demonstrate in vivo polymerization ("hard-wiring") of a microbial community to a growing layer of conductive polypyrrole on a sponge bioanode of a microbial battery, showing rapid biocatalytic current development (∼10 times higher than a sponge control after 4 h). Moreover, bioanodes with the polymerized inoculant maintain higher steady-state power density (∼2 times greater than the control after 28 days). We then evaluate the same hard-wired bioanodes in both a two-chamber microbial fuel cell and microbial battery with a solid-state NaFeIIFeIII(CN)6 (Prussian Blue) cathode, showing approximately an order-of-magnitude greater volumetric power density with the microbial battery. The result is a rapid start-up, low-cost (no membrane or platinum catalyst), and high volumetric power density system (independent of atmospheric oxygen) for harvesting energy and carbon from dilute organics in wastewater.

Simethicone improves bowel cleansing with low-volume polyethylene glycol: a multicenter randomized trial.

BACKGROUND AND STUDY AIMS: For bowel preparation, using a reduced volume of polyethylene glycol (PEG) solution without influencing its effectiveness would be preferable. While simethicone shows great potential as an adjunctive agent, data on its use are limited. We aimed to clarify whether simethicone added to low-volume PEG solution improved bowel cleansing. PATIENTS AND METHODS : Consecutive adult patients registered for colonoscopy were recruited from seven medical centers in South China between 15 April and 15 July 2015 and prospectively randomized into two groups: 2 L PEG (conventional group) and 2 L PEG plus simethicone (simethicone group). The primary endpoint was the effectiveness of bowel cleansing according to the Boston Bowel Preparation Scale (BBPS). Secondary endpoints included cecal intubation time, adenoma detection rate (ADR), patient safety and compliance, and adverse events. RESULTS : We included 290 and 289 patients in the conventional and simethicone groups, respectively, for analysis. The proportion with acceptable bowel cleansing (BBPS ≥ 6) was significantly higher in the simethicone group than in the conventional group (88.2 % vs. 76.6 %; P < 0.001). The mean (SD) BBPS score was significantly lower in the conventional group (6.5 [1.8] vs. 7.3 [1.7]; P < 0.001), as was the bubble score (2.5 [0.7] vs. 2.8 [0.5]; P < 0.001). The average cecal intubation time was significantly shorter in the simethicone group (6.3 [3.1] vs. 7.5 [5.1] minutes; P < 0.001). The ADR in the right colon was higher in the simethicone group than in the conventional group (16.6 % vs. 10.3 %; P = 0.03). Safety and compliance, including the taste, smell, and dosage of PEG, were similar for both groups. CONCLUSIONS: Simethicone added to low-volume PEG solution improves bowel-cleansing efficacy, with similar safety and compliance, shorter cecal intubation time, and higher ADR.

Attentional bias modification in reducing test anxiety vulnerability: a randomized controlled trial.

BACKGROUND: A tendency to selectively process a threat to positive information may be involved in the etiology of anxiety disorders. The aim of this study is to examine whether attentional bias modification (ABM) can be used to modify high test-anxiety individuals' attention to emotional information and whether this change is related to anxiety vulnerability. METHODS: Seventy-seven undergraduates were included: 28 individuals received a 5-day modified dot probe task as ABM training, 29 individuals received a 5-day classic dot probe task as placebo, and 20 individuals did not receive an intervention between the two test sections. In addition to the measure of biased attention, salivary α-amylase (sAA) and the visual analogue scale of anxiety were assessed as emotional reactivity to stress. RESULTS: A repeated measurement of variance analysis and paired sample t-test indicated that the ABM group showed a significant change in attentional bias scores after the 5-day training, whereas there were no changes in the attentional bias scores in the placebo or waiting list groups. Importantly, anxiety vulnerability with attention to threats was significantly decreased in the training group. CONCLUSIONS: These results suggest that attentional bias toward threat stimuli may play an important role in anxiety vulnerability. The attentional bias modification away from the threat is effective for the individuals preparing for an exam. TRIAL REGISTRATION: This trial was retrospectively registered on June 22, 2017 with the registration number ChiCTR-IOR-17011745 and the title 'Attentional Bias in high anxiety individuals and its modification'.

Restoration of mandibular bone defects with demineralized bone matrix combined with three-dimensional cultured bone marrow-derived mesenchymal stem cells in minipig models.

Mandibular defects, caused by congenital, pathological or iatrogenic insults, can significantly affect patient quality of life. The reconstruction of mandible has recently gained the interest of clinical and tissue engineering researchers. The purpose of this study was to evaluate the effectiveness of three-dimensional (3-D) cultured autologous grafts prepared using bone marrow-derived mesenchymal stem cells (BMSCs) combined with demineralized bone matrix (DBM) scaffolds for the restoration of mandibular defects. Cylindrical defects were created in the mandibular body of minipigs and filled with 3D-cultured BMSCs/DBM autografts, 2D-cultured BMSCs/DBM autografts, DBM material (without cells), or were left unfilled (blank). Using computed tomographic (CT) imaging and histological staining, we found that treatment of mandibular defects using 3-D cultured BMSCs/DBM autografts offered improvements in bone formation over both 2-D cultured autografts and cell-free DBM scaffolds. We found increased osteoid formation in 3D and 2D cultures, with more osteogenic cells present in the 3D constructs. We suggest that 3-D cultured homograft BMSCs combined with DBM scaffolds represents a new strategy for bone reconstruction, with potential future clinical applicability.

[Chemcial constituents of Eclipta prostrata].

A total of twenty-two compounds were isolated from the 95% EtOH extract of Eclipta prostrata by various purification steps, and their structures were established as ecliptalignin A (1)，ecliptasaponin Ⅰ (2), ecliptasaponin Ⅱ (3), echinocystic acid (4), 3-oxo-16α-hydroxy-olean-12-en-28-oic acid (5), acacetin-7-O-rutinoside (6), luteoloside (7), apigenin (8), luteolin (9), acacetin (10), skullcapflavone Ⅱ (11), kaempferol (12), kaempferide (13), quercetin (14), 4',7-dihydroxyl-3',6'-dimethoxylisoflavone-7-O-glucoside (15), ecliptal (16), 5-hydroxymethyl-(2,2',5',2″)-terthienyl tiglate (17), psoralen (18), isopsoralen (19), wedelolactone (20), crinumaquine (21), and 2,3,9,12-tetramethoxyprotoberberine (22) mainly based on the spectroscopic techniques, of which 1 was a new lignin analogue, and 5, 6, 10-13, 15, 18, 19, 21 and 22 were isolated form this plant for the first time.

Saliva and Plasma Monohydroxycarbamazepine Concentrations in Pediatric Patients With Epilepsy.

BACKGROUND: Monohydroxycarbamazepine (MHD, 10-hydroxy-carbamazepine) is the main active metabolite of oxcarbazepine (OXC). The present study aims to investigate the relationship between plasma and saliva concentrations of MHD in Chinese children with epilepsy. METHODS: Plasma and saliva samples were collected and MHD levels were measured by high-performance liquid chromatography system. Linear regression analysis was conducted between the dose of OXC and saliva concentrations, between the dose of OXC and plasma concentrations, and between the saliva concentrations and plasma concentrations. Student's t-test was used for unpaired data. A one-way analysis of variance was used for analyzing co-medication in subgroups of patients. RESULTS: A total of 58 blood samples and 58 saliva samples were obtained from 52 pediatric epileptic patients, with a median age of 5.67 years (0.58-15 years, 23 males and 29 females). There was an apparent positive correlation between the plasma and saliva MHD concentrations [Y = 0.77x - 0.85 (n = 58), R = 0.908, P < 0.01]. MHD plasma and saliva concentrations were positively correlated to daily drug dose (r = 0.461 and 0.417; P < 0.01 respectively). The saliva/plasma MHD ratio was around 0.71 and had no significant difference with age, gender, and combined medications. When data were analyzed for subgroups (one group taking OXC as monotherapy, the second group taking OXC in add-on with non-enzyme-inducing antiepileptic drugs, and the third group taking OXC in add-on with hepatic-enzyme-inducing antiepileptic drugs or moderate inducers), no significant difference was found between plasma and saliva MHD concentrations in all the above 3 groups. CONCLUSIONS: High correlation between plasma and saliva MHD levels supported the use of saliva as an alternative to plasma for OXC monitoring in children with epilepsy.

Decitabine nanoconjugate sensitizes human glioblastoma cells to temozolomide.

In this study, we developed and characterized a delivery system for the epigenetic demethylating drug, decitabine, to sensitize temozolomide-resistant human glioblastoma multiforme (GBM) cells to alkylating chemotherapy. A poly(lactic-co-glycolic acid) (PLGA) and poly(ethylene glycol) (PEG) based nanoconjugate was fabricated to encapsulate decitabine and achieved a better therapeutic response in GBM cells than that with the free drug. After synthesis, the highly efficient uptake process and intracellular dynamics of this nanoconjugate were monitored by single-molecule fluorescence tools. Our experiments demonstrated that, under an acidic pH due to active glycolysis in cancer cells, the PLGA-PEG nanovector could release the conjugated decitabine at a faster rate, after which the hydrolyzed lactic acid and glycolic acid would further acidify the intracellular microenvironment, thus providing positive feedback to increase the effective drug concentration and realize growth inhibition. In temozolomide-resistant GBM cells, decitabine can potentiate the cytotoxic DNA alkylation by counteracting cytosine methylation and reactivating tumor suppressor genes, such as p53 and p21. Owing to the excellent internalization and endolysosomal escape enabled by the PLGA-PEG backbone, the encapsulated decitabine exhibited a better anti-GBM potential than that of free drug molecules. Hence, the synthesized nanoconjugate and temozolomide could act in synergy to deliver a more potent and long-term antiproliferative effect against malignant GBM cells.

Understanding the role of different conductive polymers in improving the nanostructured sulfur cathode performance.

Lithium sulfur batteries have brought significant advancement to the current state-of-art battery technologies because of their high theoretical specific energy, but their wide-scale implementation has been impeded by a series of challenges, especially the dissolution of intermediate polysulfides species into the electrolyte. Conductive polymers in combination with nanostructured sulfur have attracted great interest as promising matrices for the confinement of lithium polysulfides. However, the roles of different conductive polymers on the electrochemical performances of sulfur electrode remain elusive and poorly understood due to the vastly different structural configurations of conductive polymer-sulfur composites employed in previous studies. In this work, we systematically investigate the influence of different conductive polymers on the sulfur cathode based on conductive polymer-coated hollow sulfur nanospheres with high uniformity. Three of the most well-known conductive polymers, polyaniline (PANI), polypyrrole (PPY), and poly(3,4-ethylenedioxythiophene) (PEDOT), were coated, respectively, onto monodisperse hollow sulfur nanopsheres through a facile, versatile, and scalable polymerization process. The sulfur cathodes made from these well-defined sulfur nanoparticles act as ideal platforms to study and compare how coating thickness, chemical bonding, and the conductivity of the polymers affected the sulfur cathode performances from both experimental observations and theoretical simulations. We found that the capability of these three polymers in improving long-term cycling stability and high-rate performance of the sulfur cathode decreased in the order of PEDOT > PPY > PANI. High specific capacities and excellent cycle life were demonstrated for sulfur cathodes made from these conductive polymer-coated hollow sulfur nanospheres.

Efficacy of Antibiotic Bone Cement in the Treatment of Burkholderia cepacia Infection After Spinal Internal Fixation Surgery: Case Report and Literature Review.

BACKGROUND: In recent years, the number of spinal internal fixation operations has increased significantly, correlating with an elevated risk of postoperative surgical site infection and a rising incidence rate. While the conventional treatment approach involves surgical debridement combined with antibiotic administration, there is a notable gap in reported strategies for Burkholderia cepacia infection and patients exhibiting multidrug resistance. METHODS: Surgical site infection occurred in a patient following internal fixation surgery for thoracic vertebral fractures. Despite the application of systemic antibiotics and regular dressing changes, no improvement was observed. Bacterial culture and drug sensitivity experiments revealed a multidrug-resistant Burkholderia cepacia infection. Two comprehensive debridement procedures were performed along with continuous post-operative irrigation combined with antibiotic administration; however, no significant improvement was observed. The patient's infection was significantly controlled following treatment with vancomycin loaded bone cement. RESULTS: Following spinal internal fixation surgery, the management of a B. cepacian infection with multidrug resistance presented a significant challenge, despite the application of debridement procedures and systemic antibiotics. In this case, after 20 days of treatment with vancomycin-loaded bone cement, the patient's C-reactive protein level decreased to 54 mg/L, was normalized by February, and normal levels were maintained in the surgical area 1 month and 6 months after bone cement removal. CONCLUSIONS: The use of vancomycin-loaded bone cement proves effective in treating postoperative B. cepacian infection in a multidrug-resistant case following spinal internal fixation surgery.

Hybrid silicon nanocone-polymer solar cells.

Recently, hybrid Si/organic solar cells have been studied for low-cost Si photovoltaic devices because the Schottky junction between the Si and organic material can be formed by solution processes at a low temperature. In this study, we demonstrate a hybrid solar cell composed of Si nanocones and conductive polymer. The optimal nanocone structure with an aspect ratio (height/diameter of a nanocone) less than two allowed for conformal polymer surface coverage via spin-coating while also providing both excellent antireflection and light trapping properties. The uniform heterojunction over the nanocones with enhanced light absorption resulted in a power conversion efficiency above 11%. Based on our simulation study, the optimal nanocone structures for a 10 µm thick Si solar cell can achieve a short-circuit current density, up to 39.1 mA/cm(2), which is very close to the theoretical limit. With very thin material and inexpensive processing, hybrid Si nanocone/polymer solar cells are promising as an economically viable alternative energy solution.

Advances in Microgravity Directed Tissue Engineering.

Tissue engineering aims to generate functional biological substitutes to repair, sustain, improve, or replace tissue function affected by disease. With the rapid development of space science, the application of simulated microgravity has become an active topic in the field of tissue engineering. There is a growing body of evidence demonstrating that microgravity offers excellent advantages for tissue engineering by modulating cellular morphology, metabolism, secretion, proliferation, and stem cell differentiation. To date, there have been many achievements in constructing bioartificial spheroids, organoids, or tissue analogs with or without scaffolds in vitro under simulated microgravity conditions. Herein, the current status, recent advances, challenges, and prospects of microgravity related to tissue engineering are reviewed. Current simulated-microgravity devices and cutting-edge advances of microgravity for biomaterials-dependent or biomaterials-independent tissue engineering to offer a reference for guiding further exploration of simulated microgravity strategies to produce engineered tissues are summarized and discussed.

Sunlight filtered via translucent-colored polyvinyl chloride sheets enhanced the light absorption capacity and growth of Arthrospira platensis cultivated in a pilot-scale raceway pond.

In this research, the effects of filtered sunlight traveling through translucent-colored polyvinyl chloride (PVC) sheets on the photoconversion efficiency of Arthrospira platensis are investigated. Filtered sunlight improves the phycobilisome's capacity to completely absorb and transport it to intracellular photosystems. Findings indicated that filtered sunlight via orange-colored PVC sheet increased biomass dry weight by 21% (2.80 g/L), while under blue-colored PVC sheet decreased by 32% (1.49 g/L), when compared with translucent-colored (control) PVC sheet (2.19 g/L) after 120 h of culture. The meteorological conditions during the 1st week of cultivation reported higher light flux than the subsequent weeks. Furthermore, sunlight filtered through orange PVC sheet enhanced protein, allophycocyanin, phycocyanin, chlorophyll-a and carotenoids synthesis by 13%, 15%, 13%, 22%, and 27%, respectively. This practical and inexpensive solar radiation filtration system supports large-scale production of tailored bioactive compounds from microalgae with high growth rate.

Expansion microscopy using a single anchor molecule for high-yield multiplexed imaging of proteins and RNAs.

Expansion microscopy (ExM), by physically enlarging specimens in an isotropic fashion, enables nanoimaging on standard light microscopes. Key to existing ExM protocols is the equipping of different kinds of molecules, with different kinds of anchoring moieties, so they can all be pulled apart from each other by polymer swelling. Here we present a multifunctional anchor, an acrylate epoxide, that enables proteins and RNAs to be equipped with anchors in a single experimental step. This reagent simplifies ExM protocols and reduces cost (by 2-10-fold for a typical multiplexed ExM experiment) compared to previous strategies for equipping RNAs with anchors. We show that this united ExM (uniExM) protocol can be used to preserve and visualize RNA transcripts, proteins in biologically relevant ultrastructures, and sets of RNA transcripts in patient-derived xenograft (PDX) cancer tissues and may support the visualization of other kinds of biomolecular species as well. uniExM may find many uses in the simple, multimodal nanoscale analysis of cells and tissues.

Three-dimensional carbon nanotube-textile anode for high-performance microbial fuel cells.

Microbial fuel cells (MFCs) harness the metabolism of microorganisms, converting chemical energy into electrical energy. Anode performance is an important factor limiting the power density of MFCs for practical application. Improving the anode design is thus important for enhancing the MFC performance, but only a little development has been reported. Here, we describe a biocompatible, highly conductive, two-scale porous anode fabricated from a carbon nanotube-textile (CNT-textile) composite for high-performance MFCs. The macroscale porous structure of the intertwined CNT-textile fibers creates an open 3D space for efficient substrate transport and internal colonization by a diverse microflora, resulting in a 10-fold-larger anolyte-biofilm-anode interfacial area than the projective surface area of the CNT-textile. The conformally coated microscale porous CNT layer displays strong interaction with the microbial biofilm, facilitating electron transfer from exoelectrogens to the CNT-textile anode. An MFC equipped with a CNT-textile anode has a 10-fold-lower charge-transfer resistance and achieves considerably better performance than one equipped with a traditional carbon cloth anode: the maximum current density is 157% higher, the maximum power density is 68% higher, and the energy recovery is 141% greater.

Graphene-wrapped sulfur particles as a rechargeable lithium-sulfur battery cathode material with high capacity and cycling stability.

We report the synthesis of a graphene-sulfur composite material by wrapping poly(ethylene glycol) (PEG) coated submicrometer sulfur particles with mildly oxidized graphene oxide sheets decorated by carbon black nanoparticles. The PEG and graphene coating layers are important to accommodating volume expansion of the coated sulfur particles during discharge, trapping soluble polysulfide intermediates, and rendering the sulfur particles electrically conducting. The resulting graphene-sulfur composite showed high and stable specific capacities up to ∼600 mAh/g over more than 100 cycles, representing a promising cathode material for rechargeable lithium batteries with high energy density.

Modified percutaneous transhepatic variceal embolization with 2-octylcyanoacrylate for bleeding gastric varices: long-term follow-up outcomes.

OBJECTIVE: The objective of our study was to evaluate the long-term efficacy and safety of a modified percutaneous transhepatic variceal embolization procedure with 2-octylcyanoacrylate (2-OCA) in the treatment of gastric variceal bleeding. MATERIALS AND METHODS: From January 2003 to December 2008, 71 patients with a history of gastric variceal bleeding underwent modified percutaneous transhepatic variceal embolization with 2-OCA in our hospital: 12 patients with acute gastric variceal bleeding underwent emergency obliteration and the remaining 59 patients with recent variceal bleeding underwent modified percutaneous transhepatic variceal embolization as a secondary prophylaxis. The initial hemostasis rate, rebleeding rate, survival rate, and complications were evaluated. RESULTS: Complete obliteration--that is, all the gastric varices and their feeding veins were obliterated--was achieved after the percutaneous transhepatic variceal embolization procedure in 67 patients (94.4%). Acute variceal bleeding was arrested after the procedure in all 12 patients (100%). The mean follow-up period was 24.2 ± 12.4 (SD) months (range, 6-62 months). During the follow-up period, the cumulative probability of remaining free of gastric variceal rebleeding in patients with complete obliteration was 100%, 88.2%, and 88.2% at 1, 3, and 5 years after the procedure, respectively. Follow-up CT revealed that the modified percutaneous transhepatic variceal embolization procedure with 2-OCA can achieve long-lasting obliteration in the entire varices and in all the feeding veins. The cumulative survival rates at 1, 3, and 5 years after the procedure were 96.9%, 68.9%, and 53.7%. No severe complications occurred after the procedure. CONCLUSION: The modified percutaneous transhepatic variceal embolization with 2-OCA is considered to be an effective and safe method for the extensive and permanent obliteration of both gastric varices and their feeding veins.

Fluorescent conjugated polyfluorene with pendant lactopyranosyl ligands for studies of Ca(2+)-mediated carbohydrate-carbohydrate interaction.

A well-defined fluorescent conjugated polyfluorene with pendant lactopyranosyl ligands was easily prepared through Cu(I)-catalyzed azide/alkyne "click" ligation and Suzuki coupling polymerization. As a fluorescent multivalent model system of glycoconjugates, the polymer was first used for studies of metal ion-mediated carbohydrate-carbohydrate interaction based on fluorescence spectroscopy. A significant fluorescence quenching of the lactosyl-bearing polyfluorene was observed upon addition of calcium ion, which is attributed to the polymer aggregation derived from Ca(2+)-mediated complex formation. Dynamic light scattering can also prove Ca(2+)-induced aggregation of the polymer based on determination of the corresponding hydrodynamic diameters. The calcium-mediated lactose-lactose interaction was reversible when treated with EDTA. In control studies, Ca(2+)-induced fluorescence quenching can not be observed for cellobiosyl- or galactosyl-functionalized polymer analogues, which show that specific sugar structures are critical for carbohydrate-metal complex formation.

Calcium-siRNA Nanocomplexes Optimized by Bovine Serum Albumin Coating Can Achieve Convenient and Efficient siRNA Delivery for Periodontitis Therapy.

PURPOSE: Reducing toxicity, immunogenicity, and costs of small interfering RNAs (siRNA) carrier materials are key goals for RNA interference (RNAi) technology transition from bench to bed. Recently, calcium ions (Ca2+) have garnered attention as a novel, alternative material for delivering siRNA to cells. However, the tolerance for Ca2+ concentration varies in different cell types, which has limited its applications in vivo. Bovine serum albumin (BSA) can bind to Ca2+ through chelation. Moreover, BSA is a favorable coating material for nanoparticles owing to its excellent biocompatibility. Therefore, we hypothesized that coating Ca2+-siRNA with BSA helps buffer Ca2+ toxicity in vivo. METHODS: BSA-Ca2+-siRNA nanoparticles were prepared, and the size, shape, encapsulation, and release efficiency were characterized using atomic force microscopy, scanning electronic microcopy, and gel electrophoresis. Binding nanoparticles were evaluated using attenuated total reflection-Fourier-transform infrared spectroscopy. The cellular uptake, intracellular release, cytotoxicity, and gene knockdown of nanoparticles were evaluated in periodontal ligament stem cells (PDLSCs) using laser-scanning confocal microscope, flow cytometry, and real-time quantitative polymerase chain reaction. RESULTS: BSA and Ca2+-siRNA could form a stable nano-scale complex (~140 nm in diameter). The nanocomplexes could maintain siRNA release for more than 1 week in neutral phosphate-buffered saline (PBS) and could induce accelerated degradation in acidic PBS (pH 5.0). The nanoparticles were taken up by the cells, primarily through macropinocytosis, and were then released intracellularly through the acidification of endosomes/lysosomes. Importantly, the BSA-Ca2+ carrier had high transfection efficiency and biocompatibility both in vitro and in vivo. To demonstrate the therapeutic potential of our BSA coating-optimized Ca2+-siRNA technology, we showed that BSA-Ca2+-siWWP1 complexes strongly enhanced the osteogenic differentiation of inflammatory PDLSCs. CONCLUSION: BSA-Ca2+ could potentially be used for siRNA delivery, which is not only highly efficient and cost-effective but also biocompatible to host tissues owing to the BSA coating.