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Unbiased metagenomic sequencing is conceptually well-suited for first-line infectious disease diagnostics because it does not require guesswork on the causative organism and can cover all known and unknown infectious entities other than prions. However, costs, turnaround time and human background reads in complex biofluids such as plasma stand in the way of more widespread deployment. Many protocols also require separate library preparations for DNA and RNA analytes, increasing the costs for detection. In this study, we developed a rapid unbiased metagenomics next-generation sequencing (mNGS) workflow that addresses these issues with a human background depletion kit (HostEL) and a library preparation kit that processes DNA and RNA simultaneously (AmpRE). In our analytical validation of the HostEL workflow, we were able to enrich and detect the signal from bacteria and fungi standards spiked in at physiological levels in plasma with low-depth sequencing (< 1 million reads). Our clinical validation also shows that 93% of plasma samples agreed with the clinical diagnostic test results when the diagnostic qPCR had a Ct < 33. The effect of different sequencing times was evaluated with the 19-hour iSeq 100 paired end run, a more clinically palatable simulated iSeq 100 truncated run and the rapid 7-hour MiniSeq platform. Significantly, our results demonstrate the ability to detect both DNA and RNA pathogens with low-depth sequencing. In conclusion, we demonstrate that iSeq 100 and MiniSeq platforms are compatible with unbiased low-depth metagenomics identification with the HostEL and AmpRE workflow and can be chosen based on required turnaround times.

(-)-Epigallocatechin-gallate octaacetate (pro-EGCG), a prodrug of epigallocatechin-gallate (EGCG), has been used for pre-clinical study for the treatment of endometriosis. A validated analytical method has been developed for the determination of plasma pro-EGCG and its metabolites after oral administration using ultra-performance-liquid-chromatography coupled to quadrupole-time-of-flight-mass-spectrometry (UPLC-Qtof-MS). This method is more robust, rapid, sensitive, simpler, and able to detect pro-EGCG metabolites compared to our previous method. Pro-EGCG in the plasma was stabilized from rapid degradation by formic acid, extracted by isopropanol/methyl-tert-butyl ether mixture, separated by UPLC core column, and quantified by an exact mass method with Qtof-MS. The lower limit of quantification (LLOQ), intra-day and inter-day precision, and accuracy for the range of 0.01–2.5 μg/mL were within acceptable limits. The sensitivity was improved by 25 folds using pro-EGCG ammonium adduct [M + NH4]+. This is the first report on the pharmacokinetics of oral administration with maximum-concentration (Cmax) was 0.067 ± 0.04 μg/mL, time-of-maximum-concentration (Tmax) was 1.33 h, area-under-curve (AUC) was 0.20 ± 0.05 h × µg/mL, and elimination-rate was 0.20 ± 0.11 hr−1. The pharmacokinetic profiles of pro-EGCG metabolites, (-)-epigallocatechin-gallate (EGCG) diacetates and EGCG triacetates, were also presented. This method is robust, rapid, and sensitive for the pharmacokinetic study of pro-EGCG and metabolites.

Retinal diseases, such as age-related macular degeneration and diabetic retinopathy, are the leading causes of blindness worldwide. The mainstay of treatment for these blinding diseases remains to be surgery, and the available pharmaceutical therapies on the market are limited, partially owing to various biological barriers in hindering the delivery of therapeutics to the retina. The nanoparticulate drug delivery system confers the capability for delivering therapeutics to the specific ocular targets and, hence, potentially revolutionizes the current treatment landscape of retinal diseases. While the research to date indicates the enormous therapeutics potentials of the nanoparticulate delivery systems, the successful translation of these systems from the bench to bedside is challenging and requires a combined understanding of retinal pathology, physiology of the eye, and particle and formulation designs of nanoparticles. To this end, the review begins with an overview of the most prevalent retinal diseases and related pharmacotherapy. Highlights of the current challenges encountered in ocular drug delivery for each administration route are provided, followed by critical appraisal of various nanoparticulate drug delivery systems for the retinal diseases, including their formulation designs, therapeutic merits, limitations, and future direction. It is believed that a greater understanding of the nano-biointeraction in eyes will lead to the development of more sophisticated drug delivery systems for retinal diseases.

Recent advances in crystal engineering by cocrystallization have offered a promising approach for tackling undesirable physicochemical properties of drug substances. In this study, various structur...

Herein, for the first time, we report the synthesis, preparation, and characterization of fatty acid-conjugated poly(ethylene glycol)-block-poly(epsilon-caprolactone) nanoparticles (FA-NPs), with the ultimate goal of improving drug delivery to the brain. These nanoparticles had a nano-size ( 5.4 × 105x. They showed moderate stability in serum and exhibited zero-order drug release. As a proof-of-concept, the brain uptake of oleic acid-NPs (OA-NPs) was examined in rats after intravenous injections. Relative to 1% DMSO and PEG-NPs formulations, the OA-NPs enhanced the brain accumulation of the loaded cargo by 4.28 and 1.94x, respectively. Apparently, these nanoparticles hold considerable promise in drug delivery to the brain and their potential applications for disorders of the central nervous system should be explored.

Spherical nucleic acid gold nanoparticles represent a unique nanotechnology in which the spherical arrangement of oligonucleotides enables the nanoparticles to be efficiently internalized into cells expressing scavenger receptors class A (SR-A). Herein, we seek to replace the gold core with a biodegradable polymeric construct and explore their potential applications in targeted drug delivery. Oligonucleotide-conjugated poly(ethylene glycol)-block-poly(e-caprolactone) was synthesized and characterized by 1H NMR and gel electrophoresis. This polymer was applied to fabricate micellar nanoparticles (OLN-NPs) by an anti-solvent method. These nanoparticles have a mean particle size about 58.1nm with a narrow size distribution (PDI

Background and aims Ocular safety/biocompatibility is an essential element of ophthalmic drug delivery. We previously applied poly(ethylene glycol)-block-poly(ɛ-caprolactone) (PEG-b-PCL) micelles to deliver dasatinib for the management of proliferative vitreoretinopathy (PVR) in vitro. Herein, we seek to ascertain the ocular safety/compatibility of blank and dasatinib loaded PEG-b-PCL micelles, which will set the stage for the future in vivo efficacy evaluations and/or clinical translation for PVR or other eye diseases. Methods To access the safety of blank and dasatinib loaded micelles, in vitro cell based assays (LDH cell membrane damage test, SRB cytotoxicity, TEER and permeability of RPE tight junctions), in vivo slit lamp biomicroscopy and optical coherence tomography, Ex vivo histology (H&E staining, GFAP immunofluorescence staining and TUNEL assay) were undertaken. Results Both blank and dasatinib loaded micelles showed remarkable safety profiles at cellular levels. They also caused negligible ocular toxicity/abnormalities up to 28 days post-intravitreal injection in mice. The micelles did not insult the cornea, as demonstrated by slit-lamp biomicroscopy. Ex vivo histology and in vivo optical coherence tomography revealed a normal retinal structure with minimal apoptosis and stresses. Conclusion Taken together, both blank and dasatinib loaded micelles appear to be safe and their applications in drug delivery for eye diseases should be explored.

Drug solubility and permeability are two major challenges affecting oral delivery, the most popular route of drug administration. Polymeric micelles is an emerging technology for overcoming the current oral drug delivery hurdles. Previous study primarily focused on developing new polymers or new micellar systems and a systematic investigation of the impact of the polymer block length on solubility and permeability enhancement; and their subsequent effect on oral bioavailability is lacking. Herein, by using paclitaxel, a poorly soluble P-glycoproteins (P-gp) substrate, as a model, we aim to assess and compare the drug-loaded micelles prepared with two different molecular weight of poly(ethylene glycol)-block-poly(e-caprolactone) (PEG-b-PCL), with the ultimate goal of establishing a strong scientific rationale for proper design of formulations for oral drug delivery. PEG-b-PCL (750:570) (PEG17-b-PCL5) and PEG-b-PCL (5k:10k) (PEG114-b-PCL88) effectively enhanced the solubility of paclitaxel compared to the free drug. PEG-b-PCL (750:570) increased both P-gp and non P-gp substrate cellular uptake and increased the apparent permeability coefficient of a P-gp substrate. In vivo animal study showed that PEG-b-PCL micelles efficiently enhanced the oral bioavailability of paclitaxel. In addition to solubility enhancement, polymer choice also plays a pivotal role in determining the oral bioavailability improvement, probably via permeation enhancement. In conclusion, the knowledge gained in this study enables rational design of polymeric micelles to overcome the current challenges of oral drug delivery and it also provides a basis for future clinical translation of the technology.

Despite significant improvements in the synthesis of templated silica materials, post‐synthesis purification remains highly expensive and renders the materials industrially unviable. In this study this issue is addressed for porous bioinspired silica by developing a rapid room‐temperature solution method for complete extraction of organic additives. Using elemental analysis and N2 and CO2 adsorption, the ability to both purify and controllably tailor the composition, porosity and surface chemistry of bioinspired silica in a single step is demonstrated. For the first time the extraction is modelled using molecular dynamics, revealing that the removal mechanism is dominated by surface‐charge interactions. This is extended to other additive chemistry, leading to a wider applicability of the method to other materials. Finally the environmental benefits of the new method are estimated and compared with previous purification techniques, demonstrating significant improvements in sustainability.