Integrated Microwell Array-Based Microfluidic Chip with a Hand-Held Smartphone-Controlled Device for Nucleic Acid Detection.

In this study, we designed a highly integrated microfluidic chip for nucleic acid extraction, amplification, and detection. Magnetic beads, which are used to capture nucleic acids on the chip, are trapped in the microwell arrays in a one-well-one-bead manner after local surface modification of the inner faces of the microwells. On-chip liquid introduction, delivery, and mixing are all carried out manually with one syringe and no other equipment. A hand-held device with precise temperature control and high-quality imaging is developed, which is only 2.3 cubic decimeters in volume and 1.2 kg in weight. Via the use of the Internet for wireless communication, the experiment and data analysis after inserting the chip into the device can be conducted by a smartphone anywhere there is an Internet connection. We carried out reverse transcription loop-mediated isothermal amplification (RT-LAMP) on the chip with the hand-held device. SARS-CoV-2 pseudoviruses are extracted, reverse transcribed, amplified, and detected on the chip with the hand-held device with satisfactory results. Thus, a highly integrated, easy-to-operate, and rapid nucleic acid detection microfluidic chip with a hand-held smartphone-controlled device is proposed, and this new platform for nucleic acid detection shows great potential for mobile point-of-care testing (POCT).

Reference material development for detection of human respiratory syncytial virus using digital PCR.

Nucleic acid testing is a powerful tool for the detection of various pathogens. Respiratory syncytial virus (RSV) is a major cause of acute respiratory infection, especially in young children and infants. To improve the confidence and reliability of nucleic acid testing results for RSV, reference materials (RMs) of both type A and B of RSV were developed by the National Institute of Metrology, China, code numbers NIM-RM 4057 and 4058. The reference material was composed of in vitro transcribed RNA containing the nucleocapsid (N) gene, matrix (M) gene, and partial polymerase (L) gene of RSV. A duplex reverse transcription digital PCR method was established with limit of blank (LoB), limit of detection (LoD) and limit of quantification (LoQ) of 2, 5, and 23 copies per reaction for RSV-A and 4, 8, and 20 copies per reaction for RSV-B. The certified value and expanded uncertainty (U, k = 2) of the two RMs were determined to be (6.1 ± 1.4) × 104 copies/µL for RSV-A and (5.3 ± 1.2) × 104 copies/µL for RSV-B. The developed RMs can be used as standards to evaluate the performance of RSV detection assays.

Establishment of Digital PCR Method and Reference Material for Adenoviruses 40 and 41.

Coinfection with human adenovirus (HAdV) and SARS-CoV-2 has been associated with acute hepatitis in children with unknown etiology. Similar cases have been reported in many countries, and HAdV 40 and HAdV 41 have been identified. The quantification method is established based on digital PCR (dPCR) for HAdV 40/41, which is more convenient for low-concentration virus detection. The limit of detections of HAdV 40/41 dPCR were 4 and 5 copies/µL. Pseudovirus reference material (RM) that contains the highly conserved HEXON gene was developed and quantified with the dPCR method. The assigned values with expanded uncertainty were (1.43 ± 0.35) × 103 copies/µL for HAdV 40 RM and (1.21 ± 0.28) × 103 copies/µL for HAdV 41 RM. The values could be reproduced on multiple platforms. The dPCR method and pseudovirus RMs contribute to the improved accuracy of HAdV 40/41 detection, which is crucial for clinical diagnosis.

Nucleic acid therapy in pediatric cancer.

The overall survival, progress free survival, and life quality of cancer patients have improved due to the advance in minimally invasive surgery, precision radiotherapy, and various combined chemotherapy in the last decade. Furthermore, the discovery of new types of therapeutics, such as immune checkpoint inhibitors and immune cell therapies have facilitated both patients and doctors to fight with cancers. Moreover, in the context of the development in biocompatible and cell type targeting nano-carriers as well as nucleic acid-based drugs for initiating and enhancing the anti-tumor response have come to the age. The treatment paradigms utilization of nucleic acids, including short interfering RNA (siRNA), antisense oligonucleotides (ASO), and messenger RNA (mRNA), can target specific protein expression to achieve the therapeutic effects. Over ten nucleic acid therapeutics have been approved by the FDA and EMA in rare diseases and genetic diseases as well as dozens of registered clinical trails for varies cancers. Though generally less dangerous of pediatric cancers than adult cancers was observed during the past decades, yet pediatric cancers accounted for a significant proportion of child deaths which hurt those family very deeply. Therefore, it is necessary to pay more attention for improving the treatment of pediatric cancer and discovering new nucleic acid therapeutics which may help to improve the therapeutic effect and prognoses in turns to ameliorate the survival period and quality of life for children patient. In this review, we focus on the nucleic acid therapy in pediatric cancers.

Accurate quantification of SARS-CoV-2 RNA by isotope dilution mass spectrometry and providing a correction of reverse transcription efficiency in droplet digital PCR.

The novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 505 million confirmed cases, including over 6 million deaths. Reference materials (RMs) of SARS-CoV-2 RNA played a crucial role in performance evaluation and quality control of testing laboratories. As the potential primary characterization method of RMs, reverse transcription digital PCR (RT-dPCR) measures the copy number of RNA, but the accuracy of reverse transcription (RT) efficiency has yet to be confirmed. This study established a method of enzymatic digestion followed by isotope dilution mass spectrometry (IDMS), which does not require an RT reaction, to quantify in vitro-transcribed SARS-CoV-2 RNA. RNA was digested to nucleotide monophosphate (NMP) within 15 min and analyzed by IDMS within 5 min. The consistency among the results of four different NMPs demonstrated the reliability of the proposed method. Compared to IDMS, the quantitative result of RT-dPCR turned out to be about 10% lower, possibly attributed to the incompleteness of the reverse transcription process. Therefore, the proposed approach could be valuable and reliable for quantifying RNA molecules and evaluating the RT efficiency of RT-based methods.

Resistive pulse sensing device with embedded nanochannel (nanochannel-RPS) for label-free biomolecule and bionanoparticle analysis.

This paper reports an IC-compatible method for fabricating a PDMS-based resistive pulse sensing (RPS) device with embedded nanochannel (nanochannel-RPS) for label-free analysis of biomolecules and bionanoparticles, such as plasmid DNAs and exosomes. Here, a multilayer lithography process was proposed to fabricate the PDMS mold for the microfluidic device, comprising a bridging nanochannel, as the sensing gate. RPS was performed by placing the sensing and excitation electrodes symmetrically upstream and downstream of the sensing gate. In order to reduce the noise level, a reference electrode was designed and placed beside the excitation electrode. To demonstrate the feasibility of the proposed nanochannel-RPS device and sensing system, polystyrene micro- and nanoparticles with diameters of 1µm and 300 nm were tested by the proposed device with signal-to-noise ratios (SNR) ranging from 9.1-30.5 and 2.2-5.9, respectively. Furthermore, a nanochannel with height of 300 nm was applied for 4 kb plasmid DNA detection, implying the potential of the proposed method for label-free quantification of nanoscale biomolecules. Moreover, HeLa cell exosomes, known as a well-studied subtype of extracellular vesicles, were measured and analyzed by their size distribution. The result of the resistive pulse amplitude corresponded well to that of nanoparticle tracking analysis (NTA). The proposed nanochannel-RPS device and the sensing strategy are not only capable of label-free analysis for nanoscale biomolecules and bionanoparticles, but are also cost-effective for large-scale manufacturing.

A tandem giant magnetoresistance assay for one-shot quantification of clinically relevant concentrations of N-terminal pro-B-type natriuretic peptide in human blood.

We report a microfluidic sandwich immunoassay constructed around a dual-giant magnetoresistance (GMR) sensor array to quantify the heart failure biomarker NT-proBNP in human plasma at the clinically relevant concentration levels between 15 pg/mL and 40 ng/mL. The broad dynamic range was achieved by differential coating of two identical GMR sensors operated in tandem, and combining two standard curves. The detection limit was determined as 5 pg/mL. The assay, involving 53 plasma samples from patients with different cardiovascular diseases, was validated against the Roche Cobas e411 analyzer. The salient features of this system are its wide concentration range, low detection limit, small sample volume requirement (50 µL), and the need for a short measurement time of 15 min, making it a prospective candidate for practical use in point of care analysis.

Interlaboratory assessment of quantification of SARS-CoV-2 RNA by reverse transcription digital PCR.

The pandemic of the novel coronavirus disease 2019 (COVID-19) has caused severe harm to the health of people all around the world. Molecular detection of the pathogen, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), played a crucial role in the control of the disease. Reverse transcription digital PCR (RT-dPCR) has been developed and used in the detection of SARS-CoV-2 RNA as an absolute quantification method. Here, an interlaboratory assessment of quantification of SARS-CoV-2 RNA was organized by the National Institute of Metrology, China (NIMC), using in vitro transcribed RNA samples, among ten laboratories on six different dPCR platforms. Copy number concentrations of three genes of SARS-CoV-2 were measured by all participants. Consistent results were obtained with dispersion within 2.2-fold and CV% below 23% among different dPCR platforms and laboratories, and Z' scores of all the reported results being satisfactory. Possible reasons for the dispersion included PCR assays, partition volume, and reverse transcription conditions. This study demonstrated the comparability and applicability of RT-dPCR method for quantification of SARS-CoV-2 RNA and showed the capability of the participating laboratories at SARS-CoV-2 test by RT-dPCR platform.

Left ventricular metabolic remodeling and accompanied dysfunction in type 2 diabetic patients: A 3D speckle tracking analysis.

PURPOSES: The purposes of our study were to determine the risk factors related to metabolic left ventricular remodeling (LVR) in type 2 diabetes mellitus (T2DM) patients and to assess the LV function with different geometry in such population. METHODS: Seventy-eight T2DM patients with normal 2D-LVEF (≥55%) were enrolled and divided into two groups with LV normal geometry (LVN) and with LV remodeling (LVR). The control group was composed of forty age- and sex-matched healthy individuals with LVN. A multifactor logistic regression was used to determine the risk factors for LVR, and their diagnostic values were evaluated using the area under the ROC curves (AUC). Three-dimensional speckle tracking echocardiography (3DSTE) was used to measure LV global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS). RESULTS: Fasting plasma glucose (FPG), hyperlipidemia, and BMI were independently associated with LVR in T2DM patients, and the AUC values were 0.699, 0.697, and 0.732, respectively. The T2DM patients with LVN showed significantly lower GLS than the controls (P < 0.05), whereas the T2DM patients with LVR showed significantly lower GLS, GCS, GAS, and GRS than the T2DM patients with LVN (all P < 0.01). Additionally, GLS, GAS, and GRS values decreased significantly in the T2DM patients with LV hypertrophy than in those with LV concentric remodeling (all P < 0.05). CONCLUSIONS: The routine echocardiography and 3DSTE could be used in combining way to detect the metabolic LV remodeling and accompanied dysfunction in T2DM patients.

Left ventricular structural alterations are accompanied by subclinical systolic dysfunction in type 2 diabetes mellitus patients with concomitant hyperlipidemia: An analysis based on 3D speckle tracking echocardiography.

AIMS: The aims of the current study were to analyze and compare the left ventricular (LV) structure and function in type 2 diabetes mellitus (T2DM) patients with or without hyperlipidemia using conventional echocardiography and real-time three-dimensional speckle tracking echocardiography (3DSTE) and to determine the variables that could affect LV strain values in these patients. METHODS: Eighty-one T2DM patients with normal LVEF (≥55%) were included, 41 of whom had hyperlipidemia as comorbidity. Forty age- and gender-matched healthy volunteers were recruited as the control group. Conventional echocardiography and 3DSTE were performed, and LV global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were measured. RESULTS: Significant differences in two-dimensional LV geometry were found among three groups (P = .015). Compared with the control group, LV remodeling was more prevalent in the patients with T2DM, and LV hypertrophy was most prevalent in the T2DM patients with hyperlipidemia. GLS and GCS values decreased significantly in the T2DM patients without hyperlipidemia relative to the control group (P < .01 and P < .05). The GLS, GCS, GAS, and GRS values in the T2DM patients with hyperlipidemia were all significantly lower than those in the control group (all P < .001) and were also significantly lower than those in the T2DM patients without hyperlipidemia (P < .01 or P < .05). Both fasting plasma glucose (FPG) and hyperlipidemia were independently associated with all strain values in patients with T2DM. CONCLUSIONS: The combination of conventional echocardiography and 3DSTE could detect subclinical LV abnormalities in T2DM patients with or without hyperlipidemia.

An acryl resin-based swellable microneedles for controlled release intradermal delivery of granisetron.

Swellable microneedles (SMNs) are made of hydrogels and can deliver drug with controlled delivery rate by the cross-link density of the hydrogel. In this study, an acryl resin-based SMNs was developed for poorly water-soluble drugs. The making process of the SMNs is very simple and only need 60 min. The SMNs has high mechanical strength and is not easily broken. In-vitro release of SMNs-loaded model drug, granisetron base (GRB), was investigated. The results showed that seven days controlled release of GRB was obtained when SMNs contained pore-foaming agents (1.5% dicalcium phosphate (CaHPO4) and 1.5% polyvinylpyrrolidone (PVP)). The maximum amount delivered into skin was 86.158 ± 7.82% of the initial GRB (2.1 mg) loaded on SMNs preparation. Pharmacokinetics study in rats indicated a dose-dependent profile of plasma GRB concentrations and that the controlled release of 2.1 mg dose was observed for 144 hours. In conclusion, these SMNs provided a potential minimally invasive route for controlled-release systemic delivery of poorly water-soluble drugs.

Association of pulse pressure with left ventricular geometry and function in elderly nonhypertensive patients with diabetes: A 3D speckle tracking echocardiography study.

PURPOSE: The aims of this study were to investigate and compare the left ventricular (LV) geometry and function in elderly nonhypertensive type 2 diabetic patients with normal (NPP, <60 mm Hg) and with high (HPP, ≥60 mmHg) 24-hour pulse pressure, and to explore the independent predictors of LV strain values in these patients. METHODS: A total of 76 elderly nonhypertensive type 2 diabetic patients with normal (≥55%) LV ejection fraction (LVEF) were included, 36 of whom had HPP. The control group included 40 age- and sex-matched healthy volunteers with normal NPP. Conventional echocardiography and three-dimensional speckle-tracking echocardiography (3DSTE) were performed and LV global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were measured. RESULTS: Significant differences in the two-dimensional LV geometry were found among the three groups (p = 0.015), and concentric geometry was most prevalent in the diabetic patients with HPP. The diabetic patients with NPP only showed significantly lower GLS than the controls (p < 0.05). However, the diabetic patients with HPP showed significantly lower LVEF and severely lower strain values in all directions than the controls and the diabetic patients with NPP (p < 0.01or p < 0.05 or p < 0.001). Fasting plasma glucose, HPP, and body mass index were independently associated with all strain parameters in diabetic patients. CONCLUSIONS: The combination of conventional echocardiography and 3DSTE could detect LV subclinical abnormalities in nonhypertensive type 2 diabetic patients with NPP and HPP. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 45:416-425, 2017.

Effects of diagnostic ultrasound-targeted microbubble destruction on the homing ability of bone marrow stromal cells to the kidney parenchyma.

OBJECTIVES: Bone marrow stromal cells (BMSC) transplantation proves successful in treating kidney disease and injury in many studies. However, their reparative capacity is limited by the poor homing ability in vivo, which is decided mainly by the local expression of chemoattractants. Our study explored the mechanical effects of ultrasound targeted microbubble destruction (UTMD) on BMSCs homing ability in treated kidney tissues. METHODS: Rats were injected with red fluorescent protein (RFP)-labelled BMSCs and sonicated with microbubble-mediated ultrasound. Then, we tested kidney micro-environment changes induced and their influence on stem cell homing ability. RESULTS: The results showed that the mechanical effects of UTMD would increase local and transient levels of chemoattractants (i.e. cytokines, integrins and growth factors) in targeted kidney tissues. Transmission electron microscopy showed that vascular endothelial cell was discontinuous in the UTMD group post-treatment, becoming smooth 72 h later. Confocal laser scanning microscopy and RT-PCR showed up to eight times more stem cells in the peritubular regions of experimental kidneys on days 1 and 3 post-treatment compared with the contralateral kidney. CONCLUSIONS: These results confirmed that renal micro-environment changes caused by appropriate UTMD may promote BMSC homing ability toward treated kidney tissues without renal toxicity and cell damage. KEY POINTS: • This experiment showed a feasible strategy in promoting stem cell homing ability. • The treatment uses diagnostic ultrasound during enhancement with IV microbubbles. • A suitable micro-environment was important for targeted stem cell homing and retention. • The method is effective for stem cell homing to kidney diseases. • More work is required with larger animals before potential human trials.

Dissolving microneedle-based intradermal delivery of interferon-α-2b.

The dermal and transdermal delivery of protein pharmaceuticals faces enormous challenges, and at the same time, has very significant potential for the non-invasive treatment of both localized and systemic diseases. To demonstrate the pharmaceutical usefulness of dissolving microneedles (MNs) containing interferon-α-2b (IFN), IFN MNs were prepared using a new method. IFN were encapsulated in MNs with dose from 4.94 ± 0.64 to 23.79 ± 2.48 µg, and in vitro release test showed the efficiency reached 49.2%. After percutaneous administration of IFN MNs to rats, serum IFN levels were measured for 12 h. The peak serum IFN level, maximum drug concentration (Cmax), and the time to reach maximum concentration (Tmax), were 11.58 ± ng/ml and 40 min, respectively, for high-dose MNs group. The area under the curve (AUC) of MNs group was 28.85 ng·h/ml, while intramuscular injection (IM) group with equal dose was 31.17 ng·h/ml. Immunogenicity analysis showed the anti-IFN antibody got back to normal level at ninth week, and there was no difference between male and female rats. IFN MNs showed good stability for 2 months and no damage to the administered rats' skin. The results demonstrated the IFN MNs have a great potential to provide an alternative to IM.

Transesophageal Echocardiography for the Evaluation of Aorto-Left Ventricular Tunnel in Adults, with Follow-ups.

OBJECTIVE: This study aims to compare the diagnostic accuracy of combined two-dimensional (2D) and real time three-dimensional (RT3D) transesophageal echocardiogram (TEE) imaging with the anatomic findings during surgery in adults with aorto-left ventricular tunnel (ALVT). BACKGROUND: ALVT has typically been reported in infants rather than in adults. TEE appears to be a promising method of recognizing the spatial relationship of intracardiac structures. METHODS: Patients underwent comprehensive 2D and RT3DTEE within 1 week preoperative and intraoperative. The TEE images were compared with the surgical findings. RESULTS: Nine patients diagnosed with ALVT using TEE were selected. The operations were successfully performed in 8 patients. The origin of the tunnels diagnosed by TEE was superior to the right coronary sinus (RCS) in 3 patients, superior to the commissure of the left coronary sinus (LCS) and the RCS in 3 patients, inferior to the junction of the LCS and noncoronary sinus (NCS) in 2 patients, and superior to the NCS in 1 patient. The surgical findings confirmed ALVT in 8 patients. The average diameter of the tunnel orifices in the LV or in the aorta measured by TEE versus surgery was 6.15 ± 3.21 mm versus 6.80 ± 3.91 mm (correlation displayed as r = 0.99, P < 0.0001). Seven (78%) patients had mild to severe aortic regurgitation, and 6 (67%) patients had mitral regurgitation. CONCLUSIONS: A combination of 2D and RT3DTEE imaging modalities would be needed to optimally define the anatomy and functional consequences of ALVT in adults.

Controllable coating of microneedles for transdermal drug delivery.

Coated microneedles have been paid much attention recently, and several coating strategies have been developed to address the problems during coating process. However, there are still some unresolved issues, such as, precise control requirements, microneedle substrate contamination and high processing temperature. The purpose of this study was to develop a simple and controllable method to make uniform coatings on microneedles at room temperature. This novel method avoids the contamination of microneedle substrate by providing both the adsorption force of thickener and micro-scale coating film produced by a newly design device. Thickeners were screened to enhance the mass of coatings. The parameters that influence the coatings were tested systematically, which made coating process controllable. Finally, three model drugs were coated onto microneedles to prove the method is applicable more broadly. In addition, insertion experiments were carried out to test the drug delivery feasibility of the coated microneedles. In conclusion, this study presents a simple and controllable method to coat microneedles with small molecular chemical drugs or large proteins for rapid skin drug delivery.

Assessment of left ventricular function by three-dimensional speckle-tracking echocardiography in well-treated type 2 diabetes patients with or without hypertension.

PURPOSE: The aims of this study were to investigate the myocardial deformation in well-treated type 2 diabetes patients with or without hypertension using three-dimensional speckle-tracking echocardiography and to explore variables that could affect myocardial deformation. METHODS: We studied 82 patients with type 2 diabetes and controlled blood glucose, including 46 subjects with diabetes alone and 36 subjects with diabetes and well-controlled hypertension, and 40 age- and gender-matched controls. Left ventricular real-time three-dimensional (3D) full-volume images were recorded and analyzed using online software. The left ventricular ejection fraction, global longitudinal strain (GLS), global circumferential strain, global area strain, and global radial strain were measured and compared. RESULTS: Despite a similar three-dimensional left ventricular ejection fraction, GLS was significantly lower in patients with diabetes only than in controls (p < 0.001). Patients with diabetes and hypertension showed significantly lower systolic strains in all directions than controls and patients with diabetes only (p < 0.001 and p < 0.05, respectively). Multiple regression analysis revealed that fasting plasma glucose and left ventricular end-diastolic volume were significant factors influencing GLS in both diabetic groups. CONCLUSIONS: Early-stage diabetic patients showed an impaired left ventricular strain that was worsened by coexistent hypertension, although blood glucose and blood pressure were well controlled. Three-dimensional speckle-tracking echocardiography was able to detect these subclinical changes.

In vivo thrombolysis with targeted microbubbles loading tissue plasminogen activator in a rabbit femoral artery thrombus model.

The increasingly high incidence of ischemic stroke caused by thrombosis of the arterial vessels is one of the major factors that threaten people's health and lives in the world. The present treatments for thrombosis are unsatisfactory yet. We developed the microbubbles loading tissue plasminogen activator (tPA) and their in vitro thrombolysis efficacy under ultrasound exposure has been proved previously. We tried to investigate their thrombolysis effect in vivo in this present study. Thrombus model was made by clamping bilateral femoral arteries in 70 arteries of 40 rabbits. The targeted tPA-loaded microbubbles were made by lyophilization, taking arginine-glycine-aspartic acid-serine peptide as the targeting ligand. Its thrombolysis efficacy, calculated as count rate and efficiency rate of recanalization, was evaluated by Pearson's χ(2) and One-way ANOVA, respectively. The count rate of recanalization of the targeted tPA-loaded microbubbles under ultrasound exposure (70%) was similar to that of the combination of tPA, microbubbles and ultrasound exposure (80%) (P = 0.61), while its tPA dosage (0.06 mg/kg) was much less than that of latter (0.9 mg/kg). Its efficiency rate of recanalization was the highest among all groups (53.22 ± 40.39%) (P < 0.01). Ultrasound-induced targeted tPA-loaded microbubbles release is a promising thrombolytic method with satisfactory thrombolytic efficacy, lowered tPA dose and potentially decreased hemorrhagic risk.

Industrializable approach for preparing hydrogel microneedles and their application in melanoma treatment.

Microneedles (MNs) technology has been studied in transdermal drug delivery for more than 20 years with hundreds of clinical trials conducted. However, there are currently no commercially available MNs in medicine due to challenges in materials safety, cost-effective fabrication, and large-scale manufacturing. Herein, an approach for rapid and green fabrication of hydrogel microneedles (HMNs) based on infrared irradiation process was proposed for the first time. The optimized formulation consisted of polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP), which acted as cross-linked materials and pore-forming agents, respectively. The manufacturing method involved placing MNs patches under infrared irradiation at 70 °C for 2 min and annealing to obtain HMNs with excellent swelling behavior, mechanical strength, and biocompatibility. When model drugs azelaic acid (AZA) and matrine (MAT) were loaded into HMNs systems, the chemical stability of MAT was significantly improved. Ex vivo transdermal delivery experiments indicated that HMNs could achieve synchronous release of AZA and MAT, and the 24-hour percutaneous permeability rates of both drugs were 73.09 ± 0.48 % and 71.56 ± 1.23 %, respectively. In-vivo pharmacokinetic studies, HMNs administration presented dose-dependent stable blood drug concentrations for both drugs. Additionally, prominent anti-tumor efficacy and biosecurity were observed in the drug-loaded HMNs group in the pharmacodynamic evaluation. In summary, the efficient, convenient, and low-cost fabrication method based on infrared irradiation offers the possibility of mass production of drug-loaded HMNs, showing potential for industrial manufacturing development.

Nanosuspension-Loaded Dissolving Microneedle Patches for Enhanced Transdermal Delivery of a Highly Lipophilic Cannabidiol.

Purpose: Transdermal Drug Delivery System (TDDS) offers a promising alternative for delivering poorly soluble drugs, challenged by the stratum corneum's barrier effect, which restricts the pool of drug candidates suitable for TDDS. This study aims to establish a delivery platform specifically for highly lipophilic drugs requiring high doses (log P > 5, dose > 10 mg/kg/d), to improve their intradermal delivery and enhance solubility. Methods: Cannabidiol (CBD, log P = 5.91) served as the model drug. A CBD nanosuspension (CBD-NS) was prepared using a bottom-up method. The particle size, polydispersity index (PDI), zeta potential, and concentration of the CBD-NS were characterized. Subsequently, CBD-NS was incorporated into dissolving microneedles (DMNs) through a one-step manufacturing process. The intradermal dissolution abilities, physicochemical properties, mechanical strength, insertion depth, and release behavior of the DMNs were evaluated. Sprague-Dawley (SD) rats were utilized to assess the efficacy of the DMN patch in treating knee synovitis and to analyze its skin permeation kinetics and pharmacokinetic performance. Results: The CBD-NS, stabilized with Tween 80, exhibited a particle size of 166.83 ± 3.33 nm, a PDI of 0.21 ± 0.07, and a concentration of 46.11 ± 0.52 mg/mL. The DMN loaded with CBD-NS demonstrated favorable intradermal dissolution and mechanical properties. It effectively increased the delivery of CBD into the skin, extended the action's duration in vivo, and enhanced bioavailability. CBD-NS DMN exhibited superior therapeutic efficacy and safety in a rat model of knee synovitis, significantly inhibiting TNF-α and IL-1ß compared with the methotrexate subcutaneous injection method. Conclusion: NS technology effectively enhances the solubility of the poorly soluble drug CBD, while DMN facilitates penetration, extends the duration of action in vivo, and improves bioavailability. Furthermore, CBD has shown promising therapeutic outcomes in treating knee synovitis. This innovative drug delivery system is expected to offer a more efficient solution for the administration of highly lipophilic drugs akin to CBD, thereby facilitating high-dose administration.