808-nm Laser Irradiation Research Articles

Photo-thermal Decomposition of HNS Surface by 532nm Laser Irradiation: Spectral and Quantitative Analysis using In-Situ XPS- Quadrupole MS Technique

Photo-thermal Decomposition of HNS Surface by 532nm Laser Irradiation: Spectral and Quantitative Analysis using In-Situ XPS- Quadrupole MS Technique

Nanozyme-like single-atom catalyst combined with artesunate achieves photothermal-enhanced nanocatalytic therapy in the near-infrared biowindow.

Selectively generating active free radical (AFR) in tumor microenvironment (TME) can promote irreversible oxidation of biomolecules and damage tumor cells, resulting in effective tumor inhibition. However, therapeutic efficacy of AFR-based tumor suppression approaches is often limited by insufficient amount of H2O2 or O2 within TME. To overcome this obstacle, we design a pH/photothermal dual responsive nanosystem (PFeSA@AS) for combined photothermal and nanocatalytic therapy in the near-infrared biowindow. Here the Fe single-atom dispersed N, S-doped carbon nanosheets (FeSA) nanozyme is dispersed by phospholipid-polyethylene glycol-amine (DSPE-PEG-NH2), and further loads artesunate (AS) via an amide reaction. Upon 808-nm laser irradiation in TME, the AS is released and further be catalyzed by the FeSA nanozyme to produce cytotoxic C-centered AFRs, and further be accelerated due to the photothermal conversion performance of FeSA (23.35%). The nanocatalytic process of FeSA nanozyme is realized by density functional theory (DFT). The tumor inhibition rates of a CT26 xenograft model is 92% through a photothermal-enhanced nanocatalytic synergistic therapy, and negligible systematic toxicity is observed. This work offers a potential paradigm of multifunctional single atomic catalysts (SACs) for enhancing tumor nanocatalytic therapy. STATEMENT OF SIGNIFICANCE: We designed a pH/photothermal dual responsive nanosystem (PFeSA@AS) for nanocatalytic therapy: (1) the nanosystem responsively releases AS under 808-nm laser irradiation in TME; (2) FeSA in the nanosystem can act as heme mimetic to convert AS into high cytotoxic C-centered free radicals for nanocatalytic therapy; (3) the photothermal conversion performance of FeSA further enhances the catalytic process to yield abundant AFR. Both in vitro and in vivo results demonstrate that this nanosystem can efficiently inhibit tumor growth through a photothermal-enhanced nanocatalytic synergistic therapy.

Synergistic effects of concurrent photodynamic therapy with indocyanine green and chemotherapy in hepatocellular carcinoma cell lines and mouse models.

Photodynamic therapy (PDT) using an 808nm laser irradiation with indocyanine green (ICG) has shown tumoricidal effects in a hepatocellular (HCC) orthotopic xenograft model. Recently, combining PDT with concurrent chemotherapy has shown synergistic outcomes and a better therapeutic effect for cancer treatment. In the present study, we utilized a combination of chemotherapy drugs and PDT using ICG in vitro and in vivo in a patient-derived orthotopic xenograft (PDoX) model. We independently performed PDT and chemotherapy with sorafenib or doxorubicin in the Huh-7 and Hep3b cell lines by increasing the sorafenib or doxorubicin concentration and increasing the total energy of 808nm light. Subsequently, we combined the two treatments to confirm the effects on cell viability. The combination index (CI) was evaluated in vitro, and thereafter, in the HCC PDoX mouse model, 808nm laser irradiation with intravenously injected ICG and chemotherapy using doxorubicin were performed for twelve days. The viability of the Huh-7 and Hep3B cell lines decreased rapidly as the concentration of sorafenib or doxorubicin increased and as the total energy of 808nm light increased. The cell viability of the Huh-7 and Hep3b cell lines with combined PDT and chemotherapy was less than that with PDT or chemotherapy alone. The CI was <1 in the sorafenib- or doxorubicin-treated Huh-7 and Hep3b cell lines. In the HCC PDoX mouse model, tumor size was markedly decreased, and complete remission achieved compared to that of the single chemotherapy or PDT and control groups. The synergistic effect of concurrent PDT and chemotherapy in the HCC cell line and PDoX model was confirmed with no definite adverse effect. Concurrent PDT and chemotherapy could be applied in further preclinical studies.

Dendritic Plasmonic CuPt Alloys for Closed-Loop Multimode Cancer Therapy with Remarkably Enhanced Efficacy.

The outcome of laser-triggered plasmons-induced phototherapy, including photodynamic therapy (PDT) and photothermal therapy (PTT), is significantly limited by the hypoxic tumor microenvironment and the upregulation of heat shock proteins (HSPs) in response to heat stress. Mitochondria, the biological battery of cells, can serve as an important breakthrough to overcome these obstacles. Herein, dendritic triangular pyramidal plasmonic CuPt alloys loaded with heat-sensitive NO donor N, N'-di-sec-butyl-N, N'-dinitroso-1,4-phenylenediamine (BNN) is developed. Under 808nm laser irradiation, plasmonic CuPt can generate superoxide anion free radicals (·O2 - ) and heat simultaneously. The heat generated can then trigger the release of NO gas, which not only enables gas therapy but also damages the mitochondrial respiratory chain. Impaired mitochondrial respiration leads to reduced oxygen consumption and insufficient intracellular ATP supply, which effectively alleviates tumor hypoxia and undermines the synthesis of HSPs, in turn boosting plasmonic CuPt-based PDT and mild PTT. Additionally, the generated NO and ·O2 - can react to form more cytotoxic peroxynitrite (ONOO- ). This work describes aplasmonic CuPt@BNN (CPB) triggered closed-loop NO gas, free radicals, and mild photothermal therapy strategy that is highly effective at reciprocally promoting antitumor outcomes.

Indocyanine green as a near-infrared theranostic agent for ferroptosis and apoptosis-based, photothermal, and photodynamic cancer therapy.

Ferroptosis is a recently discovered programmed cell death pathway initiated by reactive oxygen species (ROS). Cancer cells can escape ferroptosis, and strategies to promote cancer treatment are crucial. Indocyanine green (ICG) is a near-infrared (NIR) fluorescent molecule used in the imaging of residual tumor removal during surgery. Growing attention has been paid to the anticancer potential of ICG-NIR irradiation by inducing ROS production and theranostic effects. Organic anion transmembrane polypeptide (OATP) 1B3 is responsible for ICG metabolism. Additionally, the overexpression of OATP1B3 has been reported in several cancers. However, whether ICG combined with NIR exposure can cause ferroptosis remains unknown and the concept of treating OATP1B3-expressing cells with ICG-NIR irradiation has not been validated. We then used ICG as a theranostic molecule and an OATP1B3-transfected fibrosarcoma cell line, HT-1080 (HT-1080-OATP1B3), as a cell model. The HT-1080-OATP1B3 cell could promote the uptake of ICG into the cytoplasm. We observed that the HT-1080-OATP1B3 cells treated with ICG and exposed to 808-nm laser irradiation underwent apoptosis, as indicated by a reduction in mitochondrial membrane potential, and upregulation of cleaved Caspase-3 and Bax but downregulation of Bcl-2 expression. Moreover, lipid ROS production and consequent ferroptosis and hyperthermic effect were noted after ICG and laser administration. Finally, in vivo study findings also revealed that ICG with 808-nm laser irradiation has a significant effect on cancer suppression. ICG is a theranostic molecule that exerts synchronous apoptosis, ferroptosis, and hyperthermia effects and thus can be used in cancer treatment. Our findings may facilitate the development of treatment modalities for chemo-resistant cancers.

Covalent organic polymer induces apoptosis of liver cancer cells via photodynamic and photothermal effects.

Purp@COP is a covalent organic polymer (COP) with robust tailoring heteroatom incorporation, plentiful pore structure, and multiple functions similar to the metal-organic framework (MOF). Hepatocellular carcinoma cell line HepG2 was cultured with Purp@COP for 24 h and treated with near-infrared 808-nm laser 1 W/cm2 for 10 min. Cell Counting Kit-8 (CCK-8) assay, colony formation assay, live-dead cell fluorescence staining, and Annexin V/propidium iodide (PI) staining flow cytometry were performed to detect the viability, proliferation, and apoptosis of the HepG2 cells. The supramolecular material Purp@COP exhibited significant photothermal performance under near-infrared 808-nm laser irradiation in vitro. With the treatment of Purp@COP and near-infrared 808-nm laser irradiation on HepG2 cells, cell viability and colony formation capacity were decreased, and the number and proportion of apoptotic cells were increased. The supramolecular material Purp@COP has both photothermal and photodynamic effects and can significantly induce cancer cell death and inhibit the proliferation of cancer cells in vitro.

Vacancy-Modulated of CuS for Highly Antibacterial Efficiency via Photothermal/Photodynamic Synergetic Therapy.

Cu-based nanomaterials have been developed to alleviate the problem of antibiotic resistance due to their superior properties and good biocompatibility. Defects in nanomaterials have a major role in improving photocatalytic performance. Herein, two CuS nanospheres with predominant VCuSCu and VCuSS vacancy (abbreviated as CuS and CuS-T150, respectively) characterized by positron annihilation spectra are synthesized. The combination of experimental and theoretical calculation results demonstrates that CuS-T150 exhibits excellent antibacterial, achieving bactericidal rates of 99.9% against to Escherichia coli (E. coli) under 808nm laser irradiation. Compared with CuS, the superior antimicrobial activity of CuS-T150 is mainly attributed to its stronger ability to adsorb oxygen molecules, more easily bind with surface of E. coli, and higher photothermal conversion efficiency (PTCE). This work provides a deeper understanding of nanomaterials with vacancy modulated the antibacterial efficiency by synergistic effect of photodynamic and photothermal therapy.

Photothermal biosensor for HPV16 based on strand-displacement amplification and gold nanoparticles using a thermometer as readout.

Gold nanoparticles (AuNPs) in aggregated state have a strong near infrared region (NIR) absorption and the causes a much stronger photothermal effect than that of the dispersed AuNPs. Strand-displacement amplification (SDA) can produce large amount of single-stranded DNA (ssDNA), which in turn effectively prevent AuNPs from aggregation. In this study, these characteristics had been applied to design a photothermal biosensor for human papilloma virus (HPV and HPV16 were chosen as model target) detection. In the absence of HPV16, AuNPs was in the aggregated state and large temperature rise can be detected after the irradiation by 808nm laser. The presence of HPV16 triggers the SDA reaction with the help of Bst DNA polymerase and Nt.BstNBI nicking endonuclease resulting in the production of large amounts of ssDNA; this protects unmodified AuNPs from salt-induced aggregation. Therefore, AuNPs was in a dispersed state and the temperature change was not significant after the irradiation of 808nm laser. The difference of the temperature changing can be applied for the quantitative detection of HPV16 using a thermometer as readout. The linear response range is 1.0 fM ~ 50pM with a detection limit of 0.3 fM. The proposed method has been applied to detect HPV16 in clinical cervical sample and is competent for clinical analysis.

The single-atom iron nanozyme mimicking peroxidase remodels energy metabolism and tumor immune landscape for synergistic chemodynamic therapy and photothermal therapy of triple-negative breast cancer.

Chemotherapy, as one main strategy to relieve tumor progression, has a weak effect on triple-negative breast cancer (TNBC) chest wall metastasis. The development of near-infrared (NIR) light-responsive nanomaterials for chemodynamic therapy (CDT) and photothermal therapy (PTT) is a promising platform but still challenging in biomedicine. This study reports a peroxidase mimicking nanozyme (Fe-N-C SAzyme) against TNBC by CDT and PTT. Fe-N-C SAzyme generated reactive oxygen species (ROS) by decomposing H2O2 into hydroxyl radicals (•OH) and also induced light-to-heat conversion under the exposure of 808nm laser irradiation. With these biological characteristics, the obtained Fe-N-C SAzymes displayed enhanced cell cytotoxicity and inhibition of cancer cell proliferation both in vitro and in vivo at a low dose of nanoagent and a moderate NIR laser power density. Besides, Fe-N-C nanoagent with its excellent ROS generation brought metabolic reprogramming of elevated glycolysis in tumor cells. In vivo experiments, when combined with PTT, the enhanced antitumor effect was found by the elimination of M-MDSC in tumor microenvironment. Fe-N-C SAzymes can serve as a new synergistic CDT and PTT nanoagent to simultaneously reprogram tumor metabolism and tumor microenvironment. It will provide prospects for chemodynamic/photothermal combined cancer therapy for TNBC chest wall metastasis based on the use of a single nanosystem.

Inactivation of SARS-CoV-2 Spike Protein Pseudotyped Virus Infection Using ACE2-Tethered Gold Nanorods under Near-Infrared Laser Irradiation.

Since the angiotensin-converting enzyme 2 (ACE2) protein is abundant on the surface of respiratory cells in the lungs, it has been confirmed to be the entry-point receptor for the spike glycoprotein of SARS-CoV-2. As such, gold nanorods (AuNRs) functionalized with ACE2 ectodomain (ACE2ED) act not only as decoys for these viruses to keep them from binding with the ACE2-expressing cells but also as agents to ablate infectious virions through heat generated from AuNRs under near-infrared (NIR) laser irradiation. Using plasmid containing the SARS-CoV-2 spike protein gene (with a D614G mutation), spike protein pseudotyped viral particles with a lentiviral core and green fluorescent protein reporter were constructed and used for transfecting ACE2-expressing HEK293T cells. Since these viral particles behave like their coronavirus counterparts, they are the ideal surrogates of native virions for studying viral entry into host cells. Our results showed that, once the surrogate pseudoviruses with spike protein encounter ACE2ED-tethered AuNRs, these virions are entrapped, resulting in decreased viral infection to ACE2-expressing HEK293T cells. Moreover, the effect of photothermolysis created by ACE2ED-tagged AuNRs under 808-nm NIR laser irradiation for 5 min led to viral breakdown. In summary, ACE2ED-tethered AuNRs with dual functions (virus decoy and destruction) could have an intriguing advantage in the treatment of diseases involving rapidly mutating viral species such as SARS-CoV-2.

‘Switch to love, switch to kill—dose and light co-regulate iron single-atom nanozyme to modulate cell fate

Remote control of cells and the regulation of cell events at the molecular level are of great interest to the biomedical field. In addition to mechanical forces and genes, chemical compounds and light play pivotal roles in regulating cell fate, which have boosted the fast growth of biology. Herein, we synthesized light-regulated, atomically dispersed Fe-N4 immobilized on a carbon substrate nanozyme (Fe-N/C single atom catalysts), whose peroxidase- and catalase-like properties can be enhanced by 120% and 135%, respectively, under 808-nm laser irradiation through the photothermal effect of Fe-N/C. Interestingly, a switch to love/switch to kill interaction between Fe-N/C dose and near-infrared (NIR) light co-regulating the Fe-N/C nanozyme to modulate cell fate was discovered. Based on this, we found that under NIR light irradiation, when the dose of Fe-N/C is low, it can scavenge more reactive oxygen species (ROS) and achieve cell protection; when the dose of Fe-N/C is too high, it tended to lead to cell apoptosis. This work not only provides an effective strategy for the regulation of nanozyme activity but also realizes the dual-functional application of nanozyme materials for the treatment of some specific diseases.

Two-dimensional ultrathin Ti3C2 MXene nanosheets coated intraocular lens for synergistic photothermal and NIR-controllable rapamycin releasing therapy against posterior capsule opacification.

Posterior capsule opacification (PCO) is one of the most frequent late-onset complications after cataract surgery. Several kinds of drug-eluting intraocular lenses (IOL) were designed for sustainable drug release to suppress ocular inflammation, the proliferation of lens epithelial cells (LECs) and the development of PCO after cataract surgery. Despite previous advances in this field, the drug-loaded IOLs were limited in ocular toxicity, insufficient drug-loading capacity, and short release time. To prevent PCO and to address these drawbacks, a novel drug-loaded IOL (Rapa@Ti3C2-IOL), prepared from two-dimensional ultrathin Ti3C2 MXene nanosheets and rapamycin (Rapa), was fabricated with a two-step spin coating method in this study. Rapa@Ti3C2 was prepared via electrostatic self-assembly of Ti3C2 and Rapa, with a loading capacity of Rapa at 92%. Ti3C2 was used as a drug delivery reservoir of Rapa. Rapa@Ti3C2-IOL was designed to have the synergistic photothermal and near infrared (NIR)-controllable drug release property. As a result, Rapa@Ti3C2-IOL exhibited the advantages of simple preparation, high light transmittance, excellent photothermal conversion capacity, and NIR-controllable drug release behavior. The Rapa@Ti3C2 coating effectively eliminated the LECs around Rapa@Ti3C2-IOL under a mild 808-nm NIR laser irradiation (1.0 W/cm−2). Moreover, NIR-controllable Rapa release inhibited the migration of LECs and suppressed the inflammatory response after photothermal therapy in vitro. Then, Rapa@Ti3C2-IOL was implanted into chinchilla rabbit eyes, and the effectiveness and biocompatibility to prevent PCO were evaluated for 4 weeks. The Rapa@Ti3C2-IOL implant exhibited excellent PCO prevention ability with the assistance of NIR irradiation and no obvious pathological damage was observed in surrounding healthy tissues. In summary, the present study offers a promising strategy for preventing PCO via ultrathin Ti3C2 MXene nanosheet-based IOLs with synergistic photothermal and NIR-controllable Rapa release properties.

Glycosylated phospholipid-coated upconversion nanoparticles for bioimaging of non-muscle invasive bladder cancers.

Detection of non-muscle invasive bladder cancer (NMIBC) is crucial to facilitate complete tumor resection, thus improving the survival rate as well as reducing the recurrence frequency and treatment expense. Fluorescence imaging cystoscopy is an effective method for the detection of NMIBC. However, its application is limited as the commonly applied fluorescent agents such as dyes and photosensitizers usually lack specific tumor accumulation and are vulnerable to photobleaching. Furthermore, the broad emission band of conventional fluorescent agents limits their imaging and detection efficacy. To overcome these limitations, upconversion nanoparticles (UCNPs) have been selected as the fluorescent agent, due to their resistance to photobleaching, less background auto-fluorescence, and narrow emission bands. In order to achieve active tumor targeting, the UCNPs are coated with a glycosylated phospholipid layer. The glycosylated phospholipid-coated UCNPs exhibited high selective accumulation in cancer cells over normal cells and enhanced the upconversion luminescence (UCL) (at 540nm and 660nm) from bladder cancer cells under 980nm laser irradiation. Glycosylated phospholipid coating that promotes uptake of UCNPs by cancer cells, and UCL emitted from UCNPs under NIR (980nm) laser irradiation for cancer cell imaging.

Utilization of gold nanoparticles for the detection of squamous cell carcinoma of the tongue based on laser-induced fluorescence and diffuse reflectance characteristics: an in vitro study

Squamous cell carcinoma is a very common type of oral cancer that affects the health of people with an unacceptably high mortality rate attributed to the difficulties in detecting the disease at an early stage. Therefore, effective techniques for early diagnosis and effective therapy of oral cancer are necessary. In the present study, we exploit the ability of gold nanoparticles (AuNPs) to undergo coupled surface plasmon resonance when closely spaced to improve diagnosing squamous cell carcinoma of the tongue. The prepared AuNPs are characterized by UV–VIS spectroscopy, dynamic light scattering, Fourier transform infrared spectroscopy, and transmission electron microscopy. The size of the prepared AuNPs is 12 ± 2 nm with narrow size distributions and exhibited high stability with a zeta potential of − 16.5 mV. The light fluorescence of the normal and cancer cells is recorded before and after NP addition using a spectrometer upon excitation by 405-nm laser irradiation. Furthermore, the light reflectance of the examined samples is measured at different laser wavelengths (red to NIR region). The obtained results show that the cancer cells mixed with AuNPs produce a higher fluorescence peak at 489.2 nm than the cancer cells without AuNPs. Moreover, the optical diffuse reflectance analyses reveal that the addition of AuNPs enhances cancer detection especially at the 635-nm irradiation with sensitivity (94%), specificity (87%), and overall accuracy (91%).

Acceptor-donor-acceptor structured phototheranostics for near-infrared II fluorescent and photoacoustic imaging-guided photodynamic and photothermal synergistic therapy

Multi-modal imaging-guided synergistic photodynamic therapy (PDT) and photothermal therapy (PTT) show great benefits in cancer treatment. The phototheranostics with near-infrared (NIR) absorption, high reactive oxygen species (ROS) generation and photothermal conversion efficiency is highly desirable. Here, we designed and synthesized an “acceptor-donor-acceptor” (A-D-A) structured molecule named IDCIC, with strong absorbance in the NIR region. We further prepared IDCIC into water-soluble nanoparticles (NPs) by wrapping with 1,2-distearoylsn-glycero-3-phosphoethanolamine-N-[(polyethylene glycol)-2000]-amine (DSPE-PEG2000-NH2). The obtained IDCIC NPs show an NIR absorption peak at 760 nm and an NIR-II fluorescence spectrum peak at ∼1000 nm with a fluorescent quantum yield of 1.2%, enabling them excellent photoacoustic and NIR-II fluorescent imaging capabilities. Moreover, IDCIC NPs could simultaneously generate singlet oxygen (with a quantum yield of 9.1%), hydroxyl radicals (·OH) and heat (with a photothermal conversion efficiency of 78.9%) under 808-nm laser irradiation. Based on the above-mentioned properties, IDCIC NPs were used for dual-modal imagingguided synergistic photodynamic/photothermal therapy of cancer.

Targeted Multifunctional Nanoplatform for Imaging-Guided Precision Diagnosis and Photothermal/Photodynamic Therapy of Orthotopic Hepatocellular Carcinoma.

BackgroundEffective theranostic of hepatocellular carcinoma (HCC) in an early-stage is imminently demanded to improve its poor prognosis. Combination of the near-infrared (NIR) photoacoustic imaging (PAI) and fluorescence imaging (FLI) can provide high temporospatial resolution, outstanding optical contrast, and deep penetration and thus is promising for accurate and sensitive HCC diagnosis.MethodsA versatile CXCR4-targeted Indocyanine green (ICG)/Platinum (Pt)-doped polydopamine melanin-mimic nanoparticle (designated ICG/Pt@PDA-CXCR4, referred to as IPP-c) is synthesized as an HCC-specific contrast agent for high-resolution precise diagnostic PAI/FLI and optical imaging-guided targeted photothermal therapy (PTT)/photodynamic therapy (PDT) of orthotopic small hepatocellular carcinoma (SHCC).ResultsThe multifunctional targeted nanoparticle yields superior HCC specificity, high imaging contrast in both PAI and FLI, good stability, reliable biocompatibility, effective singlet oxygen generation and superior photothermal conversion efficiency (PCE, 58.7%) upon 808-nm laser irradiation. The targeting ability of IPP-c was validated in in vitro experiments on selectively killing the CXCR4-overexpressing HCC cells. Moreover, we test the efficient dual-modal optical precision diagnosis properties of IPP-c via in vivo experiments on targeted particle accumulation in an early-stage SHCC mouse model (tumor diameter about 1.2 mm). Then, under the guidance of real-time optical imaging, effective and mini-invasive PTT/PDT of orthotopic SHCCs were demonstrated without damaging adjacent liver tissues or other major organs.ConclusionThis study presented a multifunctional CXCR4-targeted nanoparticle to conduct effective and mini-invasive phototherapeutics of orthotopic SHCCs via the real-time quantitative guidance by optical imaging, which provided a new perception for building a versatile targeted nanoplatform for phototheranostics of early-stage HCC.

Photothermal effect of albumin-modified gold nanorods diminished neuroblastoma cancer stem cells dynamic growth by modulating autophagy

Here, we investigated the photothermal effect of gold nanorods (GNRs) on human neuroblastoma CD133+ cancer stem cells (CSCs) via autophagic cell death. GNRs were synthesized using Cetyltrimethylammonium bromide (CTAB), covered with bovine serum albumin (BSA). CD133+ CSCs were enriched from human neuroblastoma using the magnetic-activated cell sorting (MACS) technique. Cells were incubated with GNRs coated with BSA and exposed to 808-nm near-infrared laser irradiation for 8 min to yield low (43 °C), medium (46 °C), and high (49 °C) temperatures. After 24 h, the survival rate and the percent of apoptotic and necrotic CSCs were measured using MTT assay and flow cytometry. The expression of different autophagy-related genes was measured using polymerase chain reaction (PCR) array analysis. Protein levels of P62 and LC3 were detected using an enzyme-linked immunosorbent assay (ELISA). The viability of CSC was reduced in GNR-exposed cells compared to the control group (p < 0.05). At higher temperatures (49 °C), the percent of apoptotic CSCs, but not necrotic cells, increased compared to the lower temperatures. Levels of intracellular LC3 and P62 were reduced and increased respectively when the temperature increased to 49 °C (p < 0.05). These effects were non-significant at low and medium temperatures (43 and 46 °C) related to the control CSCs (p > 0.05). The clonogenic capacity of CSC was also inhibited after photothermal therapy (p < 0.05). Despite these changes, no statistically significant differences were found in terms of CSC colony number at different temperatures regardless of the presence or absence of HCQ. Based on the data, the combination of photothermal therapy with HCQ at 49 °C can significantly abort the CSC clonogenic capacity compared to the control-matched group without HCQ (p < 0.0001). PCR array showed photothermal modulation of CSCs led to alteration of autophagy-related genes and promotion of co-regulator of apoptosis and autophagy signaling pathways. Factors related to autophagic vacuole formation and intracellular transport were significantly induced at a temperature of 49 °C (p < 0.05). We also note the expression of common genes belonging to autophagy and apoptosis signaling pathways at higher temperatures. Data showed tumoricidal effects of laser-irradiated GNRs by the alteration of autophagic response and apoptosis.

Gd2O3/b-TiO2 composite nanoprobes with ultra-high photoconversion efficiency for MR image-guided NIR-II photothermal therapy.

Photothermal therapy (PTT), as an important noninvasive and effective tumor treatment method, has been extensively developed into a powerful cancer therapeutic technique. Nevertheless, the low photothermal conversion efficiency and the limited tissue penetration of typical photothermal therapeutic agents in the first near-infrared (NIR-I) region (700-950nm) are still the major barriers for further clinical application. Here, we proposed an organic/inorganic dual-PTT agent of synergistic property driven by polydopamine-modified black-titanium dioxide (b-TiO2@PDA) with excellent photoconversion efficiency in the second NIR (NIR-II) region (1000-1500nm). More specifically, the b-TiO2 treated with sodium borohydride produced excessive oxygen vacancies resulting in oxygen vacancy band that narrowed the b-TiO2 band gap, and the small band gap led to NIR-II region wavelength (1064nm) absorbance. Furthermore, the combination of defect energy level trapping carrier recombination heat generation and conjugate heat generation mechanism, significantly improved the photothermal performance of the PTT agent based on b-TiO2. The photothermal properties characterization indicated that the proposed dual-PTT agent possesses excellent photothermal performance and ultra-high photoconversion efficiency of 64.9% under 1064nm laser irradiation, which can completely kill esophageal squamous cells. Meanwhile, Gd2O3 nanoparticles, an excellent magnetic resonance imaging (MRI) agent, were introduced into the nanosystem with similar dotted core-shell structure to enable the nanosystem achieve real-time MRI-monitored cancer therapeutic performance. We believe that this integrated nanotherapeutic system can not only solve the application of PTT in the NIR-II region, but also provide certain theoretical guidance for the clinical diagnosis and treatment of esophageal cancer.

Dual-readout immunosensor based on multifunctional MXene probe triggers thesignal amplification for detection of autoimmune hepatitis marker.

A dual-readout immunosensor coupled with electrochemical impedance and temperature signal was successfully proposed to detect autoimmune hepatitis markers (ASGPR). Nb2C MXene with excellent conductivity, abundant surface functional groups, and extraordinary photothermal conversion efficiency, was designed to be a multifunctional biological probe, whose specific binding with antigen enhanced steric hindrance to generate electrochemical impedance signal, and at the same time, it had a strong optical response in the near-infrared band to achieve temperature output. In addition, poly(N-isopropyl acrylamide) (PNIPAM) was a temperature-sensitive polymer, which was adopted as the sensing matrix. When the multifunctional probe was specifically bound to the antigen, under 808-nm laser irradiation, the captured Nb2C MXene achieved photothermal conversion to increase the electrode surface temperature, and the conformation of PNIPAM changed from a free spiral to a spherical shape, further realizing double amplification of theEIS signal. Under the optimized experimental conditions, the impedance values and the temperature changes increased proportionally with the increase of the ASGPR concentration from 10-5 to 1ng/mL, and the detection limit of the immunosensor was 3.3 × 10-6ng/mL. The established dual-readout immunosensor exhibited good selectivity and acceptable stability and provided an effective detection method for autoimmune hepatitis marker detection.

季铵化介孔碳纳米球的合成及其在体内协同光热抗菌治疗

<p indent="0mm">Photothermal antimicrobial therapy (PTT) has more advantages than traditional antimicrobial therapy. Photothermal conversion nanomaterials can convert optical energy into thermal energy for killing bacteria under near-infrared light. Compared with antibiotic therapy, PTT has several advantages, such as broad-spectrum antimicrobial performance, spatiotemporal specificity, minimally invasive, and deep tissue penetration, and does not cause bacterial resistance. Nevertheless, the therapeutic effect of PTT monotherapy is not ideal because it is often accompanied by side effects, such as thermal injury. To overcome this shortcoming, synergistic photothermal therapy has attracted extensive research interests. This study first synthesized mesoporous carbon nanospheres (MCNs) with commendable solar-thermal conversion performance and uniform size. Then, carboxy-rich MCNs (CMCNs) were obtained by heating in a mixed acid solution. Subsequently, polyethyleneimine (PEI) was covalently grafted onto the surface of CMCNs using the 1-ethyl-3-(3-dimethyl aminopropyl)-carbodiimide (EDC) and N-hydroxysuccinimide (NHS) coupling reaction. Finally, quaternized mesoporous carbon nanospheres (CMCN-QAC) was obtained using a quaternization reaction. The morphology and crystalline forms of MCNs were analyzed using scanning electron microscopy and X-ray diffraction. The photothermal conversion performance of CMCNs was evaluated using an infrared thermal imager. It was found that the photothermal conversion performance of CMCNs was related to the material concentration and the 808-nm near-infrared laser irradiation power intensity. Moreover, photothermal stability experiments were conducted, and the results show that the CMCNs has stable photothermal conversion performance and stability. Next, the spread plate method and live/dead staining experiments were conducted to study the synergistic photothermal antibacterial effect of CMCN-QAC<italic> in vitro</italic>. The MBC value of CMCN-QAC was 60-μg/mL under 1.5-W/cm² 808-nm near infrared (NIR) laser for <sc>10 min.</sc> Finally, to investigate the synergistic photothermal therapy of CMCN-QAC <italic>in vivo</italic>, we established a mouse model of wound infection induced by <italic>Escherichia coli</italic>. The <italic>in vitro</italic> and <italic>in vivo</italic> results showed that the CMCN-QAC+NIR group exhibited the best therapeutic effect and high biocompatibility, indicating that CMCN-QAC has great potential to serve as a novel synergistic photothermal antimicrobial nanomaterial to treat bacterial infections.