Wearable dual-drug controlled release patch for psoriasis treatment

Wearable drug delivery systems (DDS) have made significant advancements in the field of precision medicine, offering precise regulation of drug dosage, location, and timing. The performance qualities that wearable DDS has always strived for are simplicity, efficiency, and intelligence. This paper proposes a wearable dual-drug synergistic release patch. The patch is powered by a built-in magnesium battery and utilizes a hydrogel containing viologen-based hyperbranched polyamidoamine as both a cathode material and an integrated drug reservoir. This design allows for the simultaneous release of both dexamethasone and tannic acid, overcoming the limitations of monotherapy and ensuring effective synergy for on-demand therapy. In a mouse model with praziquimod-induced psoriasis, the patch demonstrated therapeutic efficacy at a low voltage. The inflammatory skin returned to normal after 5 days with the on-demand release of dual drugs. This work provides a promising treatment option considering its straightforward construction and the therapeutic advantages of dual-drug synergy.

Bifunctional Potential Structure Design Breaks Electrolyte Limitations of Zinc Ion Battery

Aqueous zinc-ion batteries (ZIBs) are safe and economical for grid applications. However, current ZIBs have limitations in terms of inferior capacity and low output voltage, which are hampered by the electrolyte applicability of the Zn2+ hosts. In this study, we propose a novel organic cathode design strategy with a bifunctional potential region. This polymeric Zn2+ host combines the conjugated polyaniline backbone to tune the molecular surface pH and [Fe(CN)6]3-/4- redox couple for high output voltage and capacity. The polyaniline doped with ferricyanide (PAF) electrode exhibits two forms of charge storage in ZIBs: proton-assisted Zn2+ doping below 1.2 V (mechanism I), and [Fe(CN)6]3-/4- redox pair above 1.8 V (mechanism II). Density functional theory calculations and in situ pH experiments demonstrated that the H+ doping process of mechanism I forms a localized pH regulation on the molecular chain surface, providing a favorable reaction environment for mechanism II. The Zn-polymer battery delivered an outstanding discharge capacity (405.2 mAh g-1) and high output voltage (1.8 V) in the Zn(CF3SO3)2 electrolyte. This study provides a new route for enhancing the structural stability of electrodes and overcoming the electrolyte limitations of ferricyanide in weakly acidic electrolytes.

A Multicentric, Retrospective, Real-world Study on Immune-related Adverse Events in Patients with Advanced Non-small Cell Lung Cancers Treated with Pembrolizumab Monotherapy

AIMS

We present 7 years of clinical experience with single-agent pembrolizumab immune checkpoint inhibitor immunotherapy in non-small cell lung cancers (NSCLC) from four UK cancer centres.

MATERIALS AND METHODS

This multi-institutional retrospective cohort study included 226 metastatic NSCLC patients. Outcomes were number and severity of immune-related adverse events (irAEs), median progression-free survival (mPFS) and median overall survival (mOS).

RESULTS

Within our cohort, 119/226 (53%) patients developed irAEs. Of these, 54/119 (45%) experienced irAEs affecting two or more organ systems. The most common irAEs were diarrhoea and rash. The development of an irAE was associated with better mOS (20.7 versus 8.0 months; P < 0.001) and mPFS (12.0 versus 3.9 months; P < 0.001). The development of grade 3/4 toxicities was associated with worse outcomes compared with the development of grade 1/2 toxicities (mOS 6.1 months versus 25.2 months, P < 0.01; mPFS 5.6 months versus 19.3 months, P = 0.01, respectively). Females had a higher proportion of reported grade 3/4 toxicities (13/44 [29.5%] versus 10/74 [13.5%], P = 0.03). Using a multiple Cox regression model, the presence of irAEs was associated with a better overall survival (hazard ratio = 0.42, 95% confidence interval 0.29-0.61; P < 0.01) and better PFS (hazard ratio 0.38, 95% confidence interval 0.27-0.53; P < 0.001).

CONCLUSION

In this multicentre retrospective cohort study, the development of at least one irAE was associated with significantly longer mPFS and mOS; however, more severe grade 3 and 4 irAEs were associated with worse outcomes. Delayed-onset irAEs, after the 3-month timepoint, were associated with better clinical outcomes.

Conductive Viologen Hydrogel Based on Hyperbranched Polyamidoamine for Multiple Stimulus-Responsive Drug Delivery

The emergence of precision medicine and personalized pharmacotherapy has led to the development of advanced drug delivery systems that can respond to multiple stimuli. Conductive hydrogels have excellent electrical signal responsiveness and drug storage capabilities; however, current conductive hydrogels suffer from poor mechanical properties, low ionic conductivity, and high voltage. Herein, a covalently crosslinked viologen hydrogel was prepared using electroactive hyperbranched polyamidoamine (EHP) as the crosslinking center in a polymeric network. Attributed to its unique molecular architecture, this hydrogel exhibits improved mechanical properties (high tensile strength and desirable stretchability up to 1280%). Approvable ionic conductivity, biocompatibility, antibacterial properties, and wearable strain-sensing performance were also disclosed, ascribed to the participation of versatile viologen groups in the hydrogel structure. This hydrogel exhibited high efficiency in drug release (81.6%) at a lower voltage of -1.2 V. Moreover, fascinating pH-stimulus drug release behavior was also demonstrated in both acidic and alkalescent environments owing to the dramatic conformational transition of EHP. This work provides a new design strategy for conductive hydrogels for multiple stimulus-responsive drug delivery systems.

A Piezoelectric-Driven Electrochromic/Electrofluorochromic Dual-Modal Display Device

Electrochromic (EC) reflective displays offer great advantages in delivering information and providing visual data, but are limited in dark environments. Reflective/emissive dual-modal displays capable of electrochemically-induced color and fluorescence change simultaneously are highly desirable, especially possessing rapid response speed as well as long-term durability. Herein, an electroactive fluorescent ionic liquid based on triphenylamine and imidazole (EFIL-TPA) has been synthesized for reflective/emissive dual-modal display. The resultant device exhibits outstanding electrochromic/electrofluorochromic (EC/EFC) performance with low driving voltage (below 1.0 V), fast switching speed (0.57-1.8 s), and remarkable cycling durability (91% retention for 10 000 cycles). A piezoelectric nanogenerator (PENG) driven EC/EFC integrated system is fabricated to harvest energy from human motion and visually drive the color/fluorescence change for human motion indication in both bright and dark environments. This innovative EC/EFC dual-modal display device based on EFIL-TPA supports a huge space for the development of self-powered human motion visualized indication in all-light conditions.

Application and Development of Silicon Anode Binders for Lithium-Ion Batteries

The use of silicon (Si) as a lithium-ion battery's (LIBs) anode active material has been a popular subject of research, due to its high theoretical specific capacity (4200 mAh g^-1). However, the volume of Si undergoes a huge expansion (300%) during the charging and discharging process of the battery, resulting in the destruction of the anode's structure and the rapid decay of the battery's energy density, which limits the practical application of Si as the anode active material. Lithium-ion batteries' capacity, lifespan, and safety can be increased through the efficient mitigation of Si volume expansion and the maintenance of the stability of the electrode's structure with the employment of polymer binders. The main degradation mechanism of Si-based anodes and the methods that have been reported to effectively solve the Si volume expansion problem firstly are introduced. Then, the review demonstrates the representative research work on the design and development of new Si-based anode binders to improve the cycling stability of Si-based anode structure from the perspective of binders, and finally concludes by summarizing and outlining the progress of this research direction.

A biocompatible and fully erodible conducting polymer enables implanted rechargeable Zn batteries

Implanted rechargeable batteries that can provide energy over a sufficient lifetime and ultimately degrade into non-toxic byproducts are highly desirable. However, their advancement is significantly impeded by the limited toolbox of electrode materials with a known biodegradation profile and high cycling stability. Here we report biocompatible, erodible poly(3,4-ethylenedioxythiophene) (PEDOT) grafted with hydrolyzable carboxylic acid pendants. This molecular arrangement combines the pseudocapacitive charge storage from the conjugated backbones and dissolution via hydrolyzable side chains. It demonstrates complete erosion under aqueous conditions in a pH-dependent manner with a predetermined lifetime. The compact rechargeable Zn battery with a gel electrolyte offers a specific capacity of 31.8 mA h g^-1 (57% of theoretical capacity) and outstanding cycling stability (78% capacity retention over 4000 cycles at 0.5 A g^-1). Subcutaneous implantation of this Zn battery into Sprague-Dawley (SD) rats demonstrates complete biodegradation in vivo and biocompatibility. This molecular engineering strategy presents a viable avenue for developing implantable conducting polymers with a predetermined degradation profile and high energy storage capability.

An integrated Mg battery-powered iontophoresis patch for efficient and controllable transdermal drug delivery

Wearable transdermal iontophoresis eliminating the need for external power sources offers advantages for patient-comfort when deploying epidermal diseases treatments. However, current self-powered iontophoresis based on energy harvesters is limited to support efficient therapeutic administration over the long-term operation, owing to the low and inconsistent energy supply. Here we propose a simplified wearable iontophoresis patch with a built-in Mg battery for efficient and controllable transdermal delivery. This system decreases the system complexity and form factors by using viologen-based hydrogels as an integrated drug reservoir and cathode material, eliminating the conventional interface impedance between the electrode and drug reservoir. The redox-active polyelectrolyte hydrogel offers a high energy density of 3.57 mWh cm^-2, and an optimal bioelectronic interface with ultra-soft nature and low tissue-interface impedance. The delivery dosage can be readily manipulated by tuning the viologen hydrogel and the iontophoresis stimulation mode. This iontophoresis patch demonstrates an effective treatment of an imiquimod-induced psoriasis mouse. Considering the advantages of being a reliable and efficient energy supply, simplified configuration, and optimal electrical skin-device interface, this battery-powered iontophoresis may provide a new non-invasive treatment for chronic epidermal diseases.

Preparation and Electrochromic Properties of Benzodithiophene-Isoindigo Conjugated Polymers with Oligoethylene Glycol Side Chains

Functional polymers featuring good processability in non-halogenated, benzene-free green solvents are highly desired due to health and environmental concerns. Herein, a series of novel D-A type conjugated polymers, PBDT-IIDs, are designed and successfully prepared by "green" functionalization of the polymers with highly hydrophilic, highly polar, highly flexible, and biocompatible oligoethylene glycol (OEG) side chains in order to improve the processability. These series polymers are named PBDT-IID2, PBDT-IID3, and PBDT-IID4, respectively, according to the number of oxygen atoms in the side chain. After confirmation by structural characterization, the basic properties of PBDT-IIDs are also investigated. With the increase in the OEG side chain length, the polymer PBDT-IID4 not only has good solubility in the halogen solvent chlorobenzene, but also exhibits excellent solubility in the green halogen-free solvent methyltetrahydrofuran (Me-THF). As a result, the green solvent Me-THF can also be applied to prepare PBDT-IIDs' electrochromic active layers, except for chlorobenzene and toluene. The electrochromism of PBDT IIDs under both positive and negative voltages has a practical application potential. The several controllable switches between dark green and khaki (0-0.6 V) are expected to show great potential in the field of military camouflage. Furthermore, according to the principle of red, green, and blue (RGB) mixing, light blue-green in the reduced state (-1.6 V) can be used in the preparation of complementary ECDs to provide one of the three primary colors (green).

Interface Reversible Electric Field Regulated by Amphoteric Charged Protein-Based Coating Toward High-Rate and Robust Zn Anode

Metallic interface engineering is a promising strategy to stabilize Zn anode via promoting Zn²⁺ uniform deposition. However, strong interactions between the coating and Zn²⁺ and sluggish transport of Zn²⁺ lead to high anodic polarization. Here, we present a bio-inspired silk fibroin (SF) coating with amphoteric charges to construct an interface reversible electric field, which manipulates the transfer kinetics of Zn²⁺ and reduces anodic polarization. The alternating positively and negatively charged surface as a build-in driving force can expedite and homogenize Zn²⁺ flux via the interplay between the charged coating and adsorbed ions, endowing the Zn-SF anode with low polarization voltage and stable plating/stripping. Experimental analyses with theoretical calculations suggest that SF can facilitate the desolvation of [Zn(H₂O)₆]²⁺ and provide nucleation sites for uniform deposition. Consequently, the Zn-SF anode delivers a high-rate performance with low voltage polarization (83 mV at 20 mA cm^-2) and excellent stability (1500 h at 1 mA cm^-2; 500 h at 10 mA cm^-2), realizing exceptional cumulative capacity of 2.5 Ah cm^-2. The full cell coupled with Zn_xV₂O₅·nH₂O (ZnVO) cathode achieves specific energy of ~ 270.5/150.6 Wh kg^-1 (at 0.5/10 A g^-1) with ~ 99.8% Coulombic efficiency and retains ~ 80.3% (at 5.0 A g^-1) after 3000 cycles.

Analgesic dorsal root ganglion field stimulation blocks both afferent and efferent spontaneous activity in sensory neurons of rats with monosodium iodoacetate-induced osteoarthritis

OBJECTIVES

Chronic joint pain is common in patients with osteoarthritis (OA). Non-steroidal anti-inflammatory drugs and opioids are used to relieve OA pain, but they are often inadequately effective. Dorsal root ganglion field stimulation (GFS) is a clinically used neuromodulation approach, although it is not commonly employed for patients with OA pain. GFS showed analgesic effectiveness in our previous study using the monosodium iodoacetate (MIA) - induced OA rat pain model. This study was to evaluate the mechanism of GFS analgesia in this model.

METHODS

After osteoarthritis was induced by intra-articular injection of MIA, pain behavioral tests were performed. Effects of GFS on the spontaneous activity (SA) were tested with in vivo single-unit recordings from teased fiber saphenous nerve, sural nerve, and dorsal root.

RESULTS

Two weeks after intra-articular MIA injection, rats developed pain-like behaviors. In vivo single unit recordings from bundles teased from the saphenous nerve and third lumbar (L3) dorsal root of MIA-OA rats showed a higher incidence of SA than those from saline-injected control rats. GFS at the L3 level blocked L3 dorsal root SA. MIA-OA reduced the punctate mechanical force threshold for inducing AP firing in bundles teased from the L4 dorsal root, which reversed to normal with GFS. After MIA-OA, there was increased retrograde SA (dorsal root reflex), which can be blocked by GFS.

CONCLUSIONS

These results indicate that GFS produces analgesia in MIA-OA rats at least in part by producing blockade of afferent inputs, possibly also by blocking efferent activity from the dorsal horn.

Bioinspired Catechol-Grafting PEDOT Cathode for an All-Polymer Aqueous Proton Battery with High Voltage and Outstanding Rate Capacity

Aqueous all-polymer proton batteries (APPBs) consisting of redox-active polymer electrodes are considered safe and clean renewable energy storage sources. However, there remain formidable challenges for APPBs to withstand a high current rate while maximizing high cell output voltage within a narrow electrochemical window of aqueous electrolytes. Here, a capacitive-type polymer cathode material is designed by grafting poly(3,4-ethylenedioxythiophene) (PEDOT) with bioinspired redox-active catechol pendants, which delivers high redox potential (0.60 V vs Ag/AgCl) and remarkable rate capability. The pseudocapacitive-dominated proton storage mechanism illustrated by the density functional theory (DFT) calculation and electrochemical kinetics analysis is favorable for delivering fast charge/discharge rates. Coupled with a diffusion-type anthraquinone-based polymer anode, the APPB offers a high cell voltage of 0.72 V, outstanding rate capability (64.8% capacity retention from 0.5 to 25 A g-1 ), and cycling stability (80% capacity retention over 1000 cycles at 2 A g-1 ), which is superior to the state-of-the-art all-organic proton batteries. This strategy and insight provided by DFT and ex situ characterizations offer a new perspective on the delicate design of polymer electrode patterns for high-performance APPBs.

Patient deprivation and perceived scan burden negatively impact the quality of whole-body MRI

AIM

To evaluate the association between the image quality of cancer staging whole-body magnetic resonance imaging (WB-MRI) and patient demographics, distress, and perceived scan burden.

MATERIALS AND METHODS

A sample of patients recruited prospectively to multicentre trials comparing WB-MRI with standard scans for staging lung and colorectal cancer were invited to complete two questionnaires. The baseline questionnaire, administered at recruitment, collated data on demographics, distress and co-morbidity. The follow-up questionnaire, completed after staging investigations, measured perceived WB-MRI scan burden (scored 1 low to 7 high). WB-MRI anatomical coverage, and technical quality was graded by a radiographic technician and grading combined to categorise the scan as "optimal", "sub-optimal" or "degraded". A radiologist categorised 30 scans to test interobserver agreement. Data were analysed using the chi-square, Fisher's exact, t-tests, and multinomial regression.

RESULTS

One hundred and fourteen patients were included in the study (53 lung, 61 colorectal; average age 65.3 years, SD=11.8; 66 men [57.9%]). Overall, 45.6% (n=52), scans were classified as "optimal" quality, 39.5% (n=45) "sub-optimal", and 14.9% (n=17) as "degraded". In adjusted analyses, greater deprivation level and higher patient-reported scan burden were both associated with a higher likelihood of having a sub-optimal versus an optimal scan (odds ratio [OR]: 4.465, 95% confidence interval [CI]: 1.454 to 13.709, p=0.009; OR: 1.987, CI: 1.153 to 3.425, p=0.013, respectively). None of the variables predicted the likelihood of having a degraded scan.

CONCLUSIONS

Deprivation and patients' perceived experience of the WB-MRI are related to image quality. Tailored protocols and individualised patient management before and during WB-MRI may improve image quality.

Thermionic microwave gun for terahertz and synchrotron light sources

Conventional thermionic microwave and radio frequency (RF) guns can offer high average beam current, which is important for synchrotron light and terahertz (THz) radiation source facilities, as well as for industrial applications. For example, the Advanced Photon Source at Argonne National Laboratory is a national synchrotron-radiation light source research facility that utilizes thermionic RF guns. However, these existing thermionic guns are bulky, difficult to handle and install, easily detuned, very sensitive to thermal expansion, and due for a major upgrade and replacement. In this paper, we present the design of a new, more stable, and reliable gun with optimized electromagnetic performance, improved thermal engineering, and a more robust cathode mounting technique, which is a critical step to improve the performance of existing and future light sources, industrial accelerators, and electron beam-driven THz sources. We will also present a fabricated gun prototype and show results of high-power and beam tests.

Oligoaniline-functionalized polysiloxane/Prussian blue composite towards bifunctional electrochromic supercapacitors

We report the preparation of a novel oligoaniline-functionalized polysiloxane/Prussian blue composite, which exhibits improved electrochromic properties and approving supercapacitor performance featuring charge storage indicating functionalization.

Adjuvant bevacizumab for melanoma patients at high risk of recurrence: survival analysis of the AVAST-M trial

Background

Bevacizumab is a recombinant humanised monoclonal antibody to vascular endothelial growth factor shown to improve survival in advanced solid cancers. We evaluated the role of adjuvant bevacizumab in melanoma patients at high risk of recurrence.

Patients and methods

Patients with resected AJCC stage IIB, IIC and III cutaneous melanoma were randomised to receive either adjuvant bevacizumab (7.5 mg/kg i.v. 3 weekly for 1 year) or standard observation. The primary end point was detection of an 8% difference in 5-year overall survival (OS) rate; secondary end points included disease-free interval (DFI) and distant metastasis-free interval (DMFI). Tumour and blood were analysed for prognostic and predictive markers.

Results

Patients (n=1343) recruited between 2007 and 2012 were predominantly stage III (73%), with median age 56 years (range 18–88 years). With 6.4-year median follow-up, 515 (38%) patients had died [254 (38%) bevacizumab; 261 (39%) observation]; 707 (53%) patients had disease recurrence [336 (50%) bevacizumab, 371 (55%) observation]. OS at 5 years was 64% for both groups [hazard ratio (HR) 0.98; 95% confidence interval (CI) 0.82–1.16, P = 0.78). At 5 years, 51% were disease free on bevacizumab versus 45% on observation (HR 0.85; 95% CI 0.74–0.99, P = 0.03), 58% were distant metastasis free on bevacizumab versus 54% on observation (HR 0.91; 95% CI 0.78–1.07, P = 0.25). Forty four percent of 682 melanomas assessed had a BRAF^V600 mutation. In the observation arm, BRAF mutant patients had a trend towards poorer OS compared with BRAF wild-type patients (P = 0.06). BRAF mutation positivity trended towards better OS with bevacizumab (P = 0.21).

Conclusions

Adjuvant bevacizumab after resection of high-risk melanoma improves DFI, but not OS. BRAF mutation status may predict for poorer OS untreated and potential benefit from bevacizumab.

Clinical Trial Information

ISRCTN 81261306; EudraCT Number: 2006-005505-64

Family medicine vocational training and career satisfaction in Hong Kong

BACKGROUND

Postgraduate vocational training in family medicine (FM) is essential for physicians to build capacity and develop quality primary care. Inadequate standards in training and curriculum development can contribute to poor recruitment and retention of doctors in primary care. This study aimed to investigate: 1) the satisfaction level of doctors regarding vocational training in family medicine and associated demographics; and 2) the satisfaction level of doctors regarding their family medicine career and associated factors.

METHOD

This is a cross sectional study of all family medicine physicians across all government-funded primary care clinics (GOPCs). The study questionnaire consisted of items from a standardized and validated physician survey named the Physician Worklife Survey (PWS) (Konrad et al., Med Care, 1999). We selected three scales (7 items) relating to global job satisfaction, global career satisfaction and global specialty (family medicine) satisfaction with additional items on training and demographics. All significant variables in bivariate analyses were further examined using stepwise logistic regression.

RESULTS

Out of 424 eligible family medicine physicians, 368 physicians successfully completed the questionnaire. The response rate was 86.8%. Most participants were male (52.6%), were aged between 35 and 44 years (55.5%), were FM specialists (42.4%), graduated locally (86.2%), and had postgraduate qualifications. Eighty-two percent (82%) of participants were satisfied with their training. Having autonomy and protected time for training were associated with satisfaction with FM training. Satisfaction with family medicine as a career was correlated with physicians' satisfaction with their current job. Doctors who did not enroll in training (p < 0.001) and physicians who were older (p = 0.023) were significantly less satisfied. Stepwise multivariate regression showed that doctors who subjectively believed their training as "broad and in depth' had higher career satisfaction (p < 0.001).

CONCLUSION

Overall, the satisfaction level of physicians on current family medicine training in Hong Kong was high. Having autonomy and protected time for training is associated with higher training satisfaction levels. Perceiving FM training as "broad and in-depth" is associated with higher family medicine career satisfaction.

Synthesis and electrochromic properties of a graphene oxide/silicon dioxide/oligoaniline interpenetrating network composite

We report a graphene oxide/silicon dioxide/oligoaniline interpenetrating network composite film through a crosslinking reaction, which demonstrates good electrochromic performance.

Multiple Stimuli-Responsive Fluorescence Behavior of Novel Polyamic Acid Bearing Oligoaniline, Triphenylamine, and Fluorene Groups

Multiple stimuli-responsive fluorescent materials have gained increasing attention for their fundamental investigation and intelligent applications. In this work, we report design and synthesis of a novel polyamic acid bearing oligoaniline, triphenylamine, and fluorene groups, which served as sensitive units and fluorescence emission unit, respectively. The resulting polymer exhibits multiple stimuli-responsive fluorescence switching behavior triggered by redox species, pH, electrochemical, and pressure stimuli. Every fluorescence switching mechanism upon each stimulus was studied in detail. The interactions and energy transfer between sensitive units and emission unit are largely responsible for this fascinating fluorescent switching behavior. This work provides a deep understanding of the optical switching essence upon these stimuli, opening the way for the development of new fluorescent sensing applications.

In situ determination of mechanical properties for poly(ether ether ketone) film under extreme conditions

The isothermal compressibility and pressure dependence of mechanical moduli of PEEK film under extreme conditions have been examined and determined.

Synthesis and electronic properties of comb-like polyamides bearing different contents of tetraaniline pendant groups

Tunable electronic properties could be accomplished by importing different numbers of tetraaniline pendants into the polymeric scaffolds.

Highly stable electrochromic and electrofluorescent dual-switching polyamide containing bis(diphenylamino)-fluorene moieties

A novel semi-aromatic polyamide with bis(diphenylamino)-fluorene moieties was designed and synthesized, which exhibited highly stable electrochromic/electrofluorescent dual-switching properties.

Electroactive self-doped poly(amic acid) with oligoaniline and sulfonic acid groups: synthesis and electrochemical properties

A novel poly(amic acid) with pendant aniline tetramer and sulfonic acid groups (ESPAA) was synthesized by ternary polymerization and characterized by Fourier-transform infrared spectra, ((1))H NMR and gel permeation chromatography. The polymer showed good thermal stability and excellent solubility in the common organic solvents. The electrochemical properties were investigated carefully on a CHI 660A Electrochemical Workstation. The polymer displayed good electroactivity in acid, neutral and even in alkaline solutions (pH=1-10) due to the self-doping effect between aniline tetramer and sulfonic/carboxylic acid groups. It also exhibited satisfactory electrochromic performance with high contrast value, acceptable coloration efficiency and fast switching time in the range of pH=1-9.