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Two-Dimensional Nanomaterials for Drug Delivery in Regenerative Medicine
Published in Harishkumar Madhyastha, Durgesh Nandini Chauhan, Nanopharmaceuticals in Regenerative Medicine, 2022
Zahra Mohammadpour, Seyed Morteza Naghib
Delivery of the drug to the wound area is also possible through the stimuli-responsiveness of graphene-based nanosheets. In this respect, Altinbasak et al. embedded rGO into poly acrylic acid (PAA) nanofibre (PAA@rGO) and used the resulting NIR stimuli-responsive drug delivery mats in wound dressing (Altinbasak et al. 2018). The platform was activated by irradiation of NIR light as an external stimulus, and antibiotics (ampicillin and cefepime) were released on demand. The mats functioned reproducibly, and they were reusable. The interaction of antibiotics with the surface of rGO was established through non-covalent interactions. The photothermal effect of rGO was responsible for the active drug release without any sign of inflammation or bacterial foci in the superficial skin-damaged infection model. In another study, Liu demonstrated that the electrical stimulus could trigger the release of lidocaine hydrochloride based on the electrical conductivity of rGO (Liu et al. 2012). Passive release of the payload was prevented as the rGO in the rGO–PVA membrane acted as a physical barrier.
Magnetic and Plasmonic Nanoparticles for Brain Drug Delivery
Published in Carla Vitorino, Andreia Jorge, Alberto Pais, Nanoparticles for Brain Drug Delivery, 2021
A further advantage of Au NPs is their ability to absorb light of a certain wavelength and to convert and dissipate it locally as heat through a process known as the photothermal effect [16, 29]. This effect produces a localised temperature increase which can be used to provoke tumour cells death due to a process known as hyperthermia [30–32].
Lasers in Photomedicine
Published in Henry W. Lim, Nicholas A. Soter, Clinical Photomedicine, 2018
Roy G. Geronemus, Robin Ashinoff
Other pigmented lesions have been treated with the argon laser including nevus of Ota, labial lentigines, melasma, and Becker’s nevus (80). The mechanism of pigment destruction in these cases has not been proven to be chromophore-specific and probably represents a nonspecific photothermal effect.
Evaluation of combined treatment with long-pulsed neodymium-doped yttrium aluminum garnet laser and potassium hydroxide for the treatment of recalcitrant wart: a prospective comparative study
Published in Journal of Dermatological Treatment, 2020
Fathia M. Khattab, Shrook A. Khashaba
Pfau et al. reported a case with recalcitrant warts clearance by using long pulsed Nd:YAG 1064 nm laser (12). Regarding the principle of laser therapy, it leads to coagulation (photothermal effect) or blasting (photomechanical effect) of the target tissue depending on the pulse duration and energy density (13). HPV virus has shown a better response to thermal therapy than cryotherapy, especially at 39–44 °C. So, the laser-induced hyperthermia can induce the clearance of HPV affected keratinocytes and the surrounding ones as well as, via apoptosis and immune activation. (14) Lasers can provoke migrational maturation of epidermal Langerhans cells, leading to the immune response. These Langerhans cells can regenerate every two weeks with epidermal turnover every 52–75 days (15). That is why lasers can be repeated every two weeks with the endpoint after 3 months for an optimal response.
Laser ablation and topical drug delivery: a review of recent advances
Published in Expert Opinion on Drug Delivery, 2019
Chien-Yu Hsiao, Shih-Chun Yang, Ahmed Alalaiwe, Jia-You Fang
The term laser is an abbreviation of light amplification by stimulated emission of radiation. Laser is a modality producing an intense beam of coherent monochromatic radiation by photon emission stimulation from excited molecules or atoms. The first laser device was developed in 1955 by Dr. Theodore Maiman at Hughes Research Laboratories [7]. The first experience of employing laser for medicinal practice was the use of a ruby laser in tattoo removal by Dr. Leon Goldman [8]. Over the last few decades, lasers have largely been used in dermatology for treating wrinkling, photoaging, hyperpigmentation, actinic keratosis, and scars. The laser is also useful to treat cancers in the presence of photothermal effect. For instance, the near infrared laser in combination with photothermal agents can be applied to deliver anticancer drugs for tumor inhibition [9–11]. The concept of laser-assisted drug transport is based on the reversible ablation or disruption of skin by irradiation to increase skin absorption of the drugs and allow deeper penetration. The first approval of laser-assisted skin delivery was reported by Jacques et al. in 1987 [12]. In that paper, an excimer laser (193 nm) was used to ablate SC from in vitro human skin. The laser fluence at 70 mJ/cm2 produced a 124-fold enhancement of tritiated water permeation, which is similar to that obtained after SC stripping or epidermal removal by mild heat treatment. Since then, some research groups put their efforts into studying drug absorption enhancement by a variety of laser modalities.
Synergistic photothermal/photodynamic suppression of prostatic carcinoma by targeted biodegradable MnO2 nanosheets
Published in Drug Delivery, 2019
Dewang Zeng, Lei Wang, Lu Tian, Shili Zhao, Xianfeng Zhang, Hongyan Li
Inspired by the strong NIR absorbance of MnO2-PEG-cRGD/Ce6, the photothermal conversion property of the nanosheets was explored. It should be noted that 660 nm laser was employed as the light source to realize PTT and PDT simultaneously upon a single laser irradiation to avoid the time interval in biomedical application. As shown in Figure 2(A,B), the temperature of the MnO2-PEG-cRGD/Ce6 nanoparticles increased sharply under 660 nm NIR irradiation. The temperature of the MnO2-PEG-cRGD/Ce6 solution (100 μg/mL) increased to 64.4 °C after 10 min of laser (1 W/cm2) irradiation, while the temperature of deionized water only increased by 0.7 °C. Meanwhile, both concentration and laser-power-dependent photothermal effect was observed, indicated the heat generation could be neatly tuned. Meanwhile, MnO2-PEG-cRGD/Ce6 showed an excellent yet stable light-to-heat conversion property within five cycles of laser irradiation (Figure 2(C)). On the basis of the data obtained from the time constant of heat transfer and the maximum steady-state temperature (Figure 2(D) and Supplementary Figure S5), the photothermal conversion efficiency (η) of MnO2-PEG-cRGD/Ce6 was assessed to be 37.2%, which is higher than that of MnO2-PEG-cRGD (21.4%) as well as higher than some literature reported 2 D PTT agents (Yang et al., 2017b). The enhanced photothermal conversion efficiency confirmed the excellent photothermal synergistic effect of MnO2-PEG-cRGD and Ce6, which provides a potential for photothermal therapy.