• Title/Summary/Keyword: Photosensitizer

Search Result 164, Processing Time 0.022 seconds

The Effect of Ginseng Extracts on Photooxidation in Serum Lipid (혈청지질의 광산화 반응에 미치는 인삼추출물의 영향)

  • 백태홍;천현자
    • Journal of Ginseng Research
    • /
    • v.13 no.2
    • /
    • pp.234-238
    • /
    • 1989
  • In the presence of a photosensitizer, rose bengal, phooxidatlon in serum total lipids has been studied and the effects of ginseng water extract and saponins on it have reviewed. In the presence of rose bengal, serum total lipids undergo photooxidation and produce lipid hydroperoxides. On the other hand, ginseng water extract and dial saponins largely inhibit photooxidation and decrease the amount of lipid hydroperoxides in serum total lipids.

  • PDF

Development of Excitation Light Source for Photodynamic Diagnosis of Cancer (광역학적 암진단을 위한 여기 광원장치의 개발)

  • Lim, Hyun-Soo
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.44 no.6
    • /
    • pp.49-56
    • /
    • 2007
  • In this paper, the development of excitation light source is proposed for excitation light of the photodynamic therapy of cancer. Since the selection of the wavelength band of excitation light has an interrelation with fluorescence generation according to the selection of a photosensitizer. This study aims at designing and evaluating light source that can stably generate light with various kinds of wavelengths in order to make possible photodynamic diagnosis using a photosensitizer and diagnosis using auto-fluorescence. The light source device was a Xenon lamp and filter wheel, composed of an optical output control through iris and filters with several wavelength bands. It also makes the inducement of auto-fluorescence possible because it is designed to generate a wavelength band of 380-420nm, 430-480nm, 480-560nm. The transmission part of the light source was developed to enhance the efficiency of light transmission. To evaluate this light source device by KFDA#s technical reference, the characteristics of the light output and wavelength band were found.

Photopodegradation efficiency of visible light cured dental resin composites with novel photosensitizers (가시광선 중합형 복합수지용 광증감제의 분해율 비교)

  • Sun, Gum-Ju
    • Journal of Technologic Dentistry
    • /
    • v.33 no.4
    • /
    • pp.291-297
    • /
    • 2011
  • Purpose: The purpose of this study was to know the availability of three photosensitizers, CQ, PD, DA, as a photosensitizer of dental resin composite. We want to know abortion band around visible light region for the using potential possibility as a photosensitizer for visible light cured dental composite resin. And I studied to know the relative photodecomposition ratio of three photosensitizers with or without photoinitiator, DAEM. Methods: The photodecomposition of three photosensitizers were studied by UV absorption spectroscopy in ethanol and determined by same instrument with irradiation time for relative photodecomposition. In order to study the effect of amine on photodecomposition was added the DAEM in the photosensitizer solution and the relative rate was measured by the same procedure with aove mentioned. Results: The all of three photosensitizers are absorbed around visible light region. The relative rate of decrease in absorbance incereased in the order: CQ < BD < PD. The effect of DAEM on the photodecomposition of the photosensitizers was appeared different results without DAEM. The photodecomposition rate of PD and DA decreased somewhat with the addition of amine, while that of CQ increased. The rtealtive photodecomposition rate increased in the oprder: BD ${\leq}$ CQ < PD with the addition of amine, but the differnce was not significant. Conclusion: PD and DA like CQ gives to the possibility of use as a photosensitizer for visible light cured dental composite resin by absorption around visible light region and photodecomposition in the maximum absorption wavelength. And it is showed that PD and DA are not effective decomposed with amine initiator, DAEM but CQ decomposed with DAEM effectively. This result may be due to a different mechanism operating for the decomposition of photosensitizers in the presence of amine.

A Study on the Measurements of Optical Parameters in Photosensitizer by Light Scattering (농도가 진한 매질에서 광증감제에 의한 광학적 파라미터측정에 관한 연구)

  • Kim, Ki-Jun;Lee, Jou-Joub
    • Journal of the Korean Applied Science and Technology
    • /
    • v.28 no.1
    • /
    • pp.102-108
    • /
    • 2011
  • The study of wave propagation and scattering in biological media has become increasingly important in recent years. The propagation of light within tissues is an important problem that confronts the dosimetry of therapeutic laser delivery and the development of diagnostic spectroscopy. In the clinical application of photodynamic therapy(PDT) and in photobiology, the photon deposition within a tissue determines the spatial distribution of photochemical reactions. Scattered light is measured as a function of the distance (r) between the axis of the incident beam and the detection spot. Consequently, knowledge of the photosensitizer(Chlorophyll-a) function that characterizes a phantom is measured. To obtain the results of scattering coefficients(${\mu}s$) of a turbid material from diffusion described by experimental approach. It was measured the energy fluency of photon radiation at the position of penetration depth. From fluorescence experimental method obtained the analytical expression for the scattered light as the values of $(I/I_o)_{wavelength}$ vs the distance between the center of the incident beam and optical fiber in terms of the condition of "in situ spectroscopy(optically thick)" and real time by fluorometric measurements. The result was compromised with transport of intensities though a random distribution of scatters.

A Study on the Optical Influence by Photosensitizer in Vitro (In Vitro에서 광증감제에 의한 광학적 영향에 관한 연구)

  • Kim, Ki-Jun;Sung, Ki-Chun
    • Journal of the Korean Applied Science and Technology
    • /
    • v.22 no.2
    • /
    • pp.182-190
    • /
    • 2005
  • The propagation of light radiation within tissues is an important problem that confronts the dosimetry of therapeutic laser delivery and the development of diagnostic spectroscopy. In the clinical application of photodynamic therapy(PDT) and in photobiology, the photon deposition within a tissue determines the spatial distribution of photochemical reactions. Scattered light is measured as a function of the distance (r) between the axis of the incident beam and the detection spot. Consequently, knowledge of the photosensitizer(Chlorophyll-a) function that characterizes a phantom is important. To obtain the results of scattering coefficients(${\mu}s$) of a turbid material from diffusion described by experimental approach. It was measured the energy fluency of photon radiation at the position of penetration depth. From fluorescence experimental method obtained the analytical expression for the scattered light as the values of $(I\;/I_o)_{wavelength}$ vs the distance between the center of the incident beam and optical fiber in terms of the condition of "in situ spectroscopy(optically thick)" and real time by fluorometric measurements.

Photodynamic Therapy for Methicillin-resistant Staphylococcus aureus Using Various Photosensitizer

  • Kwon, Pil-Seung;Jo, Yoon-Kyung
    • Biomedical Science Letters
    • /
    • v.15 no.3
    • /
    • pp.233-239
    • /
    • 2009
  • The aim of this study was to evaluate the photodynamic effect of various photosensitizing agents against methicillin-resistant Staphylococcus aureus (MRSA). MRSA was exposed to light from a 632 urn diode laser (15 J/$cm^2$) in the presence of various photosensitizer, such as photofrin, photogem, radachlorine and ALA. In vivo study was performed using ICR mice. Twenty eight mice had a standard wound ($100\;mm^2$) created on the dorsum, and MRSA was inoculated into the wound region. The four groups were classified as follows: (1) the untreated control group (bacteria alone), (2) the bacteria plus light group (15 J/$cm^2$), (3) the bacteria plus photofrin group (kept in the dark), and (4) the photodynamic therapy (PDT) group (bacteria, photofrin, and light). After photofrin (dose 1 mg/kg) injection, the experimental group was irradiated with 632 urn diode laser (15 J/$cm^2$) for 30 minutes after In vitro results of PDT showed the complete killing of MRSA at the photofrin, radachlorine, and photogem However, ALA-PDT was ineffective on MRSA viability. In vivo results showed that photofrin has therapeutic effect on the wound infection. These results demonstrate that selective lethal photosensitization of MRSA can be achieved using phofrin, photogem and radachlorin. Thus, PDT can inactivate MRSA survival.

  • PDF

Photo-Induced Graft Copolymerization of Acrylonitrile onto Chitosan (Chitosan에 대한 아크릴로니트릴의 광개시 그라프트 공중합)

  • Kim, Wan-Young;Kim, Chong-Bae;Yug, Gyeong-Chang;Park, Sun-Ny
    • Applied Chemistry for Engineering
    • /
    • v.3 no.1
    • /
    • pp.172-178
    • /
    • 1992
  • The graft copolymerization of acrylonitrile(AN) onto chitosan film by using $F^{3+}(FeCl_3{\cdot}6H_2O)$ as a photosensitizer in an aqueous medium was carried out under ultraviolet(UV) irradiation. The grafted copolymer was identified by using IR spectroscopy and scanning electron microscope. The effects of various polymerization parameters involving monomer concentration, photosensitizer concentration, polymerization time and polymerization temperature were investigated. As monomer concentration and photosensitizer concentration were increased, the percent grafting was increased up to limiting value. And also the percent grafting was found to increase by increasing the polymerization time and temperature.

  • PDF

The Biologic Effect of Millimeter Wave Irradiation Followed to Photodynamic Therapy on the Tumor

  • Ahn, Jin-Chul;Lee, Chang-Sook;Chang, So-Young;Yoon, Sung-Chul
    • Biomedical Science Letters
    • /
    • v.17 no.1
    • /
    • pp.79-84
    • /
    • 2011
  • Photodynamic therapy consists of a photosensitizer, suitable light source and oxygen. The excitation of the photosensitizer at a cancer mass results in oxidation which would ultimately reduce the mass via apoptosis. Millimeter wave (MMW) therapy has also been known to be effective on cancer cell mass reduction, human cell regeneration and immunity enhancement among the Russian clinicians and scientists. In the present study, the two modalities were combined to achieve synergistic effects while reducing the administration dosage of the photosensitizer, photogem, thus minimizing the side effects. The CT-26 adenocarcinoma cell mass was implanted on mice and the tumors were exposed to a simple MMW irradiation or a combined treatment of MMW and PDT. The treatments continued for 4 weeks and the size of the tumor was measured continuously. The significant therapeutic result of MMW was not found during 4 weeks, preferably more cancer recurrence possibility after MMW irradiation was observed. The results of this study suggest that the combination of MMW irradiation and photodynamic treatment should not be recommended. The result of the MMW treatment alone, however, displayed suppressive effect on cancer cell proliferation for both in vitro and in vivo. The results of the present study suggest that the millimeter wave therapy deserves a further study.

Physical Properties of Light Cured Dental Composite Resin with Novel Photosensitizers (새로운 광증감제를 사용한 치과용 광중합형 복합레진의 기계적 특성)

  • Sun, Gum-Ju;Lee, Hee-Kyung
    • Journal of Technologic Dentistry
    • /
    • v.35 no.4
    • /
    • pp.313-320
    • /
    • 2013
  • Purpose: The purpose of this study was to know the physical properties of UDMA dental composite resins containing two photosensitizers, PD, DA, as a photosensitizer instead of CQ. We want to know Remaining Double Bond(RDB) of UDMA unfilled resin and diametral tensile strength and flexural strength of composite resin containing PD and DA were compared with those of CQ, most widely used photosensitizer for dental composite resins. Methods: The RDB of UDMA studied by FT-IR spectroscopy increased with irradiation time. The composite resins were tested for their physical properties. The dental composite resins were made with UDMA as a monomer, silanized silica as filler, N,N-dimethylaminoethyl methacrylate (DAEM) as amine initiator, and one of the two kinds of new photosensitizers. Results: The relative RDB of UDMA was in the order: DA > CQ > PD but the physical properties of the composite resins show PD and DA with higher results compared with that containing CQ. The reason for the results is that PD and DA serve not only as a photosensitizer but also as a photo-crosslinking agent. Conclusion: PD and DA show as effective photosensizers, suitable for UDMA dental composite resin compare with a higher efficiency than CQ.

Antibacterial effect of Zingiberaceae extracts mediated photodynamic therapy on Streptococcus mutans (Streptococcus mutans에 대한 생강과 천연추출물의 광역학 항균효과)

  • Hwang, Hye-Rim;Kang, Si-Mook;Lee, Eun-song;Kim, Baek-Il
    • The Journal of the Korean dental association
    • /
    • v.57 no.10
    • /
    • pp.560-568
    • /
    • 2019
  • Purpose: This study evaluated the antibacterial effects of curcuma, ginger, and finger root extracts in water-soluble powder on planktonic Streptococcus mutans(S.mutans), which is known to cause dental caries, in order to confirm whether these extracts could perform as photosensitizers for the effects of photodynamic therapy (PDT). Methods: This study used the strain of streptococcus mutans ATCC 25175 distributed by the Korean Collection for Type Cultures of the Korea Research Institute of Bioscience & Biotechnology. Commercial edible curcuma, ginger and finger root were used as the natural extracts for the use of photosensitizer. To extract organic solvent, 3 g of each powder was mixed in $30m{\ell}$ of dimethyl sulfoxide (DMSO, VWR, Germany) before extraction. $1.8m{\ell}$ of the photosensitizer solution, manufactured in the concentrations of 5, 0.5, and $0.05mg/m{\ell}$, was mixed with $0.2m{\ell}$ of the S. mutans culture medium that had been cultured for 2 days. To induce the photodynamic reaction, Qraycam (AIOBIO, Seoul, Korea) equipped with 405 nm LED was used to expose light for 5 minutes to irradiate 59 nW energy for 300 seconds. Results: Compared with the case with no light, a higher photodynamic therapeutic effect was confirmed with $0.05mg/m{\ell}$ curcuma powder extract, the concentration of $0.5mg/m{\ell}$ and LED light of 405 nm wavelength (p=0.000, p=0.003). $0.05mg/m{\ell}$ of curcuma powder extract and the concentration of $0.5mg/m{\ell}$ showed 100% antibacterial effect when exposed to light, whereas the concentration of $5mg/m{\ell}$ showed 11.95% antibacterial effect. When exposed to light, $0.05mg/m{\ell}$ of ginger powder extract showed an antibacterial effect which didn't statistically decrease. The concentrations of $0.5mg/m{\ell}$ and $5mg/m{\ell}$ did not show any antibacterial effects. As a result of examining any photodynamic therapeutic effects of finger root powder extract on S. mutans, no statistically significant effect was found. Conclusion: The curcuma powder extract is expected to perform as a photosensitizer. Even though belonging to the same ginger family, ginger powder and finger root powder seem difficult to perform as photosensitizer.

  • PDF