Hydroxymethyl Phosphonium Research Articles

Reclaimed water use in industrial cooling circuits: Compatibility with TP11 biocides

Cooling water circuits represent a high-water saving potential that has not been fully exploited yet due to the risk of Legionella outbreaks. According to legislation, cooling circuits are subjected to specific biocide treatments which must be considered when water reuse is planned. Biocide effectiveness mainly depends on the type of installation, its operating regime, and the interactions with other chemicals. Therefore, water reuse is critical because its physical, chemical and microbiological characteristics, beside deposit and corrosion problems, may reduce the biocidal power and produce a health risk. However, there is a lack of knowledge on the compatibility of reclaimed water with biocides, and on long-term maintenance problems. This paper validates the long term performance of an industrial cooling tower using reclaimed water, obtained after the treatment of bottle washing water. The compatibility study of the reused water with three non-oxidant commercial products from the TP11 group (quaternary ammonium, tetrakis hydroxymethyl phosphonium sulphate and isothiazolone) shows a reduction lower than 20% of the biocide efficiency between periodic additions. Isothiazolone-based biocide was tested with reclaimed water during 1 year at industrial scale, without detecting any problem. Results show that water quality was always within the values allowed by legislation and slightly better when using reclaimed water (lower ecotoxicity of the purge and higher biocidal residual concentration). With the reuse strategy, water savings of 3750 m3/y were obtained. Furthermore, to minimize the Legionella and corrosion risks, an optimal control of the cooling tower has been developed based on correlations.

Laser Light Trapping Phenomenon in a 3D Radiotherapy Polymer Gel Dosimeter.

This paper aims to explain the phenomenon of laser light trapping (LLT) in a 3D polymer gel dosimeter. A VIC-T polymer gel dosimeter containing 17% N-vinylpyrrolidone, 8% N,N′-methylenebisacrylamide, 12% tert-butyl alcohol, 5% gelatine, 0.02% hydroquinone and 14 mM tetrakis(hydroxymethyl)phosphonium chloride was used in this study. It was exposed to green laser light with a wavelength of 532 nm. A film was recorded during the exposure. After exposure, Raman spectroscopy was used to study the reactions taking place inside the dosimeter. The obtained results were used to explain what the LLT phenomenon is, what are the consequences for the dosimeter in which such a phenomenon occurs, and what dosimeter components play an important role in the occurrence of LLT. In addition, the conditions under which 3D polymer gel dosimeters can be measured using optical computed tomography at short wavelengths of visible laser light are indicated.

Tetrakis hydroxymethyl phosphonium sulfate (THPS) with biopolymer as strategy for the control of microbiologically influenced corrosion in a dynamic system

In this study, satisfactory efficacy was found from the combination of the biocide THPS with the xanthan biopolymer for the control of microbiologically influenced corrosion in SAE 1010 carbon steel. The effectiveness of this combination was compared with three systems: without treatment and using THPS and xanthan in isolation. The experiments were carried out in a turbulent flow looping, in which the circulating medium was seawater. Quantification of microbial groups, corrosion rate measurements through mass loss, quantification of biomass and extracellular polymeric substances (EPS) of the biofilm were performed. The biofilm on the coupons was analyzed using the scanning electron microscope (SEM), and X-ray diffraction (XRD) was used to identify the crystallographic phases of the corrosion products. The results showed that, even with low concentration of xanthan added, the THPS + xanthan system had a greater reduction of microbial groups in relation to the other systems. This combination also reduced biomass and extracellular polymeric substances. Despite the presence of grooves, SEM indicated that xanthan forms a more adherent film on steel due to its dispersant property. And, finally, the lepidocrocyte phase was not found in the corrosion products from systems with THPS, whereas mackinawite phase was found.

Visualization of Penetration and Reaction of Aldehyde Tanning Agent in Leather using Fluorescence Technique

Penetration and reaction of tanning agents in leather greatly influence tanning performance and leather quality. Aldehyde tanning agents are widely used in leather manufacture, but their penetration and reaction in leather cannot be detected easily. Considering the fact that aldehyde can form a fluorescent Schiff base with amino groups of collagen, we visualized the distribution and reactivity of typical aldehyde tanning agents in leather during tanning process using a fluorescence microscope. The results showed that glutaraldehyde in leather was easily observed under the fluorescein isothiocyanate (FITC) filter system. The fluorescence intensity of pelt/leather gradually increased with penetrating of glutaraldehyde, basifying and heating, which was consistent with the formation of Schiff base and the increase in Ts of pelt/leather. Oxidized sodium alginate and dialdehyde sodium carboxymethyl cellulose in leathers were also detected using a fluorescence microscope because the aldehyde group of the two tanning agents formed a fluorescent Schiff base with amino groups of collagen. The oxazolidine tanned leather and the tetrakis hydroxymethyl phosphonium tanned leather emitted little fluorescence because they crosslinked collagen with hydroxymethyl group. These results indicate the fluorescent technique is useful to visualize the penetration and reaction of aldehyde tanning agents that crosslink collagen with aldehyde groups.

Fixation of the Color of Naturally Colored Domestic Silk by Cross-Linking the Sericin with Tetrakis (Hydroxymethyl) Phosphonium Sulfate

The pigment of naturally colored domestic silk (NCDS) is present in the sericin layer rather than in the silk fibroin, and the color losses easily during the wet process accompanied by dissolution of the sericin. In this study, the sericin of naturally colored domestic silk was cross-linked to a water-insoluble network via treatment with a hydroxyalkyl phosphine compound, tetrakis (hydroxymethyl) phosphonium sulfate (THPS). The effects of reaction conditions, such as pH, reagent concentration, reaction temperature, and time on the cross-linking effect were investigated. Cross-linking the NCDS samples at a relatively good condition could decrease the weight loss from initial 16.7 % to less than 4.5 % during degumming. The cross-linked NCDS showed a K/S value (color depth) 1.84 times higher than the uncross-linked sample after 20 cycles of washing. The method for fixing the color of NCDS offers a kind of solution with high practicality and low cost. The cross-linker proposed in this study could also be an alternative for cross-linking sericin based materials.

Mixtures of tetrakis hydroxymethyl phosphonium chloride and ammonium influence plankton community structure in blackwater pond mesocosms

Abstract Mixtures of chemicals from human sources are pervasive in aquatic systems, yet their effects on aquatic communities are relatively understudied. Emerging contaminants such as organophosphorus flame-retardants (e.g. tetrakis hydroxymethyl phosphonium chloride (THPC)), are toxic to planktonic species at environmentally relevant concentrations. Additionally, inorganic ammonium from agriculture and industry is likely to enter surface waters simultaneously with flame retardant chemicals. While effects of ammonium on plankton are known, its presence has the potential to influence the toxicity of other contaminants. To study mixture effects on plankton communities, floating mesocosms were dosed with THPC (0.08 or 0.8 mg L−1) with or without ammonium (0.3 mg L−1). Weekly measurements of zooplankton community composition and phytoplankton abundance (as chlorophyll a) were performed. Each factor alone had no effect on zooplankton abundance or species composition. However, the mixture decreased the proportion of calanoid copepods and increased rotifers during weeks 1–3. Chlorophyll a was unaffected by treatments, but concentrations were highly variable for the duration of the experiment. The interaction between THPC and ammonium suggests that the contaminants together reduce abundance of large zooplankton, releasing smaller zooplankton from predation and competitive pressure while potentially limiting food availability to planktivorous fish.

Simulation of Water Equivalency of Polymer Gel Dosimeters with GAMOS

Purpose: Polymer gel materials are used as dosimeters to provide three dimensional radiation dose distribution. An ideal gel dosimeter should offer radiological properties equivalent to water. This study aims to determine and compare the water equivalencies of various new polymer gel mixtures using Geant4-based Architecture for Medicine-Oriented Simulations GAMOS software program. Methods: To do this, percentage depth dose curves of the simulated polymer gel mixtures were compared with water curves. Different combinations of materials from 2 main classes were used in the mixtures: 1 Sodium Carboxymethyl Cellulose SODIUM CMC , Polyvinyl Alcohol PVA and Polyethylene Glycol PEG as gel matrix, 2 2-Hydroxyethyl Methacrylate HEMA , 1-Vinyl-2-Pyrrolidinone VP and Diethylene Glycol Dimethacrylate DEGDMA as monomer. Each mixture also contained ultra-pure water and an antioxidant material called Tetrakis Hydroxymethyl Phosphonium Chloride THPC . Results: Percentage depth doses of gel mixtures and water was calculated for 6, 18 MV and 50, 70, 100, 150 kVp X rays. The mixture sample showing radiological behavior nearest to water over all energies was observed to be 31a Water, PEG, HEMA, THPC , while the largest difference is observed in 11a Water, SODIUM CMC, HEMA, THPC .Conclusion: As a result, simulated gel formulations were found to be radiologically water equivalent.

Effect of pH on acidic and basic chelating agents used in the removal of iron sulfide scales: A computational study

Iron sulfide scale is a major challenge in the upstream section of the oil and gas industry. It is responsible for precipitate formation in tubulars, and it damages equipment. This leads to a loss in production. Mechanical and chemical treatment are methods used in scale removal. However, the former causes a Cobra effect by making things worse due to corrosion. Hence, chemical treatments are more widely used. THPS (Tetrakis hydroxymethyl phosphonium sulfate) and DTPA (diethylenetriaminepentaacetic acid) which are acidic and basic respectively are chelating agents which are part of the chemical methods used in the removal of iron sulfide scales. However, they are used at extreme pH conditions. Herein, the pH effects on the chelating ability are studied via binding affinity to the central metal ion using DFT (Density Functional Theory) calculations. The robust B3LYP (Becke's 3 Lee Yang and Parr) parameter exchange-correlation functional was employed in this study. The binding affinity of THPS to the central metal ion decreased as the deprotonation increased despite forming six coordinate bonds with the central metal ion whereas in DTPA the binding affinity increased as the protonation increased and formed seven coordinated bonds to the central metal ion. Therefore, DTPA can be used more effectively if the pH is reduced to a neutral pH. The results herein provide molecular insights in understanding the possibility of using DTPA effectively in mild condition while still increasing its chelating power in removing iron sulfide scales.

A sea anemone-inspired small synthetic peptide at sub-ppm concentrations enhanced biofilm mitigation

A biocide enhancer is a chemical that can enhance the efficacy of a biocide or reduce its dosage. In this work, a novel peptide was tested as a biocide enhancer. A chemically synthesized 14-mer peptide (Peptide A), which was found non-biocidal, has an amino acid sequence derived from sea anemone Actinia equina that possesses a biofilm-free exterior. Peptide A at 180 ppb (w/w) or 100 nM enhanced 100 ppm tetrakis hydroxymethyl phosphonium sulfate (THPS) against an oilfield biofilm consortium grown on C1018 carbon steel in an enriched artificial seawater medium. The combination of 100 nM Peptide A + 100 ppm THPS led to additional 2-log reduction, 1-log reduction, 1-log reduction in sessile sulfate reducing bacteria (SRB) cell count, sessile acid producing bacteria (APB) cell count, and sessile general heterotrophic bacteria (GHB) cell count, in comparison with the treatment using 100 ppm THPS alone in a 14-day laboratory biofilm prevention test. The data in this work suggest that non-biocidal Peptide A is a promising biocide enhancer that should be further explored.

Fabrication and dual imaging properties of quantum dot/silica core-shell particles immobilized with gold nanoparticles

ABSTRACTThe present work proposes a preparation method for core-shell nanoparticles composed of quantum dots (QDs), SiO2, large Au nanoparticles (AuL), and small Au nanoparticles (AuS). The QDs were silica-coated with a sol-gel method using tetraethyl orthosilicate (QD/SiO2). AuL and AuS were fabricated by reducing Au3+ ions with sodium citrate and tetrakis(hydroxymethyl)phosphonium chloride in water, respectively. Amino groups were introduced onto QD/SiO2 surface by using (3-aminopropyl)-triethoxysilane (QD/SiO2/NH2). Both AuL and AuS were immobilized on QD/SiO2/NH2 by successively reacting AuL and AuS with QD/SiO2/NH2 (QD/SiO2/NH2/AuL/AuS). Surface modification of QD/SiO2/NH2/AuL/AuS was performed by using polyethylene glycol (PEG) with a thiol group (QD/SiO2/NH2/AuL/AuS/PEG). The QD/SiO2/NH2/AuL/AuS/PEG colloid solution could be clearly imaged via its fluorescence. Its computed tomography (CT) value per unit concentration of Au (M) was 1.2 × 104 HU/M. The QD/SiO2/NH2/AuL/AuS/PEGs were circulated in a mouse through blood vessels, and some of them became trapped and accumulated in the liver and spleen.

Effect of long term application of tetrakis(hydroxymethyl)phosphonium sulfate (THPS) in a light oil-producing oilfield

Samples of (I) produced waters, (II) central processing facility (CPF) waters and (III) pipeline solids were collected from a light oil-producing field. The biocide, tetrakis(hydroxymethyl)phosphonium sulfate (THPS) was routinely used in the CPF. Samples monitoring indicated that THPS was effective in microbial control but also increased concentrations of sulfate and phosphate in transitioning from Type I to Type II waters. Type II waters had high concentrations (up to 60 mM) of acetate but low most probable numbers (MPNs) of acid-producing and sulfate-reducing bacteria, indicating the presence of active biocide, as high MPNs were found in Type I waters. Solids had high phosphate and high MPNs, indicating that THPS was inactive. Solids had oil and an anaerobic community dominated by Acetobacterium, which may contribute to conversion of oil to acetate. The presence of THPS prevented the use of this acetate in Type II waters, where it accumulated to unusually high concentrations.

Abstract 3710: Nanoparticle-mediated concomitant radiation dose amplification and PARP inhibition in lung cancer

Abstract Introduction: More than 50% of cancer patients receive radiation therapy at some point during their care. Gold nanoparticles (GNPs) can amplify the radiation dose by facilitating the ejection of low-energy photoelectrons, resulting in increased DNA damage. One of the main challenges of radiation therapy in cancer is to sustain this damage for longer durations. DNA single-strand breaks (SSBs) are repaired by base excision repair, which utilizes Poly(ADP-ribose) polymerase (PARP). PARP inhibition during radiotherapy provides an attractive alternative in maximizing treatment outcomes. Here, we explore a strategy to combine the radiosensitizing effect of GNPs with the DNA-repair inhibiting ability of NanoTalazoparib (nTLZ), a liposomal formulation of the PARP inhibitor, talazoparib (TLZ). Methods: GNPs were synthesized by reducing AuCl4 using Tetrakis(hydroxymethyl)phosphonium chloride and further PEGylating using heterobifunctional PEGs. A liposomal formulation of TLZ was synthesized using the Nanoassemblr, a microfluidics-based device. Physicochemical characterization of GNPs and nTLZ was carried out using TEM, DLS and release kinetics studies. In vitro studies were carried out to assess the toxicity of the GNPs using MTT assay in non-small cell lung cancer (NSCLC) cell line Calu-6. The therapeutic efficacy of combination treatment using GNPs, nTLZ and radiation was done using clonogenic survival assays. Clonogenic assay was carried out using Calu 6 cells, which were sequentially treated with GNPs (1mg/mL), TLZ (0.5 uM) and nTLZ (0.5 uM) with and without radiation. The radiation doses varied from 0-10Gy for each set of treatments. Results: PEGylated GNP's showed a hydrodynamic diameter of ~10-12 nm with a spherical morphology whereas nTLZ size was 70 nm encapsulating TLZ at a concentration of ~200 ug/ml. MTT assay showed no toxicity for PEGylated GNPs treated upto a concentration of 3.0 mg/mL. Cells treated with either GNPs, TLZ or nTLZ did not show significant reduction in colony formation, but were reduced with increasing doses of radiation. The survival plots showed a highly additive antiproliferative effect for the GNP + nTLZ combination at all radiation doses, while the free TLZ + GNPs combination was not as effective at inhibiting colony formation. In vivo experiments assessing the combination therapy in a subcutaneous xenograft mice model using Calu 6 are currently under way. Conclusions: The preliminary in vitro results indicate that the combination of radiosensitizing GNPs with a potent DNA repair enzyme inhibitor, TLZ, has an immense potential as a complimentary combination therapy in conjunction with radiation therapy in treatment of lung cancer. This work is supported by the CaNCURE program (grant #1CA174650-02), American Lung Association, Dana-Farber Cancer Institute and Brigham and Women's Hospital. Citation Format: Ana G. Vazquez-Pagan, Paige Baldwin, Ravina M. Ashtaputre, Sijumon Kunjachan, Srinivas Sridhar, Rajiv Kumar, Ross Berbeco. Nanoparticle-mediated concomitant radiation dose amplification and PARP inhibition in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3710.

Application of bi-nanoparticle on dose enhancement effect in two different polymer gel dosimeter using spectrophotometer.

This study aimed at proving the ability of bismuth-nanoparticle (Bi-np) in dose enhancement effect (DEE) using the polymer gel dosimeter. Two different polymer gels, namely poly acrylamide gelatin tetrakis hydroxymethyl phosphonium chloride (PAGAT) and N-isopropylacrylamide (NIPAM) gels were chosen for this study. The gels were doped with Bi-np particle with various concentrations of 0.5 mM, 1 mM, and 2.5 mM and were then irradiated with a CO-60 gamma radiation source of energy 1.25 MeV. Gel samples were analyzed by spectrophotometer. The dose enhancement factor (DEF) was calculated for both gels for all concentrations of Bi-np particle. The higher DEF for PAGAT and NIPAM was calculated as 1.3415 and 1.1823, respectively, for 0.5 mM concentration of Bi-np. From our results, we infer that 0.5 mM is the optimal concentration in polymer gel to obtain good DEEs in the energy range of 1.25 MeV.

Enhanced Biocide Treatments with D-amino Acid Mixtures against a Biofilm Consortium from a Water Cooling Tower.

Different species of microbes form mixed-culture biofilms in cooling water systems. They cause microbiologically influenced corrosion (MIC) and biofouling, leading to increased operational and maintenance costs. In this work, two D-amino acid mixtures were found to enhance two non-oxidizing biocides [tetrakis hydroxymethyl phosphonium sulfate (THPS) and NALCO 7330 (isothiazoline derivatives)] and one oxidizing biocide [bleach (NaClO)] against a biofilm consortium from a water cooling tower in lab tests. Fifty ppm (w/w) of an equimass mixture of D-methionine, D-leucine, D-tyrosine, D-tryptophan, D-serine, D-threonine, D-phenylalanine, and D-valine (D8) enhanced 15 ppm THPS and 15 ppm NALCO 7330 with similar efficacies achieved by the 30 ppm THPS alone treatment and the 30 ppm NALCO 7330 alone treatment, respectively in the single-batch 3-h biofilm removal test. A sequential treatment method was used to enhance bleach because D-amino acids react with bleach. After a 4-h biofilm removal test, the sequential treatment of 5 ppm bleach followed by 50 ppm D8 achieved extra 1-log reduction in sessile cell counts of acid producing bacteria, sulfate reducing bacteria, and general heterotrophic bacteria compared with the 5 ppm bleach alone treatment. The 10 ppm bleach alone treatment showed a similar efficacy with the sequential treatment of 5 ppm bleach followed by 50 ppm D8. The efficacy of D8 was found better than that of D4 (an equimass mixture of D-methionine, D-leucine, D-tyrosine, and D-tryptophan) in the enhancement of the three individual biocides against the biofilm consortium.

Enhancing sludge biodegradability and volatile fatty acid production by tetrakis hydroxymethyl phosphonium sulfate pretreatment

A new pretreatment method based on tetrakis hydroxymethyl phosphonium sulfate (THPS) biocide was tried to enhance sludge disintegration, and improved sludge biodegradability and subsequent volatile fatty acid (VFA) production. Sludge activity decreased to less than 10% after 2 days pretreatment using 20mg/g-TSS THPS, which also obviously destroyed EPS and cell membrane, and dissolved more biodegradable substances (48.8%) than raw sludge (19.7%). Moreover, 20mg/g-TSS THPS pretreatment shortened fermentation time to 4days and improved VFA production to 2778mg COD/L (4.35 times than that in control). Therein, the sum of n-butyric, n-valeric and iso-valeric acids unexpectedly accounted for 60.5% of total VFA (only 20.1% of that in control). The more high molecular weight VFAs (C4-C5) than low molecular VFAs (C2-C3) resulted from THPS pretreatment benefited to subsequent medium-chain volatile acids (C6-C12) generation to realize the separation and recovery of organic carbon more efficiently.

Study on the thermal decomposition kinetics and flammability performance of a flame-retardant leather

A flame-retardant leather (FR-leather) was prepared from blue wet leather treated with tetrakis hydroxymethyl phosphonium–melamine–pentaerythritol diphosphorate (THPM). An optimized genetic algorithm search method driven by Kissinger method was employed to estimate pyrolysis kinetic mechanism and the thermal stability of FR-leather. It is shown that the thermal decomposition of leather in nitrogen is a three-step kinetic scheme composed of the pyrolysis of triglyceride, multi-complexation collagen and single-complexation collagen, and the activation energies of the corresponding components of FR-leather are, respectively, 84.1, 172.6 and 253.6 kJ mol−1. Accordingly, those of blank leather are 69.3, 161.3 and 105.4 kJ mol−1. Meanwhile, cone calorimeter test demonstrates that when leather was treated with THPM, total heat release and total smoke production are decreased, respectively, 16.2 and 54.5%, and time to ignition increased from 20 s of blank leather to 26 s of FR-leather. The results of limit oxygen index value increased from 26.1% of blank leather to 32.9% of FR-leather, and the results of UL-94 vertical burning tests of FR-leather are significantly decreased, such as flame combustion time and length of carbonization decreased 88% and 72%, respectively. It is shown that the novel THPM material obviously improved the thermal stability and flame-retardant properties of leather fibers; at the same time, it has good smoke suppression effect and is an excellent flame retardant suitable for leather.

The exploration of the effective methods to evaluate the stripping ability of bacteriacide to SRB biofilm

Purpose The purpose of this paper was to study some effective evaluation methods for the biocide performance on sulfate-reducing bacteria (SRB) biofilm. Design/methodology/approach The most probable number method, electrochemical impedance spectroscopy (EIS) measurements, scanning electron microscopy (SEM), three-dimensional (3D) photos and epifluorescent microscopy were used in this study. Findings The results showed that the minimum inhibitory concentrations and minimum bactericidal concentrations of them to sessile SRB were greatly more than planktonic SRB. The EIS of the two biocides indicated that the biofilm exposed to higher concentrations of biocide were much more compact and flat, which perfectly coincided with the SEM, 3D photos and the epifluorescent microscopies. Originality/value In this paper, it, thus, appears that these methods evaluating biocide performance on the SRB biofilm were really effective by comparing the performance of bis-quaternary ammonium salt (BAQS) and tetrakis hydroxymethyl phosphonium sulfate.

Synthesis of 1-substituted 2,6,7-trioxa-4-phospha-1-borabicyclo[2.2.2]octan-1-uide

ABSTRACT1-Substituted 2,6,7-trioxa-4-phospha-1-borabicyclo[2.2.2]octan-1-uides were obtained in 31–71% yields by the reaction of tetrakis(hydroxymethyl)phosphonium sulfate with alkyl- or arylboronic acids in the presence of tetrabutylammonium hydroxide.

Enhanced Biocide Mitigation of Field Biofilm Consortia by a Mixture of D-Amino Acids.

Microbiologically influenced corrosion (MIC) is a major problem in the oil and gas industry as well as in many other industries. Current treatment methods rely mostly on pigging and biocide dosing. Biocide resistance is a growing concern. Thus, it is desirable to use biocide enhancers to improve the efficacy of existing biocides. D-Amino acids are naturally occurring. Our previous work demonstrated that some D-amino acids are biocide enhancers. Under a biocide stress of 50 ppm (w/w) hydroxymethyl phosphonium sulfate (THPS) biocide, 1 ppm D-tyrosine and 100 ppm D-methionine used separately successfully mitigated the Desulfovibrio vulgaris biofilm on carbon steel coupons. The data reported in this work revealed that 50 ppm of an equimolar mixture of D-methionine, D-tyrosine, D-leucine, and D-tryptophan greatly enhanced 50 ppm THPS biocide treatment of two recalcitrant biofilm consortia containing sulfate reducing bacteria (SRB), nitrate reducing bacteria (NRB), and fermentative bacteria, etc., from oil-field operations. The data also indicated that individual D-amino acids were inadequate for the biofilm consortia.

Synergetic effect of green tea on polymer gel dosimeter and determination of optimal wavelength to choose light source for optical computed tomography

Purpose: The ultimate aim of this study is to observe the effect of Green tea as a co-antioxidant in PAGAT gel dosimeter and evaluate the appropriate light source for scanning the PAGAT and NIPAM polymer gel. Methods: Both PAGAT (Poly Acrylamide Gelatin Tetrakis hydroxyl phosphonium chloride) and NIPAM (N-Isopropyl acrylamide) gel were prepared in normoxic condition. The green tea extract (GTE) was prepared and tested only on PAGAT. Co-60 teletherapy machine has been used for irradiation purpose, and the gel samples were scanned using UV-Visible spectrophotometer. Water equivalency of the gel has been tested in terms of their electron density, effective atomic number and Ratio of oxygen and hydrogen (O/H). We have used NIST XCOM database to test the water equivalency. Results: In this study we found that the GTE added to the gel do not respond to the given doses. By adding sugar we can enhance the sensitivity of the gel. Further investigations are required to use Green tea as a co antioxidant concentration of THPC (Tetrakis hydroxymethyl phosphonium chloride). The optimal wavelength with different region for scanning the PAGAT is 450 to 480 nm (Blue region), for NIPAM it is 540 nm and 570 nm (Green and yellow region). The PAGAT and NIPAM showed better sensitivity at 510 nm. Both gels have their effective atomic number closer to water (NIPAM-7.2, PAGAT-7.379). Conclusion: As per our results, we concluded that GTE alone is not an effective co-antioxidant for polymer gels. When the GTE is combined with sugar and THPC, it protects the gel from pre-polymerization. This study strongly suggests that the blue light is an optimal source for scanning the PAGAT and green to yellow light for NIPAM gel. Though both gels were considered as water equivalent, the PAGAT is equivalent to water and the temporal stability of this gel is higher than NIPAM.