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James B Fink - One of the best experts on this subject based on the ideXlab platform.

  • Quantifying Delivered Dose with Jet and Mesh Nebulizers during Spontaneous Breathing, Noninvasive Ventilation, and Mechanical Ventilation in a Simulated Pediatric Lung Model with Exhaled Humidity
    'MDPI AG', 2021
    Co-Authors: Arzu Ari, James B Fink
    Abstract:

    Acutely ill children may transition between spontaneous breathing (SB), noninvasive ventilation (NIV), and mechanical ventilation (MV), and commonly receive the same drug dosage with each type of ventilatory support and interface. This study aims to determine the aerosol deposition with jet (JN) and mesh nebulizers (MN) during SB, NIV, and MV using a pediatric lung model. Drug delivery with JN (Mistymax10) and MN (Aerogen Solo) was compared during SB, NIV, and MV using three different lung models set to simulate the same breathing parameters (Vt 250 mL, RR 20 bpm, I:E ratio 1:3). A heated humidifier was placed between the Filter and test lung to simulate exhaled humidity (35 ± 2 °C, 100% RH) with all lung models. Albuterol sulfate (2.5 mg/3 mL) was delivered, and the drug deposited on an Absolute Filter was eluted and analyzed with spectrophotometry. Aerosol delivery with JN was not significantly different during MV, NIV, and SB (p = 0.075), while inhaled dose obtained with MN during MV was greater than NIV and SB (p = 0.001). The delivery efficiency of MN was up to 3-fold more than JN during MV (p = 0.008), NIV (p = 0.005), and SB (p = 0.009). Delivered dose with JN was similar during MV, NIV, and SB, although the delivery efficiency of MN differs with different modes of ventilation

  • Delivered dose with jet and mesh nebulisers during spontaneous breathing, noninvasive ventilation and mechanical ventilation using adult lung models
    'European Respiratory Society (ERS)', 2021
    Co-Authors: Arzu Ari, James B Fink
    Abstract:

    What is the delivered dose with jet and mesh nebulisers during spontaneous breathing (SB), noninvasive ventilation (NIV), and mechanical ventilation (MV) using an adult lung model with exhaled humidity (EH)? The delivery of salbutamol sulfate (2.5 mg per 3 mL) with jet (Mistymax10) and mesh nebulisers (Aerogen Solo) was compared during SB, NIV, and MV using breathing parameters (tidal volume 450 mL, respiratory rate 20 breaths per min, inspiratory:expiratory ratio 1:3) with three lung models simulating exhaled humidity. A manikin was attached to a sinusoidal pump via a Filter at the bronchi to simulate an adult with SB. A ventilator (V60) was attached via a facemask to a manikin with a Filter at the bronchi connected to a test lung to simulate an adult receiving NIV. A ventilator-dependent adult was simulated through a ventilator (Servo-i) operated with a heated humidifier (Fisher & Paykel) attached to an endotracheal tube (ETT) with a heated-wire circuit. The ETT was inserted into a Filter (Respirgard II). A heated humidifier was placed between the Filter and test lung to simulate exhaled humidity (35±2°C, 100% relative humidity). Nebulisers were placed at the Y-piece of the inspiratory limb during MV and positioned between the facemask and the leak-port during NIV. A mouthpiece was used during SB. The delivered dose was collected in an Absolute Filter that was attached to the bronchi of the mannequin during each aerosol treatment and measured with spectrophotometry. Drug delivery during MV was significantly greater than during NIV and SB with a mesh nebuliser (p=0.0001) but not with a jet nebuliser (p=0.384). Delivery efficiency of the mesh nebuliser was greater than the jet nebuliser during MV (p=0.0001), NIV (p=0.0001), and SB (p=0.0001). Aerosol deposition obtained with a mesh nebuliser was greater and differed between MV, NIV, and SB, while deposition was low with a jet nebuliser and similar between the modes of ventilation tested

  • characterization of ribavirin aerosol with small particle aerosol generator and vibrating mesh micropump aerosol technologies
    Respiratory Care, 2016
    Co-Authors: Brian K Walsh, Peter Betit, James B Fink, Luis M Pereira, John H. Arnold
    Abstract:

    BACKGROUND: Ribavirin is an antiviral drug that can be administered by inhalation. Despite advancements in the oral delivery of this medication, there has been a renewed interested in delivering ribavirin via the pulmonary system. Although data are not conclusive that inhaled ribavirin improves outcomes, we set out to determine whether delivery by a newer generation nebulizer, the vibrating mesh micropump, was as effective as the recommended small-particle aerosol generator system. METHODS: We compared the physicochemical makeup and concentrations of ribavirin before and after nebulization with 0.9% NaCl and sterile water. An Andersen cascade impactor was used to determine particle size distribution and mass median aerodynamic diameter, and an Absolute Filter was used to measure total aerosol emitted output and inhaled dose during mechanical ventilation and spontaneous breathing. Ribavirin was analyzed and quantified using high-performance liquid chromatography with tandem mass spectrometric detection. RESULTS: Ribavirin was found to be stable in both 0.9% aqueous NaCl and sterile water with an r2 value of 0.96 and identical coefficients of variation with no difference in drug concentration before and after nebulization with the vibrating mesh micropump. The small-particle aerosol generator produced a smaller mass median aerodynamic diameter (1.84 μm) than the vibrating mesh micropump (3.63 μm, P = .02); however, there was no significant difference in the proportion of drug mass in the 0.7–4.7-μm particle range. Total drug delivery was similar with the small-particle aerosol generator and vibrating mesh micropump in both spontaneously breathing ( P = .77) and mechanical ventilation ( P = .48) models. CONCLUSIONS: The vibrating mesh micropump nebulizer may provide an effective alternative to the small-particle aerosol generator in administration of ribavirin using NaCl or sterile water, both on and off the ventilator. Further clinical studies are needed to compare efficacy.

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Arzu Ari, Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O(2)) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (V(t)) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O(2) (100%) and heliox (80/20% mixture). A total of 12 runs, using O(2) and heliox were conducted at 3 and 6 L/min (n = 3). Drug was collected on an Absolute Filter, eluted and measured using spectrophotometry. The percent inhaled dose (mean ± SD) was similar with heliox and O(2) at 3 L/min (11.41 ± 1.54 and 10.65 ± 0.51, respectively; P = 0.465). However at 6 L/min drug deposition was ≥ 2-fold greater with heliox (5.42 ± 0.54) than O(2) (1.95 ± 0.50; P = 0.01). Using a pediatric model of HFNC, reducing delivered flow from 6 to 3 L/min increased inhaled albuterol delivery ≥ 2-fold but eliminated the increase in inhaled drug efficiency associated with heliox.

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Summary. Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O2) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (Vt) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O2 (100%) and heliox (80/20% mixture). A total of 12 runs, using O2 and heliox were conducted at 3 and 6 L/ min (n ¼ 3). Drug was collected on an Absolute Filter, eluted and measured using spectropho

Robert Harwood - One of the best experts on this subject based on the ideXlab platform.

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Arzu Ari, Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O(2)) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (V(t)) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O(2) (100%) and heliox (80/20% mixture). A total of 12 runs, using O(2) and heliox were conducted at 3 and 6 L/min (n = 3). Drug was collected on an Absolute Filter, eluted and measured using spectrophotometry. The percent inhaled dose (mean ± SD) was similar with heliox and O(2) at 3 L/min (11.41 ± 1.54 and 10.65 ± 0.51, respectively; P = 0.465). However at 6 L/min drug deposition was ≥ 2-fold greater with heliox (5.42 ± 0.54) than O(2) (1.95 ± 0.50; P = 0.01). Using a pediatric model of HFNC, reducing delivered flow from 6 to 3 L/min increased inhaled albuterol delivery ≥ 2-fold but eliminated the increase in inhaled drug efficiency associated with heliox.

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Summary. Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O2) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (Vt) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O2 (100%) and heliox (80/20% mixture). A total of 12 runs, using O2 and heliox were conducted at 3 and 6 L/ min (n ¼ 3). Drug was collected on an Absolute Filter, eluted and measured using spectropho

Arzu Ari - One of the best experts on this subject based on the ideXlab platform.

  • Quantifying Delivered Dose with Jet and Mesh Nebulizers during Spontaneous Breathing, Noninvasive Ventilation, and Mechanical Ventilation in a Simulated Pediatric Lung Model with Exhaled Humidity
    'MDPI AG', 2021
    Co-Authors: Arzu Ari, James B Fink
    Abstract:

    Acutely ill children may transition between spontaneous breathing (SB), noninvasive ventilation (NIV), and mechanical ventilation (MV), and commonly receive the same drug dosage with each type of ventilatory support and interface. This study aims to determine the aerosol deposition with jet (JN) and mesh nebulizers (MN) during SB, NIV, and MV using a pediatric lung model. Drug delivery with JN (Mistymax10) and MN (Aerogen Solo) was compared during SB, NIV, and MV using three different lung models set to simulate the same breathing parameters (Vt 250 mL, RR 20 bpm, I:E ratio 1:3). A heated humidifier was placed between the Filter and test lung to simulate exhaled humidity (35 ± 2 °C, 100% RH) with all lung models. Albuterol sulfate (2.5 mg/3 mL) was delivered, and the drug deposited on an Absolute Filter was eluted and analyzed with spectrophotometry. Aerosol delivery with JN was not significantly different during MV, NIV, and SB (p = 0.075), while inhaled dose obtained with MN during MV was greater than NIV and SB (p = 0.001). The delivery efficiency of MN was up to 3-fold more than JN during MV (p = 0.008), NIV (p = 0.005), and SB (p = 0.009). Delivered dose with JN was similar during MV, NIV, and SB, although the delivery efficiency of MN differs with different modes of ventilation

  • Delivered dose with jet and mesh nebulisers during spontaneous breathing, noninvasive ventilation and mechanical ventilation using adult lung models
    'European Respiratory Society (ERS)', 2021
    Co-Authors: Arzu Ari, James B Fink
    Abstract:

    What is the delivered dose with jet and mesh nebulisers during spontaneous breathing (SB), noninvasive ventilation (NIV), and mechanical ventilation (MV) using an adult lung model with exhaled humidity (EH)? The delivery of salbutamol sulfate (2.5 mg per 3 mL) with jet (Mistymax10) and mesh nebulisers (Aerogen Solo) was compared during SB, NIV, and MV using breathing parameters (tidal volume 450 mL, respiratory rate 20 breaths per min, inspiratory:expiratory ratio 1:3) with three lung models simulating exhaled humidity. A manikin was attached to a sinusoidal pump via a Filter at the bronchi to simulate an adult with SB. A ventilator (V60) was attached via a facemask to a manikin with a Filter at the bronchi connected to a test lung to simulate an adult receiving NIV. A ventilator-dependent adult was simulated through a ventilator (Servo-i) operated with a heated humidifier (Fisher & Paykel) attached to an endotracheal tube (ETT) with a heated-wire circuit. The ETT was inserted into a Filter (Respirgard II). A heated humidifier was placed between the Filter and test lung to simulate exhaled humidity (35±2°C, 100% relative humidity). Nebulisers were placed at the Y-piece of the inspiratory limb during MV and positioned between the facemask and the leak-port during NIV. A mouthpiece was used during SB. The delivered dose was collected in an Absolute Filter that was attached to the bronchi of the mannequin during each aerosol treatment and measured with spectrophotometry. Drug delivery during MV was significantly greater than during NIV and SB with a mesh nebuliser (p=0.0001) but not with a jet nebuliser (p=0.384). Delivery efficiency of the mesh nebuliser was greater than the jet nebuliser during MV (p=0.0001), NIV (p=0.0001), and SB (p=0.0001). Aerosol deposition obtained with a mesh nebuliser was greater and differed between MV, NIV, and SB, while deposition was low with a jet nebuliser and similar between the modes of ventilation tested

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Arzu Ari, Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O(2)) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (V(t)) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O(2) (100%) and heliox (80/20% mixture). A total of 12 runs, using O(2) and heliox were conducted at 3 and 6 L/min (n = 3). Drug was collected on an Absolute Filter, eluted and measured using spectrophotometry. The percent inhaled dose (mean ± SD) was similar with heliox and O(2) at 3 L/min (11.41 ± 1.54 and 10.65 ± 0.51, respectively; P = 0.465). However at 6 L/min drug deposition was ≥ 2-fold greater with heliox (5.42 ± 0.54) than O(2) (1.95 ± 0.50; P = 0.01). Using a pediatric model of HFNC, reducing delivered flow from 6 to 3 L/min increased inhaled albuterol delivery ≥ 2-fold but eliminated the increase in inhaled drug efficiency associated with heliox.

  • evaluation of aerosol generator devices at 3 locations in humidified and non humidified circuits during adult mechanical ventilation
    Respiratory Care, 2010
    Co-Authors: Arzu Ari, Hasan Areabi, James B Fink
    Abstract:

    BACKGROUND: The position of the jet or ultrasonic nebulizer in the ventilator circuit impacts drug delivery during mechanical ventilation, but has not been extensively explored, and no study has examined all of the commonly used nebulizers. METHODS: Drug delivery from jet, vibratingmesh, and ultrasonic nebulizers and pressurized metered-dose inhaler (pMDI) with spacer was compared in a model of adult mechanical ventilation, with heated/humidified and non-humidified ventilator circuits. Albuterol sulfate was aerosolized at 3 circuit positions: (1) between the endotracheal tube and the Y-piece; (2) 15 cm from Y-piece; and (3) 15 cm from the ventilator, with each device (n 3) using adult settings (tidal volume 500 mL, ramp flow pattern, 15 breaths/min, peak inspiratory flow 60 L/min, and PEEP 5 cm H2O). The drug deposited on an Absolute Filter distal to an 8.0-mm inner-diameter endotracheal tube was eluted and analyzed via spectrophotometry (276 nm), and is reported as mean SD percent of total nominal or emitted dose. RESULTS: The vibrating-mesh nebulizer, ultrasonic nebulizer, and pMDI with spacer were most efficient in position 2 with both non-humidified (30.2 1.0%, 24.7 4.4%, and 27.8 3.3%, respectively) and heated/humidified circuits (16.8 2.6%, 16.5 4.3%, and 17 1.0%, respectively). In contrast, the jet nebulizer was most efficient in position 3 under both non-humidified (14.7 1.5%) and heated/humidified (6.0 0.1%) conditions. In positions 2 and 3, all devices delivered approximately 2-fold more drug under non-humidified than under heated/humidified conditions (P < .01). At position 1 only the pMDI delivered substantially more drug than with the non-humidified circuit. CONCLUSION: During mechanical ventilation the optimal drug delivery efficiency depends on the

Patricia Dailey - One of the best experts on this subject based on the ideXlab platform.

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Arzu Ari, Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O(2)) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (V(t)) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O(2) (100%) and heliox (80/20% mixture). A total of 12 runs, using O(2) and heliox were conducted at 3 and 6 L/min (n = 3). Drug was collected on an Absolute Filter, eluted and measured using spectrophotometry. The percent inhaled dose (mean ± SD) was similar with heliox and O(2) at 3 L/min (11.41 ± 1.54 and 10.65 ± 0.51, respectively; P = 0.465). However at 6 L/min drug deposition was ≥ 2-fold greater with heliox (5.42 ± 0.54) than O(2) (1.95 ± 0.50; P = 0.01). Using a pediatric model of HFNC, reducing delivered flow from 6 to 3 L/min increased inhaled albuterol delivery ≥ 2-fold but eliminated the increase in inhaled drug efficiency associated with heliox.

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Summary. Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O2) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (Vt) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O2 (100%) and heliox (80/20% mixture). A total of 12 runs, using O2 and heliox were conducted at 3 and 6 L/ min (n ¼ 3). Drug was collected on an Absolute Filter, eluted and measured using spectropho

Meryl M Sheard - One of the best experts on this subject based on the ideXlab platform.

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Arzu Ari, Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O(2)) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (V(t)) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O(2) (100%) and heliox (80/20% mixture). A total of 12 runs, using O(2) and heliox were conducted at 3 and 6 L/min (n = 3). Drug was collected on an Absolute Filter, eluted and measured using spectrophotometry. The percent inhaled dose (mean ± SD) was similar with heliox and O(2) at 3 L/min (11.41 ± 1.54 and 10.65 ± 0.51, respectively; P = 0.465). However at 6 L/min drug deposition was ≥ 2-fold greater with heliox (5.42 ± 0.54) than O(2) (1.95 ± 0.50; P = 0.01). Using a pediatric model of HFNC, reducing delivered flow from 6 to 3 L/min increased inhaled albuterol delivery ≥ 2-fold but eliminated the increase in inhaled drug efficiency associated with heliox.

  • in vitro comparison of heliox and oxygen in aerosol delivery using pediatric high flow nasal cannula
    Pediatric Pulmonology, 2011
    Co-Authors: Robert Harwood, Patricia Dailey, Meryl M Sheard, James B Fink
    Abstract:

    Summary. Drug administration via high flow nasal cannula (HFNC) has been described in pediatrics but the amount of albuterol delivery with an HFNC is not known. The purpose of this study is to quantify aerosol delivery with heliox and oxygen (O2) in a model of pediatric ventilation. A vibrating mesh nebulizer (Aeroneb Solo, Aerogen) was placed on the inspiratory inlet of a heated humidifier and heated wire circuit attached to a pediatric nasal cannula (Optiflow, Fisher & Paykel). Breathing parameters were tidal volume (Vt) 100 ml, respiratory rate (RR) 20/min, and I-time of 1 sec. Albuterol sulfate (2.5 mg/3 ml) was administered through a pediatric HFNC with O2 (100%) and heliox (80/20% mixture). A total of 12 runs, using O2 and heliox were conducted at 3 and 6 L/ min (n ¼ 3). Drug was collected on an Absolute Filter, eluted and measured using spectropho