INVENTION DISCLOSURE FORM Example-2 for WPI “Patent Disclosure 101” Seminar

Title of invention: Fluorescent Intensity and Lifetime Measurement of Platinum-Porphyrin Film for Determining the Sensitivity of Transcutaneous Oxygen Sensor

 

Department:                          Dean:                          Is this an IQP or MQP?  

  1. Big Picture: What is the ultimate “one sentence” possible product? What need does it address?  In this study, we conducted an experiment to analyze the performance of both the intensity and lifetime measurement techniques of a platinum-porphyrin fluorescent film, the sensing material, under different concentrations of oxygen. A prototype that deploys an analog front-end, a light-emitting diode driver with a power management block is implemented on a printed circuit board with commercial off-the-shelf components. The system resolves changes in oxygen pressure from 0.5 mmHg to 500 mmHg with a power consumption of 132 mW. This system could be potentially used to measure the concentration of oxygen diffused through the skin, also known as transcutaneous measurement of oxygen. These measurements are key to developing more sophisticated read-out circuits for reliable and sensitive medical purpose for transcutaneous oxygen sensing.
  1. Inventor(s) –Identify all individuals who have made significant intellectual contributions to this invention’s advance over prior technology, but do not include anyone merely because she/he has carried out some of the experimental work.

For Each inventor:

Given Name:

Family Name:

Faculty Title/Position:

If student: undergraduate/graduate, expected year of graduation

WPI email:                                         Non WPI Email:

 

 

  1. Specify any other inventor(s) who is/are an employee of an organization other than WPI and the institutional affiliation.

 

  1. Describe the “Important Customer Need or Needs” that you are addressing.  What is the specific market segment addressed and how big is it? Do you have a possible business model for your invention?

 Drugs, severe infection and trauma, and diseases such as chronic obstructive pulmonary disease (COPD) and bronchiolitis are some of the common causes of abnormal respiratory activity [1]. In a hospital setting, unless a patient is at risk, respiration parameters along with other vital signs are monitored every eight hours [2].

However, it takes a few minutes for respiratory disorders to become life-threatening [1]. Additionally, frequent alternations to respiration parameters reflect compromised neurological and cardiopulmonary functions [3].

Therefore, caregivers want to frequently and accurately measure the respiration parameters such as respiration rate, peripheral blood saturation, and partial pressure of CO2 and O2 in the blood [4]. 

While arterial blood gas (ABG) monitoring is the gold standard for blood gas analysis for measuring the partial pressure of oxygen (PaO2) in arterial blood, it is an invasive and painful process. Hence it is not applicable for continuous monitoring [5], [6]. Pulse oximetry, a surrogate measurement method of arterial oxygen saturation (SaO2) is a commonly used method to assess the blood oxygenation. In current practice, pulse oximetry is employed to measure the peripheral blood oxygen saturation (SpO2) to estimate SaO2. There is an accurate correlation only for high values of SpO2 and PaO2; however, there is inconsistency in measurement values between different patients as values fall off [7], [8]. 

Measuring the partial pressure of transcutaneous oxygen (PtcO2) is the partial pressure of oxygen (PaO2) in arterial blood[8], [9]. Traditionally, the partial pressure of transcutaneous oxygen (PtcO2) has been measured using Clark electrodes, which uses platinum electrodes, a heating element, and an oxygen-permeable membrane [10]. The insufficient sensitivity of this method makes heating to 42-45C necessary to increase the O2 concentration in the gas above the targeted skin area as it increases the diffusion of oxygen molecules from the blood capillaries to the skin. Even though the electrochemical method is a successful example of monitoring partial pressure of transcutaneous oxygen (PtcO2), the requirement of a heating element negatively affects the feasibility of a long term, continuous monitoring wearable device. An alternative approach is to use fluorescence methods for measuring the partial pressure of transcutaneous oxygen (PtcO2) [11], [12]. The availability and advancements in thin-film sensors, optoelectronics, and sensor materials enable sensitive and accurate O2 measurements.

 

In this paper, we have demonstrated a PtcO2 monitoring prototype that employs two different techniques for assessing the oxygen concentration value; an intensity (a.k.a amplitude) based and a lifetime (a.k.a decay) based measurements. We conducted an experiment to analyze the performance of both the intensity and lifetime measurement techniques of a platinum-porphyrin fluorescent film, the sensing material, under different concentrations of oxygen.

A prototype that deploys an analog front-end, a light-emitting diode driver with a power management block is implemented on a printed circuit board with commercial off-the-shelf components. The system resolves changes in oxygen pressure from 0.5 mmHg to 500 mmHg with a power consumption of 132 mW. This system could be potentially used to measure the concentration of oxygen diffused through the skin, also known as a transcutaneous measurement of oxygen. These measurements are key to developing more sophisticated read-out circuits for reliable and sensitive medical purpose for transcutaneous oxygen sensing.

 

  1. Describe your technical “Approach” for how you will address that need..   Include the functions and the invention fulfills and the “physical” solution to the design problem posed by functions Feel free to attach manuscripts, abstracts, drawings, or videos describing the technical aspects of the invention.

 The fluorescent-based method presented in uses a platinum porphyrin (Pt-porphyrin) fluorescent thin film. It consists of functional groups known as fluorophores die suspended polymer whose fluorescence is quenched or suppressed the presence O2  Pt-porphyrin based films have been used for oxygen sensing applications ranging from waste water management to partial pressure transcutaneous sensors  When a photon with certain energy (usually shorter wavelength) interacts material fluorophore excited its ground state. As molecule returns state longer wavelength and lower level emitted material. In molecular this process limited quenched by an interaction between and the fluorophore.

For example when film exposed blue light peak emission (l) 450 nm it re-emits red l 650 nm. intensity re-emitted inversely proportional concentration O2. mechanics can either be based on transfer electron depending  The kinematics quenching is described Stern-Volmer relationship.

The measured terms lifetime t Q (mol _m3) Kq rate coefficient fast reaction probability close unity coefficient approximated R gas T Kelvins h viscosity solution treated m3 _ mol1 s1.

The intrinsic property is immune to most external changes Different compounds different levels. Fluorescent range tens nanoseconds microseconds compound. For a Pt-porphyrin-based we expect similar order 20 – 60 ms.

In PtcO2 sensor has developed measure change However intensity-based approach vulnerable variations optical path degradation drift detector source. The (t) preferred way develop florescent independent these factors.

An indium gallium nitride (InGaN) emitting diode (LED) (D3) dominant 453 was excite [ Changes amount present environment surrounding N-channel MOSFET (M1) driver externally controlled driving voltage VDRIVE drive LED the current M1 on. R7 pulls cathode D3 up match anode ensuring off.

The analog front end (AFE) trans-impedance amplifier (TIA) (U1) configured gain 10 MW (R1)  deployed convert photocurrent D1 into measurable voltage and  pF capacitor (C1) included feedback network prevent peaking stabilize the.

TIA. bandwidth TIA 14 kHz. low-pass filter (R2 C2) provision out any high-frequency noise if needed a second (U2) provides low impedance guard ring around sensitive input well biasing D2 R4 R5 protective circuitry U2.

The powered 3 V lithium coin cell battery DC power supply two boost converters 3.3 5 circuit converters keep stable output.

The experiment setup shown 4 employed 46 mm inner diameter quartz tube cut 24 inches long rubber stoppers were set to control concentration. Four 18 AWG nickel wires pushed through one stopper provide airtight electrical interface inside-outside tube. To simplify testing oxygen determined steps are exciting driven arbitrarily chosen 100 Hz square wave 20% duty cycle. The procedure repeated three times to ensure reading gauge just oxygen. Test structure placed vessel (a) reflectance surface (paper) (b) (foil) 6. Transient response falls different oxygen levels a) b) higher (foil).  Variability of human skin conducted reflective backings for paper foil test.

This lifetime measurement technique has superior features such as little or no sensitivity to changes in the optical path, degradation of the film or photobleaching. In this study, we conducted an experiment to analyze the performance of both the intensity and lifetime measurement techniques of a platinum-porphyrin fluorescent film, the sensing material, under different concentrations of oxygen. A prototype that deploys an analog front-end, a light-emitting diode driver and a power management block is implemented on a printed circuit board with commercial off-the-shelf components. The system resolves changes in oxygen pressure from 0.5 mmHg to 500 mmHg with a power consumption of 132 mW. This system could be potentially used to measure the concentration of oxygen diffused through the skin, also known as transcutaneous measurement of oxygen. These measurements are key to developing more sophisticated read-out circuits for reliable and sensitive medical purpose transcutaneous oxygen sensing.

In this study, we conducted an experiment to analyze the performance of both the intensity and lifetime measurement techniques of a platinum-porphyrin fluorescent film, the sensing material, under different concentrations of oxygen. A prototype that deploys an analog front-end, a light-emitting diode driver with a power management block is implemented on a printed circuit board with commercial off-the-shelf components. The system resolves changes in oxygen pressure from 0.5 mmHg to 500 mmHg with a power consumption of 132 mW. This system could be potentially used to measure the concentration of oxygen diffused through the skin, also known as transcutaneous measurement of oxygen. These measurements are key to developing more sophisticated read-out circuits for reliable and sensitive medical purpose for transcutaneous oxygen sensing.

 

**REVISED DESCRIPTION TEXT REPLACING ACRONYMS with THEIR ENGLISH WORDS in Items 4. and 5.:

4. Drugs, severe infection and trauma, and diseases such as chronic obstructive pulmonary disease (COPD) and bronchiolitis are some of the common causes of abnormal respiratory activity [1]. In a hospital setting, unless a patient is at

risk, respiration parameters along with other vital signs are monitored every eight hours [2]. However, it takes a few minutes for respiratory disorders to become life-threatening [1]. Additionally, frequent alternations to respiration parameters

reflect compromised neurological and cardiopulmonary functions [3]. Therefore, caregivers want to frequently and accurately measure the respiration parameters such as respiration rate, peripheral blood saturation, and partial pressure of carbon dioxide – and oxygen in the blood [4]. 

While arterial blood gas monitoring is the gold standard for blood gas analysis for measuring the partial pressure of oxygen in arterial blood, it is an invasive and painful process. Hence it is not applicable for continuous monitoring [5], [6]. Pulse oximetry, a surrogate measurement method of arterial oxygen saturation  is a commonly used method to assess the blood oxygenation. In current practice, pulse oximetry is employed to measure the peripheral blood oxygen saturation  to estimate partial pressure of oxygen; however, there is inconsistency in measurement values between different patients as values fall off [7], [8]. 

Measuring the partial pressure of transcutaneous oxygen is a partial pressure of oxygen. [8], [9]. Traditionally, the partial pressure of transcutaneous oxygen has been measured using Clark electrodes, which uses platinum electrodes, a heating element, and an oxygen-permeable membrane [10]. The insufficient sensitivity of this method makes heating to 42-45 C necessary to increase the O2 concentration in the gas above the targeted skin area as it increases the diffusion of oxygen molecules from the blood capillaries to the skin. Even though the electrochemical method is a successful example of monitoring the partial pressure of transcutaneous oxygen, the requirement of a heating element negatively affects the feasibility of a long term, continuous monitoring wearable device. An alternative approach is to use fluorescence methods for measuring the partial pressure of transcutaneous oxygen [11], [12]. The availability and advancements in thin-film sensors, optoelectronics, and sensor materials enables sensitive and accurate O2 measurements. 

In this paper, we have demonstrated a partial pressure of transcutaneous oxygen monitoring prototype that employs two different techniques for assessing the oxygen concentration value; an intensity or amplitude based and a lifetime or decay based measurements. 

 **End of revised Item 4. text.

** REVISED  ITEM 5 TEXT with ACRONYMS REPLACED WITH FULL-TEXT TERMS:

Item 5: Describe your technical “Approach” for how you will address that need.  Include the functions and the invention fulfills and the “physical” solution to the design problem posed by functions Feel free to attach manuscripts, abstracts, drawings, or videos describing the technical aspects of the invention

The fluorescent-based method presented in uses a platinum porphyrin (Pt-porphyrin) fluorescent thin film. It consists of functional groups known as fluorophores die suspended polymer whose fluorescence is quenched or suppressed the presence O2  platinum porphyrin based films have been used for oxygen sensing applications ranging from wastewater management to partial pressure transcutaneous sensors  When a photon with certain energy (usually shorter wavelength) interacts material fluorophore excited its ground state. As molecule returns state longer wavelength and lower level emitted material. In molecular this process limited quenched by an interaction between and the fluorophore.

For example, when film exposed blue light peak emission at 450 nm it re-emits red at 650 nm. intensity re-emitted inversely proportional concentration O2. mechanics can either be based on transfer electron depending  The kinematics quenching is described Stern-Volmer relationship.

The measured terms lifetime rate coefficient fast reaction probability close unity coefficient approximated R-gas T-Kelvins viscosity solution treated film.

The intrinsic property is immune to most external changes for Different compounds at different levels. Fluorescent range tens nanoseconds to microseconds compound. For a platinum porphyrin-based film,  we expect a similar order of 20 – 60ms.

In this report, the partial pressure of transcutaneous oxygen sensor was developed to measure change.  However, an intensity-based approach is vulnerable to variations optical path degradation drift detector source. The preferred way is to develop florescent independent of these factors.

An indium gallium nitride light-emitting diode  (D3) dominant 453 excited – Changes amount present environment surrounding N-channel MOSFET  driver externally controlled driving voltage drive light-emitting diode the current M1 on resistor R7 pulls cathode D3 up match anode ensuring off.

The analog front end trans-impedance amplifier (U1) configured gain 10 MW (R1)  deployed convert photocurrent D1 into measurable voltage and pico-Farad capacitor (C1) included feedback network prevent peaking stabilize.

TIA bandwidth 14 kHz low-pass filter (R2-C2) provision out any high-frequency noise if needed a second trans-impedance amplifier (U2) provides low impedance guard ring around sensitive input well biasing the D2 resistors R4-R5 protective circuitry for the trans-impedance amplifier U2.

The powered 3-Volt lithium coin cell battery gives DC power supply two boost converters 3.3.5 circuit converters keep stable output.

The experiment setup shown in 4 employed a 46 mm inner diameter quartz tube cut 24 inches with long rubber stoppers were set to control concentration. Four 18 Gauge nickel wires pushed through one stopper provide airtight electrical interface inside-outside tube. To simplify testing oxygen determined steps are exciting driven arbitrarily chosen 100 Hz square wave 20% duty cycle. The procedure repeated three times to ensure the reading gauge is just oxygen. Test structure placed vessel (a) reflectance surface (paper) (b) (foil) 6. Transient response falls in different oxygen levels higher (foil). Variability of human skin conducted reflective backings for paper foil test.

The lifetime measurement technique has superior features such as little or no sensitivity to changes in the optical path, degradation of the film or photobleaching. In this study, we conducted an experiment to analyze the performance of both the intensity and lifetime measurement techniques of a platinum-porphyrin fluorescent film, the sensing material, under different concentrations of oxygen. A prototype that deploys an analog front-end, a light-emitting diode driver with a power management block is implemented on a printed circuit board with commercial off-the-shelf components. The system resolves changes in oxygen pressure from 0.5 mmHg to 500 mmHg with a power consumption of 132mW. This system could be potentially used to measure the concentration of oxygen diffused through the skin, also known as a transcutaneous measurement of oxygen. These measurements are key to developing more sophisticated read-out circuits for reliable and sensitive medical purpose transcutaneous oxygen sensing.

** End of revised Item 5.

  1. Describe the quantitative “Benefits/costs” of your approach. Why is your idea of significant worth to somebody?

 

  1. Who is the “Competition” and why are the benefits/costs of your approach significantly better? Quantify: is it 2-10 times better? 

            [Seminar Project Group should determine these.] 

 

  1. Please provide key words that best identify with your idea:

             [Seminar Project Group should determine these.]

 

  1. Prior Art (Relevant recent “background” o successfully determine the patentability of this invention, it will be necessary to compare it to any existing technology, i.e., “prior art.” Provide any references to assist in this evaluation.) You should go to https://www.searchrealfast.com/wpi/otc-v2  and register with your WPI email for a quick and efficient way to search for prior art.  Use your key words to assist in the search.  A quick tutorial can be found at: https://www.searchrealfast.com/faculty

 

  1. What level of proof or evidence of viability do you have for the invention? Working prototype, proof of concept experiments, etc.?

 

  1. Has this invention been disclosed to others, either verbally or in written form (date, place, to whom, method of disclosure)?

 

  1. Indicate any pending disclosures (date, place, to whom, method of disclosure).

 

  1. Indicate any potential commercial licensees that you think may be interested in this invention.

 

  1. Identify any grants, sponsors or projects (provide grant/contract number) under which either conception or first reduction to practice occurred, including partial funding and Federal “formula” funding. Also list any related projects and/or inventions and any other potential claimants to rights in this invention.

 

Inventor Signature (1): _______________________________________    ___________              ____________

 

Print name: _____________________________

 

Home Address, Including City, State and Zip

 

Inventor’s Signature (2)                                           Date                            Citizenship

 

________________________________________    ___________              ____________

 

Print name:______________________________

 

Home Address, Including City, State and Zip

 

 

 

Inventor’s Signature (3)                                           Date                            Citizenship

 

________________________________________    ___________              ____________

 

Print name: _____________________________

 

Home Address, Including City, State and Zip 

NOTE:  WPI will assume that any eventual revenue from this invention will be split equally, unless there is a different split as acknowledged below: